JP2017057052A - Sheet feeding device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet feeding device and an image forming apparatus that can be miniaturized without degrading a sheet feeding performance.SOLUTION: A downstream plate 6 in a casette body 5a is provided with a notch 6c, and the notch 6c is provided with a leading edge regulation member 10 that is movable to a first position where a leading edge of a sheet is regulated and a second position where the leading edge of the sheet is not regulated while projecting upward from the downstream plate 6. A sheet casette 5 is moved from the first position to the second position with the leading edge regulation member 10 contacting an abutment member 9 when mounted on a printer body.SELECTED DRAWING: Figure 5

Description

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

  2. Description of the Related Art Conventionally, an image forming apparatus such as a facsimile machine, a copying machine, or a printer includes a sheet feeding device for feeding a sheet toward an image forming unit. The sheet feeding device is detachably attached to the apparatus main body of the image forming apparatus, and includes a sheet feeding cassette as a sheet storing unit that stores sheets, and a sheet feeding unit that feeds the sheets stored in the sheet feeding cassette. It has.

  The sheet feeding unit includes a pickup roller that feeds out a sheet stored in the sheet feeding cassette, and a separation unit that includes a feed roller and a separation roller for separating the sheet fed by the pickup roller. In addition, there is a paper feed cassette provided with nip guide means for guiding a sheet fed 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 in the sheet feeding direction of the sheet feeding cassette. This inclined surface makes it easy to separate the sheets at the separation nip portion by rolling the sheets (shifting one sheet at a time) when a plurality of sheets have been sent out by the feeding roller. To guide.

  Further, there is a type in which guide means integrated with the sheet feeding 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). By this guide means, it is possible to smoothly guide the sheet toward the separation unit and the conveyance roller disposed downstream of the separation unit without both ends of the sheet in the width direction hanging.

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

  In recent years, downsizing of an image forming apparatus has been demanded, and also in a sheet feeding apparatus, it is demanded to downsize without lowering the sheet feeding performance. Therefore, in order to reduce the size of the apparatus, an efficient guide arrangement and each roller arrangement are desired.

  Therefore, the present invention has been made in view of such a current situation, and provides a sheet feeding apparatus and an image forming apparatus that can reduce the size of the apparatus without deteriorating the sheet feeding performance. With the goal.

  The present invention provides a sheet feeding apparatus, wherein the apparatus main body, a sheet feeding means provided in the apparatus main body, for feeding sheets, and a sheet fed by the sheet feeding means are stored, and the apparatus main body A sheet storage unit that is detachably mounted in the mounting space, and a notch that is provided in the sheet storage unit and in which the sheet feeding unit is positioned in the state where the sheet storage unit is mounted in the mounting space. In the state where the sheet storage means is mounted in the mounting space, the sheet storage means includes a restriction surface provided in the sheet storage means and a restriction surface provided in the apparatus main body, and is stored in the sheet storage means. A first-end regulating surface capable of regulating the downstream end of the sheet, and a first end capable of regulating the downstream end of the stored sheet provided corresponding to the notch of the sheet storage means. A restricting member movable between the first position and the second position, and when the sheet storage means is mounted in the mounting space, the restricting member is moved from the first position to the first position. And actuating means for moving to two positions.

  In the present invention, when the sheet storage means is mounted, the regulating member is moved from the first position where the downstream end of the stored sheet can be regulated to a position where the downstream end of the sheet is not regulated, thereby feeding the sheet. The apparatus can be reduced in size without degrading performance.

1 is a diagram illustrating 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 present invention. FIG. 3 is a perspective view illustrating a configuration of the sheet feeding device. The side view explaining the structure of the said sheet feeding apparatus. FIG. 3 is a plan view illustrating a configuration of a sheet feeding cassette provided in the sheet feeding apparatus. (A) is a figure which shows a state when the front-end | tip control member provided in the said paper feed cassette exists in a control position, (b) is a figure which shows a state when the said front-end | tip control member exists in a retracted position. (A) is a figure which shows the state when the paper feeding cassette starts mounting | wearing of the sheet feeding apparatus which concerns on the 2nd Embodiment of this invention, (b) is the paper feeding cassette of the said sheet feeding apparatus. The figure which shows a state when reaches the position which can be fed. (A) is a figure which shows the state when a sheet feeding cassette starts to be mounted in the sheet feeding apparatus according to the third embodiment of the present invention, and (b) is a sheet feeding cassette of the sheet feeding apparatus. The figure which shows a state when reaches the position which can be fed.

  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 provided with 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 that is an image forming apparatus main body, and an image reading device 32 that is installed substantially horizontally above the printer main body 31A. Yes. A sheet discharge space SP for sheet discharge is formed between the image reading device 32 and the printer main 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 sheet feeding cassette 5 as a sheet storage unit that stores the sheet S. The paper feed cassette 5 is attached to the printer main body 31A, which also serves as the sheet feeding apparatus main body, so that it can be pulled out. In FIG. 1, the printer 31 is defined as a front side on the top of the page, a back side on the bottom of the page, a right side on the right side and a left side on the left side. Accordingly, the paper feed cassette 5 is mounted from the front side to the back side of the printer main 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 four-drum full-color system, and forms four toner images of the laser scanner 28 and four colors of yellow (Y), magenta (M), cyan (C), and black (K). The process cartridge 36 is provided. Each process cartridge 36 includes a photosensitive drum 41, a charger 39 as a charging unit, and a developing unit 40 as a developing unit.

  The image forming unit 31B includes an intermediate transfer unit 31D disposed 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 drive roller 29a and the tension roller 29b, and contacts 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 direction of the arrow by a driving roller 29a driven by a driving unit (not shown).

  By applying a positive transfer bias to the intermediate transfer belt 29 by the primary transfer roller 42, each color toner image having a negative polarity on the photosensitive drum is sequentially transferred onto the intermediate transfer belt 29. A secondary transfer roller 37 constituting a secondary transfer unit that transfers a color image formed on the intermediate transfer belt to the sheet S is provided at a position facing the driving roller 29a of the intermediate transfer unit 31D. A fixing unit 35 is disposed above the secondary transfer roller 37, and a first discharge roller pair 34, a second discharge roller pair 34a, and a double-side reversing unit 31E are disposed at the upper left part of the fixing unit 35.

  Next, an image forming operation of the printer 31 configured as described above will be described. First, when image information of a document is read by the image reading device 32, the image information is subjected to image processing, converted into an electrical signal, and transmitted to the laser scanner 28 of the image forming unit 31B. 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, cyan on the photosensitive drum of each process cartridge 36, respectively. And an electrostatic latent image of black are sequentially formed.

  Then, the electrostatic latent image is developed and visualized by the developing device 40 with yellow, magenta, cyan and black toners. Thereafter, the toner images are transferred onto the intermediate transfer belt 29 by sequentially superimposing and transferring the color toner images on the photosensitive drums onto the intermediate transfer belt 29 by the primary transfer bias applied to the primary transfer roller 42. It is formed.

  In parallel with the toner image forming operation, the sheet S is sent out from the sheet feeding device 31 </ b> C, and the sent sheet S is conveyed to the registration roller pair 38. Thereafter, the sheet S is corrected in skew by the registration roller pair 38 and conveyed to the secondary transfer unit. In the 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 has been transferred in this manner is conveyed to the fixing unit 35, and the toner image is fixed to the sheet S as a color image by receiving heat and pressure in the fixing unit 35. Thereafter, the sheet S on which the image has been fixed is discharged into the paper discharge space SP by the first discharge roller pair 34 or the second discharge roller pair 34a provided downstream of the fixing unit 35, and on the bottom surface of the paper discharge space SP. It is loaded on the protruding loading unit 45. Further, when forming images on both sides, the image is reversed by the reversing roller 33 provided in the double-side reversing unit 31E and transported again to the image forming unit 31B to form an image on the back surface, and then loaded on the stacking unit 45. Is 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 31 </ b> C includes a sheet feeding unit 4 that is a sheet feeding unit, a sheet feeding cassette 5, and the like. The sheet feeding unit 4 includes a pickup roller 1, a feed roller 2, and a retard roller that is a separation roller that constitutes a separation roller pair 22 that is in pressure contact with the feed roller 2 and separates a plurality of sheets one by one. 3 is provided. The pickup roller 1, the feed roller 2, and the retard roller 3 are shafts that protrude toward the front of the hand from the back side of the printer main body 31A in a cassette mounting space shown in FIGS. 4 and 5 (described later) provided in the lower part of the printer main body 31A. It is attached to 1a, 2a, 3a.

  The pickup roller 1, the feed roller 2 and the retard roller 3 are positioned substantially at the center of the paper feed cassette 5 in the width direction perpendicular to the sheet feeding direction when the paper feed cassette is mounted on the printer main body 31A. Has been placed. The shafts 1a, 2a, and 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. Yes. That is, the pickup roller 1, the feed roller 2, and the retard roller 3 are supported in a cantilevered manner on the shafts 1a, 2a, and 3a, respectively. Thus, the rollers 1, 2 and 3 can be replaced by releasing the fixation with the shafts 1a, 2a and 3a and pulling them forward with respect to the shafts 1a, 2a and 3a. Property is improved.

  The paper feed cassette 5 is provided so as to be mountable 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 paper feed cassette 5 mounted in the cassette mounting space. . A feed roller 2 that is a transport roller for transporting 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 3 a 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 3 a 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 via the intermediate gear 51, and the pickup roller 1 feeds out the sheet by rotating in the sheet feeding direction while being in contact with the sheet S.

  The retard roller 3 is applied with a constant torque by the retard drive shaft 20 via the torque limiter 8 in the direction opposite to the rotation in the direction in which the sheet is fed. The drive transmission force of the torque limiter 8 (the limit value at which drive transmission is interrupted) is set to be larger than the friction force generated between the sheets depending on the friction coefficient of the used sheet. In addition, 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.

  Therefore, when the number of sheets entering the nip portion (hereinafter referred to as the separation nip portion) between the feed roller 2 and the retard roller 3 is one or no sheet is present, the drive is cut by the torque limiter 8. 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, reverse rotation drive from the retard roller shaft 3a is transmitted via the torque limiter 8, and the retard roller 3 rotates reversely, thereby double feeding the sheets. To prevent. The pickup roller 1, the feed roller 2, the retard roller 3, a drive transmission mechanism for transmitting rotation to these rollers, and the like are integrally attached to the sheet feeding frame 4a and are unitized as a sheet feeding unit 4. . The paper feed frame 4a is attached to the printer main body 31A.

  The sheet feeding cassette 5 includes a cassette body 5a that is a box-shaped sheet storage unit that stores sheets, a side regulation plate 5b that regulates the position in the width direction orthogonal to the sheet feeding direction of the stored sheets S, and the sheet S. A rear end regulating plate 5c for regulating the position of the upstream end in the sheet feeding direction is provided. In addition, the paper feed cassette 5 includes a middle plate (not shown) that raises the stored sheet to a position where the sheet can be fed by the feed roller 2.

  In the present embodiment, the mounting direction Y1 of the paper feed cassette 5 shown in FIG. 2 is the same direction as the width direction Y, in other words, a direction parallel to the axes 1a, 2a, 3a already described. The contact surface 6a on the downstream side plate 6 on the downstream side in the sheet feeding direction of the cassette body 5a is provided so as to be able to regulate the position of the downstream end (hereinafter referred to as the leading end) of the sheet in the sheet feeding direction. In a state where the paper feed cassette 5 is mounted on the printer main body 31A, a conveyance guide 7 for guiding the fed sheet is configured downstream of the paper feed cassette 5 in the sheet feeding direction. The structure of this conveyance guide 7 is demonstrated. The downstream side plate 6 has a conveyance guide portion 71 that is a first guide portion.

  As shown in FIG. 3, the transport guide portion 71 protrudes (disposes) integrally with the upper end of the downstream side plate 6. The conveyance guide unit 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 formed so that an inclination angle (an angle from a horizontal plane) gradually decreases. A surface 71d is provided. The contact surface 71 b constituting the first regulating 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. 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 disposed downstream of the separated sheet. It is a guide surface which guides to the conveyance roller pair which exists.

  The transport guide portion 71 is provided on the front side of the upper end of the downstream side plate 6 with respect to the center in the width direction of the paper feed cassette 5. In other words, the conveyance 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 conveyance guide portion is integrally provided downstream. Not. The transport guide portion 71 is disposed so as to be positioned in front of the retard roller 3 when the paper feed cassette 5 is mounted.

  As described above, in the present embodiment, the conveyance guide portion 71 is not provided on the downstream side plate 6 on the downstream side in the sheet feeding cassette mounting direction Y1. Thus, 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. . Details of this will be described later.

  As described above, when the conveyance guide portion 71 is provided only in the upstream portion of the downstream side plate 6 in the sheet feeding cassette mounting direction Y1, the leading edge of the sheet is regulated and fed in a portion where the conveyance guide portion 71 is not provided. The sheet cannot be guided. For this reason, as shown in FIG. 2, when the paper feed cassette 5 of the printer main body 31A is mounted, the main body side transport guide portion is located at a position corresponding to the downstream side portion of the downstream side plate 6 in the paper feed cassette mounting direction Y1. 72 is provided. The main body side conveyance guide portion 72 as the second guide portion is fixedly arranged so as to protrude toward the front side of the cassette mounting space A on the back side wall surface of the cassette mounting space A of the printer main body 31A shown in FIG. Has been.

  In other words, in the present embodiment, the conveyance guide portion is not provided in the entire area of the downstream side plate 6 in the paper feed cassette mounting direction Y1, and the printer main body 31A is connected to the main body side in a region where the conveyance guide portion of the downstream side plate 6 is not provided. A main body side conveyance guide portion 72 which is a guide portion is provided. The contact surface 72b that regulates the leading edge of the sheet of the main body-side conveyance guide portion 72 and the inclined surfaces 72c and 72d that guide the sheet have the same shape as the contact surface 71b and the inclined surfaces 71c and 71d of the conveyance guide portion 71. doing.

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

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

  When the main body side conveyance guide portion 72 enters the notch 6c, the main body side conveyance guide portion 72 is stacked by the vertical contact surface 72b on the upstream side of the main body side conveyance guide portion 72 shown in FIG. The leading edge of the sheet bundle is regulated. That is, when the paper feed cassette 5 is mounted in the cassette mounting space A shown in FIG. 4, the main body side transport guide portion 72 is positioned in the notch 6c, and the main body side transport guide portion 72 shown in FIG. The surface 72b and the abutment surface 6a of the downstream side plate 6 of the paper feed cassette 5 constitute substantially the same surface. The abutment surface 6a of the downstream plate 6, the abutment surface 72b of the main body side conveyance guide portion 72, and the abutment surface 71b of the conveyance guide portion 71 constitute a leading edge regulating surface that regulates the position of the leading edge of the sheet. .

  Here, the reason why the conveyance guide portion 71 is provided in a divided manner will be described. For example, when the conveyance guide 7 is integrally provided in the entire width direction Y of the conveyance region in which the sheet S is conveyed of the sheet cassette 5, the conveyance is performed when the sheet cassette 5 is inserted in the mounting direction Y <b> 1. There is a possibility that the guide 7 and the sheet feeding unit 4 interfere with each other. For example, the conveyance guide 7 is attached when the paper feed cassette 5 is mounted due to variations in the mounting position of a rail or the like that supports the movement of the paper feeding cassette 5 in the printer main body 31A, variations in component dimensions, and variations in the mounting position of the sheet feeding unit 4. May collide with the sheet feeding unit 4. Therefore, when a gap is provided in the sheet feeding direction 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 from each other. This leads to an increase in the size of the device.

  Therefore, in the present embodiment, when the sheet feeding cassette 5 is mounted on the front side in the mounting direction Y1 of the sheet feeding cassette 5, the sheet is transported to a place that is separated from the rollers 1, 2, 3 of the sheet feeding unit 4. The guide part 71 is integrally formed. In addition, a main body side conveyance guide portion 72 is provided on the back side in the mounting direction Y1 of the paper feed cassette 5 separately from the paper feed cassette 5.

  For this reason, when the paper feed cassette 5 is mounted on the printer main body 31A, the main body side transport guide portion is disposed 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 6 c is formed so as to escape 72. As described above, the conveyance guide 7 is divided into the paper feed cassette 5 and the printer main body 31A, thereby providing a gap in the sheet feeding direction when the paper feed cassette 5 is mounted in the cassette mounting space. The sheet feeding cassette 5 and the sheet feeding unit 4 can be arranged. Therefore, it is possible to reduce the size of the apparatus in the sheet feeding direction. In addition, since the conveyance guide unit 71 is integrally provided in the paper feed cassette 5, when the paper feed cassette 5 is pulled out, the cantilevered retard roller 3 can be pulled out toward the front side to be replaced. .

  By the way, when a sheet is set in the sheet feeding cassette 5 for replenishment of the sheet or the like, the sheet feeding cassette 5 is pulled out from the cassette mounting space A, and when the sheet is loaded in this state, The leading ends of the plurality of sheets face the notch 6c. At this time, there is nothing that regulates the leading edge of the sheet at the back side of the sheet feeding cassette 5, so the sheet S is set obliquely or the sheet S is in the middle of loading the sheet feeding cassette 5 in the cassette mounting space A. May become slanted.

  If the sheet S is inclined with respect to the sheet feeding cassette 5, the corner of the leading edge of the sheet S may protrude from the sheet feeding cassette 5 downstream in the sheet feeding direction. When the sheet feeding cassette 5 is inserted into the printer main body 31A in this state, the sheet S is caught by the sheet feeding unit 4 on the printer main body 31A side, and the sheet is damaged. Further, if the sheet S is fed from a state in which it is set obliquely, there is a risk of causing a sheet feeding failure such as a jam (paper jam).

  In the present embodiment, as shown in FIGS. 4 and 5, the sheet feeding cassette 5 is set in a region where the conveyance guide portion 71 on the back side is not provided, that is, in a position not overlapping with the conveyance guide portion 71. A leading edge regulating member 10 that is a regulating means for regulating the leading edge of the sheet is provided. Thereby, when the paper feed cassette 5 is set, the leading edge of the sheet can be regulated in an area where the conveyance guide portion 71 of the paper feed cassette 5 is not provided.

  The front end regulating member 10 is arranged in a plane parallel to the mounting direction by a rotation shaft 101 provided on the outer side surface 6b of the central portion in the region in the width direction of the notch 6c of the downstream side plate 6 of the cassette body 5a shown in FIG. Is supported so as to be rotatable in a plane parallel to the outer surface 6b. The attachment position of the front end regulating member 10 in the width direction is not limited to this, and the tip restricting member 10 may be arranged so as to correspond to different sizes of the stored sheets. The leading edge regulating member 10 protrudes upward from the downstream side plate 6 shown in FIG. 5A, and is a regulation position that is a 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 protrude from 6. The front end regulating member 10 is urged by a spring 102 as an urging member and rotated upward in a state where the paper feed cassette 5 is pulled out from the cassette mounting space A of the printer main body 31A, and a stopper (not shown). Is held at the restricting 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 against the sheet S of the downstream side plate 6 as shown in FIG. It has a regulating surface 10a as a second regulating surface that regulates the sheet on the downstream side in the direction. Further, the tip restricting member 10 has the same length as the upper end 71a of the conveyance guide portion 71 or a length protruding upward from the upper end 71a of the conveyance guide portion 71 as shown in FIG. Yes. Further, the tip regulating member 10 has a length that does not interfere with the conveyance guide portion 71 when it is rotated to the retracted position.

  Even if the storage amount of the sheet S is large due to the leading edge regulating member 10, the leading edge of the stored sheet S is positioned at the regulating position, and the contact surface 71 b of the conveyance guide portion 71. And it is regulated by the contact surface 6 a of the downstream side plate 6. For this reason, even when the storage amount of the sheet S is large, the leading end corner portion of the sheet does not protrude downstream in the sheet feeding direction. Note that a notch 6d having an open top is formed on the notch 6c upstream of the sheet feeding cassette 5 in the mounting direction Y1. The notch 6d is provided to prevent the regulating surface 10a from interfering with the downstream side plate 6 when the tip regulating member 10 moves to the retracted position.

  An abutting member 9 is provided on the upstream side of the printer main body 31A in the mounting direction Y1 of the sheet feeding cassette 5 on the retard roller 3 as an operating means that abuts against the leading end regulating member 10 when the sheet feeding cassette 5 is mounted. It has been. This abutting member 9 is provided so as to abut on the leading edge regulating member 10 before reaching the feedable position where the sheet feeding cassette 5 can feed the sheet by the pickup roller 1 which is a predetermined mounting position. Yes. In the present embodiment, the contact member 9 is provided on the paper feed frame 4a of the printer main body 31A as shown in FIG.

  When the paper feeding cassette 5 is inserted into the cassette mounting space A from the mounting direction Y1 for mounting, the front end regulating member 10 abuts against the abutting member 9, and the front end regulating member 10 rotates against the urging force of the spring 102. It pivots downward with the moving shaft 101 as a fulcrum. When the sheet feeding cassette 5 is further pushed in, the leading end regulating member 10 is lower than the upper end 71a of the conveyance 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 hinder sheet feeding.

  The tip regulating member 10 thus moved to the retracted position is accommodated below the contact member 9 as shown in FIG. 5B until the paper feed cassette 5 reaches the feedable position. That is, in the present embodiment, the contact member 9 contacts the tip restriction member 10 and rotates the tip restriction member 10 downward, and then is positioned above the tip restriction member 10 and retracts the tip restriction member 10. Configured to hold in position. Further, when the leading edge regulating member 10 moved to the retracted position is released from the contact member 9 when the paper feeding cassette 5 is pulled out from the printer main body 31A, the tip regulating member 10 is rotated upward by the elastic force of the spring 102. Returning to the restriction position shown in FIG.

  As shown in FIG. 2 described above, the contact member 9 is located upstream of the main body side conveyance guide portion 72 in the mounting direction. A nip guide 9 a having an inclined surface that is inclined with respect to a horizontal plane that guides the sheet to the separation nip portion is disposed adjacent to the contact member 9. The nip guide 9a is disposed between the conveyance guide portion 71 and the main body side conveyance guide portion 72, and is formed to have substantially the same width as the separation nip portion in the width direction. The nip guide 9a has a function of shifting the leading edge of the sheet by the inclined surface when a plurality of sheets have been sent out by the pickup roller 1, and the sheet is moved by the separation nip portion by shifting the leading edge of the sheet. Ensures separation.

  As described above, in the present embodiment, the tip restricting member 10 is provided on the upper surface of the downstream side plate 6 on the downstream side in the mounting direction of the conveyance guide portion 71 so as to be movable to the restricting position and the retracted position. Accordingly, even if the conveyance guide portion is not provided on the back side of the sheet feeding cassette 5 so that the guide means does not interfere with the separation roller or the like, 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 poor sheet feeding due to catching of the sheet when the sheet feeding cassette 5 is mounted. As a result, it is possible to provide a sheet feeding apparatus that can smoothly feed sheets while downsizing the apparatus.

  Further, in the present embodiment, immediately before the paper feed cassette 5 is mounted at the feedable position, the front end regulating member 10 is brought into contact with the abutting member 9 and moved from the regulated position to the retracted position. ing. Thereby, even when the leading end 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 illustrating a state of the sheet feeding apparatus according to the present embodiment when the sheet feeding cassette 5 starts to be mounted, and FIG. 6B is a diagram illustrating the sheet feeding apparatus. FIG. 6 is a diagram illustrating a state when the paper feed cassette 5 has reached a feedable position. In FIG. 6, the same reference numerals as those in FIG. 5 described above indicate the same or corresponding parts.

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

  The leading edge regulating member 11 is urged downstream 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 main body 31A. In this state, it abuts against a stopper (not shown). Then, by contacting the stopper, the upper end 71a of the conveyance guide portion 71 is the same as the upper end 71a or protrudes upward from the upper end 71a of the conveyance guide portion 71 as shown in FIG. To be held in the restricted position. Thereby, when the sheet S is set in the sheet feeding cassette 5, the sheet S comes into contact with the leading end regulating member 11 moved to the regulating position, and does not protrude downstream in the sheet feeding direction.

  When the paper feed cassette 5 comes into contact with the contact member 9 in the process in which the paper feed cassette 5 is attached to the printer main body 31A from the attachment direction Y1, the front end regulating member 11 moves along the slide guide 12 against the urging force of the urging member. While descending, it slides and moves upstream in the mounting direction Y1. Thereafter, the leading edge regulating member 11 moves out of the sheet conveyance path as shown in FIG. 6B until the paper feed cassette 5 reaches the feedable position. In a state where 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, the leading edge regulating member 11 is slid to the retracted position outside the sheet conveyance path before the sheet feeding cassette 5 reaches the feedable position. It can prevent obstructing sending. When the contact with the contact member 9 is released when the paper feed cassette 5 is pulled out from the printer main body 31A, the leading end regulating member 11 is moved along the slide guide 12 while being lifted along the slide guide 12 and downstream in the mounting direction. And move back to the restricting position shown in FIG.

  As described above, in the present embodiment, the tip regulating member 11 that can slide to the regulating 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 conveyance guide portion 71. Further, before the paper feeding cassette 5 is mounted at the feedable position, the leading end regulating member 11 is brought into contact with the abutting member 9 and moved from the regulating position to the retracted position.

  As described above, the tip restricting member 11 is slidably provided, and the tip restricting member 11 is moved from the restricting position to the retracted position before the paper feed cassette 5 is mounted at the feedable 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. FIG. 7A is a diagram illustrating a state of the sheet feeding apparatus according to the present embodiment when the sheet feeding cassette 5 starts to be mounted, and FIG. 7B is a diagram illustrating the state of the sheet feeding apparatus. It is a figure which shows a state when the paper feed cassette 5 has reached the feedable position. In FIG. 7, the same reference numerals as those in FIG. 5 described above indicate the same or corresponding parts.

  In the present embodiment, as shown in FIG. 7, when the sheet is set in the sheet feeding cassette 5 in an area where the conveyance guide portion 71 of the sheet feeding cassette 5 is not provided, the restriction for regulating the leading edge of the sheet. A tip regulating member 13 as means is provided. The front end regulating member 13 is provided with a sheet feed with a pivot shaft 131 parallel to the mounting direction Y1 supported rotatably by a bearing 131a provided facing the outer side surface 6b of the downstream side plate 6 of the cassette body 5a. It is supported so as to be rotatable in the feeding direction. In FIG. 7, only one bearing 131a is shown.

  In addition, when the paper feed cassette 5 is pulled out from the cassette mounting space A of the printer main body 31A, the leading end regulating member 13 is urged by a biasing member such as a spring (not shown) and rotates upward. Abuts against a stopper (not shown). Then, by coming into contact with the stopper, as shown in FIG. Thus, when the sheet S is set in the sheet feeding cassette 5, the sheet S comes into contact with the leading end regulating member 13 moved to the regulating position, and does not protrude downstream in the sheet feeding direction.

  At the downstream end in the mounting direction of the tip regulating member 13, there is a contact surface twisted in the clockwise direction toward the mounting direction downstream side, and an abutting portion 13 a that can contact the contact member 9 is provided. Is provided. Accordingly, when the abutting portion 13a comes into contact with the abutting member 9 in the process of mounting the paper feeding cassette 5 on the printer main body 31A, the rotation shaft 131 rotates integrally with the abutting portion 13a. The tip regulating member 13 rotates downward against the urging force of the urging member. After that, the front end regulating member 10 becomes parallel to the outer surface 6b outside the sheet conveyance path as shown in FIG. 7B until the paper feed cassette 5 reaches the feedable position. Rotate to position.

  In the present embodiment, the downstream plate 6 is provided with a notch 6e. Thus, by providing the notch 6e, the abutting portion 13a rotating integrally with the rotating shaft 131 is prevented from interfering with the outer side 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 abut against the sheet stored in the cassette body 5a even when the abutting portion 13a enters the cassette body 5a when the leading end regulating member 13 is rotated downward. It is provided in a position where there is nothing.

  Thus, before the sheet feeding cassette 5 reaches the feedable position, the leading edge regulating member 13 is rotated downward and moved to the retracted position outside the sheet conveying path, so that the leading edge regulating member 13 is fed during sheet feeding. Can be prevented from interfering with sheet feeding. Note that when the contact with the contact member 9 is released when the front end regulating member 13 is pulled out of the printer main body 31A from the printer main body 31A, the front end restricting member 13 is rotated upward by the urging member, as shown in FIG. Return to the indicated restriction position.

  As described above, in the present embodiment, the tip restricting member 13 that can move to the restricting 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 conveyance guide portion 71. Further, before the paper feed cassette 5 is mounted at the feedable position, the front end regulating member 13 is brought into contact with the abutting member 9 to be moved from the regulated position to the retracted position.

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

DESCRIPTION OF SYMBOLS 1 ... Pick-up roller, 2 ... Feed roller, 3 ... Retard roller, 4 ... Sheet feeding part (sheet feeding means), 5 ... Paper feed cassette (sheet storage means), 5a ... Cassette main body, 6 ... Downstream plate, 6c DESCRIPTION OF SYMBOLS: Notch, 9 ... Contact member (actuating means), 10 ... Tip regulating member, 10a ... Restricting 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 main body (apparatus main body), 31B ... Image forming section, 31C ... Sheet feeding apparatus, 7 ... Conveying guide, 71 ... Conveying guide section ( 1st guide part), 71b ... contact surface (first restriction surface), 72 ... main body side conveyance guide part (second guide part), 72b ... contact surface (third restriction surface), 101 ... Rotating shaft, 102 ... (Biasing member), 131 ... rotation axis, A ... cassette mounting space, S ... Sheet

Claims (19)

The device body;
A sheet feeding means provided in the apparatus main body for feeding sheets;
A sheet storage means for storing a sheet fed by the sheet feeding means and mounted so as to be able to be pulled out in a mounting space of the apparatus main body;
A notch that is provided in the sheet storage means, and in which the sheet storage means is mounted in the mounting space;
In a state where the sheet storage unit is mounted in the mounting space, the sheet storage unit includes a regulation surface provided in the sheet storage unit and a regulation surface provided in the apparatus main body, and is stored in the sheet storage unit. A front end regulating surface capable of regulating the downstream end of the sheet,
A regulating member provided corresponding to the notch of the sheet storage means and movable between a first position where the downstream end of the stored sheet can be regulated and a second position where the sheet is not regulated;
An actuating means provided in the apparatus main body for moving the restricting member from the first position to the second position when the sheet storage means is mounted in the mounting space;
A sheet feeding apparatus comprising:   Biasing the biasing member from the second position to the first position to return the restraining member from the second position to the first position when the sheet storage means is pulled out of the mounting space. The sheet feeding apparatus according to claim 1, further comprising means.   3. The sheet feeding according to claim 1, wherein the restricting member has a restricting surface that forms the same surface as the restricting surface of the sheet storage unit and restricts the sheet from protruding at the notch. apparatus.   The restricting member is provided so as to be rotatable in a plane parallel to the mounting direction of the sheet storage means, and the actuating means abuts on the restricting member as the seat storage means moves in the mounting direction. The sheet feeding apparatus according to claim 1, wherein the regulating member is rotated.   The actuating means abuts on the regulating member and rotates downward with attachment of the sheet storage means to the apparatus main body, and then is positioned above the regulating member and moves the regulating member to the second position. The sheet feeding device according to claim 4, wherein the sheet feeding device is held by the sheet feeding device.   The restricting member is provided so as to be slidable in a plane parallel to the mounting direction of the sheet storage means, and the operating means abuts on the restricting member as the seat storage means moves in the mounting direction. The sheet feeding apparatus according to claim 1, wherein the regulating member is slid.   A slide guide provided in the sheet storage means and inclined so that a downstream side in the mounting direction of the sheet storage means is higher than an upstream side in the mounting direction, and the regulating member is slidably supported by the slide guide; The sheet feeding apparatus according to claim 6, wherein the sheet feeding apparatus is a sheet feeding apparatus.   The restricting member is supported so as to be rotatable in the sheet feeding direction by an axis parallel to the mounting direction of the sheet storage means, and the actuating means moves in the mounting direction of the sheet storage means. 4. The sheet feeding device according to claim 1, wherein the sheet feeding device contacts with the regulating member and rotates the regulating member in the sheet feeding direction. 5.   The restricting member has a contact surface twisted so as to rotate the restricting member downward as it goes downstream in the mounting direction, and the actuating means contacts the contact surface and The sheet feeding device according to claim 8, wherein the regulating member is rotated in the sheet feeding direction. A first guide portion for guiding a sheet, which is provided in the sheet storage means, and is arranged on the upstream side in the mounting direction with respect to the sheet feeding means when the sheet storage means is mounted in the mounting space; ,
A second guide part 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 part when the sheet storage means is mounted in the mounting space; With
10. The sheet feeding apparatus according to claim 1, wherein each of the first guide portion and the second guide portion is provided with a restriction surface that constitutes the leading edge restriction surface. 11. .   The mounting direction of the sheet storage unit is a direction orthogonal to a direction in which the sheet feeding unit feeds a sheet from the sheet storage unit. Sheet feeding device. A sheet storage means that is mounted so as to be drawable in the mounting space of the apparatus main body in a direction orthogonal to the sheet feeding direction,
The sheet storage unit is supported by a shaft in a cantilevered state, and is disposed 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 mounted in the mounting space. A pair of separation rollers for separating sheets fed from the means;
A first restriction surface provided in the sheet storage means, located upstream of the center of the sheet storage means in the mounting direction of the sheet storage means and capable of restricting the leading edge of the stored sheet;
The sheet storage means is located downstream of the center of the sheet storage means and is supported by the sheet storage means movably between a restriction position where the leading edge of the stored sheet can be restricted and a retreat position where it is not restricted, and the sheet storage means A regulating member having a second regulating surface capable of regulating the leading edge of the stored sheet at the regulating position in a state where the means is pulled out from the mounting space;
When the sheet storage means is provided in the apparatus main body and is mounted in the mounting space, the sheet storage means is positioned downstream of the center of the sheet storage means in the mounting direction of the sheet storage means and A third regulating surface that regulates the tip;
A sheet feeding apparatus comprising:   The sheet feeding device according to claim 12, further comprising a sheet feeding frame that supports the pair of separation rollers, wherein the regulation member having the third regulating surface is provided on the sheet feeding frame.   A notch for 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 12 or 13.   15. The apparatus body according to claim 12, further comprising operating means for moving the restricting member from the restricting position to the retracted position as the sheet storage means is attached to the attachment space. The sheet feeding apparatus according to claim 1.   The restricting member is supported so as to be movable between the restricting position and the retracted position by rotating, and the restricting position is set by the actuating means in accordance with the operation of mounting the sheet storage means in the attachment space. The sheet feeding device according to claim 15, wherein the sheet feeding device is rotated to the retracted position.   The restricting member is slidably supported so as to be movable between the restricting position and the retracted position, and the actuating means moves the restricting position by the actuating means when the sheet storage means is attached to the attachment space. The sheet feeding device according to claim 15, wherein the sheet feeding device is slid to the retracted position.   The restricting member is supported so as to be movable between the restricting position and the retracted position by an axis parallel to the mounting direction of the sheet storing means, and the sheet storing means is mounted in the mounting space. Accordingly, the sheet feeding device according to claim 15, wherein the sheet feeding device is rotated from the restricted position to the retracted position by the operating means.   An image forming apparatus comprising: an image forming unit; and a sheet feeding device according to claim 1 that feeds a sheet toward the image forming unit.

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