JPH06271104A - Paper feed device for image forming device - Google Patents

Abstract

PURPOSE:To provide a paper feed device in which switching from paper feed by a cassette to multi-paper feed or vice versa can be optionally performed, and which is capable of ensuring an installation space for the cassette sufficient ly and of changing the cassette loaded on a paper feed tray optionally depending on the desired paper size. CONSTITUTION:A cassette is loaded on a frame-like paper feed unit 10 so that it can be loaded and unloaded. In the paper feed unit 10, a multi-paper feed tray 50, on which a number of printing paper sheets are placed, is provided so that it can move up and down, and a pair of fences 61, 61 capable of adjusting the placed printing paper sheets in the widthwise direction are provided. Changing the size of the printing paper sheets placed on the multi-paper feed tray 50 is performed by moving the pair of fences 61, 61 in the crosswise direction of the printing paper sheets, and restricting the positions of both side edges of the recording paper sheets. When the paper feeding is switched to the paper feed by the cassette, the fences 61, 61 are provided in the paper feed unit 10, and thus the fences do not interfere with the installation of the cassette. A sufficient installation space for the cassette can thus be ensured.

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 for feeding a recording sheet to an image forming apparatus such as a copying machine or a printing machine.

[0002]

2. Description of the Related Art In an image forming apparatus, it is often the case that a large number of images are continuously recorded (a large number of sheets are fed) using the same recording paper. However, there may be a case where it is desired to interrupt the recording of a large number of images and record a small number of images (cassette feeding) using another recording sheet. Therefore, some of the conventional sheet feeding devices attached to the image forming apparatus have a structure to meet such a demand.

FIGS. 8A and 8B are perspective views showing an example of the construction of an image forming apparatus provided with a sheet feeding device so that the above-described multi-sheet feeding and cassette sheet feeding can both be performed. In the figure, a sheet feeding device 91 attached to a side portion of the image forming apparatus 90 includes a frame 92 that can be pulled out and stored in the apparatus body 91a, and a sheet feeding pickup roller 93 that is provided on an upper side surface of the frame 92. And the pickup roller 93
A large number of recording papers 9 that move up and down in the frame 92 with respect to
A sheet feeding table 95 on which the sheets 4 are stacked and a sheet guide 96 provided on the frame 92 and adjustable in the length direction of the recording sheet 94 on the sheet feeding table 95 are provided. Also, the cassette 97
In addition to the sheet feeding device 91 for feeding a large number of sheets, the sheet feeding device is provided so that it can be pulled out and stored for each sheet size of the recording sheet in the image forming apparatus 90.

In the above-mentioned apparatus, a dedicated pickup roller (only the roller for feeding a large number of sheets is shown) in the vicinity of the sheet feeding table 95 for feeding a large number of sheets and each cassette 97, respectively. It has a paper feed mechanism composed of a separating plate or the like, and one of the paper feed mechanisms corresponding to the paper selection by the operator operates to select the recording paper 94 on the paper feed tray 95 or the recording paper in the cassette 97. It is designed to be sent out in a unitary manner and guided to a predetermined position in the image forming apparatus 90.

[0005]

The above-described conventional paper feeding device has paper feeding mechanisms corresponding to the number of paper feeding bases 95 or cassettes 97 that can be set in advance, and further the recording paper fed from each roller is common. It has a plurality of conveying paths for leading to the sheet feeding position. For this reason, there is a problem that the structure is complicated and large, and a paper feeding trouble is likely to occur.

In order to solve this problem, the inventor of the present application has
The idea of a paper feed device in which a paper feed mechanism is provided at a single location, and either a multi-paper feed table capable of accommodating a large number of recording sheets or the cassette is movable to the position of the paper feed mechanism I arrived.

However, in this paper feeding device, since the multi-sheet feeding table and the cassette move to the same paper feeding position in the paper feeding mechanism portion, one operation interferes with the other operation. Need to be considered.

Further, by making the cassette detachable, the above-mentioned interruption work can be facilitated. In this case, however, a sufficient installation space for the cassette can be secured and the cassette can be mounted on the paper feed tray according to the desired paper size. It is required to have a configuration in which the cassette to be placed can be changed arbitrarily.

According to the present invention, sheet feeding by a cassette and sheet feeding of a large number of sheets can be arbitrarily switched, a sufficient installation space for the cassette can be secured, and the sheet can be placed on a sheet feeding table according to a desired sheet size. The cassette to be changed can be changed arbitrarily,
An object of the present invention is to provide a small-sized and simple-structured paper feeding device that can arbitrarily change the paper size of a large number of recording papers.

[0010]

In order to achieve the above-mentioned object, a paper feeding apparatus according to a first aspect of the present invention is one in which a stack of recording sheets is taken out one by one at a fixed position and sent out to an image recording section. A pair of sheet feeding mechanism, a sheet feeding unit that can move up and down with respect to the sheet feeding mechanism, and a sheet feeding unit that is provided above the sheet feeding unit and avoids the sheet feeding mechanism when vertically moving together with the sheet feeding unit. A first paper feed tray having a cutout portion through which it can pass; a second paper feed tray provided below the first paper feed tray so as to be vertically movable in the paper feed unit; and the paper feed unit And a pair of fences provided inside thereof for restricting the positions of both side edges of the recording paper placed on the second paper feed table.

The sheet feeding device according to the second aspect of the invention is capable of moving up and down, and a set of sheet feeding mechanisms for picking up the stacked recording sheets one by one at a fixed position toward the image recording section. A sheet feeding unit, provided on the upper side of the sheet feeding unit,
A first paper feed table having a notch portion through which the recording mechanism can be passed when moving up and down of the paper feed mechanism together with the paper feed unit, and a cassette containing the recording paper can be attached to and detached from the upper surface. And a second paper feed table which is vertically movable in the paper feed unit below the first paper feed tray and has recording paper stacked on its upper surface, and a second paper feed tray mounted on the second paper feed table. A pair of fences is provided in the paper feeding unit so as to be movable and adjustable according to the size of the recording paper to be placed, and a pair of fences that regulate the positions of both side edges of the recording paper.

[0012]

When the cassette is fed, the vertically movable sheet feeding unit is set so that the cassette stand is located below the sheet feeding section. The paper feed unit is set so that the first paper feed tray located above it is located below the paper feed mechanism. A cassette is installed on the first paper feed tray, and the recording paper in the cassette is sent out to the image forming apparatus by the paper feed mechanism. When feeding multiple sheets,
The cassette is removed, and the paper feeding unit is raised so that the first paper feeding tray is located above the paper feeding mechanism. When the sheet feeding unit moves up, the sheet feeding mechanism passes through the cutout portion of the first sheet feeding tray and does not interfere with the sheet feeding unit. The recording paper on the second paper feed tray is sent to the image forming apparatus by the paper feed mechanism. When changing the size of the recording paper placed on the second paper feed tray, place the recording paper of the desired size on the second paper feed tray and move the pair of fences to move the recording paper on both sides. Regulate the edge position. In addition, since the fence is installed in the paper feed unit, even if the paper feed is switched from the second paper feed tray to the paper feed by the cassette, the fence does not interfere with the installation of the cassette and the installation space is sufficient. Can be secured.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The sheet feeding device 1 of this embodiment shown in FIG. 1 is an example incorporated in a stencil printing device 2. The paper feed mechanism 3 provided on the printing device 2 side is provided with a pickup roller for taking in the printing paper of the paper feed device 1. The paper feeding device 1 vertically moves a cassette in which printing papers are stored and printing papers stacked on a table to position one of them in the paper feeding mechanism 3 and supplies a desired paper to the printing device 2. be able to.

As shown in FIGS. 2 and 3, the sheet feeding device 1 has a substantially box-shaped frame 6 composed of a pair of left and right side plates 4 and 4 and a bottom plate 5. The upper ends of the pair of side plates 4 and 4 are fixed and connected by a rod 7.

As shown in FIG. 4, a motor 8 which is a drive source of this apparatus is provided below the outer surface of one side plate 4. The motor 8 is linked to an input shaft of a gear box 9 having a reduction gear and a clutch. The gear box 9 has two drive shafts A and B as output shafts. The drive shafts A and B are parallel to each other and are rotatably provided between the pair of side plates 4 and 4 at a predetermined interval.

As shown in FIGS. 2 to 3, a substantially box-shaped sheet feeding unit 10 is provided in the frame 6 so as to be vertically movable. The paper feeding unit 10 has a configuration in which a lower base plate 11 and an upper cassette base 12 which is a first paper feed base are connected by a pair of side plates 13 and 13. A cassette K containing print sheets is placed on the upper cassette table 12 (see FIG. 7B). When performing continuous printing of a large number of sheets without using the cassette K, the cassette K is removed and the entire sheet feeding unit 10 is set at a predetermined upper position as described later. As shown in FIGS. 1 and 2, the cassette base 12 is provided with a notch 14 for avoiding the pickup roller so that the pickup roller 3 does not interfere.

As shown in FIG. 2, the side plates of the frame 6 are formed with guide grooves 15 and 16 which are parallel to each other in the vertical direction. In one guide groove 15, a roller 70 rotatably provided on the side surface of the base plate 11 is vertically movably fitted, and in the other guide groove 16, a roller 70 is rotatable on the side surface of the cassette table 12. The roller 71 provided in the above is loosely fitted so as to be vertically movable.

A take-up pulley 17 is provided at the end of the drive shaft A protruding outward from the side plate 4. An intermediate pulley 18 is provided on the side plate 4 above the guide groove 15. One end of a wire 19 is connected to the peripheral surface of the winding pulley 17, and the wire 19 is connected to the intermediate pulley 18
The other end is connected to the roller 70.

Therefore, if the motor 8 drives the drive shaft A to wind the wire 19 around the winding pulley 17,
The roller 70 is pulled upward by the wire 19, and the paper feeding unit 10 rises in the frame 6 along the guide grooves 15 and 16. Further, when the drive shaft A is rotated in the reverse direction, the wire 19 wound around the winding pulley 17 is unwound, and the sheet feeding unit 10 is lowered by its own weight. That is, the entire box-shaped paper feeding unit 10 can be raised and lowered within the frame 6.

As shown in FIGS. 2 to 5, an adjusting shaft 20 is provided above the base plate 11 of the paper feeding unit 10 in parallel with the drive shafts A and B. The adjusting shaft 20 is rotatably provided between the side plates 13 of the paper feeding unit 10. One end of the adjustment shaft 20 protrudes outward from a groove 21 provided in one side plate 4 of the frame 6 along the longitudinal direction, and a pulley 22 is provided at the protruding one end. . A screw portion 23 is provided at the center of the adjusting shaft 20.

A plate-shaped lower fence base 24 is provided between the base plate 11 of the paper feeding unit 10 and the adjusting shaft 20. The adjustment shaft 20 has right and left edges 24a, 24a of the lower fence base 24 inserted through slide bushes 25, and the screw portion 23 of the adjustment shaft 20 is fixed to the upper surface of the lower fence base 24 by a fixture 26. It engages with the screw receiver 27 that is formed. Therefore, when the adjustment shaft 20 is rotated, the lower fence base 24 can be moved in the axial direction within the paper feeding unit 10.

A mechanism similar to the moving mechanism of the lower fence base 24 described above is also provided below the cassette base 12 of the paper feeding unit 10 as shown in FIG. That is, the screw portion 29 of the adjustment shaft 28 is fixed to the upper fence base 30 by the fixing member 31.
It engages with the screw receiver 32 fixed by. Reference numeral 33 is a slide bush, and 34 is a pulley. As shown in FIG. 2, the upper adjusting shaft 28 is also inserted through the groove 35 provided in the side plate 4.

As shown in FIG. 3, the upper fence stand 30
The lower fence base 24 and the lower fence base 24 are connected by a guide shaft 40. A timing belt 41 is wound around the pulley 34 of the upper fence stand 30 and the pulley 22 of the lower fence stand 24. And the adjustment axis 2 of the upper fence stand 30
A dial 42 as an operation unit is provided on the control unit 8 so that the adjusting shaft 28 can be manually rotated.

Therefore, when the upper adjusting shaft 28 is rotated by turning the dial 42, the lower adjusting shaft 20 is simultaneously rotated by the pulleys 34 and 22 and the timing belt 41. The upper fence base 30 and the lower fence base 24 connected by the guide shaft 40 serve as a horizontal positioning mechanism for a multi-sheet feed base 50 described later in FIG.
You can adjust the position to the left and right inside.

As shown in FIG. 3, the sheet feeding unit 10
Below the cassette table 12, a multi-sheet feeding table 50 as a second sheet feeding table is provided so as to be vertically movable.
The multi-sheet feeding table 50 has an upper plate 51 on which a large number of stacked printing sheets are placed, and a lower plate 52 that movably supports the upper plate 51.

Guide members 54 are provided on both sides of the upper plate 51. The guide shaft 40 is inserted through each of the guide members 54, and the upper plate 51 can be moved up and down along the guide shaft 40.

As shown in FIGS. 2 and 3, the lower plate 52 is
At both ends of the support shaft 53 fixed to the
Is provided. As shown in FIG. 2, the side plate 4 of the frame 6 is formed with two vertical guide grooves 56, 56, and the roller 55 of the support shaft 53 is movably engaged with the guide groove 56. A winding pulley 57 is provided at the end of the drive shaft B protruding outward from the side plate 4. An intermediate pulley 5 is provided on each of the side plates 4 above the guide grooves 56, 56.
8, 58 are provided. One end of each of the two wires 59, 59 is connected to the peripheral surface of the winding pulley 57,
The two wires 59, 59 are wound around different intermediate pulleys 58, 58, and the other ends of the two wires 59, 59 are connected to the two rollers 5.
5 and 55, respectively.

Therefore, the motor 8 drives the drive shaft B to
When the wires 59, 59 of the book are wound around the winding pulley 57, the rollers 59 are pulled upward by the wire 59, and the lower tray 52 is moved along the guide shaft 40.
It rises within 0. When the drive shaft B is reversed, the wire 59 wound around the winding pulley 57 is unwound and the lower tray 52 is lowered by its own weight.

The drive shafts A and B, and the drive mechanism for the sheet feed unit 10 and the multi-sheet feed tray 50 using wires and pulleys are omitted in FIG. It is also provided on the side plate 4.

As shown in FIG. 3, a plurality of bearings 60 are provided on the lower tray 52. An upper plate 51 is movably provided on the bearings 60. The upper plate 51 is vertically movable along the guide shaft 40 and horizontally movable along the support shaft 53. Therefore, when the dial 42 is turned to move the upper and lower fence stands 30 and 24 in the horizontal direction, the upper tray 51 of the multi-sheet feed stand 50 moves along the support shaft 53.

As shown in FIGS. 3 to 5, two fences 61, 61 are provided between the upper and lower fence stands 30, 24 so as to be movable in the horizontal direction. That is, as shown in FIG. 5, a slider 73 is slidably supported by two parallel guide shafts 62 fixed to the lower fence base 24, and the lower portion of the fence 61 is fixed to the slider 73. , The fence 61 and the slider 73 together with the guide shaft 6
Can move along 2. Although not shown, the upper fence base 30 and the upper portion of the fence 61 also have similar mechanisms. Further, although not shown, a fixing means is provided so that the position of the fence 61 can be fixed.

As can be seen by comparing FIG. 1 and FIG. 2, the mechanism outside the side plates 4 and 4 has covers 63a and 63a.
Is covered by. As shown in FIGS. 1 and 6, one cover 63a has a narrow portion corresponding to the diameter of the adjustment shaft 28 such that the adjustment shaft 28 can move up and down, and the cover 63a with the dial 42 attached to the adjustment shaft 28. A substantially convex opening 64 having a wide portion corresponding to the diameter of the dial 42 is provided so as to be removable from the device 1.
The wide portion and the narrow portion of the opening 64 are covered with a cover 65 and a lid 66 that bulge outward and form a storage space for the dial 42. The cover 65 is formed integrally with the cover 63a, but the lid 66 is formed of a transparent or translucent member, and is supported by the hinge 72 to be openable / closable with respect to the cover 65.

A multi-sheet mode is selected by a mode selector switch (not shown), and the sheet feeding unit 10 is raised to move the sheets on the multi-sheet feeding table 50 to below the sheet feeding mechanism 3 as shown in FIG. 7A. When positioned (when feeding multiple sheets),
As shown in (a), since the dial 42 is located in the narrow portion of the opening 64, the dial 42 can be seen from the outside through the transparent lid 66. When the lid 66 is opened, the dial 42 can be manually rotated. can do. Further, when the cassette paper feed mode is selected by a mode switch (not shown) and the paper feed unit 10 is lowered to position the paper in the cassette K below the paper feed mechanism 3 as shown in FIG. 7B ( When the cassette is fed, the dial 42 is located in the wide portion of the opening 64 and hidden behind the cover 65 as shown in FIG. 6B.

As shown in FIG. 1, an openable / closable lid 67 is provided on the front side of the apparatus 1. In this device 1, the respective parts cannot be driven and moved up and down unless the lid 67 is closed, and safety during operation is ensured.

In the above construction, when it is desired to perform continuous printing of a large number of sheets, the multi-sheet feeding mode is selected, and the sheet feeding unit 10 is raised without mounting the cassette on the cassette table 12, and the sheet feeding unit 10 shown in FIG. ) Cassette stand 1 as shown in
2 is positioned above the paper feed mechanism 3. Since the cassette base 12 is provided with the cutout portion 14, the entire paper feed unit 10 including the cassette base 12 can be raised without interfering with the paper feed mechanism 3. Then, the paper feeding unit 10 is positioned so that the pickup roller of the paper feeding mechanism 3 comes into contact with the upper surface of the printing paper 68 placed on the multi-paper feeding table 50 with a predetermined pressure from above. After the printing is started, the paper feed mechanism 3 takes out the printing papers 68 one by one from the uppermost one and sends them to the printing apparatus 2. Take-up pulley 5
The wire 59 is wound at 7 and the multi-sheet feeding table 50 is raised.

When feeding a large number of sheets, the dial 42 is at an upper position where it can be operated as shown in FIG. 6 (a). Therefore, if the upper and lower fence stands 30 and 24 and the upper tray 51 of the multi-sheet feed stand 50 are laterally adjusted by dial operation, the printing position on the printing paper 68 can be finely adjusted.

When it is desired to feed the cassette in the middle of printing a large number of sheets, the cassette feeding mode is selected, and as shown in FIG.
As shown in FIG. 3, the paper feeding unit 10 is lowered, and the cassette base 12 is positioned immediately below the paper feeding mechanism 3. Even at this time, the paper feeding mechanism 3 does not interfere with the cassette base 12 and the cutout portion 1
You can go through 4. And cassette stand 12
The cassette K containing the printing paper 69 is set on the upper side of FIG.
As shown in (b), the paper feed unit 10 is positioned so that the pickup roller of the paper feed mechanism 3 contacts the upper surface of the print paper 69 in the cassette K with a predetermined pressure, and the paper feed mechanism 3 prints the print paper 69. Send out.

When the cassette is fed, the dial 42 is hidden behind the cover 65 as shown in FIG. 6B, and therefore cannot be operated even if the lid 66 is opened. That is, there is no risk of accidentally moving the position of the multi-sheet feeding table 50 that has already been adjusted when feeding the cassette by interruption.

In the above embodiment of the present invention, the paper feed mechanism 3 is shown as one component of the printer 2. However, the paper feed mechanism 3 may be provided on the paper feed device 1 side. May be.

In the above-described embodiment of the present invention, the first paper feed tray is used as a cassette paper feed tray, and the second paper feed tray is used as a multiple paper feed tray. All of the paper feed trays may be used as cassette paper feed trays, or a paper position regulating fence that can be adjusted in position according to the paper size may be provided on the first paper feed tray. Instead of using a paper cassette, a recording sheet may be directly placed on a table for feeding a large number of sheets.

Further, in the above-described embodiment of the present invention, one cassette sheet feeding table and one multi-sheet sheet feeding table are provided.
For convenience, two paper feed trays are provided, but three or more paper feed trays may be provided. However, in this case, all of the other paper feed trays (first paper feed tray) except the lowermost (second paper feed tray) paper feed tray are connected to the cassette tray in the embodiment of the present invention. A notch portion similar to the notch portion 14 of 12 is formed.

[0042]

According to the paper feeding apparatus of the present invention, a plurality of paper feeding trays can be moved up and down to selectively position a desired paper feeding tray at a paper feedable position for one paper feeding mechanism. With this configuration, the sheets set on the plurality of sheet feeding trays can be selectively taken out by one sheet feeding mechanism and fed to the image recording unit of the image forming apparatus.

Further, since the sheets set in the plurality of sheet feeding trays are selectively fed to the image recording section by one sheet feeding mechanism, the image can be fed from the sheet feeding mechanism no matter which sheet is fed. Since the paper feed path to the recording unit does not change and the paper feed timing is constant, there is no need for a device or adjustment for making the paper feed timing to the image recording unit constant, especially due to a slight difference in the paper feed timing. In the stencil printing machine in which the top and bottom are displaced, there is an excellent effect in improving the printing quality.

Further, since the sheets set in the plurality of sheet feeding trays are selectively fed to the image recording section by one sheet feeding mechanism, the constitution of the sheet feeding path is simple and the maintenance and inspection thereof are easy. At the same time, since the space required for the paper feed path is small, there is an effect that the entire apparatus can be downsized.

In particular, according to the present invention, the cassette is placed on the first paper feed tray on the paper feed unit that moves up and down with respect to the paper feed mechanism, and the recording is placed on the second paper feed tray. Since the pair of fences that regulate the positions of both side edges of the paper are provided in the paper feeding unit, a sufficient installation space for the cassette is secured, and the fence is placed on the paper feeding table according to the desired paper size. The cassette can be arbitrarily changed, and the sheet size of a large number of recording sheets can be arbitrarily changed.

[Brief description of drawings]

FIG. 1 is a perspective view of a sheet feeding device and a printing device according to an embodiment.

FIG. 2 is a perspective view showing a main drive mechanism and the like of the sheet feeding device in one embodiment.

FIG. 3 is a front view showing the structure and the like of the main part of the paper feeding device in one embodiment.

FIG. 4 is a perspective view showing a drive source and the like of the sheet feeding device in one embodiment.

FIG. 5 is a perspective view showing a fence adjusting mechanism and the like in the sheet feeding device according to the embodiment.

FIG. 6 is a perspective view showing movement of a dial in the sheet feeding device according to the embodiment.

FIG. 7A is a schematic diagram showing a state in which a large number of sheets are fed by the sheet feeding device of the embodiment, and FIG. 7B is a diagram when cassette feeding is performed by the sheet feeding device of the embodiment. It is a schematic diagram which shows the state of.

FIG. 8A is a perspective view showing a configuration example of a conventional image forming apparatus provided with a paper feeding device, and FIG. 8B is a perspective view of the paper feeding device with a frame pulled out.

[Explanation of symbols]

 1 Paper Feeding Device 2 Printing Device 3 Paper Feeding Mechanism 10 Paper Feeding Unit 12 Cassette Table as First Paper Feeding Table 14 Notch 24 Lower Fence Table 30 Upper Fence Table 50 Multiple Sheet Supply as Second Paper Feeding Table Paper board 61 Fence 68,69 Printing paper K cassette

Claims (2)

[Claims] 1. A set of paper feeding mechanism for picking up the stacked recording sheets one by one at a fixed position toward an image recording unit, and a paper feeding unit movable up and down with respect to the paper feeding mechanism. A first paper feed table provided at an upper portion of the paper feed unit, the first paper feed tray having a cutout portion that can pass through the paper feed mechanism while avoiding the paper feed unit, and the first paper feed unit. A second paper feed table that is vertically movable in the paper feed unit below the table, and both side edges of the recording paper that is provided in the paper feed unit and placed on the second paper feed table. And a pair of fences that regulate the position of the sheet. 2. A set of sheet feeding mechanism for picking up the stacked recording sheets one by one at a fixed position and feeding them toward an image recording section, a vertically movable sheet feeding unit, and an upper portion of the sheet feeding unit. A cassette for storing recording paper, which has a notch portion through which the recording mechanism can be passed when moving up and down of the paper feeding mechanism together with the paper feeding unit A paper feed table, a second paper feed table that is vertically movable in the paper feed unit below the first paper feed table, and has recording paper stacked on the upper surface, and the second paper feed table. Paper feeding of an image forming apparatus including a pair of fences provided in the paper feeding unit so as to be movable and adjustable according to the size of the recording paper placed on the paper tray, and having a pair of fences for regulating the positions of both side edges of the recording paper. apparatus.