JPH0472242A - Paper feeding device - Google Patents

Abstract

PURPOSE:To realize a space saving and a low cost by providing a feed roller and a reverse roller at the lower side of the upper surface of the upper step paper laminating member, and at the upper side of the lower surface of the lower step paper laminating member, and a remaining paper returning member on the axis same as the feed roller. CONSTITUTION:Calling rollers 6 and 7 are provided to paper laminating members respectively, and a pair of separating rollers 11 and 12 are used to the upper and the lower steps of paper laminating members concurrently. When the papers are conveyed by the feed roller 11, the projection 70a of a return lever 70 is abutted to a rib 8a, and a one-way clutch and a shaft are in a racing condition. When the paper feeding is finished, an electromagnetic clutch on the axis same as the feed roller 11 is turned off, and the feed roller 11 is rotated clockwise following the counterclockwise rotation of the reverse roller 12. As a result, the projection 70a is abutted to a guide plate 71, and the one-way clutch and the shaft are rotated until the clutch is cocked. Since the tips of papers remaining at a nip are pushed back by a projection 70b, and the tip of an elastic sheet 72 pushes them back further, the conveying route of a tray after converting receives no disturbance. The return lever 70 returns to the original position in a resupply of the papers by the one-way clutch.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a paper feeding device applied to an image forming apparatus such as a copying machine, a printer, or a facsimile machine, and particularly relates to a paper feeding device that is arranged in multiple stages in parallel in the vertical direction. The present invention relates to a paper feeding device having a paper stacking section (cassette or tray).

[Conventional technology]

2. Description of the Related Art Copying machines are widely known in which transfer sheets of different sizes and types, or of the same size but for horizontal feeding or vertical feeding, are housed in dedicated cassettes, and are used by selecting the appropriate cassette depending on the application.

When such a large number of dedicated cassettes are installed within the main body of a copying machine or in a large paper feed unit separated from the main body, it is common to arrange them vertically in parallel.

In the above-mentioned paper feeding device, in addition to originally arranging a large number of cassettes, there is also a call roller dedicated to each cassette and a pair of separation rollers that separate the transfer sheets one by one, which necessitates an increase in the size of the device. was.

For this reason, for example, Japanese Utility Model Application Publication No. 63-200540 proposes a technique of arranging cassettes symmetrically around a paper feed roller to reduce the number of paper feed rollers.

[Problem to be solved by the invention]

However, in the above-mentioned conventional technology, the upper cassette feeds the stacked transfer paper from the lowest paper, so-called sketch paper, and the load (paper feed pressure) applied to the paper feed roller changes depending on the amount of transfer paper loaded. However, the disadvantage was that stable paper feeding performance could not be obtained.

In order to save space and reduce costs while maintaining stable paper feeding performance, it is conceivable to use one pair of separation rollers for the two adjacent upper and lower paper stacking sections. In a configuration in which the mechanism is also used, problems will arise if residual paper remains in the separation section nip. In other words, if the transfer paper sent from the upper paper stack remains in the nip after being separated, for example, if the paper is then fed from the lower paper stack, the lower transfer paper will fall into the nip of the pair of separation rollers together with the remaining paper from the upper paper stack. Because of this, there is a problem in that the lower paper is separated by the friction separation method that separates the lower paper and returns it to its original state, and the remaining paper on the upper shelf is mistakenly fed.

The present invention has been made based on this background, and an object of the present invention is to provide a paper feeding device that can save space and reduce costs of the device, as well as obtain stable paper feeding performance and separation performance. purpose.

[Means to solve the problem]

The above purpose is to provide paper stacking sections arranged in at least two or more stages in the vertical direction, a calling roller arranged for each paper stacking section, and a confluence of paper guide members of two vertically adjacent paper stacking sections. A separation roller pair consisting of a feed roller and a reverse roller is provided below the upper surface of the upper paper stacking section and above the lower surface of the lower paper stacking section, and a one-way clutch is provided coaxially with the feed roller. This is achieved by providing a remaining paper return member with a built-in remaining paper return member.

[Effect]

In order to achieve stable paper feeding performance, a call roller is placed for each paper stacking section, while one separation roller pair is used for both the upper and lower paper stacking sections to save space and reduce costs. We aim to make this possible.

Furthermore, by providing a remaining paper return member with a built-in one-way clutch coaxially with the feed roller of the separation roller pair, even if transfer paper remains in the nip of the separation roller pair, it can be returned to its original state.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a front vertical sectional view of a paper feeding device according to an embodiment of the present invention.

The paper stacking tray is of a so-called front loading type that is pulled out toward the front, and the upper tray 1 and lower tray 2 can be pulled out toward the front using left and right rails 3 as guides.

A bottom plate lifting lever 4.5 for pushing up the paper between the trays to a certain position and pink up rollers (calling rollers) 6 and 7 for calling up the paper from within the tray are arranged in the upper and lower stages, respectively. Downstream of the pick-up roller 6゜7, there is a conveyance path formed by an upper guide plate 8, a middle guide plate 9, and a lower guide plate 1 (H), and a pair of separation rollers of a friction separation type is installed at the confluence of the defined conveyance paths. (Feed roller 1 and reverse roller 12
) are located. As for the movement of the paper, the paper picked up by the upper or lower pickup roller 6.7 passes between the upper guide plate 8 and the middle guide plate 9 or between the middle guide plate 9 and the lower guide plate 100, and then passes through the feed roller 11 and the reverse direction. The paper reaches the nip of the rollers 12, where, if there are two or more sheets, it is separated into one sheet and sent further downstream.

FIG. 2 is a partially enlarged view, FIG. 3 is a schematic view of the upper and lower bottom plate upper boundary mechanisms, and FIG. 4 is a plan view of the bottom plate lifting mechanism. A sector gear 13 is arranged on the rotation center axis of the upper bottom plate lift lever 4, and a worm 16 is provided on the output shaft of the lift motor 15.
The lift motor 15 is drivingly connected to the sector gear 13 via. On the other hand, a sector gear 14 is also disposed on the rotation center axis of the upper bottom plate lifting lever 5, and the reduction gear 2 is arranged similarly to the upper stage.
1.22.23 with the lifting motor ohm 16. Gears 7 and 21 have built-in one-way clutches. When moving the lower bottom plate lift lever 5, the lift motor I5 is rotated so that the thrust of the worm gear acts in the {circle around (2)} direction.

As a result, the gear 21 rotates clockwise, the built-in one-way clutch engages the shaft 26, and the drive is transmitted to the gear 22. Subsequently, the sector gear 14 is rotated clockwise through the gear 23 and the sector gear 24. On the other hand, the gear 17 is rotated counterclockwise by the worm 16, but since the built-in one-way clutch is in the overrun direction, no rotation is transmitted to the shaft 25.

When moving the upper bottom plate lift lever 4, use the lift motor 1.
5 in the opposite direction to generate a thrust in the ■ direction in the worm 16, the gear 17 is rotated clockwise,
Similarly to the above, the signal is transmitted to the sector gear 13 via the gears 18, 19, and 20.

At this time, the one-way clutch of the gear 21 is in overrun, and no drive is transmitted to the lower stage.

FIG. 5 shows a front view of the pickup roller vertical movement means, and FIG. 6 shows a top view thereof.

A joint 32 is attached to the tip of the plunger of the solenoid 30 so as to be rotatable with respect to the lever 31. The lever 31 is rotatable about the pin 34, and one end of the lever 31 is in contact with the end pin 33a of the upper relay lever 33, and the other end is in contact with the end pin 36a of the lower relay lever 36. Relay levers 33, 36 each have bins 35, 40
It is rotatable around , and supports shafts 41 and 42 that are integral with the pickup arm from below (see also Fig. 2). At the tip of the shaft 41, 42 there is an upper limit detection sensor 47,
A shielding lever 45, 46 that shields the optical axis of 48 is fixed.

Figure 7 is a top view of the inside of the upper tray, Figure 8 is the X in Figure 7.
- An X-ray sectional view and FIG. 9 are perspective views of essential parts of the tray. There is a cassette 50 in which A4-sized paper can be placed in the tray 1, and a boss 56 protrudes toward the tray 1 at the center of the bottom surface of the cassette 50 (the center position of the A4-sized paper). On the other hand, on the tray 1 side, a rib 53 protrudes toward the cassette 50 side. A bearing member 57 with a collar is fitted between the boss 56 and the rib 53, and by fixing a grip ring 59 to the tip of the boss 56, the tray 1 and the cassette 50 are
is configured to be rotatable via a bearing member 57.

On the other hand, another boss 55 is formed on the lower surface of the back right corner (upper right corner in FIG. 7) of the cassette 50 in the direction of the tray 1, and the boss 55 is rotatably fitted into the end hole 54a of the lever 54. are doing. A portion 54b of the lever 54 engages with a guide groove 60 on the right side of the tray 1, making it slidable (
Figure 9).

Next, the operation of each part and the accompanying movement of the paper will be shown.

<When sending out the paper in the lower tray and the tray 2> When it is detected that the tray 2 is set in the main body (by a tray detection filler and a sensor (not shown)), the lift motor 15 rotates and the gears 21, 22, 23 Sector gear 14 via .24
and rotate the bottom plate lift lever 5 to raise the tray 2.
Lift up the paper inside from the bottom. At this time, the solenoid 30 is also energized, the lever 31 is placed in the state indicated by the dashed line in FIG. 5, and the lever 36 is rotated counterclockwise about the bin 40. Along with this, the shaft 42 and the pickup roller 7 are also lowered. When the pickup roller 7 is lowered, the shielding lever 46 shields the optical axis of the detection sensor 48.

As the paper in the tray 2 rises due to the rotation of the bottom plate lift lever 5, the top surface of the paper comes into contact with the downwardly lowered pickup roller 7, and as the roller 7 is lifted, the shaft 42 integrated with the roller 7 also rises, and the shielding lever 46 also rotates clockwise. When the shielding lever 46 rotates to a position where it does not shield the optical axis of the detection sensor 48, the driving of the lifting motor 15 is stopped, and the lifting of the paper is also stopped. Next, the energization to the solenoid 30 is stopped, the lever 31 returns to the solid line position in FIG. 5, and the pickup roller 7 also leaves the plane of the paper.

At the same time as the print button is turned on, the drive system starts moving, and the pickup roller 7 directly connected to the drive system also starts rotating. Next, the solenoid 30 is turned on and the pickup roller 7 falls onto the paper surface again, so that the paper is sent out. The fed paper passes between the guide plates 9 and 10, and then passes through the feed roller 1.
1. When the sheet reaches the reverse roller 12 and has been sent in multiple sheets, it is separated into one sheet and sent downstream.

<When feeding the paper in the upper tray 1> When it is detected that the tray 1 is set in the main body, the lift motor 15 rotates in the opposite direction to that for the lower tray 2, and
Bottom plate lift lever 4 via gears 17.1B and 19.20
Rotate and lift the paper. Unlike the case of the lower tray 2, the solenoid 30 is not energized, and the pickup roller 6 is lowered at this time. Therefore, similarly to the lower tray 2, the optical axis of the detection sensor 47 is rotated to a position where the shielding plate 45 does not shield it, the lifting motor 15 is stopped, and the paper position is determined.

The pickup roller 6 rotates at the same time as the print button is turned on, and the paper that comes into contact with it is sent out. The fed paper passes between the guide plates 8.9 and reaches the feed roller 11 and reverse roller 12, and if it has been fed in multiple sheets up to this point, it is separated into one sheet and sent downstream.

When the paper on the upper tray 1 is raised by the rotation of the lifting motor 15, the gear 21 that transmits the drive to the lower tray 2 side has a one-way clutch, which operates in the overrun direction and therefore idles. At this time, the gear 24 moves downward (
There is a constant force trying to rotate it (counterclockwise),
When the lift motor 15 is stopped, this force is received by the tooth surface of the worm 16, but since the motor is rotating in the opposite direction (when the upper tray is operating), it slips on one side of the shaft 26 and gear 21. , the gear 24 is lowered, and the uppermost sheet of the lower tray 2 is lowered below the paper passing position.

Conversely, when raising the lower tray 2, raise the upper tray 10.
The page goes down. Therefore, even if the pickup roller 6 is kept constantly rotating and vertical movement is performed alternately using the solenoid 30, only the paper from the selected upper or lower tray (the paper is lifted to the paper feeding position by the lift motor 15) is picked up. The paper will be sent.

When switching from upper tray 1 to lower tray 2 or from lower tray 2 to upper tray L, the last sheet fed from the tray before switching is fed two sheets (double feeding) by pickup roller 6, and is then transferred to feed roller 11 and reverse roller. If the paper is separated at 12, the leading end of the lower paper of the double feed remains slightly caught in the nip between both rollers, which causes problems in paper feeding from the tray after switching. Means for avoiding this situation will be explained based on FIGS. 0 and 11.

FIG. 10 is an enlarged view of the vicinity of the feed roller 11 and reverse roller 12, and FIG. 11 is a C view thereof.

Feed roller 1 is located near the feed roller 11 on the same axis.
A return lever 70 with a built-in one-way clutch and a boss portion having a diameter smaller than the outer diameter of the clutch is disposed.

A projection 70a is provided on a portion of the outer periphery of the boss portion of the lever 70.

70b is provided, and the protrusion 70a is movable between the rib 8a of the upper guide plate 8 and the guide plate 71. Along with this, the protrusion 70b on the opposite side also moves, and the tip of the protrusion moves along the guide of the lower guide plate 10. It enters below the surface and rotates. Further, an elastic sheet 72 is placed at the confluence of the paths from the upper tray 1 and the lower tray 2, and the feed roller 11 and the reverse roller 1
It is provided up to the vicinity of the nip of No. 2.

When the paper is being fed by the feed roller 11, the return lever 70 is in a state where the protrusion 70a is in contact with the rib 8a as shown by the solid line, and the one-way clutch and shaft are in an idle state. Next, when paper feeding is finished and the electromagnetic clutch 73 on the same axis of the feed roller is turned off, the reverse roller 12 is of a friction separation type in which rotational force is always applied in the reverse direction (counterclockwise). As the feed roller 11 rotates counterclockwise, the feed roller 11 also rotates clockwise. As a result, the protrusion 70a comes into contact with the guide plate 71, and the directional clutch and shaft rotate until they are cocked (state shown by the dashed line). At this time, the protrusion 70b pushes back the leading edge of the paper remaining in the nip portion and returns it further from the leading edge of the elastic sheet 72, so that the transport path of the paper from the tray after switching is not obstructed. When the paper is fed again, the return lever 70 returns to the solid line state due to the overrun torque of the one-way clutch.

<When rotating the direction of paper in upper tray 1 by 906>
- In the case of A4 or B5 size vertical/horizontal conversion, a cassette 50 is set in the upper tray l as shown in Fig. 7, and the bottom plate 51 inside is rotatable about one side 51a. The bottom plate lifting lever 4 rotates through a hole in the upper tray 1 and lifts the bottom plate 51. When the paper is rotated by 90 degrees to form A4 lengthwise paper, one side 52a of the bottom plate 52 becomes the fulcrum. cassette 50 to 90
To rotate the upper tray 6 times, pull out the upper tray 1 and slide the lever 54 on the back right side toward you.
5 is also pulled forward at the same time, and another boss 56 and bearing member 57 move laterally along the guide rib 53. Correspondingly, the corners X and Y of the cassette move in the direction shown in the figure, and finally reach the positions indicated by the dashed-dotted lines. If you want to change the size between A4 portrait and A4 landscape, just slide the lever 54 to the back in the opposite direction to the above.

〔Effect of the invention〕

As explained above, according to the present invention, in order to obtain stable paper feeding performance, the calling roller is arranged for each paper stacking section, and one separation roller pair is used for both the upper and lower paper stacking sections. By doing so, it is possible to save space and reduce costs.

In addition, by providing a residual paper return member with a built-in one-way clutch coaxially with the feed roller of the separation roller pair, even if transfer paper remains on the separation roller pair, it can be returned to its original state. .

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of a paper feeding device according to an embodiment of the present invention, FIG. 2 is a partially enlarged view of the paper feeding section, FIG. 3 is a configuration diagram of the upper and lower bottom plate lifting mechanisms, and FIG. 4 is a A plan view of the bottom plate lifting mechanism, FIG. 5 is a front view of the pickup roller vertical movement means, FIG. 6 is a plan view of the pickup roller vertical movement means, FIG. 7 is a plan view of the inside of the upper tray, and FIG. 8 is a front view of the pickup roller vertical movement means. 9 is a perspective view of the main part of the tray, FIG. 10 is an enlarged view of the vicinity of the feed roller and reverse roller portion, and FIG. 11 is a view from C in FIG. 10. l...Upper tray, 2...Lower tray, 6.7...Pickup roller, 11...Feed roller, 12.
...Reverse roller, 50...Cassette, 70...
Figure 2 Figure 2 Figure 10 Figure 11

Claims (1)

[Claims] a paper stacking section arranged in at least two or more stages in the vertical direction;
This is the confluence of the calling rollers arranged for each paper stacking section and the paper guide members of two vertically adjacent paper stacking sections, below the top surface of the upper paper stacking section and above the bottom surface of the lower paper stacking section. A paper feeding device comprising: a separation roller pair consisting of a feed roller and a reverse roller; and a remaining paper return member provided coaxially with the feed roller and having a built-in one-way clutch. .