JP4784204B2 - Paper feeding cassette and image forming apparatus - Google Patents

Description

  The present invention relates to a paper feed cassette and an image forming apparatus having the paper feed cassette.

In general, image forming apparatuses such as copying machines, printers, and facsimiles are known that include a manual paper feed unit and a duplex printing unit. In this type of image forming apparatus, there is a tendency for the apparatus to increase in size because a sheet conveyance path and a sheet guide member for conveying sheets from a manual sheet feeding unit and a duplex printing unit are provided. In view of this, it is known that the entire size of the apparatus is reduced by making the end of the paper feed cassette curved (for example, Patent Document 1).

JP-A-5-201553

  However, although the conventional technique is effective in reducing the projection area of the paper feed cassette, that is, in the projection plane direction of the apparatus, the apparatus in the height direction has not been sufficiently reduced.

  An object of the present invention is to provide a paper feed cassette and an image forming apparatus that solve the above-described conventional problems and realize a reduction in the height of the apparatus main body.

In order to achieve the above object, the first feature of the present invention is:
A sheet storage unit on which a large number of sheets are stacked; and at least one of a double-sided printing sheet supply unit and a manual sheet supply unit provided on the sheet storage unit, having a concave arcuate shape, on the image forming apparatus main body side A guide for guiding the paper supplied from the paper storage unit to the registration roll in a direction different from the supply direction of the paper supplied from the paper storage unit to the registration roll. When the sheet is mounted on the image forming apparatus main body, it moves to form a part of the sheet conveyance path with the opposing portion on the image forming apparatus main body side, and when the paper feeding cassette is pulled out from the image forming apparatus main body. A paper feed cassette that is retracted so as not to interfere with the image forming apparatus. It is in.

The second feature of the present invention is that the image forming apparatus main body, a registration roll provided in the image forming apparatus main body, a paper feed cassette provided in a freely retractable manner in the image forming apparatus main body, A sheet provided in the sheet feeding cassette and having a concave arc shape, and is supplied to the registration roll from at least one of a duplex printing sheet feeding unit and a manual sheet feeding unit disposed in the image forming apparatus main body. And a guide for guiding the sheet in a direction different from a direction in which the sheet to be supplied from the sheet cassette to the registration roll is mounted, and the guide is mounted when the sheet cassette is mounted on the image forming apparatus main body. To form a part of a sheet conveyance path with the opposing portion on the image forming apparatus main body side, and the image formation when the paper feeding cassette is pulled out from the image forming apparatus main body. In an image forming apparatus to save so as not to interfere with the location.

  Preferably, the guide is movably supported by the paper feed cassette, and is accommodated in the paper feed cassette when the paper feed cassette is pulled out from the image forming apparatus main body.

  Preferably, jamming is performed by pulling out the paper feed cassette from the image forming apparatus main body.

  Preferably, a detection sensor for detecting the presence or absence of the paper feed cassette is further provided, and the detection of the jam processing is performed by the detection sensor.

  According to the present invention, since the guide constituting at least one conveyance path of the duplex printing sheet feeding unit and the manual sheet feeding unit is formed in the sheet feeding cassette, the apparatus main body can be miniaturized in the height direction. it can.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an outline of an image forming apparatus 10 according to the first embodiment of the present invention. The image forming apparatus 10 includes an image forming apparatus main body 12, an image forming unit 14 is mounted in the image forming apparatus main body 12, and a discharge unit 16 is provided on the upper portion of the image forming apparatus main body 12. A paper feed unit 18 is disposed below the image forming apparatus main body 12. Further, the image forming apparatus main body 12 is provided with a transport path 17 for transporting paper. The transport path 17 includes a first transport path 25, a second transport path (transport path 50 for double-sided printing), and a second transport path, which will be described later. 3 transport paths (manual transport path 57).

  The paper feed unit 18 has a paper feed cassette 20, paper feed rolls 22 a and 22 b, and a first transport path 25 that are provided with paper as a transfer material stored therein and that can be pulled out to the image forming apparatus main body 12. The paper stored in the paper feed cassette 20 is conveyed to the registration roll 24 by the rotation of the paper feed rolls 22a and 22b.

  The registration roll 24 is provided in the first conveyance path 25, and an image carrier 28 and a transfer device 36 of a process cartridge (development cartridge) 46, which will be described later, on the downstream side of the first conveyance path 25. And a fixing device 40 is further provided on the downstream side thereof.

  Accordingly, the sheet fed from the sheet feeding cassette 20 of the sheet feeding unit 18 by the sheet feeding rolls 22a and 22b is temporarily stopped by the registration roll 24, and is timed between the image carrier 28 and the transfer device 36. The developer image is transferred therethrough, and the transferred developer image is fixed by the fixing device 40 and discharged to the discharge portion 16 by the discharge roll 26. In other words, the sheet fed from the sheet feeding unit 18 is transported along the first transport path 25 formed from the sheet feeding rolls 22 a and 22 b to the discharge roll 26.

  A duplex unit 48 is provided on the side surface (left side in FIG. 1) of the image forming apparatus main body 12, and a duplex printing paper feed portion 49 is provided in the duplex unit 48. The double-sided printing paper feeding section 49 is connected to the second conveyance path (double-sided printing conveyance path 50) returning from the bifurcated portion in front of the discharge roll 26 to the registration roll 24 and the double-sided printing conveyance path 50. It has the conveyance rolls 52a and 52b arrange | positioned.

  In the case of duplex printing, the paper sent out from the paper feed cassette 20 is returned to the duplex unit 48. That is, a switching claw (not shown) is provided at the front portion of the discharge roll 26, and in the case of duplex printing, the switching claw (not shown) is provided on the duplex printing paper conveyance path 50. Is switched to the open side, and the discharge roll 26 is reversed when the discharge roll 26 is in front of the trailing edge of the sheet, and the sheet is guided to the sheet feeding unit 49 for duplex printing. The sheet fed from the duplex printing sheet feeding unit 49 is temporarily stopped by the registration roll 24, merges with the first conveyance path 25 described above, and is discharged to the discharge unit 16.

  A manual feed unit 54 is disposed on the side surface (left side surface in FIG. 1) of the image forming apparatus main body 12. The manual feed unit 54 includes a manual feed tray 56 for storing paper and a manual paper feed unit 55. The manual paper feed unit 55 includes a third paper feed path (manual feed path 57) and a manual paper feed roll 58 formed from the manual feed tray 56 to the registration roll 24. The paper stored in the manual feed tray 56 is fed into the manual feed path 57 (manual feed) by the rotation of the manual feed roll 58. The paper fed out by the manual paper feed unit 55 is temporarily stopped by the registration roll 24, merges with the first conveyance path 25 described above, and is discharged to the discharge unit 16.

  The image forming means 14 is of an electrophotographic type, and includes an image carrier 28 made of a photoconductor, a charging device 30 made of, for example, a charging roll for uniformly charging the image carrier 28, and charging by the charging device 30. An optical writing device 32 that writes a latent image on the image carrier 28 by light, a developing device 34 that visualizes a latent image of the image carrier 28 formed by the optical writing device 32, and a developing device 34 For example, a transfer device 36 that transfers the developer image onto the paper, a cleaning device 38 that cleans the developer remaining on the image carrier 28, and a developer image on the paper transferred by the transfer device 36 is fixed on the paper. The fixing device 40 includes a pressure roll and a heating roll. The optical writing device 32 is composed of, for example, a scanning laser exposure device, and traverses the process cartridge 46 to form a latent image on the image carrier 28. The cleaning device 38 includes a cleaning blade 42 that comes into contact with the image carrier 28 and a developer recovery unit 44 that stores the developer scraped off by the cleaning blade 42. The optical writing device 32 may use an LED or a surface emitting laser as another embodiment.

  In the process cartridge 46, the image carrier 28, the charging device 30, the developing device 34, and the cleaning device 38 are integrated, and these can be replaced as a unit.

The paper feed cassette 20 described above is provided with a paper transport path 60. When a plurality of paper feed cassettes are arranged in multiple stages by this paper transport path 60, paper fed from other paper feed cassettes arranged on the lower side is transported.
The paper feed cassette 20 is formed with a first guide portion 62 and a second guide portion 64 which will be described later.

FIG. 2 shows the entire sheet cassette 20.
As shown in FIG. 2, the paper feed cassette 20 is provided with a paper storage portion 66, a first guide portion 62, and a second guide portion 64 as a guide.
The sheet accommodating portion 66 is composed of a bottom surface portion 68 and a frame portion 70 erected in the vertical direction from the bottom plate surface portion 68, and a large number of sheets are stacked on the sheet accommodating portion 66. The first guide portion 62 is formed on the inner wall surface of the front portion in the paper feeding direction of the paper storage portion 66 and guides the paper supplied from the paper storage portion 66. The second guide part 64 is formed integrally with the frame part 70 of the paper feed cassette 20 on the upper surface of the front part of the paper feed cassette 20 (by the paper feed unit 18) in the paper feed direction. A plurality of concave arc-shaped guide ribs 72 are formed in the second guide portion 64 in a direction parallel to the paper feeding direction.

As shown in FIG. 3, the second guide unit 64 supplies the duplex printing when the paper feed cassette 20 is attached to the image forming apparatus main body 12 (the paper feed cassette 20 is moved in the direction of arrow B in FIG. 3). At least one of the paper path 49 and the manual paper feed section 55 is configured. In this example, the second guide unit 64 constitutes a part of the duplex printing conveyance path 50 of the duplex printing sheet feeding unit 49 and the manual conveyance path 57 of the manual sheet feeding unit 55.
Accordingly, the second guide portion 64 is formed to constitute at least a part of the conveyance path 17 that supplies the image forming apparatus main body 12 from at least one of the duplex printing paper feed portion 49 and the manual paper feed portion 55. A sheet to be conveyed is guided when performing duplex printing and manual sheet feeding.

  Further, the image forming apparatus main body 12 is provided with a cassette sensor 74 as a detection sensor for detecting whether or not the paper feeding cassette 20 is present, that is, whether or not the paper feeding cassette 20 is attached to the image forming apparatus 12. .

  In this way, by forming the second guide portion 64 constituting at least one of the double-sided printing paper feeding portion 49 and the manual paper feeding portion 55 in the paper feeding cassette 20, a new guide member is formed as an image. It is not necessary to provide the device main body 12, and the height direction of the device main body can be reduced. That is, the image forming apparatus 10 according to the present invention can shorten the height of the guide member 86 as compared with the image forming apparatus having the guide member 86 shown in FIG. Specifically, when the length A shown in FIG. 1 is compared with the length A ′ shown in FIG. 6, the length A (shown in FIG. 1) is shorter.

  Further, by forming the second guide portion 64 in the paper feed cassette 20, the double-sided printing guide member and the manual paper feed guide member can be removed, and the number of parts and the cost can be reduced. .

When a jam (JAM) occurs during double-sided printing or manual sheet feeding, the jam processing can be performed by pulling out the sheet feeding cassette 20 from the image forming apparatus main body 12. That is, by pulling out the paper feed cassette 20 from the image forming apparatus main body 12 (moving the paper feed cassette 20 in the direction of arrow C in FIG. 3), a part of the transport path 17 appears. Can be removed. Thereby, the cover part and cover opening-and-closing mechanism part which were provided for the conventional jam processing can be removed.
Further, by detecting the jam processing by the cassette sensor 74 described above, it is not necessary to provide a conventional jam processing detection sensor (a cover opening / closing sensor for detecting opening / closing of the cover portion provided for the jam processing). That is, the sensor for detecting the jam processing is also used as the sensor for detecting the presence or absence of the paper feed cassette, thereby reducing the cost.

4 and 5 show a second embodiment of the second guide portion 64. Compared to the first embodiment described above, in the first embodiment, the second guide portion 64 is formed integrally with the paper feed cassette 20, but in the second embodiment, The second guide portion 64 is provided as a separate member from the paper feed cassette 20.
In addition, about the same part as 1st Embodiment, the same code | symbol is attached | subjected to FIG.4 and FIG.5, and the description is abbreviate | omitted.

  As shown in FIG. 4, a notch 76 is formed on the upper surface of the paper feed cassette 20 (by the paper feed unit 18) in the paper feed direction. A rotary shaft 78 is rotatably supported by the paper feed cassette 20 at an upper portion of the notch 76 in front of the paper feed direction (by the paper feed unit 18). In the second guide portion 64, one end portion of the second guide portion 64 is fixed to the rotation shaft 78, and the other open end portion rotates about the rotation shaft 78 ( It can be rotated in the directions of arrows D and E in FIG. That is, the second guide portion 64 is rotatably supported by the paper feed cassette 20. When the second guide portion 64 is in a position (a position indicated by a solid line in FIG. 4) in contact with the notch portion 76, the second guide portion 64 is accommodated in the notch portion 76. . In addition, columnar projecting pins 80 and 80 are formed on the left and right side portions of the second guide portion 64 in the sheet feeding direction so as to project from both side portions.

The image forming apparatus main body 12 is provided with slide portions 82 and 82. The slide portions 82 and 82 are disposed at positions where the projecting pins 80 and 80 of the above-described second guide portion 64 abut when the paper feed cassette 20 is mounted on the image forming apparatus main body 12. The slide portions 82, 82 are provided with inclined surfaces 84, 84. When the paper feed cassette 20 is mounted on the image forming apparatus main body 12, that is, the paper feed cassette 20 is moved in the direction of arrow F (see FIGS. 4 and 5). The projecting pins 80, 80 move upward while sliding on the inclined surfaces 84, 84.
Therefore, as shown in FIG. 5, when the paper feed cassette 20 is mounted on the image forming apparatus main body 12, the second guide 64 rotates upward (in the direction of arrow E in FIG. 5) about the rotation shaft 78. To do. As a result, the second guide section 64 constitutes a conveyance path for the duplex printing sheet feeding section 49 and the manual sheet feeding section 55, that is, a part of the duplex printing conveyance path 50 and the manual conveyance path 57. Yes.

As described above, by mounting the paper feed cassette 20 on the image forming apparatus main body 12, the second guide unit 64 can guide the paper conveyed from the reversing path 50 and the manual feed path 57 to the registration roll 24. it can. Further, by pulling out the paper feed cassette 20 from the image forming apparatus main body 12, the second guide portion 64 can be accommodated in the paper feed cassette 20 (in the notch 76). Therefore, the conveyed paper is stable and jam is unlikely to occur, and the height of the image forming apparatus body 12 can be suppressed without interfering with the apparatus body side when the sheet feeding cassette is pulled out.
In the above-described example, the guide unit 64 is described as being rotatably supported with respect to the paper feed cassette 20. However, the guide unit 64 is fed in such a manner that the guide unit 64 slides with respect to the paper feed cassette 20. The present invention is not limited to these configurations as long as it can be retracted into the paper cassette 20 (in the notch 76). In addition, the guide unit 64 may be retracted until it is completely buried in the paper feed cassette 20 (in the notch 76), and a part of the guide unit 64 is in the paper feed cassette 20 (in the notch 76). It may be retracted and accommodated.

1 is a cross-sectional view of an image forming apparatus according to a first embodiment of the present invention. It is a perspective view of the paper feed cassette in the 1st embodiment of the present invention. FIG. 5 is a cross-sectional view illustrating the vicinity of a second guide portion of the paper feed cassette according to the first embodiment of the present invention. FIG. 6 is a perspective view showing a paper feeding cassette according to a second embodiment of the present invention and showing a state in which the paper feeding cassette is attached to the image forming apparatus main body. It is sectional drawing which showed the 2nd guide part periphery of the paper feed cassette in the 2nd Embodiment of this invention. It is sectional drawing of the image forming apparatus of a structure which has a guide member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Image forming apparatus main body 17 Conveyance path 20 Paper feed cassette 49 Double-sided printing paper feed section 50 Double-sided printing conveyance path 55 Manual paper feed section 57 Manual feed path 62 First guide section 64 Second guide section 74 Cassette sensor

Claims (5)

A paper container for loading a large number of papers;
Wherein provided in the sheet accommodating section has an arcuate shape of the concave, a paper sheet to be fed from at least one of the duplex printing paper feed unit of the image forming apparatus body and a manual sheet feeder to the registration roller, the sheet A guide for guiding in a direction different from the supply direction of the paper supplied from the storage unit to the registration roll ;
Have
The guide is
When the paper feeding cassette is mounted on the image forming apparatus main body, it moves to form a part of the paper transport path with the opposing portion on the image forming apparatus main body side,
A paper feeding cassette which is retracted so as not to interfere with the image forming apparatus when the paper feeding cassette is pulled out from the image forming apparatus main body. An image forming apparatus main body;
A resist roll provided in the image forming apparatus main body;
A paper feed cassette provided in the image forming apparatus main body so as to be freely drawn out;
Provided in the paper feed cassette, has a concave arcuate shape, and is supplied to the registration roll from at least one of a double-sided printing paper feed unit and a manual paper feed unit provided in the image forming apparatus main body. A guide for guiding the paper in a direction different from the supply direction of the paper supplied from the paper feed cassette to the registration roll ;
Have
The guide is
When the paper feed cassette is mounted on the image forming apparatus main body, it moves to form a part of a paper transport path with the facing portion on the image forming apparatus main body side,
An image forming apparatus, wherein the paper feeding cassette is retracted so as not to interfere with the image forming apparatus when the paper feeding cassette is pulled out from the main body of the image forming apparatus.   3. The guide according to claim 2, wherein the guide is movably supported by the paper feed cassette and is accommodated in the paper feed cassette when the paper feed cassette is pulled out from the image forming apparatus main body. Image forming apparatus.   The image forming apparatus according to claim 2, wherein jamming is performed by pulling out the paper feed cassette from the main body of the image forming apparatus. A detection sensor for detecting the presence or absence of the paper cassette;
The image forming apparatus according to claim 4, wherein the detection of the jam processing is performed by the detection sensor.

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