JP6545313B2 - Sheet feeding apparatus and image forming apparatus - Google Patents

Description

The present invention is related to an image forming apparatus including a sheet feeding apparatus and which for feeding the sheet.

  Nowadays, in image forming apparatuses such as copying machines, printers, and facsimiles, an apparatus in which a sheet stored in a sheet storage unit is fed to an image forming unit to form an image is widely used. As such a sheet storage means, there is one provided with a plate-like sheet stacking means for stacking sheets so as to be movable up and down.

  Then, when the sheet is to be replenished, the sheet stacking means is lowered, and when the sheet is fed, the sheet stacking means is raised and the upper surface of the stacked sheets is moved to a position where it can be fed by the upper pickup roller. Let Further, the sheet storage unit is provided so as to be able to be pulled out from the apparatus main body, and when the sheet is stored, the sheet storage unit is pulled out and then the sheet is set on the sheet stacking unit from above.

  The sheet storage unit includes a rear end control unit that controls the position of the upstream end (hereinafter referred to as a rear end) of the sheets stacked on the sheet stacking unit so as to store sheets of different sizes. It is provided to be movable along the sheet feeding direction. Further, in the sheet storage means, a side end regulating means for regulating the side end position in a direction (hereinafter referred to as the width direction) orthogonal to the sheet feeding direction of the sheet is provided movably in the width direction. Then, the position of the sheet is restricted to a predetermined position by restricting the side end of the sheet by the side end restricting means and restricting the rear end of the sheet by the rear end restricting means (see Patent Document 1). .

  FIG. 6 is a view showing a configuration of a sheet feeding cassette 50 which is a sheet storage unit provided with such a regulation unit. The sheet cassette 50 can selectively accommodate A3 size sheet S1 and 11 × 17 inch size sheet S2. The sheet feeding cassette 50 includes a pair of side end restricting plates 51 and 52 movable in the width direction that restricts the position in the width direction of the two sizes of sheets S1 and S2 to be stored, and the rear end of the sheets S1 and S2. The rear end restricting plate 63 is movable in the sheet feeding direction to restrict the sheet.

  Here, when the sheet feeding cassette 50 is inserted into the image forming apparatus main body, for example, in a full state, an impact is applied to the sheet feeding cassette 50, and the side end regulating plates 51 and 52 are bent by this impact, and the sheet S1 is accompanied accordingly. , S2 may rotate with the side end regulating plates 51, 52 as a fulcrum. Therefore, the sheet cassette 50 corresponds to the rear end side of the side edge of the A3 size sheet S1 and the 11 × 17 inch size sheet S2 in order to prevent the rotation of the sheets S1 and S2 due to the impact upon insertion. At positions, ribs 53 and 54 for preventing sheet rotation are provided.

Patent No. 3359174 gazette

  By the way, in the conventional sheet storage means, the ribs 53 and 54 for preventing sheet rotation are the side edges of the sheet S1 having the largest sheet width or the sheet S2 having the largest sheet length among the sheets that can be accommodated as described above. Is disposed at a position corresponding to the rear end side of. For this reason, when a sheet having a size smaller than the sheets S1 and S2 is stored in the sheet feeding cassette 50, the sheet strikes the ribs 53 and 54 when an impact is applied to the sheet feeding cassette 50 at the time of insertion. It will rotate to the end. Alternatively, even after the collision, the rotatable ribs 53 and 54 may be rotated while being rotated. As a result, the sheet is displaced inside the sheet feeding cassette 50, and the image on the sheet is offset by the offset amount, or the sheet is skewed and the image is formed obliquely on the sheet.

Therefore, the present invention has been made in view of such a current situation, and an object of the present invention is to provide a sheet feeding apparatus and an image forming apparatus capable of preventing the rotation of a sheet due to an impact at the time of inserting a sheet feeding cassette. It is said that.

A sheet feeding apparatus according to an aspect of the present invention is provided detachably with respect to an apparatus main body, and is movable in a width direction orthogonal to a sheet feeding direction with a sheet feeding cassette for storing sheets to be fed. A side end regulating means for regulating the side end of the sheet stored in the sheet feeding cassette, and a predetermined sheet main body of the sheet feeding cassette upstream of the side end regulating means in the sheet feeding direction In order to regulate the position of the auxiliary member detachably provided at the mounting position and the upstream end of the sheet stored in the sheet feeding cassette in the sheet feeding direction, in the sheet feeding direction independently of the auxiliary member along movably provided, and the sheet feeding direction and a trailing edge regulating member movable from an upstream auxiliary member mounted on said cassette body, the auxiliary member to the predetermined attachment position When a mounting operation is performed in which the sheet of the first size is stored in the sheet feeding cassette that is not attached and the sheet feeding cassette is attached to the apparatus body, the cassette body contacts the side edge of the sheet of the first size Rotation of the sheet of the first size can be suppressed, and the length in the width direction of the sheet feeding cassette having the auxiliary member mounted at the predetermined mounting position is greater than that of the first size When a short second size sheet is stored and the mounting operation of the sheet feeding cassette is performed, the auxiliary member contacts the side edge of the second size sheet to suppress the rotation of the second size sheet. It is possible that the paper feed cassette includes a housing portion for housing the auxiliary member when the auxiliary member is not used, and the side end regulating means is a first side end. Control member and front And a second side edge regulating member disposed downstream from said first side edge regulating member in the insertion direction of the paper feed cassette to the apparatus main body, wherein the accommodating portion, the insertion of the paper feed cassette in the direction, is provided at a position closer to the first an outer storage area size of the sheet, and wherein the than the second side edge regulating member first side edge regulating member in the sheet feeding cassette It is characterized by

According to the present invention , the rotation of the sheet can be prevented.

FIG. 1 is a view showing a schematic configuration of a full-color laser beam printer which is an example of an image forming apparatus according to an embodiment of the present invention. FIG. 6 is a view for explaining the configuration of a mounting portion of the full-color laser beam printer and a sheet feeding cassette which is detachably mounted to the mounting portion. FIG. 6 is a view for explaining the configuration of the front side regulating member provided in the sheet feeding cassette. The figure explaining the operation | movement which mounts | wears the said front side side control member with an auxiliary | assistant side control member. FIG. 6 is a view showing a state in which sheets of different sizes are stored in the sheet feeding cassette. FIG. 6 is a view showing the configuration of a conventional sheet feed cassette.

  Hereinafter, an example of the sheet feeding apparatus of the present invention will be described in detail using the drawings. FIG. 1 is a view showing a schematic configuration of a full-color laser beam printer as an example of an image forming apparatus according to an embodiment of the present invention. In FIG. 1, 1 is a full-color laser beam printer (hereinafter referred to as a printer), 1A is a printer main body which is an image forming apparatus main body, 1B is an image forming section for forming an image on a sheet, and 20 is a fixing section. An image reading apparatus 2 is an upper apparatus installed substantially horizontally above the printer main body 1A, and a discharge space P is formed between the image reading apparatus 2 and the printer main body 1A. Reference numeral 30 denotes a sheet feeding device provided below the printer main body 1A, and reference numeral 15 denotes a toner cartridge.

  Image information read by the image reader 2 or image information input from an external device such as a personal computer (not shown) is subjected to image processing, converted into an electric signal, and transmitted to the laser scanner 10 of the image forming unit 1B. . Then, in the image forming unit 1B, the surface of the photosensitive drum 12 of each process cartridge 11 is scanned with laser light corresponding to the image information of yellow, magenta, cyan and black components emitted from the laser scanner 10. As a result, the surface of the photosensitive drum 12 whose surface is uniformly charged to a predetermined polarity and potential is sequentially exposed by the charger 13, and yellow, magenta, and cyan are respectively formed on the photosensitive drums of the respective process cartridges 11. And black electrostatic latent images are sequentially formed.

  Thereafter, the electrostatic latent image is developed and visualized by the developing device 14 with yellow, magenta, cyan and black toners. Then, with the primary transfer bias applied to the primary transfer roller 19, the color toner images on the respective photosensitive drums are sequentially superimposed on the intermediate transfer belt 16 and transferred. Thus, a toner image is formed on the intermediate transfer belt 16.

  On the other hand, the sheet S fed from the sheet feeding device 30 passes through the registration roller pair 40 and is fed to a secondary transfer portion constituted by the drive roller 16 a and the secondary transfer roller 17. At the secondary transfer portion, the toner images formed by the image forming portion 1B are collectively transferred onto the sheet S. Next, the sheet S on which the toner image has been transferred in this manner is conveyed to the fixing unit 20, and is subjected to heat and pressure in the fixing unit 20, and is fixed on the sheet S as a color image.

  Thereafter, the sheet S on which the image is fixed is discharged to the discharge space P by the discharge roller pair 25a and 25b, and is stacked on the stacking unit 23 which protrudes to the bottom of the discharge space P. When an image is formed on both sides of the sheet S, after the image is fixed, the sheet S is conveyed to the re-conveying path R by the pair of reversible rollers 22 provided in the both-side reversing unit 1D. Thereafter, the sheet is conveyed again to the image forming unit 1B.

  Here, the sheet feeding cassette 60, which is a sheet storage unit, is detachably mounted to a mounting portion 1E shown in FIG. 2 formed in the lower part of the printer main body 1A. As shown in FIG. 2, in the sheet feeding cassette 60, the back side side regulating plate 61 which regulates one side in the depth direction (width direction) orthogonal to the sheet feeding direction of the sheet S, that is, the downstream side in the depth direction. Is provided to be movable in the depth direction. Further, the paper feed cassette 60 is provided so as to be movable in the depth direction, and is provided so as to be opposed to the back side restriction plate 61 and restricts the position of the upstream side of the sheet S in the depth direction. There is. Incidentally, the back side side regulating plate 61 and the front side side regulating plate 62 constituting the pair of side end regulating means 61A are the side end positions of the sheet in the depth direction upstream side and the depth direction downstream side by the interlock mechanism not shown. Move together to regulate.

  In the sheet feeding cassette 60, a rear end restricting plate 63 for restricting the position of the rear end which is the upstream end of the sheet S in the sheet feeding direction is provided movably along the sheet feeding direction. Further, the sheet feeding cassette 60 is provided with a middle plate (not shown) on which the sheets are stacked, and the sheets stacked on the middle plate are a back side side regulating plate 61, a front side side regulating plate 62, and the like. The position is regulated by the rear end regulating plate 63.

  A swing arm 64 having a swing pin 65 at its front end is swingably supported by a back side wall 60a of the cassette main body 60A of the paper feed cassette 60 with a shaft 64a as a fulcrum. Further, on the inner wall surface on the back side of the mounting portion 1E, a drawing-in unit 66, which is a drawing-in means for drawing the sheet feeding cassette 60 into the mounting portion 1E, is disposed. The retraction unit 66 includes a retraction unit base 69, and a retraction arm 68 provided with a retraction hook 67 at the tip and rotatably supported around a fulcrum 70 on the retraction unit base 69.

  The pull-in hook 67 of the pull-in arm 68 is formed with a recess 91 for locking the swing pin 65 of the swing arm 64. Further, an arm pin 71 is provided between the pull-in hook 67 of the pull-in arm 68 and the fulcrum 70, and the arm pin 71 is a tension spring 73 whose one end is locked to a base pin 72 provided on the pull-in unit base 69. The other end of the is locked. The pull-in arm 68 is urged by the tension spring 73 to pivot about the fulcrum 70.

  When pulling out the sheet feeding cassette 60, while the recess 91 locks the swing pin 65, the pull-in arm 68 resists the tension spring 73 from the position shown in FIG. Rotate counterclockwise. Thereafter, when the paper feed cassette 60 is further pulled out, the pull-in arm 68 is pivoted to the standby position where the locking of the swing pin 65 by the recess 91 is released. When the pull-in arm 68 is pivoted by a predetermined amount before pivoting to the standby position, the pull-in arm 68 is applied with a force to pivot counterclockwise by the tension spring 73. By this force, the pull-in arm 68 moves to the standby position and then abuts on a stopper (not shown) and stops.

  When in the standby position, the pull-in arm 68 is at a position where the swing pin 65 of the swing arm 64 enters the recess 91 of the pull-in hook 67 when the sheet feeding cassette 60 is attached to the printer body 1A. Therefore, when the sheet feeding cassette 60 is inserted into the mounting portion 1E, the swinging pin 65 enters the recess 91 of the pull-in hook 67. Thereafter, when the paper feed cassette 60 is further pushed in, the pull-in arm 68 is pushed to the rear side via the swing pin 65 and the pull-in hook 67.

  As a result, the pull-in arm 68 pivots clockwise about the fulcrum 70 while resisting the tension spring 73, and when it is pivoted to a predetermined position, the pull-in arm 68 is biased by the tension spring 73. It rotates in the clockwise direction. Then, the recess 91 of the pull-in hook 67 is engaged with the swing pin 65 while the pull-in arm 68 is thus rotated clockwise. As a result, when the pull-in arm 68 is rotated by the tension spring 73, the sheet feeding cassette 60 is mounted while receiving the biasing force in the depth direction by the pull-up spring 73 via the pull-in arm 68.

  As shown in FIG. 2, when the sheet feeding cassette 60 is attached to one end (right end) orthogonal to the depth direction upstream of the cassette body 60A in the depth direction, positioning of the sheet feeding cassette 60 in the depth direction is performed. A positioning unit 74 is provided. Then, when the sheet feeding cassette 60 is attached, the positioning section 74 positions the sheet feeding cassette 60 in the depth direction. Further, after the sheet feeding cassette 60 is mounted, the middle plate rotatably provided on the cassette main body 60A in the vertical direction is lifted, and the sheet S on the middle plate abuts on the pickup roller 75.

  In the present embodiment, as shown in FIG. 2, the back side side regulating member 80 is upstream of the back side wall 60a in the sheet feeding direction, and the sheet feeding direction upstream of the front side wall 60b of the cassette body 60A. A front side regulation member 81 is provided on the side. The distance between the back side control member 80 and the front side control member 81 constituting the pair of upstream end control means 80A in the width direction is the maximum sheet width of the sheets that can be accommodated in the paper feed cassette 60. It is set to.

  In the present embodiment, since the maximum sheet size is LGL, the distance between the back side control member 80 and the front side control member 81 in the width direction is set to the LGL width, and FIG. The state when S1 is accommodated is shown. Then, the positional deviation of the sheet S1 in the sheet feeding cassette 60 by the back side control plate 61, the front side control plate 62, the rear end control plate 63, the back side control member 80, and the front side control member 81. To prevent.

  Here, the front side side regulating member 81 is a position in the width direction of a sheet of a predetermined size (sheet of LGL size) having the largest sheet width among the sheets that can be accommodated in the sheet feeding cassette 60 as shown in FIG. Control section (control surface) 81a that controls the In addition, since the back side side regulation member 80 also has the same structure, only the front side side regulation member 81 will be described below.

  Further, the near side side regulating member 81 is provided with a mounting space 81c for selectively mounting the auxiliary side regulating member 82, which is an auxiliary side edge regulating means, from the upper opening. Here, the auxiliary side regulating member 82 regulates the position in the width direction of the small size sheet smaller than the sheet of the maximum sheet width that can be accommodated in the sheet feeding cassette 60, and the side end of the small size sheet And a convex portion 82a in contact with the

  In addition, when the auxiliary side regulating member 82 is mounted at the center in the sheet feeding direction of the regulating portion 81a of the front side regulating member 81, the upper and lower portions allow the convex portion 82a to protrude from the front side regulating member 81 to the sheet side. A slit groove 81b which is an opening extending in the direction is formed. Thereby, as shown in FIG. 4A, when the auxiliary side regulating member 82 is inserted from the upper opening of the mounting space of the near side side regulating member 81, the auxiliary side regulating member as shown in FIG. 4B. The convex portion 82a of 82 projects from the front side regulating member 81 to the inside of the cassette main body. A slide groove (not shown) extending in the vertical direction is formed on the back side of the restricting portion 81a for guiding the attachment of the auxiliary side restricting member 82 to the attachment space 81c from above.

  Then, in the present embodiment, when the small-sized sheet is accommodated in the sheet feeding cassette 60, the auxiliary side regulating member 82 is attached to the back side regulating member 80 and the front side regulating member 81. Thereby, the side end position of the small size sheet stored in the sheet feeding cassette 60 can be regulated.

  As shown in FIGS. 3 and 4, the auxiliary member accommodating portion 83 is adjacent to the front side wall 60b of the cassette body 60A at a position near the front side restriction member 81 which does not hinder the loading of the sheet. Is provided. When the auxiliary side regulating member 82 is not used, that is, when the sheet having the maximum sheet width is accommodated in the sheet feeding cassette 60, the auxiliary side regulating member 82 is accommodated in the auxiliary member accommodating portion 83. This can prevent the auxiliary side regulating member 82 from being lost.

  Here, in the present embodiment, as shown in (b) of FIG. 5 described later, the regulation width by the auxiliary side regulation member 82 attached to the back side regulation member 80 and the front side regulation member 81 is the LGL width ( It is set to A4 width (210 mm) smaller than 215.9 mm). When a sheet having a size smaller than this is to be stored, for example, when the regulation width is set to the B5 width (182 mm), an auxiliary side regulation member in which the amount of protrusion from the slit groove 81b is set to the B5 width is prepared.

  Further, in the present embodiment, the positions of the back side side regulating member 80 and the front side side regulating member 81 in the sheet feeding direction can be regulated to the side edges of LTR (215.9 mm) and A4 (210 mm) sized sheets. It is set to. 5A shows a state in which the sheet S2 of LTR size is accommodated in the sheet feeding cassette 60. FIG. Thereby, when the sheet S2 of LTR size is stored, the rear end vicinity of the sheet S2 abuts on the restricting surface of the restricting portion 80a of the back side side restricting member 80 and the restricting portion 81a of the near side side restricting member 81, and the width of the sheet S2 The position of the direction is regulated.

  5B shows a state in which the sheet S3 of A4 size is accommodated in the sheet feeding cassette 60. FIG. As described above, when the A4 size sheet S3 is stored, the auxiliary side regulating member 82 is attached to the back side regulating member 80 and the front side regulating member 81, respectively. Thus, when the sheet S3 of A4 size is stored, the vicinity of the rear end of the sheet S3 abuts against the convex portion 82a which is the regulating surface of the auxiliary side regulating member 82, and the position of the sheet S3 in the width direction is regulated. In the case of storing LGL which is the maximum sheet size in the present embodiment, since the sheet width of LGL is the same as the sheet width of LTR, the auxiliary side regulating member 82 is removed as shown in FIG. To accommodate the sheet.

  As described above, in the case of storing a sheet whose length in the depth direction (width direction) is shorter than a sheet of a predetermined size, the auxiliary side regulating member 82 is configured as the back side side regulating member 80 and the front side side regulating member 81. It is attached to the seat to regulate the side edge position of the seat. Thus, it is possible to prevent the rotation of the sheet due to the impact when the sheet feeding cassette 60 is inserted. As a result, the sheet can be supplied to the image forming unit 1B in a state in which the sheet skewing and positional deviation are suppressed, and the image deviation with respect to the sheet can be suppressed.

  In the present embodiment, the auxiliary side regulating member 82 is configured to slide in and out in the sheet stacking direction. Therefore, even when the sheet is stored, even if the user touches the auxiliary side regulating member 82 or inserts the sheet feeding cassette 60 with a strong force, the auxiliary side regulating member 82 is the back side side regulating member 80 and the front side side regulating member It does not come off easily from 81. As a result, it is possible to reliably regulate the position of the sheet in the width direction by the auxiliary side regulating member 82.

DESCRIPTION OF SYMBOLS 1 full color laser beam printer 1A printer main body 1B image forming part 1E mounting part 60 sheet feeding cassette 60A cassette main body 60a rear side wall of cassette main body 60b front side of cassette main body Side wall 61: back side regulation plate 61A: side end regulation means 62: front side regulation plate 63: rear end regulation plate 80: back side regulation member 80A: upstream side regulation means 81: 81 A front side side regulating member, 81a: regulating portion, 81b: slit groove, 81c: mounting space, 82: auxiliary side regulating member, 82a: convex portion, 83: assisting member accommodating portion, S, S1, S2, S3: sheet

Claims (5)

A sheet feeding cassette which is detachably provided to the apparatus main body and stores the fed sheet;
A side end regulating means which is provided movably in a width direction orthogonal to the sheet feeding direction, and which can regulate the side end of the sheet stored in the sheet feeding cassette;
An auxiliary member detachably provided at a predetermined mounting position of the cassette main body of the sheet feeding cassette upstream of the side end regulating unit in the sheet feeding direction;
In order to regulate the position of the upstream end of the sheet stored in the sheet feeding cassette in the sheet feeding direction, the sheet feeding device is provided movably along the sheet feeding direction independently of the auxiliary member, and the sheet feeding A rear end restricting member movable upstream of the auxiliary member attached to the cassette body in a direction;
When a mounting operation is performed in which a sheet of a first size is stored in the sheet feeding cassette in which the auxiliary member is not attached at the predetermined attachment position and the sheet feeding cassette is attached to the apparatus main body, It is possible to prevent the rotation of the first size sheet by contacting the side edge of the one size sheet,
A sheet of a second size whose length in the width direction is shorter than the first size is stored in the sheet feeding cassette in which the auxiliary member is attached to the predetermined attachment position, and the attachment operation of the sheet feeding cassette is performed If, and it is possible to suppress the rotation of the sheet of the second size the auxiliary member is in contact with the side edge of the sheet of the second size,
The sheet feeding cassette includes an accommodating portion for accommodating the auxiliary member when the auxiliary member is not used.
The side end restricting means is a first side end restricting member, and a second side end restricting member disposed downstream of the first side end restricting member in the insertion direction of the sheet feeding cassette with respect to the apparatus main body. And
The receiving portion, in the insertion direction of the paper feed cassette, an outer storage area of the sheet of the first size in the paper feeding cassette, and wherein the first side than the second side edge regulating member A sheet feeding device provided at a position close to an end regulating member . The image forming apparatus according to claim 1, wherein the cassette body is provided with an opening for mounting the auxiliary member from above. 3. The sheet feeding device according to claim 1, wherein a groove for guiding the mounting of the auxiliary member from above is formed in the cassette body. The paper feed cassette, in any one of claims 1 to 3, wherein the sheet feeding direction of the length than the first size of the sheet is a high possibility accommodating the second sheet size Sheet feeding apparatus as described. A sheet feeding apparatus according to any one of claims 1 to 4 .
An image forming unit configured to form an image on a sheet fed from the sheet feeding device.

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