Image forming device

Abstract

To provide an image formation device capable of preventing a sheet from being rotated due to an impact when sheet storage means is inserted.SOLUTION: A side end position in a width direction of a sheet of a predetermined size stored in a sheet feed cassette 60, is regulated by a depth-side side regulating member 80 and a front-side side regulating member 81 provided on an upstream side of a depth-side side regulating plate 61 and a front-side side regulating plate 62 in a sheet feeding direction. Then, when a sheet of a small size S3 having a shorter width in the width direction than the sheet of the predetermined size is stored in the sheet feed cassette 60, an auxiliary side regulating member 82 is attached to the depth-side regulating member 80 and the front-side regulating member 81, thereby regulating the side end position in the width direction of sheet of the small size S3.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus, and more particularly to a configuration for regulating the position of a sheet. [Background technology]

[0002] In recent years, image forming apparatuses such as copiers, printers, and facsimiles have become widespread in which sheets stored in a sheet storage means are fed to an image forming section to form an image. Such sheet storage means include a plate-shaped sheet stacking means for stacking sheets that can be raised and lowered.

[0003] When replenishing sheets, the sheet stacking means is lowered, and when feeding sheets, the sheet stacking means is raised to move the top surface of the stacked sheets to a position where they can be fed by the pickup roller above. Also, the sheet storage means is provided in the device body so that it can be pulled out, and when storing sheets, the sheet storage means is pulled out and then the sheets are set on the sheet stacking means from above.

[0004] The sheet storage means is provided with a rear end regulating means movable along the sheet feeding direction that regulates the position of the upstream end (hereinafter referred to as the rear end) of sheets stacked on the sheet stacking means in the sheet feeding direction so that sheets of different sizes can be stored.The sheet storage means is also provided with a side end regulating means movable in the width direction that regulates the side end position of the sheets in a direction perpendicular to the sheet feeding direction (hereinafter referred to as the width direction).The side end regulating means regulates the side end of the sheet, and the rear end regulating means regulates the position of the sheet to a predetermined position (see Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 3359174 Summary of the Invention [Problem to be solved by the invention]

[0006] However, if the paper feed cassette is subjected to an impact when it is inserted, the sheets will rotate, which can cause the sheets to shift inside the paper feed cassette, resulting in the image on the sheet being misaligned or the sheet being skewed, resulting in the image being formed on the sheet at an angle.

[0007] Therefore, the present invention has been made in consideration of the current situation, and aims to provide an image forming apparatus that can prevent sheets from rotating due to impact when inserting them into a sheet storage means. [Means for solving the problem]

[0008] One aspect of the present invention is a sheet storage unit that stores sheets, is detachably attached to an image forming apparatus main body, and is attached to the image forming apparatus main body by being inserted in an insertion direction; a sheet feeding unit that feeds the sheets stored in the sheet storage unit attached to the image forming apparatus main body in a direction perpendicular to the insertion direction by a roller arranged on the leading edge side of the sheets; an image forming unit that forms an image on the sheets fed by the sheet feeding unit; and a sheet storage unit that is attached to the sheet storage unit so as to be movable in a sheet width direction parallel to the insertion direction. , Shi of Side edge a side edge regulating means for regulating the position of the sheet; and a side edge regulating means provided on the sheet storing means so as to be movable in a direction perpendicular to the insertion direction. , Shi The rear end of the Seat width The sheet is in contact with the center in the direction rear end A rear end regulating means for regulating the position and a rear end regulating means for regulating the position of the sheet and , which is fixed in place when a specific size sheet is stored. ,before The sheet of the specific size is connected to the downstream side edge in the insertion direction. do an auxiliary regulating means, the auxiliary regulating means being attachable to and detachable from the sheet storing means independently of the trailing edge regulating means, and the trailing edge regulating means being movable independently of the auxiliary regulating means; the predetermined position is closer to the rear end of the specific size sheet than the side end regulating means, and when the auxiliary regulating means is attached to the predetermined position and the specific size sheet is stored in the sheet storage means, when the sheet storage means is inserted in the insertion direction and attached to the image forming apparatus main body, the auxiliary regulating means abuts against the rear end side of the specific size sheet, thereby regulating the rear end side of the specific size sheet from moving downstream in the insertion direction.The image forming apparatus is characterized by the above. [Effects of the Invention]

[0009] According to the present invention, it is possible to prevent the seat from rotating. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram 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; [Figure 2] 2A and 2B are diagrams illustrating the configuration of a mounting portion of the full-color laser beam printer and a paper feed cassette that is detachably mounted in the mounting portion. [Figure 3] 5A and 5B are diagrams illustrating a configuration of a front side regulating member provided in the paper feed cassette. [Figure 4] 10A and 10B are diagrams illustrating an operation of attaching an auxiliary side regulating member to the front side regulating member. [Figure 5] 10A and 10B are diagrams illustrating a state in which sheets of different sizes are stored in the paper feed cassette. [Figure 6] FIG. 10 is a diagram showing the configuration of a conventional paper feed cassette. DETAILED DESCRIPTION OF THE INVENTION

[0011] An example of a sheet feeding device of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a diagram showing the 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. In FIG. 1, 1 is a full-color laser beam printer (hereinafter referred to as printer), 1A is a printer main body which is the main body of the image forming apparatus, 1B is an image forming section which forms an image on a sheet, and 20 is a fixing section. 2 is an image reading device which is an upper device installed approximately horizontally above the printer main body 1A, and a discharge space P is formed between this image reading device 2 and the printer main body 1A. 30 is a sheet feeding device provided below the printer main body 1A, and 15 is a toner cartridge.

[0012] Image information read by the image reading device 2 or image information input from an external device such as a personal computer (not shown) is image processed, converted into an electrical signal, and transmitted to a 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 image information of yellow, magenta, cyan, and black component colors emitted from the laser scanner 10. As a result, the surface of the photosensitive drum 12, the surface of which has been uniformly charged to a predetermined polarity and potential by the charger 13, is sequentially exposed to light, and electrostatic latent images of yellow, magenta, cyan, and black are sequentially formed on the photosensitive drum of each process cartridge 11, respectively.

[0013] Thereafter, the developing unit 14 develops and visualizes this electrostatic latent image with yellow, magenta, cyan, and black toner. Then, a primary transfer bias is applied to the primary transfer roller 19, and the toner images of each color on each photosensitive drum are transferred onto the intermediate transfer belt 16 in a sequentially overlapping manner. As a result, a toner image is formed on the intermediate transfer belt 16.

[0014] Meanwhile, the sheet S sent out from the sheet feeding device 30 passes through a pair of registration rollers 40 and is sent to a secondary transfer section made up of a drive roller 16a and a secondary transfer roller 17. In the secondary transfer section, the toner images formed in the image forming section 1B are transferred all at once onto the sheet S. Next, the sheet S onto which the toner images have been transferred in this manner is transported to the fixing section 20, where the toner images are fixed to the sheet S as a color image by application of heat and pressure.

[0015] Thereafter, the sheet S on which the image has been fixed is discharged into the discharge space P by the pair of discharge rollers 25a, 25b, and is stacked on a stacking section 23 that protrudes from the bottom surface of the discharge space P. When forming images on both sides of the sheet S, after the images have been fixed, the sheet S is transported to a re-conveyance path R by a pair of reversible reversing rollers 22 provided in the double-side reversing section 1D, and then transported again to the image forming section 1B.

[0016] Here, a sheet feed cassette 60, which serves as a sheet storage means, is detachably mounted in a mounting portion 1E (shown in FIG. 2) formed at the bottom of the printer main body 1A. As shown in FIG. 2, the sheet feed cassette 60 is provided with a rear side regulating plate 61 that is movable in the depth direction and that regulates the position of the sheet S in one of the depth directions (width directions) perpendicular to the sheet feeding direction, i.e., the downstream side in the depth direction. The sheet feed cassette 60 is also provided with a front side regulating plate 62 that is movable in the depth direction and faces the rear side regulating plate 61 and regulates the upstream side in the depth direction of the sheet S. The rear side regulating plate 61 and the front side regulating plate 62 that constitute a pair of side edge regulating means 61A move in conjunction with each other by a linkage mechanism (not shown) to regulate the upstream and downstream side edge positions of the sheet in the depth direction.

[0017] The sheet feed cassette 60 is also provided with a rear end regulating plate 63 that is movable along the sheet feed direction and that regulates the position of the rear end, which is the upstream end in the sheet feed direction, of the sheets S. The sheet feed cassette 60 is also provided with a middle plate (not shown) on which sheets are stacked, and the positions of the sheets stacked on this middle plate are regulated by the rear side regulating plate 61, the front side regulating plate 62, and the rear end regulating plate 63.

[0018] A swing arm 64 having a swing pin 65 at its tip is supported on a rear side wall 60a of the cassette body 60A of the paper feed cassette 60 so as to be swingable about a shaft 64a as a fulcrum. Also, a retraction unit 66, which is a retraction means for retracting the paper feed cassette 60 into the mounting section 1E, is disposed on the inner wall surface on the rear side of the mounting section 1E. The retraction unit 66 includes a retraction unit base 69 and a retraction arm 68 having a retraction hook 67 at its tip and supported on the retraction unit base 69 so as to be rotatable about a fulcrum 70.

[0019] A recess 91 for engaging the swing pin 65 of the swing arm 64 is formed in the retraction hook 67 of the retraction arm 68. An arm pin 71 is provided between the retraction hook 67 of the retraction arm 68 and the fulcrum 70, and one end of a tension spring 73 is engaged with the other end of the tension spring 73, the other end of which is engaged with a base pin 72 provided on the retraction unit base 69. The retraction arm 68 is biased by the tension spring 73 to rotate around the fulcrum 70.

[0020] When the paper feed cassette 60 is pulled out, while the recess 91 is locking the swing pin 65, the retractable arm 68 rotates counterclockwise from the position shown in FIG. 2 around the fulcrum 70 in the pulling direction against the tension spring 73. If the paper feed cassette 60 is subsequently pulled out further, the retractable arm 68 rotates to the standby position where the locking of the swing pin 65 by the recess 91 is released. If the retractable arm 68 rotates a predetermined amount before rotating to the standby position, the tension spring 73 applies a force to the retractable arm 68 to rotate it counterclockwise. This force causes the retractable arm 68 to move to the standby position and then come into contact with a stopper (not shown) to stop it.

[0021] When the retractable arm 68 is in the standby position, the retractable arm 68 is in a position where the swing pin 65 of the swing arm 64 enters the recess 91 of the retractable hook 67 when the paper feed cassette 60 is attached to the printer main body 1A. Therefore, when the paper feed cassette 60 is inserted into the attachment section 1E, the swing pin 65 enters the recess 91 of the retractable hook 67. If the paper feed cassette 60 is then pushed further in, the swing pin 65 and the retractable hook 67 press the retractable arm 68 toward the rear.

[0022] As a result, the retractable arm 68 rotates clockwise around the fulcrum 70 against the tension spring 73, and then, when it rotates to a predetermined position, the retractable arm 68 rotates clockwise due to the biasing force of the tension spring 73. Then, as the retractable arm 68 rotates clockwise in this manner, the recess 91 of the retractable hook 67 engages with the swing pin 65. As a result, when the retractable arm 68 rotates due to the tension spring 73, the paper feed cassette 60 is attached while receiving a biasing force in the depth direction from the tension spring 73 via the retractable arm 68.

[0023] 2, a positioning portion 74 is provided at one end (right end) of the cassette body 60A on the upstream side in the depth direction, perpendicular to the depth direction, to position the sheet feed cassette 60 in the depth direction when the sheet feed cassette 60 is installed. When the sheet feed cassette 60 is installed, the positioning portion 74 positions the sheet feed cassette 60 in the depth direction. After the sheet feed cassette 60 is installed, a middle plate that is provided on the cassette body 60A so as to be rotatable in the vertical direction is lifted, and the sheets S on the middle plate come into contact with a pickup roller 75.

[0024] 2, a rear side regulating member 80 is provided on the upstream side of the rear side wall 60a in the sheet feeding direction, and a front side regulating member 81 is provided on the upstream side of the front side wall 60b of the cassette body 60A in the sheet feeding direction. The widthwise distance between the rear side regulating member 80 and the front side regulating member 81 constituting the pair of upstream end regulating means 80A is set to correspond to the maximum sheet width that can be accommodated in the sheet cassette 60.

[0025] In this embodiment, since the maximum sheet size is LGL, the widthwise distance between the rear side regulating member 80 and the front side regulating member 81 is set to the LGL width, and Fig. 2 shows a state when an LGL-sized sheet S1 is stored. The rear side regulating plate 61, the front side regulating plate 62, the trailing edge regulating plate 63, the rear side regulating member 80, and the front side regulating member 81 prevent the sheet S1 from shifting position within the sheet feed cassette 60.

[0026] 3, the front side regulating member 81 has a regulating portion (regulating surface) 81a on its side that regulates the widthwise position of a sheet of a predetermined size (an LGL size sheet) that has the maximum sheet width among the sheets that can be accommodated in the sheet cassette 60. Note that the rear side regulating member 80 has the same configuration, so only the front side regulating member 81 will be described below.

[0027] Further, this front side regulating member 81 is provided with an attachment space 81c for selectively attaching an auxiliary side regulating member 82, which is an auxiliary side edge regulating means, through an opening at the top. Here, the auxiliary side regulating member 82 regulates the widthwise position of small-sized sheets that are smaller than the maximum sheet width that can be accommodated in the paper feed cassette 60, and has a protrusion 82a that abuts against the side edge of the small-sized sheet.

[0028] Furthermore, a slit groove 81b, which is an opening extending in the vertical direction and allowing the protrusion 82a to protrude from the front side regulating member 81 toward the sheet when the auxiliary side regulating member 82 is attached, is formed in the center of the regulating portion 81a of the front side regulating member 81 in the sheet feeding direction. As a result, when the auxiliary side regulating member 82 is inserted from the opening at the top of the attachment space of the front side regulating member 81 as shown in Fig. 4A, the protrusion 82a of the auxiliary side regulating member 82 protrudes from the front side regulating member 81 toward the inside of the cassette body as shown in Fig. 4B. Note that a slide groove (not shown) extending in the vertical direction is formed on the back side of the regulating portion 81a to guide the attachment of the auxiliary side regulating member 82 from above into the attachment space 81c.

[0029] In this embodiment, when small-sized sheets are stored in the sheet feed cassette 60, auxiliary side regulating members 82 are attached to the rear side regulating member 80 and the front side regulating member 81. This makes it possible to regulate the side edge positions of small-sized sheets stored in the sheet feed cassette 60.

[0030] 3 and 4, an auxiliary member accommodating portion 83 is provided adjacent to the front side wall 60b of the cassette body 60A at a position that does not interfere with the stacking of sheets near the front side regulating member 81. When the auxiliary side regulating member 82 is not used, that is, when sheets of the maximum sheet width are stored in the paper feed cassette 60, the auxiliary side regulating member 82 is stored in the auxiliary member accommodating portion 83. This makes it possible to prevent the auxiliary side regulating member 82 from being lost.

[0031] 5(b), the regulating width set by auxiliary side regulating members 82 attached to rear side regulating member 80 and front side regulating member 81 is set to A4 width (210 mm), which is smaller than LGL width (215.9 mm). When storing sheets of a smaller size, for example, when the regulating width is to be set to B5 width (182 mm), auxiliary side regulating members whose protrusion amount from slit groove 81b is set to B5 width are prepared.

[0032] In this embodiment, the positions of the rear side regulating member 80 and the front side regulating member 81 in the sheet feeding direction are set to positions that allow them to regulate the side edges of LTR (215.9 mm) and A4 (210 mm) size sheets. (a) of FIG. 5 shows a state in which an LTR size sheet S2 is stored in the paper feed cassette 60. When an LTR size sheet S2 is stored, the rear end of the sheet S2 abuts against the regulating surfaces of the regulating portion 80a of the rear side regulating member 80 and the regulating portion 81a of the front side regulating member 81, thereby regulating the widthwise position of the sheet S2.

[0033] 5(b) shows a state in which A4-sized sheets S3 are stored in the sheet cassette 60. When storing A4-sized sheets S3 in this manner, auxiliary side regulating members 82 are attached to the rear side regulating member 80 and the front side regulating member 81, as described above. As a result, when A4-sized sheets S3 are stored, the rear end of the sheets S3 abuts against the protrusions 82a that form the regulating surfaces of the auxiliary side regulating members 82, thereby regulating the widthwise position of the sheets S3. When storing LGL, which is the maximum sheet size in this embodiment, the sheets are stored with the auxiliary side regulating members 82 removed, as the sheet width of the LGL is the same as the sheet width of the LTR, as shown in FIG.

[0034] As described above, when storing sheets that are shorter in the depth direction (width direction) than sheets of a predetermined size, auxiliary side regulating members 82 are attached to rear side regulating member 80 and front side regulating member 81 to regulate the side edge positions of the sheets. This makes it possible to prevent the sheets from rotating due to the impact when inserting paper feed cassette 60. As a result, the sheets can be supplied to image forming unit 1B in a state where skew and misalignment are suppressed, and image misalignment on the sheets can be suppressed.

[0035] In this embodiment, auxiliary side regulating member 82 is configured to slide in the sheet stacking direction and be detached. Therefore, when storing sheets, even if the user touches auxiliary side regulating member 82 or inserts paper feed cassette 60 with great force, auxiliary side regulating member 82 will not easily come off rear side regulating member 80 and front side regulating member 81. As a result, auxiliary side regulating member 82 can reliably regulate the widthwise position of the sheets. [Explanation of symbols]

[0036] 1...full-color laser beam printer, 1A...printer body, 1B...image forming unit, 1E...mounting unit, 60...paper feed cassette, 60A...cassette body, 60a...rear side wall of cassette body, 60b...front side wall of cassette body, 61...rear side regulating plate, 61A...side end regulating means, 62...front side regulating plate, 63...rear end regulating plate, 80...rear side regulating member, 80A...upstream end regulating means, 81...front side regulating member, 81a...regulating portion, 81b...slit groove, 81c...mounting space, 82...auxiliary side regulating member, 82a...protrusion, 83...auxiliary member accommodating section, S, S1, S2, S3...sheet

Claims

1. a sheet storage means for storing sheets, which is detachably attached to the image forming apparatus main body and is attached to the image forming apparatus main body by being inserted in an insertion direction; a sheet feeding means for feeding the sheets stored in the sheet storing means attached to the image forming apparatus body in a direction perpendicular to the insertion direction by a roller disposed on the leading edge side of the sheets; an image forming unit that forms an image on the sheet fed by the sheet feeding means; a side edge regulating means provided in the sheet storing means so as to be movable in a sheet width direction parallel to the insertion direction, and regulating the position of a side edge of the sheet; a rear end regulating means provided in the sheet storing means so as to be movable in a direction perpendicular to the insertion direction, the rear end regulating means contacting a central portion of the rear end of the sheet in the sheet width direction to regulate the position of the rear end of the sheet; an auxiliary regulating means that is detachable from the sheet storing means, is attached to a predetermined position when a sheet of a specific size is stored, and comes into contact with a downstream side edge of the sheet of the specific size in the insertion direction, the auxiliary regulating means is detachable from the sheet storing means independently of the trailing edge regulating means, the trailing edge regulating means is movable independently of the auxiliary regulating means, the predetermined position is located on the rear end side of the sheet of the specific size from the side end regulating means, When the sheet storage means is inserted into the image forming apparatus main body in the insertion direction and the sheet of the specific size is stored in the sheet storage means with the auxiliary regulating means attached at the predetermined position, the auxiliary regulating means abuts against the rear end side of the sheet of the specific size, thereby regulating the rear end side of the sheet of the specific size from moving downstream in the insertion direction. An image forming apparatus characterized by:

2. The side edge regulating means is positioned in a direction perpendicular to the insertion direction such that the distance between the rear end of the sheet of the specific size and the end position of the contact point between the side edge of the sheet on the side edge regulating means and the rear end of the sheet is greater than the distance between the front end of the sheet of the specific size and the end position of the contact point between the side edge of the sheet on the side edge regulating means and the front end of the sheet.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. The predetermined position in the auxiliary regulating means is set at a position in which, in a direction perpendicular to the insertion direction, the distance between the rear end of the sheet of the specific size and the end position of the auxiliary regulating means at the contact point with the side edge of the sheet on the rear end side of the sheet is smaller than the distance between the front end of the sheet of the specific size and the end position of the side edge regulating means at the contact point with the side edge of the sheet on the front end side of the sheet.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

4. The auxiliary regulating means contacts the vicinity of the rear end of the side edge of the sheet of the specific size.

4. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

5. a length in a direction perpendicular to the insertion direction of a contact point between the auxiliary regulating means positioned at the predetermined position and the side edge of the specific size sheet, the length in a direction perpendicular to the insertion direction of the specific size sheet, the length in a direction perpendicular to the insertion direction of the contact point between the side edge of the specific size sheet and the side edge regulating means, 5. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

6. The sheet of the specific size whose side edge is regulated by the auxiliary regulating means is stored in the sheet storing means with the side edge intersecting the insertion direction being the long side and the short side aligned with the insertion direction.

6. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

7. The sheet storage means and the auxiliary regulating means are configured so that the auxiliary regulating means can be attached to the sheet storage means by sliding downward, and the auxiliary regulating means can be detached from the sheet storage means by sliding upward.

7. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

8. The sheet storage means has an opening on the outer side in the sheet width direction with respect to a space for storing the sheets, The sheet storage means and the auxiliary regulating means are configured so that the auxiliary regulating means is attached to the sheet storage means by inserting a part of the auxiliary regulating means into the opening from above, and the auxiliary regulating means, the part of which is inserted into the opening of the sheet storage means, is moved upward to remove the auxiliary regulating means from the sheet storage means.

8. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

9. The sheet storage means is provided with an opening that is positioned outside the side edge of the specific size sheet in the sheet width direction and above the bottom surface of the sheet storage means on which the sheets are loaded in the sheet loading direction, and into which a part of the auxiliary regulating means is inserted from above, The auxiliary regulating means is inserted into the opening from above, and thereby the position of the auxiliary regulating means relative to the sheet storing means in the sheet width direction is determined.

8. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

10. A hole into which a lower portion of the auxiliary regulating means is inserted is provided on the bottom surface of the sheet storage means.

10. The image forming apparatus according to claim 9,

11. The auxiliary regulating means is configured to be detachably attached to a plurality of positions in the sheet storing means.

11. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

12. further comprising a retracting means for urging the sheet storage means in the insertion direction to retract the sheet storage means into a mounting position; 12. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

13. The auxiliary regulating means is not screwed to the seat storage means.

13. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

14. The seat storage means includes a storage section for storing the auxiliary regulating means when the auxiliary regulating means is not in use, the storage section is provided upstream of the specific size sheets in the insertion direction.

14. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

Images