JPH0940198A - Paper feeding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the reliable feed of a transfer paper without the occurrence of non-feed and a double feed even when transfer papers having a wide range of sizes and kinds of paper sheets are used. SOLUTION: The sizes of transfer papers P contained in a paper feed cassette 7 are detected by a detecting plate detection sensor 16 by means of a size detecting plate 15. According to the size of the transfer paper P, by rotating a stepping motor 24 by a control device 50 by an amount equivalent to a given pulse, a bracket 22 is moved in the direction of an arrow mark A and this movement moves a paper feed roller 6 through a support member 32 along a roller support shaft 10. In which case, a rack plate 4 formed integrally with the paper feed roller 6 is moved and a rack plate 5 engaged through a pinion 34 is moved togetherwith a paper feed roller 3. As a result, two paper feed roller 3 and 6 are moved in a reverse direction to each other to a position, corresponding to the size of the transfer paper P, along a roller support shaft 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device using a corner claw separation system.

[0002]

2. Description of the Related Art In a sheet feeding device using a corner claw separation system,
The feed roller that feeds the transfer sheet and the corner claw that presses the tip of the transfer sheet buckle the transfer sheet and separate it into one sheet. Therefore, if the distance between the feed roller and the corner claw is short, it will not feed. Is likely to occur, and if it is far, stacking (double feed) is likely to occur. Therefore, in the sheet feeding device using such a corner claw separation system, the positional relationship between the sheet feeding roller and the corner claw is extremely important. In addition, the buckling force of the paper differs depending on the type of paper, so if you try to buckle the transfer paper under optimal conditions and try to separate it into one sheet, the positions of the corner claw and the paper feed roller will depend on the type of the transfer paper. Also needs to change.

As described above, in the sheet feeding device using the corner claw separation method, it is necessary to buckle the transfer sheet under the optimum conditions. Between the paper feed roller (feed roll) and the corner pawl (corner stopper), a paper pressing member that retreats after contacting the paper in synchronization with the rotation of the paper feed roller is provided to prevent the buckling of the paper. It is proposed that different forces are applied during the loosening operation so that even if the type of paper is different, it will not cause a paper feed error, a double feed, or even damage the leading edge of the paper (for example, actual cutting flatness). No. 2-137337). There is also a transfer paper in which the size, paper thickness, and paper type are regulated, or 4 to 6 paper feed rollers are used so that various transfer paper sizes can be accommodated.

[0004]

However, if a paper pressing member is provided between the paper feed roller and the corner claw, the paper pressing member retracts after coming into contact with the paper in synchronization with the rotation of the paper feed roller. The number of parts increases between the paper roller and the corner claw, which complicates the configuration. Further, when the sizes of the transfer papers used differ greatly, there is a problem that the transfer papers cannot be buckled under the optimum conditions. Furthermore, even when 4 to 6 paper feed rollers are used so that various transfer paper sizes can be accommodated, the optimum buckling is performed to ensure that the transfer paper is separated and fed into one sheet. There is a problem in that the number of transfer papers that can be used is limited to several types, and if the size of transfer papers that can be handled is further increased, the number of paper feed rollers becomes very large.

When a plurality of paper feed rollers are arranged in the paper width direction perpendicular to the paper feed direction in correspondence with several kinds of transfer paper sizes, the paper thickness of the transfer paper used is normally all. There is no problem if the paper thickness is the one to be used, but when using transfer paper with different paper thickness and paper quality, the placement position of the paper feed roller is also decided considering the paper thickness and paper quality. However, there is a possibility that the transfer paper cannot be buckled under the optimum conditions, which may cause a paper feed failure or a double feed.

The present invention has been made in view of the above problems, and even when transfer papers of a wide range of sizes and paper types are used, the transfer papers can be reliably fed without causing non-feeding or double feeding. The purpose is to be able to make paper.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention allows a paper feed cassette to be attached to and detached from a main body of a device in a direction orthogonal to a paper feed direction of transfer paper. In the sheet feeding device used, a size detecting means for detecting the size of the transfer sheet in the sheet feeding cassette, and a direction parallel to the sheet surface of the transfer sheet in the sheet feeding cassette and orthogonal to the sheet feeding direction above the sheet feeding cassette. The roller support shafts arranged along the same direction and the roller support shafts attached to the roller support shafts are movable in the respective axial directions, and are arranged so that the distance from the transfer paper transport center in the axial direction becomes equal. Two paper feed rollers provided and a paper feed roller that moves the two paper feed rollers in positions opposite to each other along the roller support shaft to a position corresponding to the size of the transfer paper detected by the size detection means. With means of transportation It is.

With this configuration, the size of the transfer paper stored in the paper feed cassette is detected by the size detecting means, and two paper feed rollers are supplied corresponding to the detected size of the transfer paper. Since the paper roller moving means move in the opposite directions along the roller support axis so that the distance from the transport center of the transfer paper becomes equal, the moving position can be adjusted under optimum conditions corresponding to the size of the transfer paper. By setting it to a position where it can be buckled, it is possible to reliably feed transfer paper of a wide range of sizes without causing a paper feed failure or double feeding.

Further, in the above-mentioned paper feeding device, a paper thickness detecting means for detecting the paper thickness of the transfer paper in the paper feeding cassette is provided, and the paper feed roller moving means is a transfer device which is detected by the paper thickness detecting means. Depending on the paper thickness of the paper, the two paper feed rollers may be moved in the opposite directions along the roller support shaft. By doing so, in addition to the size of the transfer paper, the two paper feed rollers can be moved to the optimum position for paper feed along the roller support shaft in consideration of the type of paper thickness of the transfer paper. Even thick or thin transfer paper can be reliably fed without causing paper feeding failure or double feeding.

[0010]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a side view showing a sheet feeding device for explaining an embodiment of the invention.
In this paper feeding device 1, a paper feeding cassette 7 is removably inserted in a main body structure 2 which constitutes the main body of the device in an arrow A direction orthogonal to a paper feeding direction of transfer paper (frontward in the drawing). ing.
Further, inside the paper feeding cassette 7, there are provided corner claws 8 and 9 for buckling by pushing both end portions of the front end of the fed transfer paper P to separate them into one sheet. The main body structure 2 is composed of a bottom plate 17, a front plate 20, a rear plate 18, and a stay 21, and the paper feed cassette 7 is removably inserted in the arrow A direction on the bottom plate 17.

On the inner wall surface 7a of the paper feed cassette 7, a size detecting plate 15 having a different shape corresponding to each size of the transferred transfer paper P is fixed and is made to correspond to the size detecting plate 15. A detection plate detection sensor 16 (transmission type photo sensor) that is a size detection unit that detects the size of the transfer paper P in the paper feed cassette 7 is fixed to the rear side plate 18. As a result, when the paper feed cassette 7 is inserted into the position shown in FIG. 1, the detection portion of the detection plate detection sensor 16 is shielded from light in accordance with the shape of the size detection plate 15, so that the transfer in the paper feed cassette 7 is performed. The size of the paper P can be detected.

The corner claws 8 and 9 provided on the paper feeding cassette 7 are a pair of side fences 12 and 13 which can approach and separate from each other in the direction of arrow A according to the size of the transfer paper P.
Attached to each. A bottom plate 11 which is biased upward by a spring 14 is provided in the paper feed cassette 7 with a rear end rotatably supported so that the front end moves up and down. 14
The uppermost one of the transfer sheets P placed on the bottom plate 11 by the biasing force of (3) comes into pressure contact with the sheet feeding rollers 3 and 6 with a pressing force suitable for sheet feeding.

Above the paper feed cassette 7, there is provided a roller support shaft 10 extending parallel to the paper surface of the transfer paper P in the paper feed cassette 7 and extending in the direction of arrow A orthogonal to the paper feed direction. The roller support shaft 10 is rotatably held by the front side plate 20 and the rear side plate 18 via bearings 31, 31. In the roller support shaft 10, the central shaft portion 27 is formed of a plate-shaped member having a U-shaped vertical cross-section, and the round shaft portion 28 is formed with angular shaft portions 28a and 29a at both ends thereof. , 29
Are fixed by screws and are integrally formed. Then, the two feeding rollers 3 and 6 each having a half-moon shape are formed on the central shaft portion 27 so that the distances from the transport center CL of the transfer paper P in the axial direction (direction of the arrow A) are equal. It is attached so that it can be moved.

One of the paper feed rollers 6 is fixed to the rack plate 4, and the other paper feed roller 3 is fixed to the rack plate 5. Then, the rack portion 4a of the rack plates 4 and 5
And 5a are engaged with the pinion 34 which is rotatably supported by the central shaft portion 27. Therefore, when the paper feed roller 6 moves in the arrow A direction, the pinion 34 rotates, so that the rack plate 5 in which the rack portion 5a meshes with the pinion 34 moves in the arrow A direction and is integrated with the rack plate 5. Paper feed rollers 3 are closer to paper feed rollers 6
Move in the direction of separation (opposite direction).

The round shaft portion 29 on the side of the rear plate 18 of the roller support shaft 10 has a shaft 1 for transmitting a rotational force to the paper feed rollers 3 and 6.
The rotary shaft of the rotary clutch 19 is attached, and the one rotary clutch 19 is connected to a main motor (not shown) by a gear. A supporting member 32 is fixed to the paper feeding roller 6, and the L-shaped bracket 2 is attached to the supporting member 32.
One end of 2 is fixed.

As shown in FIG. 2, the bracket 22 is formed with two long holes 22a and 22b at intervals along the longitudinal direction, and the respective long holes 22a and 22b are formed.
Stepped screws 23, 23 are respectively fitted into the screws, and the tips of the stepped screws 23 are fixed to the stay 21 (see FIG. 1). Therefore, the bracket 22 includes the long holes 22a, 2
The end of 2b slides in the direction of arrow B in FIG.

At the rear of one side edge of the bracket 22,
The rack portion 22c is formed, and the rack portion 22c is formed.
The pinion 35 fixed to the rotary shaft of the stepping motor 24 fixed to the stay 21 (FIG. 1) meshes with the shaft. Therefore, when the stepping motor 24 is rotated, the bracket 22 moves in the arrow B direction, and the paper feed roller 6 moves in the same direction accordingly. Then, when the paper feed roller 6 moves, the pinion 34 rotates, so that the rack 5 in which the rack portion 5a meshes with the pinion 34 moves in the arrow B direction. As a result, the paper feed roller 3 integrated with the rack 5 moves in a direction of approaching and separating from the paper feed roller 6. The bracket 22 is formed with a light shielding piece portion 22d by widening the plate width, and the bracket detecting sensor 2 is made to correspond to the light shielding piece portion 22d.
5 (transmission type photo sensor) is fixed to the rear side plate 18.

FIG. 3 is a perspective view showing a size detecting plate and a paper thickness detecting plate which are attached to the inner wall surface of the paper feeding cassette together with the detecting plate detecting sensor. In this paper feeding device, in addition to the size detection plate 15 corresponding to the size of the transfer paper described in FIG. 1, the paper thickness as shown in FIG. 4 in which the shape is different corresponding to the paper thickness of the transfer paper. The detection plates 26A to 26C are prepared.

The paper thickness detection plates 26A to 26C are formed on a wall surface 7a (see FIG. 1) on the back side of the paper feed cassette 7 in accordance with the paper thickness of the transfer paper stored in the paper feed cassette 7. When the transfer paper to be stored has a small paper thickness, the paper thickness detection plate 26A for the thin paper is used.
If the paper thickness is normal, the paper thickness detection plate 26B for plain paper
If the paper thickness is thick, the paper thickness detection plate 26C for thick paper is used. Then, the paper thickness detection plates 26A to 26
In C, the detection plate detection sensor 16 (FIG. 3) detects each of the detection units 26a, 26b, and 26c, and the detection units 26a, 26b, and 26c have shapes as shown in FIG. Paper thickness detection plates 26A, 26B, 26
C is different for each.

By the way, in this paper feeding device, as shown in FIG. 1, the two paper feeding rollers 3 and 6 are mounted on the roller support shaft 10 at a position corresponding to the size of the transfer paper detected by the detection plate detection sensor 16. Control device 5 for moving in opposite directions along
It has 0. That is, in the embodiment of the present invention, the control device 50 moves the two paper feed rollers in positions opposite to each other along the roller support shaft to a position corresponding to the size of the transfer paper detected by the size detection means. It functions as a control unit of the paper feed roller moving means.

In the control device 50, the detection plate detection sensor 16 has the paper thickness detection plate 26A (or 26B, 26C).
Depending on the paper thickness of the transfer paper P in the paper feed cassette 7 which is determined by the detection, the control for moving the two paper feed rollers 3 and 6 in the opposite directions along the roller support shaft 10 is also performed. The control device 50 includes a central processing unit (CPU) having various judgment and processing functions, a ROM that stores each processing program and fixed data, a RAM that is a data memory that stores the processing data, and an input / output circuit (I / O) and a microcomputer.

The control device 50 includes a detection plate detection sensor 1
6, a transfer paper size signal corresponding to the size of the transfer paper P stored in the paper feed cassette 7, and a paper thickness detection plate 26A.
By inputting (or 26B, 26C), a transfer paper thickness signal corresponding to the paper thickness of the transfer paper is input. In addition, an ON / OFF signal that changes depending on the position of the light shielding piece portion 22d (FIG. 2) of the bracket 22 is input from the bracket detection sensor 25. Then, a drive signal for rotating the stepping motor 24 by a set pulse corresponding to the size of the transfer sheet P in the sheet feeding cassette 7 is output at a predetermined timing.

When the paper feed cassette 7 is inserted into a predetermined position of the main body structure 2 as shown in FIG. 1, the microcomputer of the controller 50 moves the paper feed roller shown in FIG. 5 at a predetermined timing. Start the processing routine. First, in order to accurately position the paper feed rollers 3 and 6 in the left-right direction in FIG. 1, it is determined in step 1 whether the bracket 22 is at the home position shown in FIG.
Is determined to be ON (when the light shielding of the detection unit is released and is ON).

If it is not turned on, in step 2, the stepping motor 24 is rotated in the reverse direction to move the bracket 22 to the right in FIG. 2 until the bracket detection sensor 25 is turned on, and the bracket 22 is moved to the home position. Return to step 3 and proceed to step 3. Also, the bracket 22 from the beginning
If is in the home position and the bracket detection sensor 25 is turned on, the process directly proceeds to step 3, the stepping motor 24 is rotated forward, and it is determined in step 4 that the bracket detection sensor 25 is turned off. Then, in step 5, the stepping motor 24 is rotated forward by a pulse Fo, which will be described later, and then stopped in step 6, and then the process returns to the main routine.

The pulse Fo is a pulse F determined by the size of the transfer paper stored in the paper feed cassette 7.
And Fo = F + F 'obtained by the pulse F'determined by the paper thickness of the transfer paper. The size and paper thickness of the transfer paper are determined by the above-mentioned detection plate detection sensor 16 such as the size detection plate 15 and the paper thickness detection plates 26A to 26A.
Judgment is made based on the signal output by detecting C (FIG. 4).

A pulse F according to the size of the transfer paper,
The pulse F'according to the paper thickness will be described below.

In this way, the transfer paper P in the paper feed cassette 7 detected from the home position shown in FIG. 2 by the detection plate detection sensor 16 described in FIG.
According to the size and the paper thickness of the transfer sheet, the stepping motor 24 is rotated by the normal rotation by the set pulse of the Fo, whereby the paper feed rollers 3 and 6 are optimally moved according to the size and the paper thickness of the transfer paper. Since the sheet is moved to the position, it is possible to reliably separate and feed the transfer sheets of a wide range of sizes without causing a paper feed failure or a double feed.

The paper feed rollers 3 and 6 are moved by the stepping motor 24 being rotated by a preset pulse of Fo, which is set in consideration of the paper thickness of the transfer paper. It is possible to reliably feed even the above transfer paper without causing a paper feed failure or a double feed.

[0029]

As described above, according to the present invention, the size of the transfer paper in the paper feed cassette is detected, and the transfer paper of that size can be separated and fed one by one to the optimum position. Since it is possible to move the individual paper feed rollers, it is possible to reliably feed transfer paper of a wide range of sizes without causing a paper feed failure or a double feed.

Further, a paper thickness detecting means for detecting the paper thickness of the transfer paper in the paper feeding cassette is provided, and the paper feed roller moving means detects the paper thickness of the transfer paper detected by the paper thickness detecting means. However, if the two paper feed rollers are moved in opposite directions along the roller support shaft, the two paper feed rollers can be placed at the optimum positions in consideration of the transfer paper size as well as the transfer paper size. Since the paper feed roller of can be moved,
Regardless of whether it is thin paper, reliable paper feeding can be performed without causing a paper feed failure or double feeding.

[Brief description of drawings]

FIG. 1 is a side view showing a sheet feeding device for explaining an embodiment of the invention.

FIG. 2 is a plan view showing two paper feed rollers provided in the paper feeder of FIG. 1 and a mechanism for moving them.

FIG. 3 is a perspective view showing a size detection plate and a paper thickness detection plate attached to the wall surface of a paper feed cassette together with a detection plate detection sensor.

FIG. 4 is a perspective view showing three types of paper thickness detection plates for thin paper, for normal paper thickness, and for thick paper.

5 is a flow chart showing a routine of paper feed roller movement processing performed by a microcomputer included in the control device 50 of FIG.

[Explanation of symbols]

 1: Paper feeding device 2: Main body structure 3,6: Paper feeding roller 7: Paper feeding cassette 8,9: Corner claw 10: Roller support shaft 15: Size detection plate 16: Detection plate detection sensor 22: Bracket 22c: Rack Part 24: Stepping motor 26A, 26B, 26C: Paper thickness detection plate 34, 35: Pinion

Claims (2)

[Claims] 1. A sheet feeding device using a corner claw separation method, wherein a sheet feeding cassette is detachably attached to a main body of the apparatus in a direction orthogonal to a sheet feeding direction of the transfer sheet. A size detecting means for detecting the size of the roller, and a roller support shaft disposed above the paper feeding cassette in parallel with the paper surface of the transfer paper in the paper feeding cassette and in a direction orthogonal to the paper feeding direction. , Two paper feed rollers mounted on the roller support shaft and movable in the respective axial directions, and arranged so that the distance in the axial direction from the transport center of the transfer paper is equal, And a paper feed roller moving means for moving the individual paper feed rollers in positions opposite to each other along the roller support shaft at positions corresponding to the size of the transfer paper detected by the size detection means. Paper feeder. 2. The paper feeding device according to claim 1, wherein a paper thickness detecting means for detecting the paper thickness of the transfer paper in the paper feeding cassette is provided, and the paper feeding roller moving means is provided with the paper thickness. A sheet feeding device characterized in that the two sheet feeding rollers are moved in mutually opposite directions along the roller supporting shaft according to the sheet thickness of the transfer sheet detected by the detecting means.