JP6685679B2 - Sheet feeding apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet feeding device and an image forming apparatus.

  2. Description of the Related Art Conventionally, image forming apparatuses such as a facsimile machine, a copying machine, and a printer have a sheet feeding device for feeding a sheet toward an image forming unit. The sheet feeding device is detachably attached to the main body of the image forming apparatus, and has a sheet feeding cassette as a sheet storing unit for storing sheets, and a sheet feeding unit for feeding the sheets stored in the sheet feeding cassette. Is equipped with.

  The sheet feeding unit includes a pickup roller that feeds out a sheet stored in a sheet feeding cassette, and a separation unit that has a feed roller and a separation roller for separating the sheet fed by the pickup roller. Further, there is a paper feed cassette provided with a nip guide means for guiding a sheet sent out by a pickup roller to a separation nip portion between a feed roller and a separation roller (see Patent Document 1).

  The nip guide means is formed of an upward inclined surface provided on the downstream side of the sheet feeding direction of the sheet feeding cassette. This inclined surface separates the sheets (shifts one sheet at a time) when a plurality of sheets have been fed by the feeding roller, so that the sheets can be easily separated at the separation nip portion. To guide you.

  Further, there is also one in which guide means integrated with a paper feed cassette are provided on both sides of the nip guide means in the width direction orthogonal to the sheet feeding direction (see Patent Document 2). With this guide means, it becomes possible to smoothly guide the sheet toward the separating portion and the conveying roller arranged downstream of the separating portion without the both ends of the sheet in the width direction hanging down.

JP, 2008-239333, A JP, 2005-350210, A

  In recent years, there has been a demand for downsizing of image forming apparatuses, and sheet feeding apparatuses are also required to be downsized without lowering the sheet feeding performance. Therefore, efficient arrangement of guides and arrangement of rollers are desired in order to reduce the size of the apparatus.

  Therefore, the present invention has been made in view of the above circumstances, and provides a sheet feeding apparatus and an image forming apparatus capable of reducing the size of the apparatus without deteriorating the sheet feeding performance. With the goal.

According to the present invention, in a sheet feeding apparatus, an apparatus main body, a sheet feeding unit provided in the apparatus main body for feeding a sheet in a sheet feeding direction, and a sheet fed by the sheet feeding unit are stored. And a first position for restricting the downstream end in the sheet feeding direction of the sheet, which is provided in the sheet storage device and is retractably mounted in the apparatus main body, and the downstream end. And a contact member that is provided in the apparatus main body and abuts against the restriction member when the sheet storage means is mounted on the apparatus main body , said abutment member, which the moves to an attachment direction of the sheet storage means abuts on the regulating member, wherein the benzalkonium is moved to the second position the regulating member from the first position Is.
Further, according to the present invention, in a sheet feeding apparatus, a sheet storing means that is detachably attached to the apparatus main body in a direction orthogonal to the sheet feeding direction, stores a sheet, and is supported by a shaft in a cantilevered state. Separation for separating a sheet fed from the sheet storage means in a position corresponding to the center of the sheet storage means in a direction orthogonal to the sheet feeding direction with the storage means attached to the apparatus main body. A first regulation that is provided on the roller pair and the sheet storage means, is located upstream of the center of the sheet storage means in the mounting direction of the sheet storage means, and is capable of regulating the leading end of the stored sheets. and the surface, provided in said sheet containing means, the located on the downstream side of the center of the sheet storage means, and regulating the regulating position capable regulating the leading edge of the sheet to be accommodated A second retractable position, which is movably supported by the sheet storage means, and in which the sheet storage means is pulled out from the apparatus main body, the leading end of the stored sheet can be regulated at the regulation position. And a regulating member having a regulating surface of the device main body, and when the sheet storage means is mounted on the apparatus main body, the sheet storage means is located downstream of the center of the sheet storage means in the mounting direction of the sheet storage means. And a third regulation surface that regulates the leading end of the sheet that is located and stored.

  In the present invention, when the sheet storing means is mounted, the regulation member is moved from the first position where the downstream end of the accommodated sheet can be regulated to the position where the downstream end of the sheet is not regulated, thereby feeding the sheet. The device can be downsized without degrading the performance.

FIG. 1 is a diagram showing a schematic configuration of a full-color laser beam printer which is an example of an image forming apparatus including a sheet feeding device according to a first embodiment of the invention. The perspective view explaining the composition of the above-mentioned sheet feeding device. The side view explaining the composition of the above-mentioned sheet feeding device. FIG. 3 is a plan view illustrating a configuration of a sheet feeding cassette provided in the sheet feeding device. FIG. 6A is a diagram showing a state in which a leading edge regulating member provided in the paper feeding cassette is in a regulating position, and FIG. 6B is a diagram showing a state in which the leading edge regulating member is in a retracted position. FIG. 7A is a diagram showing a state of the sheet feeding apparatus according to the second embodiment of the present invention when a sheet feeding cassette is started to be mounted, and FIG. 9B is a sheet feeding cassette of the sheet feeding apparatus. FIG. 6 is a diagram showing a state in which the sheet has reached the feedable position. FIG. 9A is a diagram showing a state of the sheet feeding device according to the third embodiment of the present invention when a sheet feeding cassette is started to be mounted, and FIG. 9B is a sheet feeding cassette of the sheet feeding device. FIG. 6 is a diagram showing a state in which the sheet has reached the feedable position.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a full-color laser beam printer which is an example of an image forming apparatus including a sheet feeding apparatus according to the first embodiment of the present invention.

  As shown in FIG. 1, a full-color laser beam printer (hereinafter, referred to as a printer) 31 includes a printer main body 31A which is an image forming apparatus main body, and an image reading device 32 which is installed substantially horizontally above the printer main body 31A. There is. A sheet discharge space SP for sheet discharge is formed between the image reading device 32 and the printer body 31A. The printer main body 31A includes an image forming unit 31B, and a sheet feeding device 31C that feeds the sheet S from the paper feed cassette 5 as a sheet storage unit that stores the sheet S. The paper feed cassette 5 is detachably attached to the printer body 31A which also serves as the sheet feeding apparatus body. In FIG. 1, the printer 31 defines an upper side of the paper as a front side, a lower side of the paper as a back side, a right side of the paper side as a right side, and a left side as a left side. Therefore, the paper feed cassette 5 is mounted from the front side to the back side of the printer body 31A, and the sheets of the paper feed cassette 5 are fed from the left side to the right side.

  The image forming unit 31B is of a 4-drum full-color type and has four units that form four color toner images of the laser scanner 28 and yellow (Y), magenta (M), cyan (C), and black (K). The process cartridge 36 of FIG. Each process cartridge 36 includes a photosensitive drum 41, a charging device 39 as a charging device, and a developing device 40 as a developing device.

  The image forming unit 31B includes an intermediate transfer unit 31D arranged above the process cartridge 36, a fixing unit 35, and a toner cartridge 43 for supplying toner to the developing device 40. The intermediate transfer unit 31D is provided inside the intermediate transfer belt 29 wound around the driving roller 29a and the tension roller 29b, and is in contact with the intermediate transfer belt 29 at a position facing the photosensitive drum 41. A primary transfer roller 42 is provided. The intermediate transfer belt 29 is rotated in the arrow direction by a driving roller 29a driven by a driving unit (not shown).

  By applying a transfer bias of positive polarity to the intermediate transfer belt 29 by the primary transfer roller 42, toner images of respective colors having a negative polarity on the photoconductor drum are sequentially transferred onto the intermediate transfer belt 29 in an overlapping manner. A secondary transfer roller 37 that constitutes a secondary transfer unit that transfers the color image formed on the intermediate transfer belt to the sheet S is provided at a position facing the drive roller 29a of the intermediate transfer unit 31D. The fixing unit 35 is arranged above the secondary transfer roller 37, and the first discharging roller pair 34, the second discharging roller pair 34a, and the double-sided reversing unit 31E are arranged at the upper left portion of the fixing unit 35.

  Next, the image forming operation of the printer 31 configured as described above will be described. First, when the image information of the document is read by the image reading device 32, this image information is subjected to image processing, then converted into an electric signal and transmitted to the laser scanner 28 of the image forming section 31B. Then, in the image forming unit 31B, the surface of the photosensitive drum 41 of each process cartridge 36 is scanned by the laser light emitted from the laser scanner 28. As a result, the surface of the photosensitive drum 41 whose surface is uniformly charged to a predetermined polarity and potential by the charger 39 is sequentially exposed, and yellow, magenta, and cyan are respectively transferred onto the photosensitive drums of the process cartridges 36. And a black electrostatic latent image is sequentially formed.

  Then, the electrostatic latent image is developed by the developing device 40 with yellow, magenta, cyan, and black color toners to be visualized. After that, the primary transfer bias applied to the primary transfer roller 42 sequentially transfers the toner images of the respective colors on the photosensitive drums onto the intermediate transfer belt 29 so that the toner images are transferred onto the intermediate transfer belt 29. It is formed.

  The sheet S is sent out from the sheet feeding device 31C in parallel with the toner image forming operation, and the sent sheet S is conveyed to the registration roller pair 38. After that, the skew of the sheet S is corrected by the registration roller pair 38, and the sheet S is conveyed to the secondary transfer portion. Then, in this secondary transfer portion, the toner images are collectively transferred onto the sheet S by the secondary transfer bias applied to the secondary transfer roller 37.

  Next, the sheet S on which the toner image is transferred in this manner is conveyed to the fixing unit 35, and the toner image is fixed on the sheet S as a color image by receiving heat and pressure in the fixing unit 35. After that, the sheet S on which the image is fixed is discharged to the paper discharge space SP by the first discharge roller pair 34 or the second discharge roller pair 34a provided on the downstream side of the fixing unit 35, and is discharged to the bottom surface of the paper discharge space SP. It is loaded on the protruding loading section 45. Further, when forming images on both sides, it is reversed by the reversing roller 33 provided in the double-sided reversing section 31E and again conveyed to the image forming section 31B to form an image on the back side, and then is stacked on the stacking section 45. To be done.

  FIG. 2 is a perspective view illustrating the configuration of the sheet feeding device 31C according to the present embodiment, and FIG. 3 is a side view. As shown in FIGS. 2 and 3, the sheet feeding device 31C includes a sheet feeding unit 4 which is a sheet feeding unit, a sheet feeding cassette 5, and the like. The sheet feeding unit 4 is a pickup roller 1, a feed roller 2, and a retard roller which is a separation roller pair that forms a separation roller pair 22 that presses the feed roller 2 so that the plurality of sheets can be separated from each other. 3 and 3. The pickup roller 1, the feed roller 2, and the retard roller 3 are shafts projecting from the back side of the printer body 31A toward the front in the cassette mounting space shown in FIGS. It is attached to 1a, 2a and 3a.

  The pickup roller 1, the feed roller 2, and the retard roller 3 are located substantially at the center of the sheet feeding cassette 5 in the width direction orthogonal to the sheet feeding direction when the sheet feeding cassette is mounted on the printer main body 31A. It is arranged. The shafts 1a, 2a, 3a are supported by the printer main body 31A on the back side and extend to the vicinity of the center, and the pickup roller 1, the feed roller 2 and the retard roller 3 are attached to the ends near the center. There is. That is, the pickup roller 1, the feed roller 2, and the retard roller 3 are cantilevered by the shafts 1a, 2a, 3a, respectively. As a result, the rollers 1, 2, 3 can be replaced by releasing the fixation with the shafts 1a, 2a, 3a and pulling them out toward the shafts 1a, 2a, 3a. The property becomes good.

  The sheet feeding cassette 5 is provided so as to be mounted in the cassette mounting space of the printer main body 31A, and the pickup roller 1 picks up (feeds) the sheet S stored in the sheet feeding cassette 5 mounted in the cassette mounting space. . The feed roller 2 that is a conveyance roller that conveys the picked-up sheet is attached to a feed roller shaft 2a that is rotated by a drive unit (not shown). The retard roller 3 is attached to the retard roller shaft 3a via a torque limiter 8. A retard drive shaft 20 that is rotated by a drive unit (not shown) is provided in parallel with the feed roller shaft 2a and the retard roller shaft 3a. The rotation of the retard drive shaft 20 is transmitted to the retard roller shaft 3a via the retard gear train 21, and further transmitted to the retard roller 3 via the torque limiter 8.

  A roller holder 50 is rotatably held on the feed roller shaft 2a. The pickup roller 1 is rotatably held at the rotating end of the roller holder 50 via a pickup roller shaft 1a. The rotation of the feed roller shaft 2a is transmitted to the pickup roller shaft 1a through the intermediate gear 51, and the pickup roller 1 rotates in the sheet feeding direction while being in contact with the sheet S to feed the sheet.

  The retard roller 3 is driven by the retard drive shaft 20 through the torque limiter 8 to rotate in the direction of feeding the sheet and in the opposite direction with a constant torque. The drive transmission force of the torque limiter 8 (limit value at which drive transmission is interrupted) is set to be larger than the friction force generated between the sheets due to the friction coefficient of the sheets used. Moreover, the drive transmission force of the torque limiter 8 is set to be smaller than the friction force due to the friction coefficient between the sheet and the feed roller 2.

  For this reason, the drive is cut off by the torque limiter 8 when there is only one sheet that enters the nip portion between the feed roller 2 and the retard roller 3 (hereinafter referred to as the separation nip portion) or when there is no sheet. As a result, the retard roller 3 rotates with the rotation of the feed roller 2. Further, when two or more sheets enter the separation nip, the reverse rotation drive from the retard roller shaft 3a is transmitted through the torque limiter 8 and the retard roller 3 rotates in the reverse direction, so that the double feeding of the sheets is performed. To prevent. The pickup roller 1, the feed roller 2, the retard roller 3, the drive transmission mechanism for transmitting the rotation to these rollers, and the like are integrally attached to the sheet feeding frame 4a, and are unitized as the sheet feeding unit 4. . The paper feed frame 4a is attached to the printer body 31A.

  The sheet feeding cassette 5 includes a cassette body 5a that is a box-shaped sheet storage portion that stores sheets, a side regulation plate 5b that regulates the position of the stored sheet S in a width direction orthogonal to the sheet feeding direction, and a sheet S. A rear end regulating plate 5c for regulating the position of the upstream end in the sheet feeding direction is provided. Further, the sheet feeding cassette 5 is provided with an intermediate plate (not shown) that raises the stored sheets to a position where the feed rollers 2 can feed the sheets.

  In the present embodiment, the mounting direction Y1 of the sheet feeding cassette 5 shown in FIG. 2 is the same direction as the width direction Y, in other words, the direction parallel to the axes 1a, 2a, 3a described above. An inner contact surface 6a of the downstream side plate 6 on the downstream side of the cassette body 5a in the sheet feeding direction is provided so that the position of the downstream end (hereinafter, referred to as the leading end) of the sheet in the sheet feeding direction can be regulated. When the paper feed cassette 5 is attached to the printer main body 31A, a conveyance guide 7 that guides the sheet to be fed is formed downstream of the paper feed cassette 5 in the sheet feeding direction. The structure of the transport guide 7 will be described. The downstream side plate 6 has a transport guide portion 71 which is a first guide portion.

  As shown in FIG. 3, the transport guide portion 71 is integrally provided (projected) on the upper end of the downstream side plate 6. The conveyance guide portion 71 includes a contact surface 71b extending vertically upward from the downstream side plate 6, a first inclined surface 71c and a second inclined surface 71c that are formed so that the inclination angle (angle from the horizontal plane) gradually decreases. The surface 71d is provided. The contact surface 71b forming the first regulation surface of the sheet feeding cassette 5 is provided so as to regulate the position of the leading edge of the sheet stored in the sheet feeding cassette 5. Further, the inclined surfaces 71c and 71d are inclined so that the downstream side in the sheet feeding direction is higher than the upstream side in the sheet feeding direction. The first inclined surface 71c is a guide surface that guides the fed sheet to the separation nip portion between the feed roller 2 and the retard roller 3, and the second inclined surface 71d is arranged such that the separated sheet is arranged downstream. It is a guide surface that guides a pair of conveying rollers.

  The transport guide portion 71 is provided at the upper end of the downstream side plate 6 in front of the center in the width direction of the sheet feeding cassette 5. In other words, the transport guide portion 71 is integrally provided on the downstream side plate 6 upstream of the separation roller pair 22 in the mounting direction Y1 of the paper feed cassette 5, and the transport guide portion is integrally provided downstream. Not at all. The conveyance guide portion 71 is arranged so as to be located on the front side of the retard roller 3 when the paper feed cassette 5 is mounted.

  As described above, in the present embodiment, the transport guide portion 71 is not provided on the downstream side plate 6 on the downstream side in the sheet cassette mounting direction Y1. Accordingly, even when the paper feed cassette 5 is mounted in the direction parallel to the shafts 1a, 2a, 3a, the paper feed cassette 5 can be mounted without interfering with the retard roller 3. . The details will be described later.

  As described above, when the transport guide portion 71 is provided only on the upstream side portion of the downstream side plate 6 in the mounting direction Y1 of the sheet feeding cassette, the leading end of the sheet is regulated and fed in the portion where the transport guide portion 71 is not provided. Unable to guide the seat. Therefore, as shown in FIG. 2, when the paper feed cassette 5 is mounted on the printer main body 31A, the main body side conveyance guide portion is located at a position corresponding to the downstream side portion of the downstream side plate 6 in the mounting direction Y1 of the paper feed cassette. 72 is provided. The main body side transport guide portion 72, which is the second guide portion, is fixedly arranged on the back side wall surface of the cassette mounting space A of the printer main body 31A shown in FIG. 4 described below so as to project to the front side of the cassette mounting space A. Has been done.

  That is, in the present embodiment, the transport guide portion is not provided in the entire area of the downstream side plate 6 in the mounting direction Y1 of the sheet feeding cassette, and in the region where the transport guide portion of the downstream side plate 6 is absent, the printer main body 31A has the main body side. A main body side transport guide portion 72, which is a guide portion, is provided. The contact surface 72b for regulating the leading end of the sheet of the main body side conveyance guide portion 72 and the inclined surfaces 72c, 72d for guiding the sheet have the same shape as the contact surface 71b and the inclined surfaces 71c, 71d of the conveyance guide portion 71. is doing.

  When the paper feed cassette 5 is mounted in the cassette mounting space, the main body side transport guide portion 72 is located at a position facing the area of the downstream side plate 6 where the transport guide portion 71 does not exist, and is connected to the transport guide portion 71. Form the same guide surface. As a result, when the paper feed cassette 5 is mounted, the leading end of the stored sheet is regulated by the transport guide portion 71 and the main body side transport guide portion 72 of the cassette main body 5a, and further fed by the pickup roller 1. A conveyance guide 7 for guiding the sheet to be conveyed downstream is configured.

  As described above, the transport guide portion 71 provided in the paper feed cassette 5 is not provided over the entire width of the front end portion of the paper feed cassette 5. The main body side conveyance guide section 72 on the back side of the conveyance guide 7 is provided on the paper feed frame 4a supporting the sheet feeding section 4, and the paper feed frame 4a is attached to the printer main body 31A. Further, as shown in FIGS. 4 and 5, a portion of the sheet feeding cassette 5 facing the main body side transport guide portion 72 is notched so as not to contact the upstream end of the main body side transport guide portion 72. The cutout 6c is formed.

  When the main body side transport guide portion 72 is inserted into the notch 6c, the main body side transport guide portion 72 shown in FIG. 2 constituting the third regulation surface is stacked by the vertical contact surface 72b on the upstream side. The leading edge of the sheet bundle is regulated. That is, when the sheet feeding cassette 5 is mounted in the cassette mounting space A shown in FIG. 4, the main body side transport guide portion 72 is located in the notch 6c, and the main body side transport guide portion 72 shown in FIG. The surface 72b and the contact surface 6a of the downstream side plate 6 of the paper feed cassette 5 form substantially the same surface. The contact surface 6a of the downstream side plate 6, the contact surface 72b of the main body side transport guide portion 72, and the contact surface 71b of the transport guide portion 71 constitute a leading edge regulation surface that regulates the position of the leading edge of the sheet. .

  Here, the reason why the transport guide portion 71 is provided separately will be described. For example, when the conveyance guide 7 is integrally provided in the widthwise direction Y of the sheet feeding cassette 5 in which the sheet S is conveyed, when the sheet feeding cassette 5 is inserted in the mounting direction Y1, The guide 7 and the sheet feeding section 4 may interfere with each other. For example, due to variations in the mounting position of rails or the like that support the movement of the paper feed cassette 5 in the printer main body 31A and the dimensions of the parts, and variations in the mounting position of the sheet feeding unit 4, the transport guide 7 is attached when the paper feed cassette 5 is mounted. May collide with the sheet feeding unit 4. Therefore, if a gap is provided in the sheet feeding direction in order to avoid interference between the sheet feeding unit 4 and the sheet feeding cassette 5, the sheet feeding cassette 5 and the sheet feeding unit 4 must be sufficiently separated. However, the size of the device is increased.

  Therefore, in the present embodiment, when the sheet feeding cassette 5 is attached, the sheet is fed to a position on the front side of the sheet feeding cassette 5 in the attaching direction Y1 and out of the rollers 1, 2, and 3 of the sheet feeding unit 4. The guide portion 71 is integrally formed. Further, on the back side of the paper feed cassette 5 in the mounting direction Y1, a main body side conveyance guide section 72 is provided separately from the paper feed cassette 5.

  Therefore, when the paper feed cassette 5 is attached to the printer main body 31A, the main body side transport guide portion is provided on the back side of the paper feed cassette 5 so that the main body side transport guide portion 72 and the paper feed cassette 5 do not interfere with each other. A notch 6c is formed so as to escape 72. In this way, by disposing the conveyance guide 7 by dividing it into the sheet feeding cassette 5 and the printer main body 31A, when mounting the sheet feeding cassette 5 in the cassette mounting space, a gap is provided in the sheet feeding direction. Instead, the sheet feeding cassette 5 and the sheet feeding unit 4 can be arranged. Therefore, the size of the device in the sheet feeding direction can be reduced. Further, since the paper feed cassette 5 is integrally provided with the transport guide portion 71, when the paper feed cassette 5 is pulled out, the cantilevered retard roller 3 can be pulled out to the front side for replacement. .

  By the way, when a sheet is set in the sheet feeding cassette 5 for replenishing the sheet, the sheet feeding cassette 5 is pulled out from the cassette mounting space A, and when the sheet is set in this state, when the sheet storage amount is large, The leading ends of the plurality of sheets face the notch 6c. At this time, since there is nothing to regulate the leading end of the sheet on the back side of the sheet feeding cassette 5, the sheet S is set at an angle, or the sheet S is loaded in the middle of loading the sheet feeding cassette 5 in the cassette loading space A. May become slanted.

  When the sheet S is inclined with respect to the sheet feeding cassette 5, the corner portion of the leading end of the sheet S may be in a state of protruding from the sheet feeding cassette 5 downstream in the sheet feeding direction. When the paper feed cassette 5 is inserted into the printer body 31A in this state, the sheet S is caught by the sheet feeding unit 4 on the printer body 31A side, and the sheet is damaged. Further, if the sheet S is fed in a state of being set obliquely, there is a possibility that a sheet feeding failure such as a jam (paper jam) may occur.

  In the present embodiment, as shown in FIGS. 4 and 5, the sheet feeding cassette 5 is set in an area where the conveyance guide portion 71 is not provided, that is, in a position where the conveyance guide portion 71 does not overlap. A leading edge regulating member 10 which is a regulating means for regulating the leading edge of the sheet is provided. Accordingly, when the sheet feeding cassette 5 is set, the leading edge of the sheet can be regulated in the area of the sheet feeding cassette 5 where the transport guide portion 71 is not provided.

  The tip regulation member 10 is formed in a plane parallel to the mounting direction by the rotation shaft 101 provided on the outer surface 6b at the central portion in the widthwise region of the cutout 6c of the downstream side plate 6 of the cassette body 5a shown in FIG. It is rotatably supported in a plane parallel to the outer side surface 6b. The mounting position of the front end regulation member 10 in the width direction is not limited to this, and may be arranged so as to correspond to different sizes of the stored sheets. The leading edge regulating member 10 projects upward from the downstream side plate 6 shown in FIG. 5A and is the first position for regulating the leading edge of the set sheet, and the downstream side plate shown in FIG. 5B. It is possible to move to a retracted position that is a second position that does not project from 6. It should be noted that when the paper feed cassette 5 is pulled out from the cassette mounting space A of the printer main body 31A, the tip regulation member 10 is biased by a spring 102 that is a biasing member to rotate upward, and a stopper (not shown) is provided. By being brought into contact with, it is held at the regulation position shown in FIG.

  When the leading end regulating member 10 is located at the regulating position, it forms the same surface as the abutting surface 6a that abuts the sheet S of the downstream side plate 6 as shown in FIG. It has a regulation surface 10a as a second regulation surface that regulates the sheet on the downstream side in the direction. Further, the tip regulation member 10 has the same length as the upper end 71a of the conveyance guide portion 71 when it is in the regulation position, or has a length protruding upward from the upper end 71a of the conveyance guide portion 71 as shown in FIG. There is. Further, the tip regulation member 10 has a length that does not interfere with the transport guide portion 71 when rotated to the retracted position.

  Even when the amount of stored sheets S is large by the leading edge regulation member 10, the leading edge of the sheet S to be stored is in the regulation position, and the abutting surface 71b of the conveyance guide portion 71 is located. And the contact surface 6a of the downstream side plate 6 regulates. For this reason, even when the storage amount of the sheet S is large, the tip corner portion of the sheet does not project downstream in the sheet feeding direction. A notch 6d having an open upper portion is formed in the notch 6c on the upstream side in the mounting direction Y1 of the sheet feeding cassette 5. The notch 6d is provided to prevent the restriction surface 10a from interfering with the downstream side plate 6 when the tip restriction member 10 moves to the retracted position.

  On the upstream side of the printer body 31A in the mounting direction Y1 of the paper feed cassette 5 on the retard roller 3, a contact member 9 is provided as an operating means that comes into contact with the leading end regulating member 10 when the paper feed cassette 5 is mounted. Has been. The abutting member 9 is provided so as to come into contact with the leading edge regulating member 10 before the sheet feeding cassette 5 reaches a feedable position where a sheet can be fed by the pickup roller 1 which is a predetermined mounting position. There is. In the present embodiment, the contact member 9 is provided on the paper feed frame 4a of the printer body 31A as shown in FIG.

  When the paper feed cassette 5 is pushed into the cassette mounting space A from the mounting direction Y1 for mounting, the tip regulating member 10 contacts the abutting member 9, and the tip regulating member 10 rotates against the biasing force of the spring 102. It rotates downward around the moving shaft 101 as a fulcrum. When the paper feed cassette 5 is further pushed in, the leading edge regulating member 10 is lower than the upper end 71a of the transport guide portion 71, in other words, below the sheet feeding path through which the sheet fed by the pickup roller 1 passes. Rotate downward to the retracted position. As a result, the leading edge regulating member 10 does not interfere with the sheet feeding.

  The leading edge regulating member 10 that has moved to the retracted position as described above is housed below the contact member 9 as shown in FIG. 5B by the time the paper feed cassette 5 reaches the feedable position. That is, in the present embodiment, the contact member 9 contacts the tip regulation member 10 to rotate the tip regulation member 10 downward, and then is positioned above the tip regulation member 10 to retract the tip regulation member 10. Configured to hold in position. Further, when the paper feed cassette 5 is pulled out from the printer main body 31A, the front end regulating member 10 that has moved to the retracted position is rotated upward by the elastic force of the spring 102 when the contact with the contact member 9 is released. It returns to the regulation position shown in FIG.

  As shown in FIG. 2 described above, the contact member 9 is located upstream of the main assembly side transport guide portion 72 in the mounting direction. Further, a nip guide 9a having an inclined surface inclined with respect to a horizontal plane for guiding the sheet to the separation nip portion is arranged adjacent to the contact member 9. The nip guide 9a is arranged between the conveyance guide portion 71 and the main body side conveyance guide portion 72, and is formed to have a width substantially the same as the width of the separation nip portion in the width direction. The nip guide 9a has a function of displacing the front end of the sheet by the inclined surface when a plurality of sheets are fed by the pickup roller 1, and by displacing the front end of the sheet, the sheet is separated by the separation nip portion. I am trying to ensure separation.

  As described above, in the present embodiment, the tip regulation member 10 is provided on the upper surface of the downstream side plate 6 on the downstream side in the mounting direction of the transport guide portion 71 so as to be movable to the regulation position and the retracted position. Accordingly, in order to prevent the guide means from interfering with the separation roller or the like, even if the conveyance guide portion is not provided on the inner side of the paper feed cassette 5, the leading edge regulating member 10 can prevent the sheet from protruding. As a result, it is possible to prevent damage to the sheet and defective feeding of the sheet due to the sheet being caught when the sheet cassette 5 is mounted. Accordingly, it is possible to provide a sheet feeding device capable of smoothly feeding a sheet while reducing the size of the device.

  Further, in the present embodiment, the sheet feeding cassette 5 is moved to the retracted position from the regulation position by bringing the leading end regulation member 10 into contact with the contact member 9 immediately before being mounted in the feedable position. ing. As a result, even when the leading edge regulating member 10 is provided, the sheet can be fed.

  Next, a second embodiment of the present invention will be described with reference to FIG. 6A is a diagram showing a state of the sheet feeding device according to the present embodiment when the sheet feeding cassette 5 is started to be mounted, and FIG. 6B is a diagram showing the sheet feeding device. FIG. 6 is a diagram showing a state when the paper feed cassette 5 reaches a feedable position. In FIG. 6, the same reference numerals as those in FIG. 5 described above indicate the same or corresponding portions.

  In the present embodiment, as shown in FIG. 6, when the sheet is set in the sheet feeding cassette 5 in a region of the sheet feeding cassette 5 where the conveyance guide portion 71 is not provided, the regulation for regulating the leading edge of the sheet is performed. A tip regulation member 11 which is a means is provided. The tip regulation member 11 is provided on the outer surface 6b of the downstream side plate 6 of the cassette body 5a, and is parallel to the outer surface 6b by a slide guide 12 that is inclined so that the downstream side in the mounting direction is higher than the upstream side in the mounting direction. It is slidably supported by.

  The tip end regulation member 11 is urged to the downstream side in the mounting direction Y1 of the paper feed cassette 5 by a biasing member such as a spring (not shown), and the paper feed cassette 5 is pulled out from the cassette mounting space A of the printer body 31A. In the state in which it is in contact, it abuts on a stopper (not shown). Then, by contacting the stopper, the sheet S protrudes from the same as the upper end 71a of the conveyance guide portion 71, or as shown in FIG. Is held in the restricted position. As a result, when the sheet S is set in the sheet feeding cassette 5, the sheet S comes into contact with the leading edge regulating member 11 that has moved to the regulating position, and does not project downstream in the sheet feeding direction.

  When the paper feed cassette 5 comes into contact with the abutting member 9 in the process of mounting the paper feed cassette 5 in the printer main body 31A from the mounting direction Y1, the tip end regulation member 11 resists the biasing force of the biasing member and follows the slide guide 12. While descending, it slides upstream in the mounting direction Y1. Then, after this, the leading edge regulating member 11 moves to the outside of the sheet conveying path as shown in FIG. 6B by the time the paper feed cassette 5 reaches the feedable position. Then, in the state in which the paper feed cassette 5 is mounted at the feedable position, the leading end regulating member 11 is pressed by the contact member 9 and held at the retracted position.

  As described above, by sliding the leading edge regulating member 11 to the retracted position outside the sheet conveyance path before the sheet feeding cassette 5 reaches the feeding possible position, the leading edge regulating member 11 feeds the sheet during sheet feeding. It is possible to prevent it from being blocked. When the paper feed cassette 5 is pulled out from the printer main body 31A, the tip end regulation member 11 is released along the slide guide 12 by the biasing member and is lifted along the slide guide 12 when the contact member 9 is released. 6 and slides back to the regulation position shown in FIG.

  As described above, in the present embodiment, the tip regulation member 11 that is slidable to the regulation position and the retracted position is provided on the upper surface of the downstream side plate 6 on the downstream side in the mounting direction of the transport guide portion 71. Furthermore, before the paper feed cassette 5 is mounted at the feedable position, the leading end regulating member 11 is brought into contact with the abutting member 9 to move from the regulating position to the retracted position.

  As described above, the tip regulation member 11 is slidably provided, and the tip regulation member 11 is moved from the regulation position to the retracted position before the paper feed cassette 5 is mounted at the feeding possible position. The same effects as those of the first embodiment can be obtained.

  Next, a third embodiment of the present invention will be described with reference to FIG. 7A is a diagram showing a state of the sheet feeding device according to the present embodiment when the sheet feeding cassette 5 is started to be mounted, and FIG. 7B is a diagram showing the sheet feeding device. FIG. 6 is a diagram showing a state when the paper feed cassette 5 reaches a feedable position. In FIG. 7, the same reference numerals as those in FIG. 5 described above indicate the same or corresponding portions.

  In the present embodiment, as shown in FIG. 7, when the sheet is set in the sheet feeding cassette 5 in a region of the sheet feeding cassette 5 where the conveyance guide portion 71 is not provided, the regulation is performed to regulate the leading edge of the sheet. A tip regulation member 13 which is a means is provided. The leading end regulating member 13 is a sheet feeding unit that is rotatably supported by a bearing 131a provided to face the outer surface 6b of the downstream side plate 6 of the cassette body 5a and has a pivot shaft 131 parallel to the mounting direction Y1 as a fulcrum. It is supported rotatably in the feeding direction. Note that FIG. 7 shows only one bearing 131a.

  In addition, when the paper feed cassette 5 is pulled out from the cassette mounting space A of the printer body 31A, the leading end regulation member 13 is biased by a biasing member such as a spring (not shown) to rotate upward, Abut on a stopper (not shown). Then, by contacting the stopper, as shown in FIG. 7A, the sheet S is held at the regulation position for regulating the leading edge of the sheet S. As a result, when the sheet S is set in the sheet feeding cassette 5, the sheet S comes into contact with the leading edge regulation member 13 that has moved to the regulation position, and does not project downstream in the sheet feeding direction.

  At the downstream end of the tip regulation member 13 in the mounting direction, there is an abutting surface that is twisted in the clockwise direction as it goes to the downstream side in the mounting direction. It is provided. As a result, when the abutting portion 13a comes into contact with the abutting member 9 in the process of mounting the paper feed cassette 5 in the printer main body 31A, the rotary shaft 131 rotates integrally with the abutting portion 13a, and accordingly The tip regulation member 13 rotates downward against the biasing force of the biasing member. After that, the leading edge regulating member 10 becomes parallel to the outer side surface 6b outside the sheet conveying path as shown in FIG. 7B by the time the sheet feeding cassette 5 reaches the feedable position. Rotate to the position.

  In the present embodiment, the downstream side plate 6 is provided with a cutout 6e. In this way, by providing the notch 6e, it is possible to prevent the abutting portion 13a that rotates integrally with the rotating shaft 131 from interfering with the outer surface 6b of the downstream side plate 6 when the tip regulating member 13 is rotated downward. be able to. The abutting portion 13a and the notch 6e come into contact with the sheet stored in the cassette body 5a when the abutting portion 13a enters the cassette body 5a when the tip regulating member 13 is rotated downward. It is provided in a position that never happens.

  As described above, before the sheet feeding cassette 5 reaches the sheet feedable position, the leading edge regulating member 13 is rotated downward and moved to the retreat position outside the sheet conveying path. Can prevent the sheet from being fed. Note that, when the paper feed cassette 5 is pulled out from the printer main body 31A, the tip end regulation member 13 is pivoted upward by the biasing member when the contact with the contact member 9 is released, and as shown in FIG. Return to the regulation position shown.

  As described above, in the present embodiment, the tip regulation member 13 that is movable to the regulation position and the retracted position is provided on the upper surface of the downstream plate 6 on the downstream side in the mounting direction of the transport guide portion 71. Further, before the paper feed cassette 5 is mounted at the feedable position, the leading end regulating member 13 is brought into contact with the abutting member 9 to move from the regulating position to the retracted position.

  As described above, the tip regulation member 13 is rotatably provided, and the tip regulation member 13 is moved from the regulation position to the retracted position before the paper feed cassette 5 is attached to the feeding possible position. The same effects as those of the first and second embodiments described above can be obtained.

DESCRIPTION OF SYMBOLS 1 ... Pickup roller, 2 ... Feed roller, 3 ... Retard roller, 4 ... Sheet feeding part (sheet feeding means), 5 ... Paper feed cassette (sheet storing means), 5a ... Cassette body, 6 ... Downstream side plate, 6c ... Notches, 9 ... Abutting member (actuating means), 10 ... Tip regulating member, 10a ... Regulating surface (second regulating surface), 11 ... Tip regulating member, 12 ... Slide guide, 13 ... Tip regulating member, 13a. ... abutting section, 31 ... full-color laser beam printer (image forming apparatus), 31A ... printer body (apparatus body), 31B ... image forming section, 31C ... sheet feeding apparatus, 7 ... conveyance guide, 71 ... conveyance guide section ( 1st guide part), 71b ... Contact surface (1st control surface), 72 ... Main body side conveyance guide part (2nd guide part), 72b ... Contact surface (3rd control surface), 101 ... Rotation axis, 102 ... (Biasing member), 131 ... rotation axis, A ... cassette mounting space, S ... Sheet

Claims (22)

The device body,
A sheet feeding unit provided in the apparatus main body for feeding a sheet in a sheet feeding direction;
A sheet storage means for storing a sheet to be fed by the sheet feeding means, the sheet storing means being detachably attached to the apparatus main body;
A regulating member provided in the sheet accommodating means and movable between a first position capable of regulating the downstream end of the accommodated sheets in the sheet feeding direction and a second position not regulating the downstream end;
A contact member that is provided in the apparatus main body and contacts the regulating member when the sheet storage means is attached to the apparatus main body ;
Said abutment member, said moves to an attachment direction of the sheet storage means abuts on the regulating member, wherein the benzalkonium is moved to the second position the regulating member from the first position sheet Feeding device. A cutout provided in the sheet storage means, in the state where the sheet storage means is attached to the apparatus main body, a notch in which the sheet feeding means is located,
When the sheet storage means is attached to the apparatus main body, the sheet storage means includes a regulation surface provided on the sheet storage means and a regulation surface provided on the apparatus body, and is stored in the sheet storage means. The sheet feeding device according to claim 1, further comprising: a leading edge regulating surface that is capable of regulating the downstream end of the sheet.   The sheet feeding device according to claim 2, wherein the regulation member has a regulation surface that forms the same plane as the regulation surface of the sheet storage unit and that regulates the sheet from jumping out at the cutout. A first guide portion which is provided in the sheet storage means and is arranged upstream of the sheet feeding means when the sheet storage means is attached to the apparatus main body in a mounting direction; ,
A second guide portion for guiding a sheet, which is provided in the apparatus main body and is arranged on the downstream side in the mounting direction with respect to the first guide portion when the sheet storage means is mounted in the apparatus main body; ,,
4. The sheet feeding device according to claim 2, wherein each of the first guide portion and the second guide portion is provided with a regulation surface that constitutes the leading edge regulation surface.   The sheet feeding device according to claim 4, wherein the regulation member is arranged at a position different from the first guide portion in the mounting direction of the sheet storage means.   The sheet feeding device according to claim 4, wherein the restriction member projects upward from the first guide portion at the first position. A biasing member that biases the regulating member from the second position to the first position in order to return the regulating member from the second position to the first position when the sheet storage means is pulled out from the apparatus main body. sheet feeding apparatus according to any one of claims 1 to 6, characterized in that it comprises means. The regulation member is rotatably provided in a plane parallel to the mounting direction of the sheet storage means, and the contact member contacts the regulation member as the sheet storage means moves in the mounting direction. The sheet feeding device according to any one of claims 1 to 7 , wherein the regulating member is rotated. The abutting member comes into contact with the regulating member and rotates downward when the sheet accommodating means is attached to the apparatus main body, and then is positioned above the regulating member to move the regulating member to the second position. The sheet feeding device according to claim 8, which is held in a position. The regulation member is provided so as to be slidable in a plane parallel to the mounting direction of the sheet storage means, and the contact member contacts the regulation member as the sheet storage means moves in the mounting direction. The sheet feeding device according to any one of claims 1 to 7 , wherein the regulating member is slid and moved. The sheet storage means has a slide guide that is inclined so that the downstream side in the mounting direction of the sheet storage means is higher than the upstream side in the mounting direction, and the regulation member is slidably supported by the slide guide. sheet feeding apparatus according to claim 1 0, wherein that. The restricting member is supported rotatably in the sheet feeding direction by an axis parallel to the mounting direction of the sheet storage means, and the abutting member is moved along with the movement of the sheet storage means in the mounting direction. sheet feeding apparatus according to any one of claims 1 to 7, characterized in that rotating the regulating member abuts against the regulating member in the sheet feeding direction. The restricting member has an abutting surface twisted so as to rotate the restricting member downward toward the downstream side in the mounting direction, and the abutting member contacts the abutting surface. sheet feeding apparatus according to claim 1 2, wherein the rotating the regulating member sheet feeding direction. Mounting direction of said sheet accommodating means to a sheet feeding apparatus according to any one of claims 1 to 1 3, characterized in that a direction perpendicular to the sheet feeding direction. A sheet storing means for storing a sheet, which is detachably attached to the apparatus main body in a direction orthogonal to the sheet feeding direction,
The sheet storage unit is supported in a cantilevered state on a shaft and is arranged at a position corresponding to the center of the sheet storage unit in a direction orthogonal to the sheet feeding direction with the sheet storage unit attached to the apparatus main body. A pair of separating rollers for separating sheets fed from the means,
A first restricting surface provided on the sheet accommodating means, located upstream of the center of the sheet accommodating means in the mounting direction of the sheet accommodating means, and capable of restricting the leading edge of the accommodated sheet;
The sheet storage unit is provided in the sheet storage unit, is located on the downstream side of the center of the sheet storage unit, and is movable between a regulation position where the front end of the stored sheet can be regulated and a retracted position where the sheet is not regulated. And a regulation member having a second regulation surface capable of regulating the leading end of the accommodated sheet at the regulation position in a state in which the sheet accommodation means is pulled out from the apparatus main body,
When the sheet storage means provided in the apparatus main body is attached to the apparatus main body, the sheets stored in the sheet storage means are located downstream from the center of the sheet storage means in the mounting direction of the sheet storage means. A third regulation surface that regulates the tip,
A sheet feeding device comprising: The separating roller pair includes a paper feed frame supporting, the paper feed frame into the third claims 1-5 sheet feeding apparatus, wherein the provision of the regulating surface. A notch for allowing the third restriction surface to enter is provided on the downstream side of the center in the mounting direction of the sheet storage means, and the restriction member is arranged corresponding to the notch. The sheet feeding device according to claim 15 or claim 16 . Claim 1 5 to 1 7, characterized in that said sheet containing means is provided with actuating means for moving said regulating member along with being mounted on the apparatus main body in the retracted position from the regulating position to the device body The sheet feeding device according to claim 1. The restricting member is movably supported between the restricting position and the retracted position by rotating, and the restricting position is adjusted by the actuating means as the sheet storage means is mounted on the apparatus main body. The sheet feeding device according to claim 18 , wherein the sheet feeding device is rotated from the retracted position to the retracted position. The regulation member is slidably supported so as to be movable between the regulation position and the retreat position, and the regulation position is regulated by the actuating means along with the operation of mounting the sheet storage means on the apparatus main body. The sheet feeding device according to claim 18 , wherein the sheet feeding device is slid from the retracted position to the retracted position. The restricting member is movably supported between the restricting position and the retracted position by an axis parallel to the mounting direction of the sheet storage means, and the sheet storing means is attached to the apparatus main body during the operation. The sheet feeding apparatus according to claim 18, wherein the actuating means is rotated from the restricted position to the retracted position. An image forming apparatus comprising: an image forming unit; and the sheet feeding device according to claim 1 , which feeds a sheet toward the image forming unit.

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