JPH0441341A - Paper feeding device - Google Patents

Abstract

PURPOSE:To place plural sheets and feed them sheet by sheet by providing a solenoid for engaging/disengaging a clutch means, a sector gear rotated under control reacting to the action of the solenoid and clutch means, and a connecting member for oscillating a push-up member reacting to the rotation of the sector gear. CONSTITUTION:A carrier roller shaft drives/rotates a sector gear 20 through gear transmission, so that a connecting member 19 such as a coil spring with one end thereof hooked to the sector gear 20 is expanded, and a push-up member (sheet lifting plate) 13 hooked to the other end of the spring is oscillated to lift a sheet P. When the sector gear 20 is further rotated by the specified quantity, its ungeared part turns up, but the sector gear 20 continues its rotation by the energizing force of the expanded spring until a stopper 20D integrally provided at the sector gear 20 is brought into contact with a change-over lever 28. With this sheet lifting and the rotation of a carrier roller, one sheet in the uppermost layer of a bunch of sheets P placed on a movable baseplate is delivered and conveyed to a resist roller provided on the conveyance downstream side.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a paper feeding device for sheet paper in an image recording device such as a copying machine, a facsimile machine, a printer, etc. The present invention relates to an improvement in a paper feeding device that feeds paper sheets one by one from a paper feeding cassette, manual paper tray, or the like.

[Conventional technology]

Traditionally, in recording devices such as copying machines, sheets of paper (recording paper, originals, etc.) stored in a stack in a paper tray, paper feed cassette, paper stacker, etc. are taken out one by one from the top, and images are printed. A paper feeding device is provided to feed the paper to the recording section, etc.

For the upper paper feed cassette, a corner separation method using separation claws and a friction separation method using rollers, belts, etc. are generally used.

The paper feeding device disclosed in Japanese Patent Application Laid-open No. 55-135034 is a paper feeding device that includes a corner separator (separation claw), a bottom plate push-up member that swings by an operating force, a movable bottom plate, and a paper feeding roller. It is a device.

A paper feeding device disclosed in Japanese Patent Application Laid-open No. 56-46255 is a paper feeding device that includes a corner separator, a coil spring, and a paper feeding roller.

In addition, a friction separation type paper feeding device was developed in Japanese Patent Application Laid-Open No. 63-127.
No. 935, Japanese Unexamined Patent Publication No. 1-123772, Japanese Unexamined Utility Model No. 1-96
441 and Utility Model Application Publication No. 1-121036.

In this method, since there is no separating claw or coil spring in the paper feed cassette, loading and replacing recording paper is easier than in the corner separator method.

In the friction separation type paper feeding device, near the leading end in the feeding direction of the paper stack housed in the paper feeding cassette, there is a feed roller of the paper feeding device that presses against the paper stack, and a roller to prevent double feeding. It is equipped with a feed roller and a reverse roller. When the paper feed cassette is installed in the paper feed section of the recording device, the pressing force and spring biasing force of the cassette are applied, or the motor starts to drive, and this driving force moves the swing shaft to which the push-up plate is fixed. The movable bottom plate is configured to be rotated to swing the push-up plate and raise and lower the movable bottom plate.

[Problem to be solved by the invention]

If the movable bottom plate is raised by being biased by a coil spring, the biasing force of the spring changes depending on the thickness of the stack of sheets, and there is a drawback that a uniform pressing force cannot be obtained. In addition, the spring biasing force described above is the weight of the paper stack loaded on the movable bottom plate, that is, the size of the paper (A6 size to A3 size).
, number of sheets of paper stack (1 to 500 sheets), paper weight (40 to 500 sheets),
70 kg), it is difficult to support these various types of paper using the spring biasing force and press it uniformly against the feed roller. In particular, when storing a large amount of paper in the paper feed cassette, the spring biasing force cannot cope with the problem.

To solve this problem, a method of raising the movable bottom plate using the driving force of a motor has been put into practice. On/Off drive
Since the off-state is operated in conjunction with each other via multiple solenoids and multiple clutches from the drive source motor through power transmission means such as gear trains, intermittent drive control is complex and the structure is complicated, making it difficult to manufacture. The cost will be high.

In addition, according to the paper feeding device of a copying machine disclosed in Japanese Patent Application Laid-Open No. 48-104545, a switching device consisting of a cam plate or the like that is operated by a plurality of electromagnetic magnets from a single drive source via a gear train. A mechanism switches the copy paper feed. However, such a switching mechanism consisting of magnets, cam plates, links, gears, etc. is not only extremely complicated, but also has problems in the stability and reliability of its operation.

On the other hand, sheet-like recording paper is usually used by storing a large number of sheets of frequently used sizes and paper quality in a special paper feed cassette made to suit the paper feed cassette and loading it into the recording device. The sheets are automatically pulled out one by one from the cassette by a paper feeding means such as a paper roller and fed into the machine.

Although this automatic paper feeding method is suitable when you want to obtain a large number of copies of the same size and paper quality, if you want to change the size or paper quality of the recording paper, even if the amount is There are many inconveniences, such as having to replace each cassette even if the paper is large, and not being able to use non-standard sized recording paper that does not fit in the cassette. any size,
There is a copying machine equipped with a manual paper feeder that can feed paper-quality recording paper one sheet at a time.

This manual paper feeder is equipped with a recording paper loading plate that is pivotably attached to the side of the image recording device so that it can be raised and lowered, and in the case of automatic paper feeding using the paper feeding power center, it can be raised up and placed on the side of the recording device. However, when it is rotated and placed in a position where manual paper feeding is possible, the paper feeding function from the paper feed cassette is stopped and the manual paper inserted from the recording paper placement plate is stored. The recording paper is introduced into the conveyance section of the recording device and subjected to image transfer, which has the advantage of being able to quickly record non-standard recording paper or small amounts of recording paper at any time without having to attach or remove the paper feed cassette. There is.

However, when recording a large amount of images using recording paper of different quality or non-standard recording paper, it is extremely difficult to feed the recording paper sheet by sheet using the manual paper feeder described above. In recent years, manual paper feeding devices (multi-paper toilets) have come into use, which are inefficient and which place a certain amount of recording paper all at once and automatically feed the paper from the top.

Such a manual paper feeding device, for example, Utility Model Application No. 63-139
Publication No. 34 requires a mechanism that repeatedly presses and separates the recording paper from a feeding means such as a feeding roller each time it is fed, and it is also necessary to synchronize the pressing and feeding. This has the disadvantage that the structure is complicated and the device is expensive.

[Means to solve the problem]

This invention eliminates the drawbacks of the conventional paper feeding device as described above, has a simple structure and reliable operation, prevents damage to the device, eliminates the need for operational precautions, and achieves normal paper feeding. The purpose is to provide a paper feeding device that can.

A paper feeding device of the present invention that achieves the above object swings a paper stacker stacked and stored with a plurality of sheets to a predetermined position while supporting a part of the sheets stored in the paper stacker. a clutch means for controlling drive rotation of the conveyance member, comprising a push-up member for lifting up the sheets, and a rotatable conveyance member for conveying the sheets in the paper feed stacker one by one to a processing section; , a solenoid that engages and disengages, a sector gear that controls rotation in response to the operation of the solenoid and the clutch means, and a connecting member that swings the push-up member in response to rotation of the sector gear. It is characterized by:

Further, the paper feeding device of the present invention is characterized in that engagement and disengagement of the clutch means and rotation stop of the sector gear are performed by a swingable switching lever connected to the solenoid.

[Effect]

(1) When the paper feed tray of the manual paper feed section of the main body of the recording apparatus is set and a stack of paper is placed, the switch is turned on and the solenoid is energized. When the plunger of the solenoid is attracted, the switching lever connected to the plunger releases the clutch, and the driving force from the drive source passes through the connected gears to drive and rotate the conveying roller shaft, and the sheet is conveyed. Rotate the feed roller and pickup roller.

At the same time, the conveyance roller shaft drives and rotates the sector gear through gear transmission, and a connecting member such as a coil spring that is hooked at one end to the sector gear is stretched, and a push-up member that is hooked to the other end of the spring. (Paper liquid lifting plate) to lift the paper.

When the sector gear continues to rotate a predetermined amount, it becomes a part without a gear. However, due to the biasing force of the stretched spring, the sector gear continues to rotate until a stopper provided integrally with the sector gear comes into contact with the switching lever.

(2) By lifting the paper and rotating the conveyance roller,
One of the top sheets of the stack of sheets on the movable bottom plate is sent out and conveyed to registration rollers provided on the downstream side of the conveyance.

(3) After a predetermined period of time has elapsed, the solenoid is turned off, the plunger protrudes, the clutch is engaged, and the rotation of the conveyance roller is stopped.

At the same time, the switching lever is detached from the gear of the sector gear and falls under its own weight to the paper lifting plate, the sector gear is also pulled by the coil spring, and the gear of the sector gear hits the gear of the stopped conveyance roller shaft. They are rotated until they make contact, and this contact stops the rotation.

When the registration roller is driven while the paper lifting plate is lowered and the transport roller is stopped rotating, the transported paper is
A sheet is conveyed by registration rollers and sent to a processing section.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The paper feeding device of the present invention will be explained below using an embodiment of the paper feeding device shown in the accompanying drawings.

FIG. 1 is a sectional view of a main part of an image recording apparatus in which a paper feed cassette and a manual paper feed tray are in a state where paper can be fed. The paper feed device according to the present invention can be applied to paper feed stackers such as the above-mentioned paper feed cassette and manual paper feed tray, as well as intermediate stackers that enable double-sided recording and paper feed trays of automatic document feeders. , a manual paper feeder will be described below as an example.

Paper tray (paper stacker) of manual paper feeder lO
11 and the paper stack P stacked on the guide plate 12 is moved by a paper lifting plate (pushing member) 1 which is activated by a paper feed signal.
3 and pickup roller 14, and is then fed to the nip position between the feed roller 15 and reverse roller 16 and conveyed. When the leading edge of the paper P is detected by the sensor 2 immediately before the registration roller 1, the CPU be stopped under the control of At this point, a toner image is formed on the image forming member (photosensitive drum) 3 by charging by a charger 4, exposing the image of the document by a scanning optical system, and developing by a developing device 5.

Next, the registration roller l is rotated in accordance with the above-mentioned image forming timing, and the paper P is conveyed to the transfer area by the transfer device 6 in accordance with the circumferential speed of the image forming body 3, and the toner formed on the image forming body 3 is transferred. The image is transferred onto paper P.

The paper P on which the toner image has been transferred is separated from the circumferential surface of the image forming body 3 by a separator 7, transported by a conveyor belt 8, passed through a fixing device (not shown) and a paper ejection roller, and is placed on a paper ejection tray. Ru.

Note that 9 is a paper feed cassette that is removably provided at the bottom of the main body of the image forming apparatus. One sheet of paper is sent out by the conveyance members 9A, 9B from the bundle of many sheets housed in the paper feed cassette 9, passes through the intermediate conveyance roller 9C, and then
The image is sent to the nip position between the field roller 15 and the reverse roller 16, and is further conveyed to the surface of the image forming member 3 via the registration roller 1 in the same manner as described above.

FIG. 2 is a sectional view showing the state of the manual paper feeder 10 before paper feeding starts, FIG. 3 is a front view of the main part of the drive system of the paper feeder IO in this state, and FIG. 1 is a plan view of the device 10. FIG.

The paper tray 11 is pivoted to a pivot shaft provided on the side wall of the image recording apparatus main body 100, and is configured to be able to rise and fall with respect to the main body 100.

The guide plate 12 engages with the hook portion of the sheet stacking tray 11, is movable in conjunction with the raising and lowering operation of the tray 11, and has an abutting surface 12 that aligns the leading edge of the stack of sheets P to be stacked.
A, and a guide surface 1.2B that guides the sheet to the nip position between the feed roller 15 and reverse roller 16.

A rectangular notch hole 12c is bored in the guide plate 12, and a paper lifting plate 13 protrudes and retracts from this notch hole 12C to lift the paper placed on the guide plate 12 and the paper tray 11. P is pushed upward and comes into pressure contact with the pickup roller 14.

The base of the paper lifting plate 13 is screwed to approximately the center of a swing support shaft 17 mounted on a side surface 101 of the recording apparatus main body 100.

A swinging member 18 is fixed to one shaft end of the swinging support shaft 17, and one end of a coil spring 19 is suspended in a small hole 18A near the tip of the swinging member 18.

The other end of the coil spring 19 is suspended on a protrusion 20^ of the sector gear 20. The sector gear 20 is attached to the side wall 1
It fits into a fixed shaft 21 implanted in 01 and is rotatable. A gear portion 20B notch portion 20C is formed on the circumferential surface of the sector gear 20.

The gear portion 20B meshes with a gear 23 fixed near the shaft end of the conveyance roller shaft 22 of the feed roller 15.

An oven type spring clutch (clutch means) 24 is provided at the most axial end of the conveyance roller shaft 22, and connects and disconnects power transmission with a gear 25 meshing with a drive input gear 26 connected to a drive source.

Ratchet teeth 27 are provided on the outermost periphery of the spring clutch 24, and engage and disengage one claw portion 28A of the switching lever 28. The switching lever 28 is swingable about a fixed shaft 29, and a claw portion 28B formed at the other end engages and disengages the gear portion 20B of the sector gear 20.
It can come into contact with a stopper portion 20D protruding from the surface of the sector gear 20.

A groove portion 28 is provided near one claw portion 28A of the switching lever 28.
C is formed. The pin 31A implanted in the plunger 31 of the solenoid 30 fixed to the side wall 101 is slidably engaged with the groove 28C.

Next, the operation of the manual paper feeder having the above configuration will be explained.

■First, in Figures 2 and 3, the paper tray 11
When you move from the upright, retracted state to the state where manual paper feeding is possible,
The paper tray 11 is connected to the pivot shaft 10 of the recording apparatus main body 100.
2 as the center of rotation, it rotates clockwise in the figure, and comes into contact with a stopper (not shown) to come to a stopped state.

■In this state, the paper stack P is placed between the paper loading tray 11 and the guide plate 12. When the paper is placed on each upper surface of the paper lifting plate 13 and the leading edge of the paper is brought into contact with the abutting surface 12^, the light shielding plate 32 that opens and closes the optical sensor swings, causing a paper feeding start signal to be issued.

(2) In response to the paper feed start signal, voltage is applied to the solenoid 30 and the plunger 31 is attracted. The plunger 3
1, the switching lever 2 engages with the bin 31A.
8, the groove 28C moves, and the switching lever 28 moves to the fixed shaft 2.
It swings counterclockwise around 9.

As a result, the pawl portion 28^ of the switching lever 28 is disengaged from the ratchet teeth 27, and the spring clutch 24, which is integral with the ratchet teeth 27, is unlocked and becomes rotatable.

(2) A voltage is applied to a motor (not shown) as a drive source, and the drive input gear 26 starts rotating through a drive transmission system consisting of a gear train and the like. The gear 26 transmits driving force by releasing the spring clutch 24, rotates the conveying roller shaft 22, rotates the feed roller 15, and further rotates the pick-up roller 14 via the intermediate gear 33. let

(2) At the same time, the gear 23 fixed to the transport roller shaft 22 rotates and meshes with the gear portion 20B of the sector gear 20 to transmit rotation, thereby rotating the sector gear 20 counterclockwise.

(2) As the sector gear 20 rotates, the projection 20A also moves together and gradually moves away from the swinging member 18. The coil spring 19 stretched between the protrusion 20A and the small hole 18A of the swinging member 18 is gradually tightened. The spring biasing force causes the swinging member 18 to swing clockwise, and the swinging support shaft 17 that is integrated with the swinging member 18 also swings to lift the paper lifting plate 13 clockwise.
A stack of sheets P stacked on the sheet lifting plate 13 is pressed against the surface of the pickup roller 14.

■The rotating pickup roller 14 sends out the upper layer of the paper bundle P that has been pressed into contact with the paper, and the feed roller 16
One sheet of paper P is fed out and conveyed to the registration rollers 1.

- As the sector gear 20 rotates, the stopper part 20D that is integral with the sector gear 20 also moves (However, when its negative end surface comes into contact with the claw part 28B of the switching lever 28, the rotation of the sector gear 20 stops. At this time, the notch 20C of the sector gear 20 faces the gear 23, and the driving rotational force is no longer transmitted. FIGS. 5 and 6 show this final state.

■After a predetermined period of time, the solenoid 30 is turned off, the plunger 31 protrudes, and the spring clutch 24 is locked;
The rotation of the conveyance roller shaft 22 is stopped.

At the same time, the switching lever 28 moves the gear portion 2 of the sector gear 20.
0B, the paper lifting plate 13 falls under its own weight, and the sector gear 20 is also pulled by the coil spring 19. At N, the sector gear 20 hits the gear 23 of the conveyance roller shaft 22, whose gear part 20B is stopped. They are rotated until they make contact, and this contact stops the rotation.

[Phase] The above-mentioned raising of the paper push-up plate 13 and rotation of the conveyance rollers (pickup roller 14 and foot roller 15) are repeated every time one paper is sent out.

〔Effect of the invention〕

As described above, according to the present invention, the pressing operation of one paper push-up plate and the paper feeding operation by rotation of the conveyance roller are performed using one solenoid, one spring clutch, and a sector gear. As a result, complicated mechanisms and synchronization can be omitted, making it possible to provide a manual paper feeding device that can load multiple sheets of paper and feed them one by one, which provides a simple and reliable paper feeding effect. .

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of an image recording apparatus showing a state in which a manual paper feeding device according to the present invention is set to enable manual paper feeding;
FIG. 2 is a sectional view showing the state of the manual paper feeder before paper feeding starts, FIG. 3 is a front view of the main parts of the drive system of each paper device feeding in this state, and FIG. 4 is a cross-sectional view of the paper feeder. FIG. 5 is a plan view, FIG. 5 is a sectional view of the paper feeding device after feeding one sheet, and FIG. 6 is a front view thereof. lO...Manual paper feeder 11...Paper loading tray (paper feed stacker) 12...
Guide plate 13...paper lifting plate (pushing member) 14...pickup roller (conveyance member) 15...feed roller (conveyance member) 16...reverse roller 17...swing shaft 18... ... Swinging member 19 ... Coil spring 20 ... Sector - Gear 20B ... Gear part 20C ... Notch part 20D
... Stopper part 22 ... Conveyance roller shaft 23 ...
Gear 24... Spring clutch (clutch means) 25... Gear 26... Drive input gear 27... Ratchet teeth 28A, 29B... Claw portion 31... Plunger 101... Side wall P...・Paper, paper stack 28...Switching lever 30...Solenoid 100...Recording device main body

Claims (2)

[Claims] (1) A paper feed stacker that stacks and stores a plurality of sheets, a push-up member that supports a portion of the sheets stored in the paper feed stacker and lifts it up to a predetermined position; a rotatable conveyance member that conveys sheets in a paper stacker one by one to a processing section; a clutch means for controlling drive rotation of the conveyance member; a solenoid for engaging and disengaging the clutch means; and a sector gear whose rotation is controlled in response to the operation of a clutch means; and a connection member which swings the push-up member in response to the rotation of the sector gear. (2) The paper feeding device according to claim 1, wherein engagement and disengagement of the clutch means and rotation stop of the sector gear are performed by a swingable switching lever connected to the solenoid.