JPH0480134A - Image forming device feeding device - Google Patents

Abstract

PURPOSE:To dispose a plurality of containing means in a reduced space by disposing the containing means in a plurality along the moving direction of an endless transfer means. CONSTITUTION:An endless transfer means 53 moves along a plurality of containing means 52, 52', 52' in order, and for feeding, part of the endless transfer means 53, or the whole body of it if necessary, moves additionally to transfer motion, where the endless transfer means 53 is pushed by a pressure means 58 for a contact means, the endless transfer means 53 gets in contact with a recording medium 77, the recording medium 77 is sucked by a suction force of the transfer means 53, and the recording medium 77 is fed from the containing means 52, 52', 52'' to be transferred to an image forming part. By action of the pressure means 58 at predetermined timings respectively for the containing means 52, 52', 52'', a plurality of recording mediums 77 are fed and transferred from the containing means 52, 52', 53'' one by one continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording medium feeding and conveying device in an image forming apparatus such as a copying machine, a laser printer, and a facsimile machine.

[Prior art]

In image forming apparatuses such as copying machines, it is known that a sheet-like recording medium such as a transfer paper fed by the friction of a rubber roller is conveyed by a pair of rubber rollers or a belt to an image forming position such as a transfer position by a photoreceptor. ing.

In such conventional recording medium feeding and conveying devices, in order to prevent multiple sheets of recording media from being fed overlappingly, a friction pad is combined with the rubber feeding roller, and a rubber reverse roller is used to reverse the rotation. In addition, corner claws are provided on the cassette that houses the recording medium.

However, conventional recording systems have problems such as jams and skewing during conveyance, and in addition to double feeding, conventional apparatuses also have problems with interoperability during feeding and conveyance.

Furthermore, the structure becomes more complex and the control becomes more complicated.
It is also costly, and the problems of simplifying the device and reducing costs remain unsolved.

In order to solve these conventional problems, an insulating endless belt is passed around almost all the conveyance systems in the copying machine, and the belt is charged with a charging device, and the paper stored in the paper feed tray is transferred to the heald. The paper is sent out by a feed roller installed on the same axis as the support roll, and the paper is electrostatically attracted to the rear belt, or the belt is brought into direct contact with the paper and electrostatically adsorbed and fed, and at the same time, the paper is delivered to the photoreceptor. For example, it is known in Japanese Patent Application Laid-Open No. 59-212856 that it is conveyed by a heddle to the transfer area to be transferred in contact with the transfer area.
No., JP-A-59-224858, JP-A-59-229
This method has been proposed in Publication No. 585 and the like.

Also, the paper feed section, registration section, transfer section, fixing section, and paper ejection section of the copying machine are connected in this order with one endless belt, and the endless belt is first attached to the copy paper held in the copy paper feed section. For example, Japanese Patent Application Laid-Open No. 139846/1984 proposes that the copy paper is brought into pressure contact with the copy paper by frictional force, and is conveyed to an image forming area after registration.

In the above-mentioned conventional technology, the conveyor belt can only feed paper from one paper feed tray.

In other words, in recent years when only one size of paper can be fed, copying machines are equipped with multiple paper trays or paper cassettes to accommodate paper of multiple sizes, and the paper feed - can be arbitrarily selected, but there is a problem that a large space is required for the paper feed tray.

In the above-mentioned conventional technology, when trying to use different types of paper, it is necessary to replace the paper in the paper feed tray or replace the paper feed tray containing the different types of paper each time. Therefore, there was a problem that the operability was extremely poor.

Furthermore, with the prior art, it has been impossible to continuously feed a plurality of sheets at almost zero intervals.

[Problem to be solved by the invention]

The present invention solves the above-mentioned conventional problems, makes it possible to accommodate multiple types of recording media in a small space, and allows recording media of arbitrary sizes to be fed from the plurality of storage means using an endless conveying means. Furthermore, it is an object of the present invention to provide a feeding device that exhibits a registration function without providing a separate registration means.

[Means to solve the problem]

The present invention solves the above-mentioned problem by providing an image storage system that includes a storage means for storing a recording medium on which an image is to be recorded, and an endless conveyance means for sucking and transporting the recording medium from the storage means to an image forming position by an image information holding means. In the feeding device of the forming device,
A plurality of the storage means are arranged in the moving direction of the endless conveyance means, and a contact means movable up and down is provided at a position where a leading edge of the recording medium of each storage means comes into contact. This problem has been solved by a feeding device for an image forming apparatus which is characterized by the following.

[Effect]

According to the present invention, the recording medium is accommodated in the accommodating means arranged side by side in the feeding direction, and in each accommodating means, the leading end of the recording medium is brought into contact with the abutment means in the accommodating means and registered.

One endless conveying means sequentially moves over a plurality of storage means, and during feeding, a part of the endless conveying means, or if necessary, the whole, moves additionally to the conveying movement, and acts as a contact means. The endless conveying means is pressed by the pressing means, the endless conveying means contacts the recording medium, the recording medium is sucked by the suction force of the conveying means, and the recording medium is fed from the storage means and conveyed to the image forming section. Ru. When the pressing means is applied to each of the plurality of storage means at a predetermined timing, it is possible to continuously feed and convey a plurality of recording media one by one from the plurality of storage means. By selecting the timing, it is possible to provide almost no spacing between recording media.

When the conveyance means moves so as to come into contact with the recording medium, the contact means is moved in conjunction with the conveyance means, for example, by the conveyance means itself, to be pushed down and moved to a position where the recording medium can be fed.

When not feeding, the abutting means protrudes above the height of the recording medium, and when feeding, the abutting means is lowered to the feeding position.

The conveyance means feeds one recording medium by pushing down the abutment means for only one of the plurality of storage means;
It is possible to select IR to feed a plurality of recording media at the same time by simultaneously pushing down the abutment means of a plurality of storage means.

If it is possible to guide a recording medium on which an image has been formed on one side in the image forming section to an upstream storage means among a plurality of storage means, a new recording medium and a recording medium on which an image has been formed on one side are successively transferred to the image forming section. It is possible to perform double-sided continuous page copying of a document with continuous pages on both front and back sides, such as a book.

The recording medium with its leading edge aligned in the storage means can be sucked into the endless conveyance means and conveyed as it is to the image forming section, and the recording medium can be fed and conveyed in a registered state without the need for a special registration device. .

〔Example〕

The details of the present invention will be explained based on embodiments shown in the drawings.

In FIG. 1, a copying machine 1 as an example of an image forming apparatus according to the present invention includes a scanner device 2 for reading an image of a document;
The copying main body 3 has a built-in image forming section that forms an image based on information from the scanner device, and a paper bank device 4 that stores a large number of recording media for recording images, such as recording paper. The scanner device 2 is placed on the bank device 3, and the scanner device 2 is placed on the copying main body 3.

The copying main body 3 has an image forming section 5 and a paper feeding device 6 in FIG.

As shown in FIGS. 1 and 3, the scanner device 2 placed on the copying body 3 may be configured as an integral structure, as opposed to being formed as a separate structure separated from the copying body 3. You can also do it.

The scanner device 2 includes a contact glass 11 on which a document is placed, a document holder 12 that presses and fixes the document against the contact glass 11, and an optical device. The optical device includes a lamp 13 for illuminating and scanning an original on a contact glass 11, a first mirror 14 that scans and moves together with the lamp 13 and reflects light reflected from the original, and the first mirror 14.
A second mirror 15 and a third mirror 16 sequentially reflect the reflected light from the mirror I6, and the CCD 18 captures the reflected light from the third mirror I6.
It has a lens 17 that forms an image on the image. The second mirror 15 and the third mirror 16 are scanned at half the reading scanning speed of the lamp 13 .

The image forming section 5 built into the copying body 3 includes a writing optical device 7 . In FIGS. 2 and 4, the writing optical device 7 includes a semiconductor laser 21, a collimating lens 22 that converts the laser light emitted by the semiconductor laser 21 into a parallel light beam, and an aperture 23 that shapes the light beam into a light beam of a certain shape. and a cylinder lens 24 that makes the shaped beam from the aperture 23 enter the polygon mirror 25 in a compressed form in the sub-scanning direction. A polygon mirror 25 having an accurate polygonal shape is rotated in a constant direction at a constant speed by a polygon motor 26, and the incident laser beam is deflected by the rotation of the polygon mirror 25, and the deflected laser beam is passed through fθ lenses 27a, 27b, 27c.

The rotational speed of the polygon mirror 25 is determined by the speed, writing density, and number of surfaces of the image information holding means 31 of the image forming section 5, such as the photoreceptor 31.

The fθ lenses 27a, 27b, and 27c convert the scanning light with a constant angular velocity so that it scans the photoreceptor 31 at a constant speed, forms an image on the photoreceptor 31 so that it becomes the minimum light spot, and further tilts the surface of the photoreceptor 31. It has a correction function.

The light after passing through the fθ lens 27 (27a, 27b, 27c) is reflected by the mirror 28, and the light outside the image area is guided by the synchronization detection mirror 29 to the synchronization detection sensor 30, which outputs a cue signal in the main scanning direction. emit a signal. After a certain period of time after the synchronization signal is output from the synchronization detection sensor 30, the scanner device T
One line of image data is output based on the read image information from No. 2. The light as image data is reflected by the mirror 28 and forms an image on the photoreceptor 31 at the exposure position. By repeating this process, images are sequentially exposed onto the photoreceptor 31.

The photoreceptor 31 has a drum shape and has a photosensitive layer coated on its surface. Organic photoconductor (OPC), a-3t, is a photoconductor sensitive to the semiconductor laser wavelength of 780 nm.
, 5e-Te, etc. are known, but in this embodiment, an organic photoreceptor is used.

- When writing with a laser on g, apply light to the image area N/
P (negative/positive) process and P that shines light on the skin
There is a /P (positive-positive) process, and in this example, N
/P process.

The charger 32 uses a scorotron system having a grid on the photoreceptor side, and charges the surface of the photoreceptor 31 uniformly (-).
A laser beam is applied to the photosensitive area to lower the potential. As a result, -750 to -800■,
An electrostatic latent image of about -50V is formed in the image area. The electrostatic latent image is applied to the developing roller 33a by the developing device 33 at -500 to -
In a state where a bias voltage of 600 V is applied, the (-) charged toner is developed and visualized.

The image visualized by the developing device 33 is transferred from the back side of the conveyor belt 53 onto a recording medium, such as a recording paper such as transfer paper, which is synchronously fed to the photoreceptor 31 by the conveyor heald 53 of the paper feeder 6. During transfer charging 34, a (+) charge is applied and the image is transferred.

Toner remaining on the photoreceptor without being transferred to the recording paper is scraped off from the photoreceptor 31 by the cleaning device 35 and collected in a tank within the cleaning device 35. Furthermore, the potential pattern remaining on the photoreceptor 31 is erased by applying light from a static elimination lamp 36, and the reflection density on the surface of the photoreceptor is measured by a photosensor 37 provided at a position immediately after development is performed by the developer 33. The photosensor 37 consists of a combination of a light receiving element and a light emitting element. To measure the reflection density, write a certain pattern (for example, a pure black or halftone dot pattern) using the writing optical device 7 at a position corresponding to the photosensor reading position, and then develop the reflectance of the pattern area and the exposure of the area other than the pattern area. The density of the image is judged from the ratio of body reflectance, and if it is too light, a toner replenishment signal is issued.Also, the fact that the density does not increase even after replenishment can be used to detect an insufficient amount of toner.

The recording paper on which the image has been transferred is separated by curvature by a drive roller 54 wrapped around a conveyor belt 53, and sent to a fixing device 38. The fixing device 38 includes a heat roller 39 and a pressure roller 40.
The toner on the surface of the recording paper is fixed by a pair of fixing rollers. After fixing, the recording paper is guided to a paper discharge path 42 by a claw 41 and discharged by a paper discharge roller 43 during normal image formation, for example, copying.

The paper feed device 6 has a conveyance device 51 and a storage means, such as a paper feed tray or a paper feed cassette.

The conveying device 51 has an endless conveying means, for example, a conveying belt 53 that runs in endless circulation, and the conveying heald 53 has a driving roller 54, a first driven roller 55, a second driven roller 5, etc.
6 and adjustment roller 57 in sequence. The conveyor belt 53 is conveyed at a substantially constant speed by a drive roller 54. The conveyance heald 53 has a predetermined nip width between the drive roller 54 and the first driven roller 55, with the photoreceptor 31 coming into contact from the outside at an image forming position, for example, at a transfer position. A transfer charger 34 facing the photoreceptor 31 is arranged facing the inner surface of the conveyor belt 53.

Between the first driven roller 55 and the second driven roller 56,
A suitable number of pink-up rollers 58, for example two pick-up rollers 58, are arranged at suitable intervals inside the conveyor belt 53, and each pick-up roller 58 is formed to be able to move up and down. The spacing between the pickup rollers 58 can be changed as needed by moving one or more pickup rollers.

The first driven roller 55 and the adjustment roller 57 are formed to be movable in a substantially horizontal direction, and the adjustment roller 57 is formed so as to receive the tension of a spring 59 so as to always apply a predetermined tension to the conveyor belt 53.

As shown in FIGS. 5 and 6, the first driven roller 55 has shaft portions 55a at both ends rotatably supported by bearings 60, and the bearings 60 are slidable on a guide shaft 62 fixed to a side plate 61. It is formed as a supported slider. The shaft portion 55a may be fixed to a bearing 60, and the first driven roller 55 may be rotatably supported by the shaft portion 55a. The first driven roller 55 , that is, the bearing 60 is reciprocated along the guide shaft 62 by a moving device 63 . The moving device 63 performs additional movement of the conveying belt 53 in addition to the conveying movement by the drive roller 54, and is used as a feeding speed change device. The moving device 63 includes a drive shaft 6 rotatably supported by the side plate 61.
4, and a driven pulley 67 fixed to a driven shaft 66 rotatably supported by a side plate 61. The driving shaft 64 is rotationally driven by a moving motor 68. A drive heald 69 is wound around each drive pulley 65 and driven pulley 67, and the drive heald 69 is attached to the slider 60.
is fixed by a fixing plate 70. The drive heald 69 is moved forward and backward by the forward and reverse rotation of the moving motor 6B, and the slider 60
By moving along the guide shaft 62, the first driven roller 55 is moved substantially horizontally.

When the first driven roller 55 is at the home position, which is the right end position in the figure, it is detected by the home sensor 71.

The adjustment roller 57 is also moved in accordance with the movement of the first driven roller 55, so that the conveyor belt 53 can be maintained at a constant tension.

Therefore, the adjustment roller generally moves in the opposite direction to the first driven roller by a distance equal to the distance traveled by the first driven roller.

The moving speed V wa / s of the first driven roller 55 is the transport speed of the transport heald 53, that is, the circumferential speed vIII[Il
Assuming 1/2 of /S, that is, V = v / 2,
When the first driven roller 55 moves to the left in the figure, the conveyor belt 53 traveling in the direction of the arrow moves from the adjusting roller 57 to the second
In the section from the driven roller 56 to the first driven roller 55, that is, in the speed fluctuation region, the upper conveyor belt 53 is apparently shifted to a stopped state due to the action of the circumferential speed vmm/s and the moving speed IIIl/s. can be held. If the recording paper is sucked from the paper feed tray 52 during the stopped state in which the feeding speed indicated by the apparent speed above is zero, it becomes possible to feed the paper without using a registration device and without shifting the leading edge registration. In addition, the suction position is always the same, and no deviation occurs due to belt conveyance, and there is no need for a registration stop operation by a specially provided registration device for image positioning. This means that it is only necessary to control the paper feeding timing and the image formation start timing.

In the speed fluctuation region that is a part of the conveyor belt 53 due to the movement of the first driven roller 55, a speed change operation is performed in which the conveyor belt 53 appears to be in a top-stopped state and then returns to a predetermined speed. and passes through the transfer position to drive roller 5.
4 to the adjustment roller 57, that is, in the constant speed region, the conveyance heald 53 does not appear to undergo any apparent speed fluctuations and moves at a constant speed. Therefore, the peripheral speed of the conveying heald 53 remains unchanged while the recording paper is being transported to the transfer position and the fixing position by the fixing device 38. This causes an apparent upward speed change in a part of the conveyance heald 53, causing it to be in a stopped state, and even while paper feeding is being performed, another recording paper is conveyed by the same conveyance belt 53, and transfer, separation, and fixing are not affected in any way. This can be done without causing any problems. If the conveyance heald 53 is cleaned in a constant speed region in which it always runs at a constant speed, for example, by the belt cleaner 72 provided below the drive roller 54, cleaning defects will not occur.

When the conveyance belt 53 attracts the recording paper from the paper feed tray 52, the first driven roller 55 is moved to the right side in the figure and returned to the home position. At this time, the adjustment roller 57 is also moved.

When the first driven roller 55 returns to the home position,
The apparent speed in the speed variation region of the conveyor belt 55 increases to an upper speed, that is, the feeding speed increases to twice the speed in the constant speed region.

An upper presser roller 73 is disposed above the first driven roller 55 in FIG. 2, and a lower presser roller 74 is disposed on the lower right side of the first driven roller 55 in FIG. A guide plate 75 is provided between the presser rollers 74 and assists the conveyance of the recording paper conveyed by the conveyance heald 53 from the paper feed tray 52 so that the direction can be changed smoothly along the first driven roller 55. .

After the conveyor belt 53 is cleaned of dirt by a belt cleaner 72, a charging roller 76 disposed near the heald cleaner 72 forms a certain charge pattern on the conveyor belt 53. When a charge pattern is formed in a speed fluctuation area of the conveyance heald 53, such as when the charging roller 76 is disposed in circumferential contact with the second driven roller, the charge is applied in accordance with the change in the feeding speed of the conveyance belt 53. The transport heald 5 is controlled by changing the frequency of the charge, etc.
A certain charge pattern can be formed on 3.

The paper feed tray 52 is a front-loading recording paper stacking device, and the paper feed tray 52 is pulled out from the front of the copying machine 1, the recording paper 77 is set therein, and the paper feeding tray 52 is inserted into the copying machine l.
You can replenish recording paper by pushing it inside.

The paper feed tray 52 has a size series of recording paper (for example, A series,
B series, letter size, etc.). Although the A series will be explained here, the same applies to other series.

A center fence 78 is provided at the center of the paper feed tray 52, and a right fence 79 is provided on the right side, and the center fence 78 is collapsible as shown in FIG.

When setting A4 size recording paper, use the center fence 78.
Stand it up as shown in Figure 7, put it into the two tray chambers 80 and 81 formed on the left and right, respectively, and leave the space between 1 and 1 open.
The recording paper is placed inside the two tray chambers.

On the lower side of the paper feed tray 52, a rising tray 8 is provided in each of tray chambers 80 and 81 formed on the left and right sides of the central fence 78.
2 is provided.

When the central fence 78 is erected, the tray consisting of the tray chamber 80 and the rising tray 82 on the right side in FIG.
2 is called a second tray 52#.

As shown in FIGS. 7 to 9, the central fence 78 has an upper face guide 83 and a lower face guide 84, and corner guides 85 are provided at both ends of the upper face guide 83 and at both ends of the lower face guide 84, respectively. This prevents the recording paper 77 from shifting laterally.

The upper face guide 83 is vertically slidably inserted into the groove of the lower face guide 84, and the spring 86 is inserted into the groove of the lower face guide 84.
3 and the lower face guide 84. A groove is formed in the improved face guide 84 to improve the lower face guide 84.
can be inserted. Due to the action of the spring 86, the upper face guide 83 is maintained at a predetermined relative position with respect to the lower face guide 84 when no load is applied.

A notch 87 is provided at the center of the upper edge of the upper face guide 83.
is formed so that the operator's hand does not touch the recording paper 77 when setting it.

The lower face guide 84 is connected to the paper feed tray 52 by a support shaft 88.
It is rotatably supported by the frame. Lower face guide 84
It has an L-shaped finger portion 89 at its lower end. The lower face guide 8 is locked by the fingers 89 locking into the protruding locking portions 90 formed on the frame portion 52a of the paper feed tray 52.
4 is stopped in a substantially vertical position when it is rotated and stands up, and is prevented from rotating any further. A claw 89a is formed on the finger portion 89, and an upper hook portion 9 formed on the frame portion 52a.
1, the lower face guide 84 is prevented from rotating in the direction of falling and is held in the upright position. Claw 89a
pushes the upper face guide 83 sideways with such force that the hook 91 comes off due to elastic deformation, the center fence 78 rotates clockwise in the figure and falls over, causing the right tray chamber 80 to fall as shown in FIG. The space between the left tray chamber 81 and the left tray chamber 81 is opened.

When the center fence 78 falls, the upper face guide 83 and the lower face guide 84 are inserted into the recess 92 formed in the frame 52a of the paper feed tray 52 so as not to interfere with the recording paper placed on the rising tray 82. It is formed so that it is buried inside. The center fence 78 fell and the right tray room 8
0 and the left tray chamber 81 are in communication.
The claw 89a of the fallen lower face guide 84 is detected by pressing a switch 93 serving as a paper size sensor.

A paper end sensor 94 is provided on the upper surface of the rising tray 82 to detect the presence or absence of recording paper.

The central fence 78 can also be of a removable type instead of the retractable structure shown in the figure. Size detection at this time can be performed by providing a sensor that detects the presence or absence of the central fence 78.

The right fence 79 can also be formed by a lower face guide 84 and an upper face guide 83 in the same manner as shown in FIG. In this case, there is no need to overturn the right fence 79.

The recording paper 77 in the paper feed tray 52 is transferred to the transport heald 53.
One of the pink unrollers 58 that presses against the middle fence 78 is placed directly above the upper face guide 83 of the middle fence 78, and the other one is placed directly above the upper face guide 83 of the right fence 79. be done.

As shown in FIG. 10, one pink-up roller 58 disposed directly above each face guide 83 and one or more other pickup rollers 58 are rotatably supported by, for example, a carrier plate 95 as 1&li. . In the example shown, 2
The pick-up rollers 58 are mounted on the carrier plate 9 as 1&II.
Each set of pink up rollers 58 supported by 5 are supported at the same height.

The carrier plate 95 is always pulled up to a fixed position by a tension spring 96, and the conveyor belt 53 is pulled up by the upper face guide 83.
It is located away from the top surface of. The support plate 95 rests against a push-down device 97, for example a cam device, by the force of a spring 96. Pressing device 97 from the time of non-feeding shown in No. 1011iU
As a result of the operation, for example, the support plate 95 is pushed down by the rotation of the cam 99, and one of the pickup rollers 58 comes into contact with the upper face guide 83, as shown in FIG. The carrier plate 95 is pushed down until the conveyor belt 53 comes into contact with the recording paper 77 and is in a suction state. The push-down device 97, the carrier plate 95, and the pickup roller 58 act as pressing means for pressing the conveyance heald 53 against the recording medium, and as contact means for bringing a part of the conveyance belt 53 into contact with the recording medium by pressing.

Press down cover? As shown in FIG. 12, if the 1f97 is a cam device, it has a paper feed cam 99 fixed to the shaft 98 at a predetermined interval in the same posture. For example, as shown in FIG. 13, the paper feed cam 99 has an outer circumferential shape that forms a 144° range as a circular arc surface B with a radius R3, for example, a radius of 10 m, from the center of the shaft 98, and the remaining 2161 range. 108°
The center point A is a radius R2, for example, a point located at a position 6II11 from the center of the axis 98,
Connect arc surface B and center point A with a smooth curved surface.

The shaft 98 is connected via a spring clutch 100 to a drive shaft 102 to which a pulley 101 is fixed. The pulley 101 is driven by a motor via a timing heald 103 and a reduction gear (not shown). A stopper 104 is fixed to the shaft 98. The stopper 104 is the first
As shown in Figure 4, there are two stepped portions 105.10 on the outer periphery.
The locking bar 107 is formed of a substantially spiral-shaped claw having a diameter of 6, and the claw of the locking bar 107 engages with one step 105 to prevent the stopper 104 from rotating. The locking bar 107 is connected to the support shaft 10
8, and is always held in a locked position with respect to the stepped portion 105 or 106 by a spring 109. A plunger of a paper feed solenoid 110 is connected to the locking bar 107, and when the solenoid is energized, the locking bar 107 is rotated around the support shaft 108 against the force of the spring 109, and the step is removed. The lock on the portion 105 or 106 is released.

When the stopper 104 is rotated, the angle from the first step portion 105 to the second step portion 106 is set to 120°, and when the stopper 104 is locked at the first step portion 105, the locking bar 107
When the lock is released, the stopper 104 rotates 120 m, and the second step 106 locks with the locking bar 107, and the shaft 98
stop rotating. A locking bar 107 is attached to the first stepped portion 105.
In the locked state, point A of the paper feed cam 99 is in contact with the support plate 95 as shown in FIG. 10, and the support plate 95 is in the raised position.

The rotation of the pulley 101, which is driven by a motor (not shown) and transmits rotation of 12 Orpm, is caused by the spring clutch 1.
00 to the stopper 104, and when paper is fed, the paper feed solenoid 110 is energized and the stopper 104 is released, and the stopper 104, which is always receiving rotational moment, is
Since the lock was released, it started rotating for 0.25 seconds.
Afterwards, the paper feed solenoid 110 is deenergized and the locking bar 107
contacts the outer peripheral surface of the stopper 104 again. At this time, the stopper 104 has already made a half turn (180"), so
The second step portion 106 has passed, and the claw of the locking bar 107 engages with the first step 105 of the stopper 104 after one rotation, thereby stopping the stopper 104. From this operation ζ, the cam 99 rotates once in 0.5 seconds. The pickup roller 58 descends 40 degrees in 0.15 seconds together with the carrier plate 95, and stops for 0.2 seconds. At this time, as shown in FIG. , the arc surface B of the cam 99 is in contact with the support plate 95,
The support plate 95 is pushed down. After stopping for 0.2 seconds, it returns to the original position in 0.15 seconds. The pickup roller 58 and means for pressing down the pickup roller 58, such as a pressing device 97 and a support plate 95, are connected to the conveyor heald 5.
It acts as a suction operation means for activating the suction of No. 3.

The gap between the conveyor belt 53 and the recording paper 77 in the non-feeding state is approximately 4 m, and the gap with the upper face guide 83 is 2 I.
It is III11. Therefore, when the pickup roller 58 moves downward, the upper face guide 83 moves downward by 2M.
The upper face guide 83 is further pushed down and then lowered by 2Illffl. At this lowered position, the recording paper 77
The transport heald 53 is in contact with the.

At this time, the recording paper 77 is attracted to the conveyor belt 53 by an uneven electric field caused by a charge pattern formed in advance on the outer peripheral surface of the conveyor belt 53 by the charging roller 76 . The rising tray 82 is formed and controlled so that immediately after the pickup roller 58 moves downward, the rising tray 82 rises until the contact pressure between the recording paper 77 and the conveyance belt 53 reaches a predetermined value, and then stops. . As a result, recording paper 7 due to paper feeding
It is possible to correct the change in the lowering of the upper surface position of 7, and the paper feeding position can always be maintained at the same height.

The conveyance belt 53 has a feeding function of feeding the recording paper from the paper feed tray 52, a conveyance function of conveying it to the transfer position, and a transfer function of contributing to the transfer to the recording paper at the transfer position.

Since the conveyor belt 53 attracts and feeds the recording paper by the attraction force generated by an unequal electric field rather than by frictional force, there is no deviation of the recording paper, it has a registration function, there is no need to order paper powder during conveyance, and there is no need to remove static electricity after transfer. There is no.

The second stepped portion 106 of the stopper 104 is used when the paper feed tray 52 is replenished with recording paper, as will be described later.

As shown in FIGS. 2 and 15, waste trays 82 are individually arranged in a right tray chamber 80 and a left tray chamber 81, which are divided by the central fence 78 of the paper feed tray 52. As shown in FIGS. 15 and 16, the lifting device 123 that moves each lifting tray 82 up and down moves the lifting tray 82 up and down at four locations.
The wires 111 are fixed to the wires 111, respectively. The first wire 1lla among the four wires 111 is connected to the first guide pulley 1
12, it is turned by the second guide pulley 113 and its end is wrapped around the first drive pulley 114.

The first drive pulley 114 is fixed to a shaft 115 rotatably supported by the frame 52a of the paper feed tray 52. Same first
One end of the second wire ll1b is wound around the drive pulley 114, and the second wire 111b is turned and guided by the second guide pulley 113 midway.

The third wire 11 is fixed to the rising tray 82 on the opposite side from the first wire 111a and the second wire 1llb.
1C and the fourth wire 111d are each wound around a second drive pulley 116 whose ends are fixed to the shaft 115. Similarly to the first wire 111a, the third wire 111c is guided by the third guide pulley 117 and the fourth guide pulley 118, and is wound around the second drive pulley 116.
Similarly to the second wire 111b, the wire 11d is guided only by the fourth guide pulley 118 and wound around the second drive pulley 116.

One end of the shaft 115 is connected to the output side of the electromagnetic clutch 119, and an encoder 120 is fixed to the other end. The input side of the electromagnetic clutch 119 is connected to a tray motor 122 via a coupling 121. The camp ring 121 is the drive half 1 connected to the tray motor 122 side.
21a and the driven half 1 connected to the electromagnetic clutch 119 side
21b.

The lifting tray 82 and the lifting device 123 are formed to have the same structure for both the right tray chamber 80 and the left tray chamber 81, but in the illustrated example, they are formed approximately symmetrically with respect to the center fence 78. Rising tray 82 for the right tray room and left tray room 8
The No. 1 lifting tray 82 can be driven by a separate tray motor 122. If it is necessary to distinguish between the right tray chamber 80 and the left tray chamber 81, the right tray chamber 80 and the left tray chamber 80 are distinguished by adding an A after the symbol and the left tray chamber by adding a B after the symbol.

The electromagnetic clutch 119 transmits drive only when the torque on the output side is less than a predetermined value in one direction of rotation, and slips and does not transmit drive when the torque on the output side is more than a predetermined value. There is.

As a result, the rising tray 82 on which the recording paper 77 is placed rises due to the rotation of the tray motor 122, but when the top surface of the recording paper 77 comes into contact with the conveyance heald 53 and receives pressure, the electromagnetic clutch 119 is activated to slip. As a result, the rising tray 82 no longer rises, and the tray motor 122 stops after a predetermined period of time, so that the uppermost surface of the recording paper 77 is always maintained at a constant height.

When replenishing the recording paper 77, the paper feed tray 52 is pulled out from the front of the copying machine 1. At this time, the driving half 121a of the coupling attached to the copying machine 1 side and the side of the paper feed tray 52 are pulled out. The driven half 121b of the coupling attached to the tray 82 comes off, and the rising tray 82 lowers to the lowest position under its own weight. At the same time, the tray open/close sensor 124 (Fig. 2)
detects that the paper feed tray 52 has been pulled out.

After replenishing the recording paper 77, the paper feed tray 52 is loaded into the copy 4! !
1, the driving half 121a of the coupling attached to the copying machine side and the driven half 121b of the coupling attached to the paper feed tray side engage, and at the same time, the tray open/close sensor 124 opens the paper feed tray 52. Detects that the is set.

The paper feed solenoid 110 operates to move the locking bar 107 to the first position.
When the locking bar 107 is rotated clockwise in FIG. 4, the claw portion of the locking bar 107 is removed from the first step portion 105 of the stopper 104. The stopper 104, which has always been subjected to clockwise (rightward) rotational moment by the spring clutch 100, starts to rotate clockwise (rightward) because the regulating member is no longer present.

After 0.1 sec, the paper feed solenoid 110 is released and the locking bar 107 is again subjected to a counterclockwise rotational moment and comes into contact with the outer peripheral surface of the stopper 104. At this time,
Since the stopper 104 has only rotated 115 times (72°), it comes into contact with the outer circumferential surface between the first stepped portion 105 and the second stepped portion 106.

When the stopper 104 rotates exactly 120 degrees, the locking bar 10
The claw portion 7 engages with the second stepped portion 106 of the stopper 104 and stops.

At this time, the B side of the cam 99 is in contact with the carrier plate 95 and is stopped, and the conveyor belt 53 is at the paper feeding position.

Next, the tray motor 122 is activated to raise the raising tray 82 together with the recording paper 77. When the top surface of the recording paper 77 comes into contact with the conveyance heald 53 and receives pressure, the electromagnetic brake 11
It is stopped by the action of 9.

After a predetermined time, the tray motor 122 stops. Then, the paper feed solenoid 110 is activated to rotate the locking bar 107 clockwise. Then, the claw portion of the locking bar 107 is removed from the second stepped portion 106 of the stopper 104. The stopper 104, which has always been subjected to clockwise (rightward) rotational moment by the spring clutch 100, starts rotating clockwise because the regulating member is no longer present.

After 0.1 sec, the paper feed solenoid 110 is released and the locking bar 107 is again subjected to a counterclockwise rotational moment and comes into contact with the outer peripheral surface of the stopper 104. Stopper 1
04 rotates exactly 240°, the stop bar 107 again hits the first stepped portion 105 of the stopper 104 and stops. At this time, the conveyance heald 53 returns to its non-feeding position.

As described above, the first tray 52' and the second tray 52#
It is possible to replenish recording paper individually.

When the center fence 78 is folded down and A3 size recording paper is set in the paper feed tray 52 across the first tray 52' and the second tray 52#, the above-mentioned raising tray operation and cam operation are performed on the first tray 52' and the second tray 52'. , both are performed simultaneously on the second tray 52#.

This widens the contact head of the conveyor belt 53 during paper feeding, thereby stabilizing paper feeding and conveyance.

As mentioned above, during normal image formation, the recording paper fixed by the fixing device 38 in FIG.
1 to a paper ejection path 42, and ejected by a paper ejection roller 43. During double-sided copying, in which copies are made on both the front and back sides of the recording paper, the recording paper after fixing is reversed from front to back to the transfer position by the photoreceptor 31. It is necessary to feed paper to

For this reason, after three days of the fixing device, the claw 41 closes the sheet discharge path 42.
A return guide path 44 is provided as a switchable branch path for guiding the recording paper to the paper feed tray 52.

The return guide path 44 includes a reversing path 45 as a branch path, and at the branching position, it connects directly to the paper feed tray 52 and the reversing path 45.
The first switching claw 46a can switch between the passage and the passage.

The recording paper sent to the return guide path 44 is sent to the first switching claw 46a by the feed roller 47, and the recording paper guided to the reversing path 45 is nipped by the reversing roller 48 and sent to the rear end of the recording paper. When the reversing sensor 125 detects this, the reversing roller 48 rotates in the reverse direction and the sheet is reversely fed. The recording paper that is fed backwards is the second one.
The feed roller 4 of the return guide path 44 is controlled by the switching claw 46b.
9 and is discharged onto the paper feed tray 52.

Like A3 copy, the first tray 52' and the second tray 5
2# at the same time, the tray motor 122 is reversely rotated to lower the raising tray 82 by a certain amount after the paper feeding operation for front side copying.
After the recording paper 77 on which the front side has been copied is inserted into the paper feed tray 52, the ascending tray 82 is returned to its original position, the back side copy feeding operation is performed, and after the back side copy The recording paper 77 is discharged from the paper discharge path.

Like A4 copy, the first tray 52' and the second tray 5
2'', if the front copy is fed from the first tray 52', the tray motor 122
The ascending tray 82 of the second tray 52# is lowered by a certain amount by reversing the direction (lower by an encoder not shown!).
(to memorize the amount of movement), recording paper 7 with a copy on the front side
After the recording paper 77 is loaded onto the second tray 52, the ascending tray 82 is returned to its original position, and the feeding operation for backside copying is performed.After the backside copying, the recording paper 77 is ejected from the paper ejection path.

On the other hand, when feeding the front side copy from the second tray 52'', after the feeding operation of the front side copy, the raising tray 82 of the second tray 52# is lowered by a certain amount by reversing the tray motor 122 (using an encoder not shown). After the recording paper 77 with the front side copied is inserted into the second tray 52'+: return the ascending tray 82 to its original position and perform the feeding operation for the back side copy. After copying the back side, the recording paper 77 is discharged from the paper discharge path.

A recording paper upper limit sensor 126 is provided above the second tray 52#, and when in double-sided image forming mode, even if you try to lower the ascending tray 82, if it is full of recording paper, the operation panel will not allow double-sided copying. Display.

When you want to repeatedly form multiple images on the same side, such as composite copying instead of double-sided copying, the recording paper is moved to the reversing path 45.
The paper can be directly fed to the paper feed tray 52 by the first switching claw 46a without being guided by the paper feed tray 52.

In contrast to the automatic feeding of recording paper using the paper feed tray 52, there are cases where it is desired to manually feed the recording paper. For this purpose, a manual paper feeder 130 is provided.

The manual paper feed device includes a manual feed door (not shown) provided in the machine frame of the copying main body 3, guide plates 131 and 132 that guide the recording paper inserted through the manual feed door, and a manual paper feed roller 133.

When the manual feed door is opened, the manual feed mode is switched to, and the first driven roller 55 is returned to the manual feed home position.
When the manual feed sensor 134 detects that the recording paper is present in the manual paper feed device 130, a manual feed clutch (not shown) is activated, and the recording paper is conveyed onto the conveyance heald 53 by rotation of the manual paper feed roller 33.

The copying machine 1 has a minimum unit composed of a scanner device 2 and a copying body 3, and can function as a normal copying machine. In case of
For example, it is possible to use a paper bank device 4 that can accommodate a paper feed tray or a paper feed cassette, and includes a tray that can accommodate a large number of recording sheets. In this case, the copying body 3 is placed on the paper bank device 4 as shown in FIG. The casing of the copying body 3 has a paper feed path 136 that is open at the bottom and guides the recording paper fed from the paper bank device 4.
is provided. The paper feed path 136 is formed to be able to feed the recording paper to a home position, for example, a nip position between the first secondary roller 55 and the upper presser roller 74 located at the manual feed home position. A branch path 137 is provided in the paper feed path 136 so that the recording paper can be fed toward the first tray 52' of the paper feed tray 52, and a switching claw 138 is provided at the branch position to the branch path 137 to allow recording. It is possible to switch the paper feeding path. A paper bank paper feed sensor 139 is provided in the paper feed path 136 to detect that recording paper from the paper bank device 4 is fed. Paper banks are abbreviated as PB as necessary.

Paper bank device W4 has the 1st PB with a maximum capacity of 1250 sheets.
) A three-tier tray consisting of a second PB tray 201, a second PB tray 2o2, and a third PB tray 203, and a fourth PB tray 204 with a maximum loading capacity of 2000 sheets are equipped. Each PBI-
The paper feed for the trays 201 to 204 is carried out by one paper feeding conveyance device 2.
This is done by 05.

The paper feeding and conveying device 205 has an endless conveying means, for example, one endless belt 218, as shown in FIGS. 2 and 17. The endless belt 218 includes a fixed driving roller 211, a movable tension roller 212, a fixed turning roller 213, a driven roller 214, a pickup roller 215, a pair of belt speed change rollers 216, and an auxiliary turning roller. It is wrapped around the entire roller 217.

17 to 19, guide rods 207 are provided almost vertically on the front side plate 205 and back side plate 206 of the paper bank device 4, and the paper feed unit 22o is vertically slidably guided by the guide rods 207. Ru. The paper feeding unit 220 has a paper feeding unit front plate 222 and a paper feeding unit rear side plate 223 to which a bearing 221 that is slidably attached to the guide rod 207 is fixed. A driven roller 214, a pickup roller 215, and an auxiliary turning roller 217 are arranged so that both ends thereof are supported by the paper feeding unit front side plate 222 and the paper feeding unit rear side plate 223, respectively.

A pink amplifier auxiliary roller 219 is arranged to face the driven roller 214 so as to press the conveyor belt, that is, the PB endless heald 218, and the paper feeding unit front plate 222
and is rotatably supported by the rear side Fi 223 of the paper feed unit. When changing the conveyance direction, the pickup auxiliary roller 219
It serves to prevent the recording paper from peeling off from the B heald 218.

A shaft 21 that rotatably supports the pink up roller 215
Both ends of the paper feeding unit 5a are movably supported in an elongated hole 224 formed in the front side plate 222 of the paper feeding unit and an elongated hole 225 formed in the back side plate 223 of the paper feeding unit so as to be movable in a substantially horizontal direction. Further, both ends of the shaft 215a of the pickup roller 215 are fixed to the timing belt 226 by fixing fittings 227, respectively. The timing belt 226 is wound around a driving pulley 228 and a driven pulley 229, respectively. The drive pulley 228 is fixed to a common drive shaft 231 driven by a motor 230, and the drive shaft 231 is rotatably supported by the paper feeding unit front plate 222 and the paper feeding unit rear side plate 223. The driven pulleys 229 are rotatably supported by shafts individually attached to the paper feeding unit front plate 222 and the paper feeding unit rear side plate 223, respectively. The pickup roller 215 is reciprocated along the elongated holes 224 and 225 by driving the motor 230 in forward and reverse directions. Axis 21 of pick unroller 215
A home position feeler 232 and a bracket 234 for mounting an upper end detection sensor 233 for detecting the upper end of the recording paper are attached to 5a. When the home position feeler 232 activates the home position sensor 235 attached to the back side plate 223 of the paper feed unit, it is detected that the pickup roller 215 is at the home position. The upper end detection sensor 233 is the PB held 218
It is detected that the paper feeding surface has reached a height of 5ffiI11 from the top edge of the recording paper, and the paper feeding operation is performed from this position.

A lifting device 250 that moves the paper feeding unit 220 up and down is a motor 2 fixed to the back side plate 206 of the paper bank device.
51, and a drive shaft 25 rotatably supported by the back side plate 206 and the front side plate 205 and rotationally driven by the motor 251.
2, and two drive pulleys 2 fixed to the drive shaft 252.
53, a driven pulley 253 rotatably supported by the back side plate 206 and the front side plate 205, respectively, and two timing healds 254 wound around the drive pulley 252 and the driven pulley 253, respectively. The timing healds 254 are fixed to the front side plate 222 of the paper feed unit and the rear side plate 223 of the paper feed unit, respectively.
0, that is, the paper feeding unit front side plate 222 and the paper feeding unit rear side plate 223 are moved up and down.

Brackets 237 are fixed to the front shaft 236a, which is rotatably supported by the front side plate 222 of the paper feed unit, and the rear shaft 236b, which is rotatably supported by the rear side plate 223 of the paper feed unit, respectively. Both ends of the pair of belt speed change rollers 216 (216a, 216b) are supported. That is, the first belt speed change roller 216a and the second heald speed change roller 216b are supported by the bracket 237,
PB that runs between both belt speed change rollers 216a and 216b due to the rotation of the shaft 236 (236a, 236b)
The position relative to the belt 218 is changed. coax 236
(The front shaft 236a and the rear shaft 236b) are rotationally driven by a motor 238 to which the rear shaft 236b is connected. Rear shaft 23
A tweeter 239 is fixed to 6b, and the tweeter 239
is the sensor 240 fixed to the rear side plate 223 of the paper feed unit.
By operating the belt speed change roller 216, the home position of the belt speed change roller 216 is detected. By rotating the shaft 236, the belt speed change roller 216 rotates the PB belt 2 before the sheet feeding operation.
A portion of the PB heald 218 is wound around the first belt speed change roller 216a and the second belt speed change roller 216b, and the shaft 236 is rotated in the opposite direction during paper feeding operation to return the PB heald 218 that is being wound. The PB belt is returned to its original position and the feeding speed of the PB heald 218 is controlled.

The transport of the PB heald 218 is driven by a transmission device having a gear 242 driven by a motor 241 attached to the back side plate 206 and a gear 244 that meshes with the gear 242 and is fixed to the shaft 243 of the drive roller 211. This is done by rotationally driving 211.

In order to attract and convey the recording paper, the PB belt 218 is provided with a charging roller to form a charge density pattern. In the illustrated example, the auxiliary turning roller 217 is used as a charging roller, but it may be provided separately. An alternating current voltage, for example, ±2 KVP-P, 26 Hz, is applied to the charging roller 217 from the high-voltage power source 245 at a position before it contacts the recording paper, thereby creating a charge density of -
A striped charge density pattern is formed in which σ and +σ are alternately arranged at a period of, for example, 5 mm.

The paper feeding unit 220 feeds paper PB) rays 201 to 20.
4, and the driven roller 2 at that time is raised and moved according to the position of
Adjusting roller 212 moves in response to the movement of 14, so that the tension is always maintained constant. The adjustment roller 212 has an end supported by the front side plate 205 and an end supported by the back side plate 206, each connected to a spring 247 via a wire 246, and is pulled in a direction to apply tension to the PB health 218.

The 1st PB) Ray 20 is in the frame of the paper bank device 4.
Open/close sensor 26 for each of the first to fourth PB trays 204
1.262.263.264 are provided, and the opening and closing of each PB) ray 201 to 204 is detected.

For example, the 1st PB as a small tray with a maximum loading capacity of 250 sheets.
) Rays 201 to 3rd PB) Rays 203 include side fences 265 for determining the position of recording paper to be loaded as shown in FIG. 20 (explaining the first PB tray 201)
and an end fence 266. The side fence 265 and end fence 266 guide the recording paper in three directions. A fence may be provided at the front end in the paper feeding direction as long as it does not interfere with paper feeding.

The side fence 265 and the end fence 266 are movable in the direction of the arrow according to the size of the paper. P.B.
There is a handle 2 on the front wall of the tray 201 for easy loading and unloading.
67 may also be provided.

In Fig. 21, for example, the 4th PB) tray 204, which is a large tray with a maximum loading capacity of 2000 sheets, is the 1PB in Fig. 20.
) Similarly to the lay 201, a side fence 268 and an end fence 26'B: a handle 267 can be provided. 4th PB) Since the paper capacity is large in the Ray 204,
In order to prevent the paper from shifting, it is preferable that the side fence 268 is formed in an L shape and has a structure that guides the paper in the front, back, left and right directions. In this case, the cross-shaped side fence 268 is shaped so that it does not interfere with paper feeding.

The PB belt 53 in the copying body 3 attracts and conveys the recording paper with a charge density pattern formed by the charging roller 76.
In the paper bank device 4, the FB heald 218 forms a charge density pattern by the auxiliary turning roller 217 which acts as a charging roller, and attracts and conveys the recording paper. For this reason, the conveyor belt 53 and the PB heald 218 are formed as endless belts having a dielectric layer 53a capable of holding charges on the surface layer and a semiconductor layer 53b on the back surface. At least one of the rollers supporting the conveyor belt 53.218, for example roller 56.215, is grounded and arranged in contact with the back side of the heald.

As shown in FIG. 22, for example, an alternating electric field (AHz) is applied to the charging rollers 76 and 217 (only the millor rough 6 is shown in the figure) from the high voltage power supply 131 as opposed to the grounding roller 56. The conveyor belt 53 is the drive roller 5
4, the pickup roller moves in the direction of the arrow at a constant speed of U mm/s and contacts and attracts the recording paper.
It is on the downstream side of the contact position with 6. Therefore, an alternating current voltage is applied to the conveyor belt 53 from the high voltage power source 131 via the charging roller 76 before the recording paper comes into contact with the surface thereof. As a result, li of the conveyor belt 53 has a charge density of -
A striped charge density pattern is formed in which σ and +σ are alternately arranged at a period of U/Am. Transport heald 5
Charges of opposite polarity are induced in the semiconductor layer on the back surface of 3 due to the charge density formed on the surface of the transport heald.

When a charge density pattern as shown in FIG. 22 is formed, unequal charges 132 are formed near the surface of the conveyor belt 53 as shown in FIG. The force acting on a unit volume of can also be determined using Maxwell's stress tensor. The recording paper 77 is electrostatically attracted to the conveyor belt 53 by the force Fx in the direction perpendicular to the surface of the recording paper 77, that is, the surface of the sheet, and is held without shifting.
The paper is fed and conveyed.

When the direction perpendicular to the sheet surface is X, the transport direction is y, and the direction within the sheet surface perpendicular to the transport direction is z, the component force in each of the x, y, and z directions of the force acting on the unit volume of the dielectric is Fx ,Fy,F
Letting z be as follows.

Stress tensor E, 1) of Maxwe I 1), -T(F-p)ExD'Y EYI), ? ; Mon → (E-C)) EZp6 D2 Force acting on unit volume In contrast, the recording paper can be attracted using the method described above without applying any electric charge to the recording paper. For this reason, even if it is used in a paper feed conveyance device of an electrostatic recording device, it will not have any effect on the transfer process.

Although the example of the charge density pattern has a stripe shape, a checkerboard pattern may be used, and any appropriate pattern can be used.

As shown in Figure 24, when A3 size plain paper is fed to the conveyor belt and the contact length reaches 100 mm, a spring scale 133 is attached to the trailing edge of the paper, and the suction force is adjusted to the tensile strength. When measured as follows, the results shown in FIG. 25 were obtained. The adsorption area at this time was 300 ci''.

In Fig. 25, the amplitude of the AC voltage is constant, for example, 4KVP.
-P, and the results of measuring the adsorption force while changing the applied frequency are shown. From this, in the present invention, the period of the stripe shape is set to 2.
Sufficient adsorption force was obtained when the length was 0 m or less, particularly 10 m or less. Further, as shown in FIG. 26, the adsorption force was measured by changing the applied voltage while keeping the applied frequency constant, for example, 26H2, and from the results, good adsorption force was obtained at 2 KV, - or more. Furthermore, it was found from measuring the surface potential that no charge density pattern was formed on the belt at the applied voltage at which no adsorption force was generated. From this, in order to generate adsorption force, at least an applied voltage equal to or higher than the charging start voltage is required.

Further, the applied voltage is the same when a DC component is superimposed on an AC voltage, or when a non-uniform alternating voltage is applied from a power source that outputs a non-uniform alternating voltage.

Fig. 22 shows the belt configuration used in the paper feeding and conveying device of the present invention. Semiconductor layer (80 μm carbon dispersed in polyester #M resin, body resistance 1
The charging roller 76 is configured as an endless heald with a resistance of 0 Ωcm) and is rotatably supported by a drive roller and a plurality of support rollers.
An alternating voltage of 2KV, 24H2 is applied. Also,
The conveyor belt 53 is moved by a drive roller at a constant speed of 120 m/s in the direction of the arrow, and the recording paper feeding position is downstream from the contact position of the electrode of the charging roller 76 with respect to the moving direction of the conveyor belt 53. . Therefore, the conveyor belt 53
Before the recording paper is fed onto the surface of the recording paper, a charge density pattern is formed on the surface of the conveyor belt every 5 times. Here, the volume resistance of the back surface of the transport heald 53 is 10"Ω
The reason why it is set at 107 Ωcm is that in order to transfer data when the transfer means is installed on the back surface, the resistance must be 107 Ωcm or more. In addition, the above resistance was chosen because the adsorption force was greater when there was a difference in resistance with the surface layer.

However, the volume resistance of the back surface is actually 107 Ωcm ~ 101
If it is within the range of 1 Ωcm, there will be no functional problem.

In FIG. 23, the PB heald 218 used in the paper feeding and conveying device of the paper bank device 4 of the present invention is a two-layer type, with the surface layer being a dielectric film (PET 50 μm) and the lower layer being an endless belt made of vapor-deposited aluminum. It is rotatably supported by multiple support rows.

The volume resistance of this dielectric was set to 1016ΩCV. An alternating voltage of ±2 KV and 26 Hz is applied to the charging roller 217 from a high voltage power source B. Furthermore, the PB belt 218 is moved at a constant speed of 13oIIITI in the direction of the arrow by the drive roller.
The recording paper is moved at a rate of 1/S, and the paper feeding position of the recording paper is downstream of the contact position of the electrode of the charging roller 217 with respect to the moving direction of the PB belt. Therefore, before recording paper is fed onto the surface of the PB belt, a charge density pattern is formed on the surface of the PB belt at five spindle cycles.

The PB held 218 in the paper bank device 4 is the first
PB) Ray 201 to 4th PB) Recording paper is sucked and fed from the ray 204. For this purpose, the display device 250 is activated, and the paper feed unit 220 feeds the first PB tray 201 to the third PB tray.
Move up and down in front of the PIl Ray 203 to remove the first PB tray 2.
It is stopped at the sheet feeding home position of the 01 to 3rd PB trays 203. In FIG. 17, the fourth PB tray 204
Before the recording paper is fed onto the surface of the recording paper, a charge density pattern is formed on the surface of the PB heald at a period of 5 mm.

The PB held 218 in the paper bank device 4 is the first
PB) The recording paper is sucked and fed from the tray 201 to the fourth PB tray 204. For this purpose, the elevator W250 is activated, and the paper feeding unit 220 moves up and down in front of the first FBI-ray 201 to third PB tray 203, and is stopped at the paper feeding home position of the first to third PB trays 201 to 203. . In the 17th session, the 4th PB tray 20
4 is arranged shifted from the 1st PB) lay 201 to the 3rd PIl lay 203, and the paper feed unit 220 is directly connected to the 4th PB)
It can be moved onto the recording paper in the BL-ray, but
It can also be arranged in the same line as the first to third PB trays 201 to 203 and configured to move up and down in front of the fourth PBl-ray 204.

The paper feed home position is a certain distance above the top edge of the recording paper for all PB trays, for example, 5IIIff.
l upper position and the paper feed unit 7) 220 is selected.
B) When the tray moves to the paper feeding home position, the PB heald 218 is located 5 mm above the top edge of the recording paper.

When the PB heald 218 contacts the recording paper and feeds the recording paper by suction, the relative speed of a portion of the PB belt, that is, the contact portion with the recording paper, is changed to almost zero.

In order to change the feeding speed of a portion of the PB heald 218, that is, the relative speed with respect to the static recording paper, a feeding speed changing means;
For example, a pair of heald speed change rollers 216 (216a and 2
16b) is used.

In FIG. 27, belt speed change rollers 216a, 216
As an example, assume that each of b is a row having a diameter of 8+++ m, and the distance between the centers of the heald speed change rollers 216a and 216b is 12 m.
m, the belt speed change rollers 216a and 216b are rotated by the motor 238 around the approximate center point between the axes of the heald speed change rollers 216a and 216b, and the PB belt 2
18 is wound around the heald speed change rollers 216a and 216b, and the winding is released. In Figure 27, the center is 0.
The heald speed change rollers 216a, 216b are shown in solid lines around 1, and the angle θ is from the release position where the PB healds simply contact each other.
only to be rotated.

When the PB belt 218 itself is not being conveyed, the amount of movement l of the PB belt caused by the rotation of the belt speed change rollers 216a and 216b by θ (rad) is
1,=2 rθ+12(1-cosθ) where T is the radius of the winding of the heald speed change rollers 216a and 216b.

From the θ−ω relationship, the transition speed ■ can be expressed as a time derivative,
It becomes V-27ω+12ωsinωt. Here, ω is the rotational angular velocity.

When the PB heald 218 is moving at a constant speed of 130 mm/see and the paper feed unit 220 is lowered at 150 mm/sec, the contact area of the PB held 218 with the recording paper moves at 280 mm/sec. Therefore, in order to stop the PB belt 218 in the contact area with the recording paper, it is necessary to cancel this speed. For this purpose, by setting the transition speed (2) to 280 lungs/sec, the angular velocity ω, that is, the driving speed of the motor 238 that rotates the shaft 236 is obtained.

In other words, in the case of the first PB tray 201 to the third PB tray 203, the paper feeding unit 220 lands at 150 + nm/sec from the paper feeding home position shown in FIG. 28A to the position where it contacts the recording paper shown in FIG. 28B. At that time, the belt speed change roller 216 is connected to the belt speed change rollers 216a, 216b as shown in FIG.
The belt speed change rollers 216a and 216b are moved in the direction in which the belt is unwound from the wound state, for example, clockwise in the figure.
is rotated. The part of the PB held 218 that comes into contact with the recording paper is almost stationary, and the recording paper is moved to the PB belt 21.
It is electrostatically attracted by the charge density pattern of 8.

Thereafter, the paper feeding unit 220 is returned to the paper feeding home position shown in FIG. 28C.

4th PB) In the case of the ray 204, the recording paper 7 is
7 is fed by suction. In the case of the fourth PB tray 204, the leading edge of the recording paper 77 is sucked away from the contact area of the PB belt 218, so if the recording paper is conveyed in this state, the recording paper will gradually separate from the PB heald starting from the leading edge. It will end up being put away.

Therefore, the PB belt 218 descends from the paper feeding home position shown in FIG. 29(A) to the position shown in FIG. 29(B), contacts the recording paper 77 in a stationary state, and after suction,
As shown in FIG. 9C, while the paper feeding unit 220 ascends and returns to the paper feeding home position, the position where the leading edge of the recording paper contacts the driven roller 214 is already retracted by a certain amount.

For example, if the paper feed unit 220 is moved backward by 20 mm, the time it takes for the paper feed unit 220 to return to the paper feed home position is 5 (am) /150 (am/sec) -0
,033 (sec), and the linear velocity of the PB heald 218 in the opposite direction is 20 (+mn) 10.033 (sec)
-600 (mm/5ec). Since the PB heald 218 is conveyed at a constant speed of 130 mm/5ec,
When the paper feed unit 220 rises at 150 nm/sec, the heald speed change roller 216 is wound so that the PB heald 218 is returned at a rate of 600+13l30-150=580/see at the contact surface with the recording paper. do. Therefore, the above displacement speed V is set to 580 mm/5
ec to control the speed of the motor 238.

PB held 218 in the paper feeding process for the next recording paper
In preparation for the deceleration of the recording paper contact area, the belt speed change roller 216 is rotated in the range between adjacent recording papers being conveyed.

In contrast to the structure in which two rollers are rotated as in the example shown in FIGS. 27 to 29, as shown in FIGS. 30 and 31,
A structure including two fixed rollers 216' and one variable speed roller 216'' disposed between them can be used. FIG. 30 shows the first PB tray 210 to the third PB tray as shown in FIG. The example used in 203 is shown in the third
FIG. 1 shows an example of use in the fourth PB tray 204 as shown in FIG. 29. In FIG. 30, the variable speed roller 216'' moves to the paper feeding home position shown by the solid line, and while descending from that position to the position where it contacts the recording paper, it moves to the left in the figure and reaches the PB.
The speed of the recording paper contact area of the belt is decelerated or stopped, and the displacement roller 216'' is displaced to the leftmost position in the figure at the position where the belt returns to the paper feeding home position.

In FIG. 31, a process of retracting the recording paper contact area of the PB belt in the opposite direction is added to the example of FIG. 30.

The paper feed unit 22.0 moves 15 minutes from the paper feed home position.
The time it takes to descend 5DI at 0 + nm/sec and contact the recording paper is 5 (mm) / 150 (mm/5ec) = 0.0
33 seconds, during which time the PB Held 218 is 130 seconds.
The displacement roller 21G'' is displaced in the negative direction at 280 nun/sec in order to cancel the constant speed drive of mm/Sec and the landing displacement due to the descending speed of the paper feed unit 220 of 150 mm/sec.This displacement is 0.033 s.
Since ec is performed, the displacement amount is 280 (mm/5ec) X O,033 (sec)
= 9.3 (mm). For this purpose, the displacement roller 216# is 280 (mm/5ec)/2 = 1
It is sufficient to move uniformly to the left in the figure by 9.3 (mm) / 2 = 4.7 (+um) at a speed of 40 (mm/5ec).

In FIG. 31, since the leading edge of the recording paper is further transported backward to the position of the driven roller 214, the displacement roller 216# moves at a constant speed to the left in the diagram at a speed of 290 mn/sec and a displacement amount of 9.7 mm. .

The speed change operation is performed until the axial center of the displacement roller 216# reaches the point where the axial center of the displacement roller 216# moves to the left from the line connecting the axial centers of the fixed roller 216'.
In other words, a total displacement of 14.4 mm is performed by constant velocity control.

〔effect〕

According to the present invention, it becomes possible to feed and convey a recording medium in a registered state from any one or more of a plurality of storage means by one endless conveyance means, and the plurality of storage means can be arranged in a space-saving manner. Also, the operability and transferability have been greatly improved.

It was.

According to the present invention, it is possible to perform page continuous copying and page continuous copying by double-sided copying using a plurality of accommodating means without the need to provide a special intermediate accommodating means, thereby improving productivity.

According to the present invention, it has become possible to continuously feed a plurality of recording media at almost no intervals, improving productivity and making it possible to perform double-sided continuous image formation at high speed.

[Brief explanation of drawings]

FIG. 1 is an overall perspective view of an example of an image forming apparatus according to the present invention, FIG. 2 is a schematic front view, FIG. 3 is a schematic illustration of a scanner device, and FIG. 4 is a plan view of a writing optical device. FIG. 5 is a plan view of the conveyance means transmission, FIG. 6 is a perspective view of the conveyance means transmission, FIG. 7 is a front sectional view of a part of the storage means, and FIG.
9 is a perspective view of the partitioning means; FIG. 10 is a schematic front sectional view showing the storage means and the conveyance means contact device as the suction actuation means; 11 is a diagram corresponding to FIG. 10 showing the operating state of the conveying means contacting device, FIG. 12 is a perspective view showing the drive system of the conveying means contacting device, FIG. 13 is a front view of the cam, and FIG. 14 is a view corresponding to FIG. An explanatory diagram of the stopper of the drive system of the conveyance means contacting device [η, FIG. 15 is an overall perspective view of the storage means, FIG. 16 is a perspective view showing the drive system of the raising tray of the storage means, and FIG. 17 is a vapor bank device. FIG. 18 is a perspective view of the paper feeding unit, FIG. 19 is a plan view of the paper feeding unit, FIG. 20 is a perspective view of an example of the storage means, and FIG. 21 is a perspective view of another example of the storage means. 22 is a perspective view illustrating the formation of an alternating electric field on the conveyance means, FIG. 23 is a front view illustrating the formation of an alternating electric field, FIG. FIG. 26 is a diagram showing the relationship between the pinch of the alternating electric field and the tensile force indicating the attraction force, FIG. 26 is a diagram showing the relationship between the applied voltage of the alternating electric field and the tensile force, and FIG. 27 is an explanation of another example of the conveying means transmission device. 28 is an operation diagram showing the operating states of the conveying means transmission according to FIG. 27 as A, B, and C sequentially, and FIG. 28, FIG. 30 is an explanatory diagram of another example of the conveying means transmission, and FIG. 31 is a diagram corresponding to FIG. 30 of an example in which the speed change steps are modified from FIG. 30. 31... Image information holding means 52, 52', 52'... Accommodating means 53...
Endless conveyance means 55...Followed roller 5 days...Pickup roller (contact means) 63...
Additional moving device 76... Charging means 77... Recording paper 78...
・Central fence C contact means) 79... Right fence (contact means) 83... Upper face guide (contact means) 84... Lower face guide (contact means) Fig. 3 Fig. 4 Fig. 4 5 Fig. 20 Fig. 24 Fig. 25

Claims (5)

[Claims] (1) A storage means for storing a recording medium on which an image is recorded;
In the feeding device of an image forming apparatus, the feeding device includes an endless conveyance means for adsorbing and conveying the recording medium from the storage means to an image forming position by an image information holding means, wherein a plurality of the storage means are arranged in a moving direction of the endless conveyance means. 1. A feeding device for an image forming apparatus, characterized in that a vertically movable abutting device is provided at a position where a leading edge of the recording medium of each accommodating device abuts. (2) At least a portion of the endless conveyance means moves to a position where it contacts the recording medium during feeding, and the contact means is lowered to a predetermined position in conjunction with the endless conveyance means. A feeding device for an image forming apparatus according to claim 1, characterized in that: (3) The recording medium after the image formation by the image information holding means is formed so as to be guided to an upstream storage means in the feeding direction among the plurality of storage means. A feeding device for an image forming apparatus according to . (4) At the time of double-sided image formation, a recording medium on which a single-sided image has been formed is stored upside down in the upstream storage means, and the recording medium is simultaneously transferred from the storage means and the downstream storage means adjacent thereto to the endless conveyance means. 4. The feeding device for an image forming apparatus according to claim 3, wherein the feeding device is fed by a feeding device. (5) The image according to any one of claims 1 to 4, wherein the adjacent storage means are arranged very close to each other or are integrally formed, and the recording medium is continuously fed with almost no intervals. Feeding device for forming equipment.