JPH06247571A - Image forming device - Google Patents

Abstract

(57) [Summary] [Object] To provide an image forming apparatus having high productivity of image formation. [Configuration] When a predetermined copy operation is completed (S (3
9) 1 step), the current position of the sheet feeding unit is detected (S (39) 2 step), and the sheet storage unit that stores the most frequently used sheet size sheet is detected (S).
(39) Step 3), the paper feed unit is moved to a paper feedable position corresponding to the sheet storage unit that stores the most frequently used sheet size sheet, and the paper feed unit is made to wait at that position (S ( 39) 4 steps). If the sheet storage tray that has been fed when the copy operation is completed is the most frequently used sheet storage unit, it does not move and stands by at the same sheet feeding position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus provided with a sheet feeding device accommodating a plurality of types of recording sheets,
More specifically, the image forming apparatus is equipped with a sheet feeding device that replenishes a recording sheet in one recording sheet accommodation stage and moves the recording sheet from the recording sheet accommodation stage to another recording sheet accommodation stage to replenish the sheet. Regarding

[0002]

2. Description of the Related Art Conventionally, a so-called front loading type copying machine has been proposed in which paper can be supplied from the front of an operator in order to save space in an office. This type of copier has multiple paper feed stages, so if you need to replenish the lowermost sheet, you must bend the lower leg significantly to improve operability. There is room for In addition, the number of Westerners working in Japan is increasing due to the internationalization of work in recent years, but in general, Westerners do not have a habit of sitting on tatami mats, and it is difficult to bend their knees significantly when replenishing paper. Therefore, it tends to be very disliked. This is of course true when used in Western countries.

That is, various types of sheet feeding devices have been proposed and used in the past. Particularly, regarding the replenishment of recording sheets, it is widely used in image forming apparatuses such as copying machines, facsimiles, printers, and printing apparatuses. There is a problem in operability regarding the position of replenishing the recording sheet with respect to the sheet feeding means. That is, in general, the conventional paper feeding means, in other words, the paper feeding device, is often provided in the lower part of the image forming apparatus main body in the system, and the sheet storage in which the recording sheets of different sizes are provided in multiple stages When the recording sheets are replenished, they have to bend down as described above when replenishing the recording sheets, and the lower the sheet accommodating stage, the more difficult the posture is to be constrained. . As a technique for avoiding this, for example, a technique disclosed in Japanese Patent Laid-Open No. 64-29873 is known.

This prior art relates to a large-capacity sheet feeding device that stores a large number of single-sized recording sheets and supplies them to the image forming apparatus main body, and a plurality of storage chambers for storing the recording sheets are provided. Therefore, the operator can replenish the recording sheets to the uppermost storage chamber. In this structure, the recording sheets are placed between the recording sheet storage chambers,
Two movable guides that can be swung in the left-right direction are provided, and the movable guides are appropriately swung according to the remaining amount of recording sheets in the lowermost storage chamber in which the paper feed unit is provided and other storage chambers. The recording sheets are sequentially dropped from the upper storage chamber to the lower storage chamber by their own weight, and the recording sheets are fed from the lowermost storage chamber to an image forming apparatus, in this case, a facsimile.

[0005]

By the way, in the above apparatus, the recording sheet is dropped by its own weight between the sheet accommodating sections partitioned for sheet replenishment, and the sheet at the bottom is provided only with the sheet feeding section. Since the recording sheet replenishment position can be set to a relatively high position by sequentially moving the recording sheets to the storage portion, the operability associated with the sheet replenishment is improved. However, in this method, the impact force generated by the collision of the recording sheet onto the lower sheet storage portion when it falls by its own weight, the wind pressure on the recording sheet at the time of its own weight drop, and the shaking of the movable guide on which the recording sheet is placed. An external force such as a frictional force between the recording sheet and the movable guide during the movement causes the recording sheet to fall into a non-uniform state after being dropped. Therefore, due to the non-uniform state, there are cases where a self-weight drop failure in the next-stage sheet storage section and a sheet feeding failure such as a jam or a skew during the sheet feeding operation occur.

The above-mentioned prior art is intended for a large-capacity sheet feeding device that stores a large number of single-size recording sheets and supplies them to the image forming apparatus main body. I couldn't adapt.

Therefore, there is provided a means for moving a specific sheet, for example, the uppermost sheet storage portion to a replenishment stage, replenishing the replenishment stage with a sheet, and moving the sheet from the replenishment stage to another sheet storage portion. The applicant has already proposed an apparatus capable of replenishing sheets and feeding and conveying the sheets to the image forming means side.

In the previously proposed apparatus, the mechanism for replenishing and the mechanism for feeding are the same mechanism (one sheet feeding unit).
Therefore, it is necessary to move the sheet feeding unit to the sheet storage stage for feeding the sheet to feed the sheet.
However, since sheets of a plurality of sheet sizes are randomly stored in each tier, there is a tendency that the total time required for image formation increases with the movement of the means, which is unavoidable. The productivity of image formation may be reduced.

The present invention has been made in view of the actual situation of the prior art as described above, and an object thereof is to provide an image forming apparatus in which a plurality of recording sheet storage portions for storing recording sheets of different sizes are installed. An object of the present invention is to provide an image forming apparatus capable of improving the productivity of formation.

[0010]

In order to achieve the above object, a first means is that a plurality of recording sheet storage stages are provided in the vertical direction, and the recording sheet is stored in only one preset recording sheet storage stage. In an image forming apparatus equipped with a sheet feeding device for replenishing paper, a recording sheet is moved to one of the recording sheet storage stages other than the preset one recording sheet storage stage, and another recording sheet storage stage is stored. A sheet feeding unit that picks up a recording sheet from the stack and conveys it to the image forming unit side of the image forming apparatus; and a first sheet size detecting unit that detects the size of the recording sheet stored in the other recording sheet storage stage. A first storage unit that stores the size of the recording sheet detected by the first sheet size detection unit; Second sheet size detection means for detecting the size of the recording sheet, second storage means for storing the size of the recording sheet detected by the second sheet size detection means, and storage of the second storage means Based on the information, the most frequent recording sheet storage stage detecting means for detecting the most frequent recording sheet storage stage in which the recording sheet of the sheet size having the highest image formation frequency is stored, and the sheet feeding after the completion of a series of image forming operations. The drive control means for moving the unit to the sheet feeding position corresponding to the most frequent recording sheet storage stage is provided.

In the second means, a plurality of recording sheet storage stages are provided in the vertical direction, and the number of recording sheet storage stages is set in advance.
In an image forming apparatus provided with a paper feeding device for supplying recording sheets only to one recording sheet storage stage, the recording sheet is stored in one of the recording sheet storage stages other than the preset one recording sheet storage stage. A sheet feeding unit that moves and picks up a recording sheet from another recording sheet storage stage and conveys it to the image forming unit side of the image forming apparatus, and detects the size of the recording sheet stored in the other recording sheet storage stage. First sheet size detection means, first storage means for storing the size of the recording sheet detected by the first sheet size detection means, and image formation start detection for detecting image formation start by the image forming means. Means, position detecting means for detecting the position of the paper feeding unit, and the size of the recording sheet for which image formation has been completed by the image forming means. Based on the storage information of the second sheet size detection means for detecting the recording sheet size, the second storage means for storing the size of the recording sheet detected by the second sheet size detection means, and the storage information of the second storage means. The most frequent recording sheet storage stage detecting means for detecting the most frequent recording sheet storage stage in which the recording sheet of the sheet size with the highest image forming frequency is stored, and when the image formation start is detected,
Drive control means for moving the paper feed unit from the paper feed position detected by the position detection means to the paper feed position corresponding to the most frequent recording sheet storage stage is provided.

[0012]

According to the above-mentioned first means, the recording sheets are supplied to the preset recording sheet accommodating stage and moved to the recording sheet accommodating stage which is, for example, the paper end by the paper feeding unit, and the empty recording sheet accommodating stage is accommodated. A predetermined supply is performed on the stage. Then, the recording sheet is picked up from the recording sheet storage stage other than the replenishment stage by the same sheet feeding unit and is conveyed to the image forming means side to form an image.

The second sheet size detecting means detects the size of the recording sheet on which image formation has been completed, and this size is stored in the second storage means. The most frequently recorded recording sheet accommodation stage detecting means stores the information stored in the second storage means and the information stored in the first storage means that stores the size of the recording sheet accommodated in the recording sheet storage stage. Detects the most frequently used recording sheet storage stage, and in response to this detection result, the drive control unit responds to the most frequently used recording sheet storage stage when the current series of image forming operations is completed. The sheet feeding unit is moved to the sheet feeding position to be prepared for the next image forming operation. As a result, when the next image formation is input, the probability that the paper feeding unit can immediately pick up the recording sheet from the recording sheet storage stage having the highest frequency of use and convey the recording sheet to the image forming unit side increases. The average time to supply the recording sheet to the printer will be the shortest and the productivity will be improved.

According to the second means, as in the first means, the sheet feeding unit is moved to the sheet feeding position corresponding to the recording sheet storage stage which is most frequently used, and the loss time for feeding sheets is minimized. However, if there is an input to start image formation at that time, the paper feed corresponding to the recording sheet storage tray that is most frequently used from the paper feed position that was located when the input was made. It is set to move to a position.
Of course, it does not move when it is located at the position corresponding to the most frequent recording sheet storage stage before the start of image formation.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an internal block diagram showing the entire image forming apparatus according to an embodiment of the present invention. First, the overall system of the image forming apparatus according to the embodiment will be described with reference to FIG.

In FIG. 1, this system comprises a sheet feeding device 1 and an image forming device 2. The sheet feeding device 1 is arranged in the lower half of the entire apparatus, and the image forming device 2 is arranged in the upper part thereof. There is. An automatic document feeder 3 is provided above the image forming apparatus 2. A contact glass 4 is installed at the upper end of the image forming apparatus, which is the lower surface of the automatic document feeder 3, and the original set on the automatic document feeder 3 is automatically placed on the contact glass 4 when a copy signal is input. Be delivered.

The document fed on the contact glass 4 is read by the image reading section 5 provided in the image forming apparatus 2 and converted into a digital signal. The image writing unit 6 irradiates the photoconductor 7 with laser light based on the digital signal. The photoconductor 7 rotates clockwise when a copy signal is input, and is charged to a uniform potential by the charging charger 8. Image information is converted into a latent image by the irradiation of the laser light in the image writing unit 6, and the developing device is developed. It is visualized by 9. Then, the image visualized by the toner is transferred to the transfer charge 10
Is transferred onto the sheet by. On the other hand, the toner remaining on the photoconductor 7 is cleaned by the cleaning device 11, and the surface of the photoconductor 7 and the static elimination lamp 12 are uniformly discharged. Each of these steps forms one cycle of image formation.

The sheet is fed from the sheet feeding device 1 to the registration roller 20 section and is fed to the transfer section at a predetermined timing. Alternatively, the sheets may be fed from the so-called manual feed tray 19. After the transfer, the sheet passes through the transport device 13, is fixed by the fixing device 14, and is discharged to the paper discharge unit 15. Note that these image forming steps are known electrophotographic processes.

Inside the sheet feeding device 1, a sheet storage portion 270 including nine storage stages is arranged, and only the uppermost stage thereof can be pulled out toward the front side of the device. 2 to
The sheet accommodating units 270b to 270 of the ninth stage have exactly the same configuration, and fulfill the function of a normally used sheet feeding cassette. In addition, hereinafter, the subscript a is attached to the one corresponding to the top row.
A concrete number of stages is clearly shown by adding an alphabet such as a subscript b to those corresponding to the second stage, and a subscript i to those corresponding to the ninth stage. Also, the sheet storage unit 2
The front cover 70 is integrally covered with the front cover, and is not structured to be detached from the paper feeding device 1. The sheet storage units 270a to 270 of the respective stages include a sheet stack tray 246 and an end fence 350, respectively.

As described above, since the paper feeding cassette is not used and it is not necessary to attach and detach the cassette naturally, the number of paper feeding stages more than double that of the paper feeding cassette type can be set in the space of a normal paper feeding device. Can be secured. In the embodiment, about 250 sheets are assumed for each stage,
It is not particularly limited. In addition, since a maximum of eight types of sheet sizes can be supported, the user hardly feels the hassle of not having a desired size. However, in most cases, the normally used size is limited, and it is also possible to set a plurality of frequently used sizes in a plurality of stages.

The first-stage sheet stack tray 246 is a sheet replenishing tray when a sheet end occurs in the sheet storage section 270, and usually no sheets are set. The sheet replenishment tray 246 is located at an intermediate height of the entire machine, and all the sheet replenishment is set here, so that the user can work without bending over.

On the right side of the sheet storage unit 270, only one sheet feeding unit 406 is provided, and the sheet is fed from each tray by moving up and down from the 1st to 9th stages. Usually, since each tray has a paper feed mechanism, there is a problem that the larger the number of trays, the more cost and space are required, which is greatly improved. On the right side of the sheet feeding unit 406, a conveyor belt 419 is stretched over the entire length in the vertical direction from the bottom to the top of the feeding device 1 so as to correspond to the sheets fed from the first to ninth trays. The conveyor belt 419 is charged by the charging charger 420 inside the conveyor belt 419, electrostatically adsorbs the sheet fed by the sheet feeding unit 406, and conveys the sheet upward by its own rotation.
And the conveyance guide plate 55 provided in the middle of the sheet feeding device 1,
Separate the sheets. The separated sheets are guided by the pair of transport guide plates 55, and by the pair of transport rollers 56.
It is fed to 20 parts of the registration rollers.

Below the conveyor belt 419 is a drive roller 41.
7, and the upper part thereof is supported by the discharging roller 418. Since the sheet is electrostatically adsorbed by the conveyor belt 419, the charge is grounded by the charge eliminating roller 418 to facilitate separation. In addition, the static elimination roller 418
Instead of this, a static eliminator charger may be separately provided.

In order to deal with sheet jams and maintenance, the paper feeding unit 406 and the conveyor belt 419 are integrated and can be opened and closed to the right from the paper feeding device 1 with the back side as a fulcrum. When the sheet feeding unit opening / closing unit 17 is open to the right, the sheet storage unit 270 is pushed from the right side to the sheet feeding unit 4
Since 06 is in an open state from the left side, it is possible to take in and out of the hand, and jam processing and the like can be performed.

When the sheet end occurs, the sheet is held by the sheet feeding unit 406 to move between the trays (described later), but at that time, the sheet stacking tray 246 does not hinder the movement of the sheet. A mechanism for retracting to the left is provided. The sheet stacking tray 246 is bendable in the sheet feeding direction, and when the sheet stacking tray 246 retracts, the sheet stacking tray 246 is gradually folded and stored in the tray storage section 60 from the left end.

The tray accommodating portion 60 is provided at the left end of the sheet feeding device 1 and has a vertically long space capable of accommodating one sheet stacking tray 246. That is, the plurality of sheet stacking trays 246 are not accommodated in the tray accommodating section 60 at the same time. As described above, the sheet stacking tray 246 can be opened / closed in a space-saving manner, which contributes to downsizing of the apparatus and multi-tiering of the trays.

Here, the outline of the structure for moving the sheet between the trays will be described.

The sheet moving means for moving the sheet bundle placed on one tray to another tray is composed of a sheet feeding means, that is, a paper feeding unit 406. The sheet feeding unit 406 is provided with a pressure holding plate 468 and a calling roller 436, and the sheet storage unit 27 to be moved is moved.
0 (any one of a to i) is made to face the pressure holding plate 468 in a lowered state, and the end fence 350 pushes out the sheet bundle until the tip hits the pressure holding plate 468,
Next, when the pressure holding plate 468 is raised, the pressure holding plate 468 can be held with the calling roller 436 at a predetermined pressure. In this state, the sheet stack tray 246 of the sheet storage section 270 (a to i) is retracted to the tray storage section 60 side, and the sheet feeding unit 406 is lowered to a position facing the storage stage immediately below. The sheet stacking tray 246 of the storage stage is advanced to the sheet feeding unit 406 side, the sheet bundle is placed on the sheet stacking tray 246, and the clamping force between the pressure holding plate 468 and the calling roller 436 is released. Then, the sheet stack tray 246 is retracted to the sheet feeding position. By repeating this, even when the lowermost sheet storage portion 270i becomes empty, the empty sheet storage portion 270 (any one of a to i) can be simply provided by supplying the sheet to the uppermost sheet storage portion 270a. The seat will be replenished.

Further, with the above configuration, the device is devised so as to minimize the installation space. That is, on the left side of the apparatus, the paper discharge unit 15 is almost invisible from the image forming apparatus 2, and the paper feeding apparatus 1 also has the left cover 21.
It is completely covered with and has very little space on the left side. Further, on the right side of the device, it is sufficient to have a space for opening and closing a little during jam processing. The user can perform all operations including the seat setting on the front side of the device,
There is also an advantage that the installation location is not so restricted. Also,
Since the image forming apparatus 2 is assumed to have an optical system as a digital system, the transfer sheet can be set in a horizontal direction, for example, by providing a function such as vertical / horizontal conversion of an image.
In the present embodiment, the sheet size is B4 or more in the vertical feed and A4 or less in the horizontal feed so that the number of types of the sheet size set in the tray does not increase too much, but the present invention is not limited to this.

First, the setting of recording sheets in the sheet feeding device 1 will be described.

The sheet feeding device 1 provided below the image forming apparatus 2 is a multi-stage sheet feeding system of mixed sizes having a plurality of trays (sheet accommodating section 270) for placing sheets. When the sheet bundle 99 is set from a predetermined sheet replenishing port of the sheet feeding device 1, the sheet bundle 99 set directly on the first-stage sheet stacking tray 246a movable in the sheet conveying direction in the sheet feeding device 1 is conveyed. The sheet feeding unit 406 that moves to the upstream side in the direction and is movable up and down performs sheet feeding or the operation of moving the sheet bundle 99 to another sheet storage unit 270.

A plurality of sheet storage units 270 in the sheet feeding device 1
Among these, only the sheet stacking tray 246a of the uppermost first sheet storage portion 270a has an integrated structure with the drawer tray 100 that can be pulled out toward the front side, and the sheet supply port is provided only at this one location, and the other sheet storage portions are provided. Is a system in which the sheet bundle 99 is sequentially moved from the first sheet storage portion 270a, so that it is possible to feed paper at a high position (about 600 to 800 mm from the floor surface) as shown in FIG.
There is no need to bend and replenish the sheet bundle 99 when feeding to the lower pull-out type paper feed cassette 101 like the conventional multi-stage paper feed system in which each stage is a cassette as shown in FIG. The seat can be replenished in a very comfortable posture for the operator.

Further, since only the first sheet storage section 270a is used as the sheet feed port, the plural sheet storage sections 270 all have a common sheet replenishing port, and the conventional multi-stage sheet feeding as shown in FIG. It is not necessary to use a plurality of drawer-type cassettes having a complicated structure as compared with the apparatus.

In the embodiment shown in FIG. 2, when replenishing the sheets, first, the drawer tray 100 is pulled out to the front side, and the sheet bundle 99 is directly placed on the placing surface of the sheet stacking tray 246 for placing sheets. set. At that time, the movable sheet stacking tray 246 is located at the home position 252 which is a reference when the sheet stacking tray 246 shown in FIG. 4 is moved, and is stopped at another position, or is moving. In this case, the condition corresponds to the lock condition of the drawer tray 100, and the drawer tray 100 cannot be pulled out. When the drawer tray 100 is pulled out and the sheet setting is completed,
After the sheet is closed again, the sheet stacking tray 246 on which the sheet bundle 99 is placed advances in the direction of the sheet feeding unit 406 for sheet feeding or sheet movement.

The sheet stack 99 is directly fed to the sheet stacking tray 24.
6 is set so that the side of the sheet bundle 99 is abutted against the sheet side end reference wall inside the front side support member of the structure of the drawer tray 100, and the back side is a manually movable side. After moving the fence to a position where it comes into contact with the other end surface of the sheet bundle 99 and setting it, the drawer tray 100 is moved to the sheet feeding device 1 side,
The paper is stored in the paper feeding device 1.

In the above embodiment, the case where the drawer tray 100 for replenishing the sheet is manually pulled out has been described, but the present invention can also be realized as an automatic loading type in which the drawer tray is opened and closed with one touch. FIG. 5 shows an embodiment of the sheet feeding device 1 in the case of the auto loading system in which the drawer tray 100a is automatically opened and closed. The drawer tray 100a has a structure as shown in FIG.

That is, the drawer tray 100a is integrally molded by the pipe-shaped structure 110, and the side plates 111 and 11 are provided on the front side and the rear side in the drawing direction, respectively.
Two are provided. A guide member for the sheet stacking tray 246, which is movable in a direction parallel to the sheet conveying direction, is provided inside each of them, and the drawer tray 100a can be pulled out integrally with the tray 246 for mounting sheets.

A member parallel to the sheet width of the pipe-shaped structure 110 extends from the depth direction of the drawer tray 100a and is fitted with the guide members 113 and 114 of the drawer tray 100a provided on the main body side. is doing. As shown in the perspective view of FIG. 7, a rack 115 is provided on a member in the depth direction on the downstream side of the structure 110 in the sheet conveying direction, and the pinion 116 is meshed with the rack 115.
Is provided. The pinion 116 is driven by a drive source 117 provided inside the main body,
Moves the structure 110 by being guided by the guide members 113 and 114.

The operation of the automatic loading type drawer tray 100a is performed by the operator.
Operate the tray front cover 111, which is the front side plate of 0a, or the autoload key installed in the operation unit,
Alternatively, the drawer tray 100a is set to be opened with one touch by lightly pressing the front cover 11. The opening operation is not always performed, but lock conditions and unlock conditions of the drawer tray 100a described later are set in the main body side control unit, and the opening operation is performed according to the conditions.

When the auto load key is operated, the lock state of the lock member 118 of the drawer tray 100a is released, and then the drive source 117 in the main body is moved to the pinion 116.
The drive transmission is started, and the opening operation of the drawer tray 100a is started. In this embodiment, a DC motor is used as the drive source 117.

Next, a mechanism relating to sheet feeding and its control will be described.

As can be seen from FIG. 1, the sheet feeding unit 406 is arranged movably in the vertical direction of the sheet feeding apparatus 1 installed below the image forming apparatus 2, and has the number of sheet stacking trays 246. Regardless of the number, one sheet can supply all sheets and move sheets.

The paper feeding unit 406 includes a calling roller portion 435 and a pair of separation roller portions 4 as shown in the front view of FIG.
50, the pressure lever portion 453, and the pair of conveyance guide portions 4
86, the sheet leading edge aligning section 472, each sheet detecting section, and a driving section 484 that drives each roller (FIG. 20).
It is basically composed of and.

As shown in FIGS. 9 and 10, the calling roller portion 435 comprises a calling roller 436, a bracket 437 for holding the roller 436, and an auxiliary bracket 439 for supporting the bracket 437.
Reference numeral 7 is swingably supported about a rotation center 497. The roller 436 is pressed against the uppermost sheet 98 on the sheet stacking tray 246 at a predetermined pressure by their own weight and the elastic force of a tension spring (not shown) (see FIG. 10).
(C)) Then, the uppermost sheet 98 on the sheet stacking tray 246 and the sheets in the vicinity of the uppermost sheet 98 are the drive sources as shown in FIG. The rotation from the drive motor 407 is transmitted to the drive unit 484 in the paper feed unit 406 via the drive belt 409, and the call roller 436 is rotated and conveyed via the paper feed clutch. After that, the sheet feeding solenoid (not shown) retracts the calling roller portion 435 to the upper side 445 through the lever and separates the sheet from the sheet (FIG. 10D). Also,
The rotation of the drive motor 407 is transmitted to the drive roller 417 via the drive gear 496 and the idler 495. In addition,
In FIG. 9, reference numeral 446 is a fixed solenoid, reference numeral 44.
Reference numeral 7 is an arm, and reference numeral 448 is a lever.

The pair of separating roller units 450 are the uppermost sheet 98 of the sheets sent by the calling roller 436.
Only the sheet is separated from the other sheets on the lower side, and the driving force input from the driving unit 484 via the sheet feeding clutch is transmitted to convey the sheet to the next conveying unit and thereafter. Then, after that, in order to stop the sheet before the pair of separation roller units 450, as shown in FIG. 22, a sheet feeding feed roller 451 is provided on the upper side and a sheet separation roller is provided on the lower side. 452 are arranged and driven.

As shown in FIG. 10, the pressure lever portion 453 includes two types of levers 457 and 461 which are separately held at two fulcrums 458 and 462, respectively, and two types of levers 45.
7, 461 includes a pressure holding plate 468 that holds the fulcrums 459 and 463, respectively, and a dedicated drive motor 470 (FIG. 13) that drives them, and the sheet feeding unit 406 displays images on the sheets on the sheet stacking tray 246. When the sheet stack tray 246 is supplied to the forming apparatus 2, the sheet stack tray 246 is supported from below (FIG. 10C). Also, separately from this, the operation is performed when the sheet bundle 99 on the sheet stacking tray 246 is moved to the sheet stacking tray 246 of the subsequent sheet storage unit 270.

The sheet leading edge aligning portion 472 rotates about the fulcrum center as shown in FIGS.
Arms 473 for aligning 9a, a solenoid 476 for operating the arms 473, and a joint 4 for connecting them.
74 and a tension spring 475 for constantly retracting the arm to a position where it does not hinder the sheet conveyance. As a result, the feeding roller unit 435 and the pair of separation roller units 450 complete the supply of the sheets to the image forming apparatus 2, and the solenoid 476 is operated before the sheet stacking tray 246 is returned from the sheet feeding position (not shown) to the standby position. By the operation, the arm 473 is rotated about the fulcrum through the joint 474 from the retracted position 477 to the same surface as the sheet leading end reference wall or to the protruding position 478 slightly protruding to the sheet storage portion 270 side, and the arm is moved from the stacking position to the pair. The sheet protruding to the front of the separation roller unit 450 is returned to the original stacking position, and the leading ends of the sheets are aligned. In FIG. 14, reference numeral 487 is an upper guide plate and reference numeral 488 is a lower guide plate.

Each sheet-related detecting section detects the sheet height 92 on the sheet stacking tray 246 together with the call roller section 430 and a sheet upper limit detecting sensor 480 (FIG. 10).
A sheet end detection sensor 481 (FIG. 19) that detects the presence or absence of sheets on the sheet stacking tray 246, and a sheet remaining amount detection that detects the remaining amount of the sheet bundle 99 on the sheet stacking tray 246 together with the pressure lever portion 453. Sensor 482
(FIG. 13), a sheet for detecting whether the sheet has been conveyed within a predetermined time when the sheet is conveyed from the sheet stack tray 246 toward the image forming apparatus 2 by the calling roller section 435 and the pair of separation roller sections 450. It is composed of a tip detection sensor 483 (FIG. 36). The sheet end detection sensor 481 detects the sheet end by detecting the position of the other end of the actuator 498 (FIG. 19), which has one end contacting the sheet bundle 99 and rotates.

The paper feeding unit 406 moves as follows.

That is, as shown in FIGS. 16 and 17, the sheet feeding unit 406 has pulleys 411 and 414 with cables 415 connecting the moving motor 410 and the sheet feeding unit 406 in the front and rear at the stage where the sheet is to be fed. The sheet stacking tray 246 at that stage is moved from the standby position to the sheet feeding position by being driven by a moving motor via the feeding roller 436 in the sheet feeding unit 406.
Is set to the lower limit position 444 by the weight of the calling roller 436, the bracket 437 holding the calling roller 436 and the auxiliary bracket 439, and the elastic force of the tension spring described above, and the sheet feeding unit 406 is moved downward (FIG. 10 (a)). Eventually, the call roller 436 causes the uppermost sheet 9 on the sheet stacking tray 246.
8, the sheet feeding unit 406 continues to descend (FIG. 10B), and the position of the calling roller 436 at the lower limit position 444 with respect to the sheet feeding unit 406 starts moving toward the upper limit position 445. Eventually the calling roller 43
The filler 438 of the bracket 437 supporting the sheet 6 cuts off the sheet upper limit detection sensor 480 and
6 is stopped and the sheet can be fed (FIG. 10C).

When a large number of sheets are fed one by one from the sheet stack 99 on the sheet stacking tray 246 by the sheet feeding unit 406, the sheet height (stacking height) 92 on the sheet stacking tray 246 becomes equal to the number of fed sheets. It decreases in proportion. In response to this, the position of the calling roller 436 with respect to the paper feeding unit 406 is lowered, and the filler 438 of the bracket 437 holding the calling roller 436 that has cut the sheet upper limit detection sensor 480 cannot be cut off. Then, the moving motor 410 that moves the paper feeding unit 406 rotates, and the height position of the paper feeding unit 406 is changed to the calling roller 4
The filler 438 of the bracket 437 holding the sheet 36 lowers and stops the sheet upper limit detection sensor 480 again.

By repeating the above operation, the positional relationship between the uppermost sheet 98 on the sheet stacking tray 246 and the sheet feeding unit 406 is maintained within a certain range in which sheets can be fed.

The structure of the pressure lever portion is as follows.

The rotation centers 458 and 463 of both the pressure levers of the pressure lever portion 453 are in the pressure lever operable range 4
By providing on the parallel line of the intermediate position 455 of 54,
When the pressure levers 457 and 461 are rotated by a certain amount, the vertical movement error of the action points 459 and 462 is minimized (FIG. 12B). Both pressure levers 457, 461
From the rotation centers 458 and 462 to the action points 459 and 463
It is composed of two types of levers 457 and 461 having the same shortest distance to. The rotation centers 458 and 462 of the two pressure levers are fan-shaped gears 460 and 465 having the same module and the same reference pitch circle diameter, respectively, which have the same circular arc center, and the pressure drive levers 457 side are fan-shaped. On the side of the pressure driven lever 461, the fan-shaped driven gear 465 moves from the center of the pressure driven lever 462 to the lever of the pressure driven lever 461 so that the drive gear 460 is located outside the line connecting the lever center 458 and the action point 459. It is fixed so as to be inside the line connecting the center 462 and the action point 463 (FIG. 12).

Between the two front and rear pressure levers 457 and 461, both fan-shaped gears 460 and 465 mesh with each other, and the rotation center 4 of the pressure drive lever 457 and the pressure driven lever 461 is engaged.
58, 462 and the lines connecting the two action points 459, 463 are parallel to each other, and the fan-shaped gears 460, 46 of both
5, the intermediate gears 466 are attached one by one so that they can rotate freely when they are not meshed with each other.
56 is rotationally driven, and the fan-shaped gear 465 on the pressure driven lever 461 side is rotated via the fan-shaped gear 460 on the pressure driving lever 457 side and the intermediate gear 466 to drive the pressure-driven driven lever 461 by pressure. The lever 457 is rotated at the same angle and speed. In FIG. 11, reference numeral 46
Reference numeral 9 is a double feed prevention plate. In addition, the pressure drive lever shaft 456
As shown in FIG. 13, a worm wheel 467 is mounted on the shaft, the rotation of the dedicated drive motor 470 is transmitted from the worm 464 to the worm wheel 467, and the rotation is transmitted from the worm wheel 467.

Action points 459 and 463 of the two pressure levers
A pressure holding plate 468 is rotatably attached at the same center distance as the center distance between the rotation centers of the two pressure levers. Therefore, two pressure levers 457, 461
Even if is rotated, the pressure holding plate 468 moves in parallel while maintaining the initial angle. The pressure levers 457 and 461 are driven by the dedicated drive motor 470 as shown in FIG. 13 as described above, and are moved by the same amount as the paper feeding unit 406.
The pressure holding plate 468 rotates so as to move in a direction opposite to the direction in which the paper feeding unit 406 moves, and the pressure lever 45 is rotated.
The pressure holding plate 468 attached to the tip of the 7,461 is raised.

The sheet feeding unit 406 supplies one sheet at a time to the image forming apparatus 2 from the sheet storage section 270 in the sheet feeding apparatus 1 in the different size multi-stage sheet feeding system as described above. Feeding unit 406 to cover
Must be able to move smoothly in the vertical direction and accurately move from another place to a predetermined position. Therefore, the guided members 433 and 43, which are low friction members, are provided before and after the paper feeding unit.
4 is attached from the sheet feeding unit main body 431 via the arm 432 (FIGS. 16 and 24), and the guide rails 403, 434 are arranged so that the front and rear guided members 433, 434 are fitted to the main body skeleton 401 with a small gap. By providing 404 at the front and rear (FIG. 25), the paper feeding unit 406 can be smoothly moved within the regulated range (FIG. 21). Further, a moving motor 410 for accurately moving the paper feeding unit 406 in the vertical direction is attached to the main body skeleton 401 via a motor mounting bracket 413, and the moving motor 410 and the paper feeding unit 406 are suspended by pulleys 411 and 414. It is connected and moved by two cables 415 in front and rear (FIGS. 16 and 17).

Between the sheet feeding unit 406 in the sheet feeding device 1 and the right exterior 405, an intermediate feeding unit for feeding the sheet sent from the sheet feeding unit 406 into the image forming apparatus 2 is provided. There is. As shown in FIGS. 20 and 21, this intermediate conveying means is composed of three electrostatic conveying belts 41 having a wide width.
9, a driving roller 417 provided below, a charge eliminating roller 418 and a charging charger 420 provided above, and a main body skeleton 40 for holding the sheet feeding unit 406.
A vertical transport unit 416, which is fixed to No. 1 and includes a drive motor 407 that drives the paper feeding unit 406, is provided. Reference numeral 16 is a front cover.

The main body skeleton 401 is a structure 40 having four sides.
A right exterior 405 is fixedly formed on the sheet feeding device 2, and is attached by hinges 421 at two positions above and below the paper feeding device 1 so as to be openable and closable. Further, on the front side of the right exterior 405, a handle 422, a hook (not shown) attached to the handle, and a lock portion (not shown) for locking the hook are provided. A sheet feeding unit opening / closing section 400 is formed by these.

The paper feed unit opening / closing section 400 is always locked by a pulling spring (not shown) via a lever (not shown) to lock the hook attached to the handle 422 so that it cannot be opened and closed from the outside. But,
(1) When a malfunction occurs due to some cause while moving the sheet in the sheet storage section to another sheet storage section,
(2) While the sheet is being fed from the sheet feeding device to the image forming apparatus,
When a paper feed conveyance error occurs due to some cause,
(3) In the image forming apparatus or the automatic document feeder, when a malfunction occurs due to some cause, a solenoid (not shown) directly connected to the lever operates to unlock the hook and open the sheet feeding unit opening / closing unit 400. To enable.
The paper feeding unit 4 is used except when the above three problems occur.
The opening of 06 is prevented to prevent a user or the like from causing a malfunction. Further, when the above-mentioned three problems occur, the sheet generally exists in the conveyance path, so that the sheet must be removed. Therefore, the user pulls the handle 422 of the sheet feeding unit opening / closing unit 400 to open the sheet feeding unit opening / closing unit 400 in one step, and the subsequent processing can be performed quickly, so that the original copy operation can be immediately returned. Further, since it is possible to replace consumable parts of the paper feed unit 406 and the vertical conveyance unit 416 by a service person or the like in the same manner, it is possible to shorten the time which is a standard of the labor cost borne by the company or the user, and the cost is reduced. Contribute to reduction.

In the different size multi-stage paper feeding system, when the sheets in the arbitrarily selected sheet storage unit 270 are fed to the image forming apparatus 2 one by one by the paper feeding unit 406, the sheets in the sheet storage unit 270 are supplied. Since the stacking tray 246 remains fixed in the vertical direction, the paper feeding unit 406 changes the vertical position according to the remaining amount of sheets on the tray. Separately, the sheet storage portion 270 is provided with sheet regulation walls on the front and rear ends of the sheet in the sheet feeding direction, and on four sides in total on both sides parallel to the sheet feeding direction so that the sheets on the tray are accommodated within a predetermined range. There is. However, in this embodiment, since the sheet storage portion 270 is not provided with the sheet leading end reference wall, the sheet leading end reference wall 493 is provided on the sheet feeding unit 431 side.
Are provided (FIG. 14, FIG. 22, FIG. 23). The sheet leading end reference wall 493 is provided on the sheet storage section 270 side of the separation roller section 450 and on the lower separation roller 452 side of the separation roller section 450. However, in the paper feeding unit 406, there are a calling roller 436, a feed roller 451 and a separation roller 452 which cannot maintain their original shape due to wear and deterioration over time, and the quality of each of these rollers is deteriorated due to wear and deterioration. When you are not satisfied,
It is desired that the new roller can be easily replaced in a short time. However, the sheet leading end reference wall 4
By providing 93, the circumference of the separation roller is blocked, so that when the quality cannot be satisfied due to wear or deterioration, it cannot be easily replaced. Therefore, as shown in FIG. 22, a fulcrum 489 is provided at the bottom of the sheet leading end reference wall 493, and the fulcrum 489 is rotatably supported by the sheet feeding unit main body 431, and the sheet leading end reference wall 493 is made of a magnetic material. Then, a magnet 490 is provided in the portion of the sheet feeding unit body 431 corresponding to the upper portion of the sheet leading end reference wall 493. In this case, the sheet front end reference wall 493 and the magnet 4
The relationship with 90 is that when the sheet leading end reference wall 493 is in close contact with the magnet 490, the sheet bundle 99 stored in the sheet storing portion 270 is regulated, and when the sheet leading end reference wall 493 is separated from the attraction of the magnet 490, It is designed to fall toward the anti-separation roller side. The rotation support structure between the sheet leading end reference wall 493 and the sheet feeding unit main body 431 is such that the sheet leading end reference wall 493 is the sheet feeding unit main body 4
Since it suffices to be rotatably supported with respect to 31, various changes in design are possible.

With this configuration, when the separation roller 452 is replaced, the sheet leading end reference wall 493 is used.
Of the sheet leading end reference wall 49
By separating 3 from the magnet and rotating it around the fulcrum 489, the separation roller 450 is exposed so that replacement work can be performed easily.

In the case of not being rotatable in this way, as shown in FIG. 23, the sheet front end reference wall 493 is attached to the sheet feeding unit main body 431 by the screw 491 and can be easily removed when the separation roller 450 is replaced. You may leave it like this.

Next, the movement operation of the paper feeding unit will be described.

Since one sheet feeding unit 406 covers all the sheet storage portions 270a to 270a in the sheet feeding device 1, it is necessary to detect the position when moving up and down. Therefore, the sheet feeding unit opening / closing unit 400 is provided with one filler 494 for each stage, and the sheet feeding unit 406 is provided with a sheet feeding unit position detection sensor 492 so that the sensor 492 from the lowermost stage which is the home position is provided. Filler 49
The position of the paper feeding unit 406 is recognized based on the number obtained by cutting 4 (FIG. 16).

Further, regarding the positional relationship between the sheet storage portion 270 and the sheet feeding unit 406 when the sheet feeding unit position detection sensor 492 cuts off the filler 494, the calling roller 436 is set to the lower limit position 444 (FIG. 10A). ), And a filler 494 for the sheet feeding unit position detection sensor 492 of the sheet feeding unit 406 so that the calling roller 436 does not touch the uppermost sheet 98 and a certain constant height common to all the stages is maintained.
Are provided (FIG. 16).

At the bottom of the home position, another filler 49 is placed just before the filler 494 at the regular position.
4 is attached and the paper feed unit position detection sensor 492 is turned off earlier than the regular sensor on time,
It informs that the place where the next filler 494 is cut is the home position. A timing chart for this detection is shown in FIG.

The remaining amount of sheets in each sheet storage section 270 is
When raising the pressure holding plate 468 of the pressure lever portion 453 by the same amount as the movement amount of the sheet feeding unit 406 lowered from the standby position of that stage until the sheet upper limit detection sensor 480 of the calling roller portion 435 is turned on, The encoder 47 provided in the drive unit uses the amount by which the pressure drive lever shaft 456 is rotated.
1 is used and is detected by the remaining sheet amount detection sensor 482 (FIG. 13). Regarding the mode in which the pressure lever portion 453 of the sheet feeding unit 406 is not used at the time of sheet feeding, the sheet feeding unit 406 is lowered from the standby position of that stage until the sheet upper limit detection sensor 480 of the calling roller portion 435 is turned on. The movement amount is detected by the paper feeding unit position sensor 492 using the encoder 412 attached to the drive shaft 413 from the paper feeding unit moving motor 410 via the gear train (FIG. 17).

Next, the structure, operation and control related to the movement of the sheet will be described.

In the sheet feeding device 1, since the sheet replenishing port is located at the uppermost one position, the sheet is movable between the trays (sheet accommodating portions 270) from top to bottom. In this embodiment, the sheet moving means also serves as the sheet feeding means, so that space saving and cost reduction are realized.

The sheet replenishing operation at the sheet end will be described with reference to the drawings.

Since the first sheet storage portion 270a is a tray for replenishing sheets, basically no sheets are set on the tray. Therefore, a sheet replenishing method when the sheet end occurs in the second to ninth trays will be described.

First, FIG. 26 shows the sheet storage portion 2 of the sixth stage.
70f shows the state of the seat end. When the seat end is reached in this way, the end fence 350 returns to the home position. Next, as shown in FIG. 27, the sheet feeding unit 406 moves up to the sheet storage unit 270e in the fifth stage. The pressure holding plate 468 is pulled down to the bottom. From this state, as shown in FIG. 28, the sheet stack tray 246 of the fifth stage is moved in parallel from the standby position to the paper feeding position. In this case, the sheet feeding position means a position where the sheet comes into contact with the sheet leading end reference wall 493. Then, the pressure holding plate 468 rises while the paper feeding unit 406 descends, and the sheet bundle 99 is held by the calling roller 436 and the pressure holding plate 468 at a predetermined pressure (FIG. 29). After the sheet bundle 99 is held in this way, the fifth-stage sheet stack tray 246 starts parallel movement from the paper feed position to the retracted position. At the same time, the sheet feeding unit 406 holds the sheet bundle 99 as shown in FIG.
The descending movement starts from the sixth step to the sixth step. At this time, the sheet feeding unit 406 and the sheet stacking tray 246 in the fifth stage move at a preset relative speed so that the sheet bundle 99 moves smoothly, and the sheet bundle 99 moves the sheet stacking unit 270f in the sixth stage. When the movement is completed, the paper feeding unit 406 stops (FIG. 31).

The sheet feeding unit 406 stops moving and then rises, and the pressure holding plate 468 descends. As a result, the holding of the sheet bundle 99 is released as shown in FIG. Then, the sheet stack tray 246 of the fifth sheet storage unit 270e moves to the standby position, and the end fence 350 moves to the home position. On the other hand, the end fence 350 of the sixth-stage sheet storage portion 270f moves to the rear end of the sheet bundle 99, and further, the sixth-stage sheet stack tray 24
6 moves in parallel with the sheet bundle 99 from the sheet feeding position to the standby position as shown in FIG. When the setting of the bundle of sheets 99 in the sheet storage portion 270f is completed in this way, the sheet feeding unit 406 causes the sheet storage portion 270 of the fourth stage to operate.
Ascends to d (FIG. 34). Then, the same operation is performed for the fourth-stage sheet storage portion 270d, and this operation is repeated until the second-stage sheet stacking tray 246 is emptied and is stacked in the first-stage sheet storage portion 270a. The sheet bundle 99 is moved to the second-stage sheet storage portion 270b, and the sheet replenishing operation is ended.

Next, the relationship between the control modes of the image forming apparatus according to the embodiment will be described. First, the basic configuration of the system will be described.

35 and 36 are block diagrams of the control system of the image forming apparatus according to the embodiment.
Two control systems.

In FIG. 35, the control unit (controller 6
Reference numeral 00) is a central processing unit (hereinafter referred to as "CPU") 601, which constitutes a microcomputer for controlling the main body of the copying machine, a timer 602, an RO for storing fixed data such as program data for operating the CPU 601.
Volatile RAM 60 that temporarily stores temporary data such as M603, set flags for various modes, set number of sheets, and binding margin size, and loses data when the power is turned off
4. Non-volatile RAM 605 that stores process setting data, logging data such as the number of jams, the number of serviceman calls, the number of sheets passed, and the size data of each sheet storage unit, and the data is not lost even when the power is turned off, CPU
An I / O 606 that controls the interface between the control unit 601, the operation unit 610, the copy process unit 613, the paper feed control unit 620, and the sensor unit 630 controls the copy sequence based on a control program stored in the ROM 603.

Further, the CPU 601 has an operation unit 610 that detects various displays and various input information from the operator via the I / O 606, a copy process unit 613 that performs image formation such as charging and development, a paper feed control unit 620, and various types. It is connected to a sensor unit 630 connected to various sensor groups for detecting copy information, machine status information, and the like.

The operation unit 610 is a display unit 611 such as a CRT display or LCD for displaying various messages to the operator, and a key input unit 612 for detecting various input information (print key, mode key, etc.) from the operator.
Thus, the control output from the copying process unit 613 is sent to each unit 614 that executes the copying process including the above-described charging charger 8 and the developing device 9 and controls them.

Further, as shown in FIG. 36, the paper feed controller 62
0 is a paper feed unit drive unit 621 that drives a paper feed unit moving motor that moves the paper feed unit up and down, an end fence drive unit 622 that drives an end fence drive motor that moves an end fence, and a separation unit in the paper feed unit.
A paper feed / transport drive unit 623 that drives a paper feed / transport drive motor that operates each roller and an electrostatic transport unit related to transport,
A tray drive unit 624 that drives a tray drive motor that covers the movement of the tray, and a pressure lever drive unit 625 that drives a pressure lever drive motor that raises the pressure lever at the time of feeding and shifting the sheet to the lower stage. , An end fence drive unit 626 that drives an end fence drive motor that moves the side fence. Further, the outputs of various sensor groups of the sensor unit 630 are set to I / O6
The CPU 601 detects this via 06 and executes the copy sequence based on the control program stored in the ROM 603. At that time, regarding the paper feed control such as paper feed and paper end, various signals such as a paper feed operation signal and a paper end processing signal are sent from the CPU 601 to the I / O 60.
It is sent to the paper feed control unit 612 via 6. The paper feed control unit 612 sends a drive signal to each drive unit (not shown) based on these signals and controls the drive signals to perform processing such as paper feed and paper end. In addition, this CPU6
01 controls a predetermined control described later, such as detecting a sheet storage unit that stores the most frequently used sheet from the sheet size data stored in the nonvolatile RAM 605.

Further, the sensor section 630 detects the presence / absence of the sheet at the stage at the time of feeding the sheet end detecting sensor 48.
1. A sheet remaining amount detection sensor 482 that detects the remaining amount of the sheet in the stage being fed in several stages, and a sheet feeding unit position detection sensor that detects the number of the fed sheet by counting from the home position 492, a sheet leading edge detection sensor 483 that checks whether the sheet is fed correctly when feeding the sheet, a sheet upper limit detection sensor 480 that detects the upper limit of the sheet bundle of the tray, and an end fence that detects the position of the end fence A position detection sensor 357, a sheet detection sensor 394 that detects the presence / absence of a sheet when the drawer tray is taken in and out, a tray opening amount detection sensor 631 that detects an open amount when the drawer tray is pulled out in combination with an encoder, and a home position of the tray. Tray standby position detection sensor 632 to detect, a person to detect the presence of the operator Detection sensor 633, the tray sheet feed position detecting sensor 634 for detecting the feed position of the tray, and is configured from the tray driving unit position detecting sensor 635 and the like.

In the above system, a series of CPs
The determination operation of U601 may be stored in the ROM 603 and / or the non-volatile RAM 605 in advance. This also applies to each control operation described later.

The sheet size detection is performed by the first-stage sheet storage section 270a. The lateral size of the sheet is detected by the end fence 350. First, in this detection, the end fence 350 is moved to the home position, and at this time, the filler on the lower side of the rack (not shown) keeps cutting the end fence position detection sensor 357 while moving, and is set from the number of cutting the sensor 357. The lateral size of the sheet is calculated, and the sheet size is detected by the CPU 601.

Table size (hereinafter "tbl-siz"
e ". ) (I) is a table for storing sheet size data, replenishment date data, and paper type data as shown in FIG. 37, and tbl-size (i) is a nonvolatile RA.
It is provided on the M605, and the data is retained even when the power of the apparatus main body is turned off. Further, in this table, when a sheet is set in the first sheet storage section 270a, the sheet size is detected in the first sheet storage section 270a as described above, and the size data is registered. Further, when the sheet bundle 99 moves between the sheet storage units 270, t
The sheet size data and the like of bl-size (i) are also changed according to the movement of the sheet bundle 99.

The sheet size detection and sheet size registration shown in FIG. 38 will be described below with reference to the flowchart. In the following description of the flow chart, like S (38) 0 step, the corresponding figure number is shown in parentheses after S representing a step, and the corresponding step is clarified.

First, in step S (38) 0, the sheet bundle 99 from the i-th stage sheet storage section to the i + 1-th stage sheet storage section
Is determined by the CPU 601. If there is no movement in this determination, the process proceeds to step S (38) 2, and the CPU 601 determines whether or not there is a sheet supply in the first-stage sheet storage portion 270a. If there is no sheet replenishment in this determination, it is out of the target of this mode, so the process returns and exits from this mode. If the sheet is replenished, the process proceeds to step S (38) 3 steps or less, and t
bl-size (i) has a first stage sheet storage portion 270a.
Register the sheet size data etc. detected in.

Next, in step S (38), it is determined whether or not there is a request for sheet replenishment day registration. Also, S
(38) In step 6, it is determined whether or not there is a registration request for the paper type data of the supply sheet. Then, depending on these conditions, S (38) 5, S (38) 7, S (3
8) Each step of 8 is executed. That is, tbl-s
37, the sheet size data and the replenishment date data are tbl-size (1), which is the table data of the first-stage sheet storage unit of the size (i).
-Registered as in the size (1) column. Then, when the registration of each data is completed, this mode is ended.

On the other hand, when it is determined in step S (38) 0 that there is a movement of the sheet from the i-th sheet storage section to the i + 1-th sheet storage section, it is determined that there is movement, that is, the Since the i + 1-th sheet storage unit is the paper end, when the sheet bundle 99 moves between the sheet storage units, the predetermined sheet size data of tbl-size and the like are also updated according to the sheet movement. (1 step of S (38)). FIG. 37 shows how tbl-size data is updated.
Shown in (a) and (b). Temporarily, the second stage sheet storage unit 27
When the sheet is moved from 0b to the third-stage sheet storage portion 270c, the data of tbl size (2) is the second data.
Since the corrugated sheet storage portion 270b has become empty, it is cleared to 0.

By this operation, even if the sheet is moved between the sheet storage units, the predetermined sheet size data of tbl-size and the like are also updated according to the sheet movement. The sheet size of the sheet storage unit 270 is the data table tbl-si.
It can be correctly recognized by referring to ze.

The control of the position of the paper feeding unit is different after the copying is completed, when the copy is disclosed, and when the sheet is selected manually.

First, the control of the position of the paper feeding unit 406 will be described with respect to the position after the copying operation is completed.

FIG. 39 is a flowchart showing the control procedure of this control. First, in the control procedure of FIG. 39, S
(39) In step 0, the CPU 601 determines whether or not the copy operation is currently in progress. If it is determined that the copy operation is not in progress, the control is ended because it is out of the scope of this control. Conversely, when the copy operation is in progress, the CPU 601 determines in step S (39) whether or not the copy operation is completed. If the copy operation is still in progress, the copy operation is continued until the copy operation is completed. When the copy operation is completed, the process proceeds to step S (39) 2.

In step S (39), the CPU 601 detects in what stage the sheet feeding unit 406 is currently located (i-th stage), and in step S (39) 3, the most frequently used sheet is used. Non-volatile RAM 605 size
Detected from the usage frequency data stored in
A non-volatile RA indicating the number of stages of the sheet storage unit 270 that stores the sheet of the sheet size
It is detected from the size data stored in M605 (j-th stage). When both are detected, S (3
9) In step 4, the CPU 601 determines whether the i-th stage and the j-th stage are the same. When the i-th stage and the j-th stage are the same, the control is ended without doing anything, and the i-th stage is executed. When the tier is different from the j-th stage, the CPU 601 controls the sheet feeding unit driving section 621 to move the position of the sheet feeding unit 406 to the j-th stage in preparation for the next copying operation, and ends.

In this embodiment, the sheet feeding unit 406 is moved to the position of the sheet storing section that stores the sheet size of the sheet that is most frequently used. It may be moved to the sheet storage portion 270e of the portion (fifth stage in this embodiment).

The size of the sheet stored in the sheet storage portion 270 is obtained as described above, and the nonvolatile R
The sheet size is stored in the tbl-size of the AM 605, but the sheet size after image formation is detected by, for example, the transport device 13.
Alternatively, a known sensor may be provided around the sheet storage unit 270 to detect the size of the sheet after the image transfer, or the sheet size may be detected after the sheet is stored in the sheet storage unit 270. A known technique is introduced to detect these sheet sizes.

By controlling in this way, the position of the sheet feeding unit 406 after the completion of copying is automatically moved to the sheet storing section storing the sheet size of the sheet size which is most frequently used. The number of movements of the paper feeding unit 406 during the copy operation is reduced, which improves productivity.

The control of the position of the paper feeding unit 406 at the start of copying is as follows. This control will be described with respect to the position when there is any copy start request.

FIG. 40 is a flow chart showing the procedure relating to the above control. In this control, first, S (40)
In step 0, the CPU 601 detects any copy start request, that is, an input to the key input unit 612 of the operation unit 610 in the standby state, or an original set detection (not shown) for setting an original on the automatic document feeder 3. The access to the main body of the apparatus is detected by a sensor, or the opening / closing of the automatic document feeder 3 is detected by a pressure plate opening / closing detection sensor (not shown). The CPU 601 determines whether or not there is this, and a copy start request is made. If there is not, there is a waiting state for some copy start request.

If a start request is input, S (4
0) CP at which step of the sheet feeding device 2 the position of the sheet feeding unit 406 when a copy start request is made in one step
The sheet size most frequently used in step S (40) 2 is detected by U601 (i-th stage).
The size stored in the non-volatile RAM 605, which is detected from the usage frequency data stored in the AM 605, and which stage of the sheet storage unit 270 storing the sheet of that sheet size is in the non-volatile RAM 605. It is detected from the data (jth stage). Then, in step S (40) 3
The CPU 601 determines whether or not the tier is the same as the jth stage, and when the ith stage and the jth stage are the same, the control is ended without doing anything, and the ith stage and the jth stage are terminated. , The CPU 601 controls the sheet feeding unit driving section 621 to move the position of the sheet feeding unit 406 to the j-th stage in preparation for the copy operation.

In this embodiment as well, instead of moving the sheet feeding unit 406 to the position of the sheet storage unit that stores the most frequently used sheet size sheet, it may be moved to the central sheet storage unit. good.

With this control, the position of the paper feed unit 406 is automatically moved to the sheet storage unit that stores the sheet size of the sheet size that is most frequently used when there is any copy start request. The number of movements of the paper feeding unit 406 during the copy operation is reduced, which improves the productivity.

The control of the position where the operator manually selects the sheet size on the operation unit 610 of the image forming apparatus main body is as follows.

FIG. 41 is a flow chart showing the control procedure in this control. In this control, first, S (4
1) In step 0, the operator inputs and sets the sheet size to be used for copying in the key input unit 612 of the operation unit 610, and in step S (41), the nonvolatile RAM
The sheet size stored in each sheet storage unit 270 is detected from the sheet size data stored in 605, and the CPU
In step 601, it is determined whether the sheet size designated by the operator is stored in any sheet storage section 270. When the sheet of the set sheet size is not stored in any of the sheet storage units 270, the process jumps to the sheet replenishment control routine, and the first-stage sheet storage unit 270a.
To replenish the seat.

FIG. 42 is a flow chart showing the control procedure of the sheet replenishment control.

In step S (42) 1-1, first, the fact that there is no set sheet size is displayed on the display unit 611 of the operation unit 610, and the operator is informed accordingly. Then, in step S (42) 1-2, the first-stage sheet storage unit 2
The presence or absence of the sheet 70a is detected by the sheet detection sensor 394 provided in the first-stage sheet storage portion 270a, and CP
The presence / absence of a sheet in the first-stage sheet storage portion 270a is determined by U601. Here as well, the first-stage seat storage portion 270
If there is no sheet in a, the first stage sheet storage portion 270a
It is displayed on the display unit 611 of the operation unit 610 that there is no sheet in the sheet, the operator is informed, and the sheet is replenished.

If there is a sheet in the first-stage sheet storage portion 270a, the process proceeds to step S (42) 1-3 to detect the sheet size from the sheet size data stored in the non-volatile RAM 605, and the CPU 601 1
It is determined whether or not the sheet size of the corrugated sheet storage unit 270a matches the sheet size set by the operator. Here, if the sheet sizes of the first-stage sheet storage portion 270a do not match, the first-stage sheet storage portion 27
Display section 6 of the operation section 610 to remove the sheet from the sheet 0a.
Displaying 11 indicates to the operator that the sheet size is different and prompts the removal of the sheet. Also,
When the sheet sizes of the first-stage sheet storage portion 270a match, this routine is ended and the process returns to the sheet feeding unit position control routine.

Next, in step S (41) 2, whether or not the sheet size matching the sheet size set by the operator is stored in any sheet storage unit 270 is stored in the nonvolatile RAM 605 for each sheet. It is detected from the sheet size data of the storage section 270, and the CPU 601 determines whether or not there are a plurality of stages. If there is only one sheet storage unit 270 that stores a sheet having a sheet size that matches the sheet size set by the operator, there is no room for selection.
Which sheet storage unit 270 is stored is detected from the sheet size data stored in the nonvolatile RAM 605 (kth stage), and the CPU 601 controls the sheet feeding unit driving unit 621 to control the sheet feeding unit 406. The position is moved to the kth stage sheet storage portion 270k. On the contrary, if there are a plurality of sheet storage units 270 that store sheets having a sheet size that matches the sheet size set by the operator, the process proceeds to step S (41) 3, where the current position of the sheet feeding unit 406 is set to the CPU 601. (I-th stage). In step S (41), it is detected from the sheet size data stored in the non-volatile RAM 605 which stage of the sheet storage unit 270 stores the sheet having the sheet size matching the sheet size set by the operator. (J ₁ -j _{n th} stage; n ≧
2).

In step S (41), first, when the sheet storage section 270 is selected according to the movement distance, the sheet storage section selection routine according to the movement distance shown in FIG.
(43) In step 5-1, the distance (d _{1 to} d _n ; d ₁ =) between the i- _th stage and each of the j _{1 to} j _n-th sheet storage units 270.
| I−j _n |) is detected by the CPU 601 and S (4
3) In step 5-2, the CPU 601 detects the smallest _one of the distances d _{1 to} d _n (d _k ). Then, the process returns to the sheet feeding unit position control routine, and in step S (41) 6, the CPU 601 controls the sheet feeding unit driving unit 621 to move the sheet feeding unit to the kth sheet accommodating unit 270k corresponding to the minimum distance d _k. The position of 406 is moved.

When the sheet storage section 270 is selected in accordance with the remaining sheet quantity, the control jumps to the sheet storage section selection control routine based on the remaining sheet quantity shown in FIG. 44, and at step (5-1) of step S (44) j _{1 to} j _n. The remaining sheet amount of each sheet storage unit 270 of the tier is detected from the remaining sheet amount data stored in the nonvolatile RAM 605 (m _{1 to mn} ), and S (44) 5-2
The largest _one of the remaining amounts m _{1 to mn in} the step is the CPU 6
Detected by 01 (m _k ). Then, the process returns to the paper feed unit position control routine, and the CPU is operated in step S (41) 6
The sheet feeding unit driving unit 621 is controlled by 601 to move the position of the sheet feeding unit 406 to the k-th sheet storage unit 270k corresponding to the maximum remaining amount m _k .

By controlling as described above, when the operator manually selects the sheet size, the position of the sheet feeding unit 406 is automatically moved to the sheet storage section 270 that minimizes the movement distance. The movement time of the paper feeding unit 406 until the start is reduced,
This improves productivity. Further, by automatically moving the position of the sheet feeding unit 406 to the sheet storage unit 270 having the largest remaining amount of sheets, the sheet end during copying is reduced, which also improves the productivity.

Control of other positions of the paper feeding unit 406 will be described with respect to the position when the operator manually selects the sheet size. This control is performed in consideration of the sheet supply date.

FIG. 45 is a flow chart showing the control procedure of this control. In this control, first, S (45) 0
When the operator inputs and sets the sheet size to be used for copying in the key input unit 612 of the operation unit 610 in step, the nonvolatile RAM 605 is set in step S (45) 1.
Based on the sheet size data stored in each sheet storage unit 2
CPU 601 detects the sheet size stored in 70
Thus, it is determined in which stage of the sheet storage section 270 the sheet size designated by the operator is stored. When the set sheet size is not stored in any of the sheet storage units 270, the sheet supply control routine is skipped and the sheets are supplied to the first-stage sheet storage unit 270a. The supply control procedure is as shown in the flowchart of FIG.

Next, in step S (45) 2, it is stored in the non-volatile RAM 605 as to which stage of the sheet storage section 270 the sheet having the sheet size matching the sheet size set by the operator is stored. It is detected from the sheet size data of each sheet storage unit that is present, and the CPU (601) determines whether or not there are a plurality of stages. In this determination, if there is only one sheet storage portion 270 that stores the sheet size that matches the sheet size set by the operator, there is no choice, so which sheet storage portion 270 is stored. The sheet size data stored in the nonvolatile RAM 605 is detected (kth stage), and the CPU 601 controls the sheet feeding unit drive unit 621 to move the position of the sheet feeding unit 406 to the kth stage sheet storage unit 270k. Let vice versa,
When there are a plurality of sheet storage units 270 that store the sheet size that matches the sheet size set by the operator, the process proceeds to step S (45) 3, and the CPU 601 detects the current position of the sheet feeding unit 406 (the first position). i
Step).

In step S (45), the sheet size data stored in the non-volatile RAM 605 is stored in the non-volatile RAM 605 as to which stage of the sheet storage section 270 the sheets having the sheet size matching the sheet size set by the operator are stored. More detection (j ₁ -j _{n th} stage; n ≧ 2).
In step S (45) 5, when the sheet storage section 270 is selected according to the sheet supply date, the control jumps to the sheet storage section selection control routine according to the sheet supply date in FIG.
S (46) 5-1 first j ₁ to j _n-th stage of each sheet storage portion 270 of the sheet supply date (t ₁ ~t _n) replenishment date data sheets stored in the RAM605 nonvolatile at step Then, in step S (46) 5-2, the CPU 601 determines whether or not any of the sheet replenishment dates t _{1 to} t _n is older than the preset period. If there is no old one, the CPU 601 selects the sheet storage unit 270 by preferentially using the sheet storage unit 270 with a large remaining amount, and if there is an older one than the preset period, the oldest of them is selected. The sheet is detected by the CPU 601 (t _k ). Then, returning to the sheet feeding unit position control routine, the CPU 601 controls the sheet feeding unit driving section 621 in step S (45) 6 to feed the sheet feeding unit to the kth stage sheet storing section 270k corresponding to the longest period t _k. The position of 406 is moved.

When the sheet storage section 270 is selected according to the sheet storage section position, the control jumps to the sheet storage section selection control routine according to the sheet storage section position of FIG.
7) In step 5-1, the CPU 601 detects the position of each of the j _{1 to} j _n-th sheet storage units 270 (p ₁ to p
_n ), S (47) 5-2 step, sheet storage position p
Of the _{1 to pn,} the one located at the top is the CPU 60.
1 (p _k ). Then, the process returns to the sheet feeding unit position control routine, and the CPU 6 is operated at step S (45) 6.
01 controls the sheet feeding unit driving section 621 to control the k-th sheet accommodating section 270 corresponding to the uppermost p _k.
The position of the sheet feeding unit 406 is moved to k.

By controlling in this way, when the sheet size is manually selected by the operator, the position of the sheet feeding unit 406 is automatically set to the sheet storing section storing the oldest sheet according to the sheet replenishment date. The sheet is prevented from curling or absorbing moisture caused by leaving the sheet for a long period of time by moving the sheet, so that jams and wrinkles due to deterioration of the sheet can be reduced, thereby improving the stability and productivity of image formation. Also, by automatically moving the position of the sheet feeding unit 406 to the uppermost sheet storage portion, the amount of movement of the sheet is reduced even if the sheet end occurs during copying, which also improves productivity. .

When the automatic document feeder 3 is used, naturally, the control of the position of the paper feeding unit 406 also changes.
Hereinafter, the control of the position of the paper feeding unit when copying documents of different sizes using the automatic document feeder 3 will be described.

FIG. 48 is a flow chart showing the control procedure in this control. In this control, first, S (4
8) In step 0, the operator selects a plurality of sheet sizes to be used for copying from the key input unit 61 of the operation unit 610.
Set to 2 and set CP in step S (48)
The sheet sizes stored in the respective sheet storage units 270a are detected by U601, and it is determined in which stage of the sheet storage units 270 the sheets of the plurality of sheet sizes are stored. In this determination, if even one of the plurality of set sheet sizes is not stored in any sheet storage section 270, the process jumps to the sheet replenishment control routine,
Sheets are supplied to the first-stage sheet storage portion 270a. The control procedure for this sheet supply is as shown in the flowchart of FIG.

Next, in the non-volatile RAM 605, the non-volatile RAM 605 stores which stage of the sheet storage section 270a stores the sheet of the sheet size that matches the sheet size set by the operator in step S (48) 2. The CPU 60 detects from the sheet size data of each sheet storage unit 270 and determines whether at least one size is plural.
Judge by 1. If it is determined in this determination that there is only one sheet storage unit 270a that stores sheets having a sheet size that matches a plurality of sheet sizes set by the operator, there is no room for selection. 270 is stored in the non-volatile RAM 60
5 is detected from the sheet size data stored in each sheet storage portion 270 (kth stage, Lth stage), and S (4
8) Depending on which of the k-th and l-th sheet storage units 270k, 270l the sheet size to be used first among the plurality of sheet sizes jumped to 7 steps is stored by the CPU 601. The sheet feeding unit driving unit 621 is controlled to move the position of the sheet feeding unit 406 to the first sheet storage unit to be used.

On the contrary, when there are a plurality of sheet storage units 270 which store the sheet sizes matching the plurality of sheet sizes set by the operator for at least one sheet size, the process proceeds to step S (48) 3. The CPU 601 detects the current position of the paper feeding unit 406 (i-th stage). In step S (48), each sheet storage unit 270 stores in the non-volatile RAM 605 whether a sheet size matching a plurality of sheet sizes set by the operator is stored in any sheet storage unit 270. From the sheet size data (at least _{one of} j _{1 to} j _{n th} stage, h _{1 to} h _{m th} stage, m and n ≧ 2).

[0122] Then, S (48) in 5 step the j ₁ ~
The distance (d _{11 to} d _mn ; d ₁₁ = | j ₁ −h ₁ |) between each j- _th storage unit and each h _{1 to} h _m -th sheet storage unit is C
It is detected by the PU 601 and the smallest one of the distances d _{11 to} d _mn is detected by the CPU 601 in step S (48) 6 (d _kl ). In step S (48) 7, the sheet storage portion 270 of the kth stage and the 1st stage corresponding to this minimum distance d _kl.
which sheet storage unit 270k is the first sheet size to be used among the sheet sizes stored in k and 270l,
CPU60 depending on whether it is stored in 270 l
The sheet feeding unit driving unit 621 is controlled by 1 to move the position of the sheet feeding unit 406 to the first sheet storage unit 270k or 270l.

By controlling in this way, when copying documents of different sizes using the automatic document feeder 3, the sheets are arranged so that the distance between the sheet storage units storing different sheet sizes is minimized. Since the storage unit can be selected and the paper feeding unit 406 can be moved,
The movement distance of the paper feeding unit 406 during the copy operation is reduced, which improves the productivity.

[0124]

As is apparent from the above description, according to the first aspect of the present invention configured as described above, after the series of image forming operations is completed, the recording sheet that is most frequently used is accommodated. Since the paper feed unit is moved to the position corresponding to the stack and waits for the next image forming operation, the number of times the paper feed unit is moved at the time of the next image formation is reduced. Is the shortest. Therefore, the overall time required for image formation on the recording sheet is shortened, and the productivity is improved.

According to the second aspect of the present invention, when the image forming start is inputted, the recording sheet accommodating tray which is most frequently used from the sheet feeding position which is located at the time of the input. Since the sheet is moved to the position corresponding to the above and waits for the start of sheet feeding, the number of movements of the sheet feeding unit is reduced at the start of copying, whereby the same effect as the invention according to claim 1 can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram illustrating an entire system of an image forming apparatus according to an embodiment.

FIG. 2 is a perspective view of the image forming apparatus showing a state in which a drawer tray of the paper feeding device is pulled out.

FIG. 3 is a perspective view of the image forming apparatus showing a state of a sheet feeding (drawing) tray in a conventional sheet feeding device.

FIG. 4 is a front view of the image forming apparatus showing a home position which is a reference when the sheet stacking tray is moved.

FIG. 5 is a perspective view of an image forming apparatus showing an example of an automatic loading drawer tray.

FIG. 6 is a perspective view of relevant parts showing a state in which an automatic loading drawer tray is pulled out.

FIG. 7 is a perspective view showing a pipe-shaped structure of an automatic loading type sheet drawer tray.

FIG. 8 is a front view showing a schematic configuration of a paper feeding unit.

FIG. 9 is a perspective view showing a calling roller unit of a paper feeding unit and a related mechanism thereof.

FIG. 10 is an operation explanatory diagram illustrating an operation of holding the sheet bundle of the sheet feeding unit.

FIG. 11 is a perspective view showing a pressure holding plate of the paper feeding unit and its related mechanism.

FIG. 12 is an operation explanatory view showing the operation of the pressure lever.

FIG. 13 is a perspective view showing a main part of a drive mechanism of a pressure lever.

FIG. 14 is a front view showing a main part of a sheet leading edge aligning mechanism.

FIG. 15 is a plan view showing a main part of a sheet leading edge aligning mechanism.

FIG. 16 is a side view showing a schematic configuration of a paper feeding / conveying unit.

FIG. 17 is an enlarged perspective view of an essential part showing an essential part of a paper feeding / conveying unit.

FIG. 18 is a timing chart showing the detection timing of the sheet feeding unit position detection sensor.

FIG. 19 is a schematic configuration diagram showing a mechanism near a seat end detection sensor mounting position.

FIG. 20 is a perspective view showing a main part of a drive mechanism of a paper feeding unit.

FIG. 21 is a perspective view of a main part showing a configuration of a sheet feeding / conveying unit.

FIG. 22 is a front view of a main portion showing the configuration of a separation roller unit.

FIG. 23 is a perspective view of a main part showing a configuration of a separation roller part.

FIG. 24 is a side view showing the outline of the support mechanism of the paper feeding unit.

FIG. 25 is a front view showing the outline of the support mechanism of the paper feeding unit.

FIG. 26 is an operation explanatory view showing the sheet moving operation.

FIG. 27 is an operation explanatory view showing the sheet moving operation.

FIG. 28 is an operation explanatory view showing the sheet moving operation.

FIG. 29 is an operation explanatory view showing the sheet moving operation.

FIG. 30 is an operation explanatory view showing the sheet moving operation.

FIG. 31 is an operation explanatory view showing a sheet moving operation.

FIG. 32 is an operation explanatory view showing the sheet moving operation.

FIG. 33 is an operation explanatory view showing the sheet moving operation.

FIG. 34 is an operation explanatory view showing the sheet moving operation.

FIG. 35 is a block diagram showing a part of a basic system of the image forming apparatus according to the embodiment, which is integrated with FIG. 36 to construct one system.

FIG. 36 is a block diagram showing another part of the basic system of the image forming apparatus according to the embodiment, which is integrated with FIG. 35 to construct one system.

FIG. 37 is a diagram showing a table that stores sheet size data, replenishment date data, and paper type data in the image forming apparatus according to the embodiment.

FIG. 38 is a flowchart showing a processing procedure for sheet size detection and sheet size registration in the embodiment.

FIG. 39 is a flowchart showing a control procedure when the sheet feeding unit is moved to the sheet storage section having the highest frequency of use after completion of copying.

FIG. 40 is a flowchart showing a control procedure for moving the paper feed unit to the sheet storage section having the highest frequency of use when a copy start input is made.

FIG. 41 is a flowchart showing a control procedure of position control of the sheet feeding unit when the sheet size is set by the operator.

FIG. 42 is a flowchart showing a control procedure of a sheet supply control routine.

FIG. 43 is a flowchart showing a sheet storage unit selection routine based on a moving distance.

FIG. 44 is a flowchart showing a sheet storage unit selection routine based on the remaining amount of sheets.

FIG. 45 is a flowchart showing another control procedure of the position control of the paper feeding unit when the sheet size is set by the operator.

FIG. 46 is a flowchart showing a sheet storage section selection routine based on a sheet supply date.

FIG. 47 is a flowchart showing a sheet storage unit selection routine based on the tray position.

FIG. 48 is a flowchart showing a control procedure of position control of a paper feeding unit when the automatic document feeder is used.

[Explanation of symbols]

 1 Paper Feeding Device 2 Image Forming Device 3 Automatic Document Feeding Device 406 Paper Feeding Unit 435 Calling Roller 436 Calling Roller 453 Pressure Lever 468 Pressure Holding Plate 481 Sheet End Detection Sensor 484 Roller Drive 600 Controller (Controller) 601 central processing unit (CPU) 602 timer 603 ROM 604 RAM 605 non-volatile RAM 610 operation unit 611 display unit 612 key input unit 620 paper feed control unit 621 paper feed unit drive unit 623 paper feed / transport drive unit 625 pressure lever drive Part 630 sensor part

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technology display location H04N 1/00 108 C 7046-5C (72) Inventor Tamiya Akimoto 1-3-6 Nakamagome, Ota-ku, Tokyo No. In Ricoh Co., Ltd. (72) Inventor Jun Otaka 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd.

Claims (2)

[Claims] 1. An image forming apparatus comprising: a sheet feeding device in which a plurality of recording sheet storage stages are provided in a vertical direction, and the recording sheet is replenished only to one preset recording sheet storage stage. Is moved to one of the recording sheet storage stages other than the one preset recording sheet storage stage, and the recording sheet is picked up from the other recording sheet storage stage to the image forming means side of the image forming apparatus. A sheet feeding unit to be conveyed, a first sheet size detecting means for detecting the size of the recording sheet accommodated in the other recording sheet accommodating stage, and a size of the recording sheet detected by the first sheet size detecting means. And a second sheet size detection unit for detecting the size of the recording sheet for which image formation has been completed by the image forming unit. Means, a second storage means for storing the size of the recording sheet detected by the second sheet size detection means, and a sheet size with the highest image forming frequency based on the storage information of the second storage means. The most frequent recording sheet storage stage detecting means for detecting the most frequent recording sheet storage stage in which the recording sheets are stored, and the sheet feeding unit at a position corresponding to the most frequent recording sheet storage stage after completion of a series of image forming operations. An image forming apparatus comprising: a drive control unit that moves the image. 2. An image forming apparatus comprising a paper feeding device, in which a plurality of recording sheet storage stages are provided in a vertical direction, and the recording sheets are supplied only to one preset recording sheet storage stage. Is moved to one of the recording sheet storage stages other than the one preset recording sheet storage stage, and the recording sheet is picked up from the other recording sheet storage stage to the image forming means side of the image forming apparatus. A sheet feeding unit to be conveyed, a first sheet size detecting means for detecting the size of the recording sheet accommodated in the other recording sheet accommodating stage, and a size of the recording sheet detected by the first sheet size detecting means. A first storage unit for storing the image forming unit, an image formation start detecting unit for detecting an image formation start by the image forming unit, and a position of the sheet feeding unit. The position detecting means for detecting, the second sheet size detecting means for detecting the size of the recording sheet for which the image forming means has finished image formation, and the recording sheet size detected by the second sheet size detecting means. Second storage means for storing, and based on the storage information of the second storage means, the most frequent recording sheet for detecting the most frequent recording sheet storage stage in which the recording sheet of the sheet size with the highest image forming frequency is stored. When the image formation start is detected by the storage stage detection unit and the image formation start detection unit, the sheet feeding unit is moved from the sheet feeding position detected by the position detection unit to a position corresponding to the most frequent recording sheet storage stage. An image forming apparatus comprising: a drive control unit that moves the image.