JP4650326B2 - Sheet supply apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet supply apparatus and an image forming apparatus, and more specifically, a sheet supply apparatus that lifts up a sheet-like recording medium such as paper stacked on a stacking plate to a position where it can be fed, and the sheet The present invention relates to an image forming apparatus in which an image forming unit forms an image on a sheet-like recording medium supplied from a supply apparatus.

  In a paper feeding device that is mounted on an image forming apparatus and supplies paper to an image forming unit, the paper loaded on the stacking plate is placed in the frame of the paper feeding device in order to abut on paper feeding means such as a paper feeding roll. 2. Description of the Related Art A configuration in which a stacking plate that can be moved up and down is lifted up with a cable is widely used.

  For example, in the conventional paper feeding unit 200 shown in FIG. 11, a bottom plate 210 serving as a stacking plate on which the paper P is stacked is disposed in a frame 201 in which the paper P is stored. 210, convex portions 212A, 212B, 212C, and 212D provided on the front edge and the rear edge are inserted into guide holes 214A, 214B, 214C, and 214D formed in the front frame 202 and the rear frame 204 of the frame 201, By being pulled up by the cables 216A, 216B, 216C, and 216D that are connected and fixed to the respective convex portions 212, the respective convex portions 212 are lifted up while being guided by the respective guide holes 214, and are raised to a position where the paper P can be fed. . In the case of the bottom plate 210, a gap is provided between each convex portion 212 and each guide hole 214, and the left edge abuts on the left side frame 206, thereby positioning in the feeding direction (arrow X direction). In this state, the front edge comes into contact with the front frame 202 to perform positioning in a direction substantially perpendicular to the feeding direction (arrow Y direction), and in this state, between the right edge of the bottom plate 210 and the right side frame 208. Is provided with a gap XR, and a gap YR is provided between the rear edge and the rear frame 204.

Further, in such a lifting type paper feeding device, the stacking plate is built in the paper storage cassette, and the paper storage cassette is detachably supported with respect to the paper feeding unit, so that the stacking plate can be exchanged. There is an improved technique (for example, see Patent Document 1).
Japanese Utility Model Publication No. 61-8646

  However, in the conventional paper feed unit 200, the bottom plate 210 that slides up and down in the frame 201 causes the traces of the front frame 202 and the left side frame 206 to slide and cause sliding contact, and the paper feed unit 200 is recycled. Sometimes the need to paint or replace.

  Similarly, in the configuration of Patent Document 1, since a loading plate that slides up and down in the cassette causes a slide mark and a sliding contact on the inner wall surface of the cassette, it is necessary to paint or replace when the paper feeding device is recycled. Recyclability is bad. In addition, the double structure of the paper storage cassette and the paper feed unit is complicated and expensive.

  In view of the above-described facts, an object of the present invention is to provide a sheet feeding device and an image forming apparatus that have a simple configuration and can be manufactured at low cost and have good recyclability.

In order to achieve the above object, the invention according to claim 1 is a housing in which sheets are stored, a stacking plate provided in the casing so as to be movable up and down, and on which the sheets are stacked, and an opposite of the housing. Provided on both side wall portions, and a guide portion for guiding raising and lowering of the stacking plate, and a convex portion provided on both end portions of the stacking plate and slidably fitted in the guide portion. And a wire rod that is connected to both side ends of the stacking plate and lifts the stacking plate, and the stacking plate is raised to a position where the sheet can be fed by winding the wire rod, and the wire rod is sent out. Elevating means for lowering the stacking plate by means of, and a positioning portion provided in the guide portion, the projecting portion being slidably contacted with the housing so that the stacking plate is positioned with a gap therebetween , as well as have the said positioning A first portion for positioning the sheet feeding direction of the stacking plate by the contact of the convex portion formed by the side wall portions being bent at right angles toward the outside of the housing by the guide portions; And a second portion for positioning a direction orthogonal to the sheet feeding direction by contact of the convex portion, which is formed by being bent at a right angle so that the tip of the positioning portion is parallel to the both side wall portions. It is characterized by providing the positioning part .

  In the present invention, the stacking plate provided in the casing in which the sheet is accommodated can be moved up and down, the wire connected to the both ends is wound up by the lifting means, and the protrusions provided at the both ends are the casing. By lifting up while being guided by the guide portions provided on the opposite side walls of the body, the stacked sheets are raised to a position where they can be fed. The sheet comes into contact with a feeding means such as a rotating roll and is fed by driving the feeding means. Further, when the wire rod is sent out from the elevating means, the stacking plate is lifted down while the convex portion is guided by the guide portion, and lowered to a position where the sheets can be stacked and replenished.

  In this way, the stacking plate that moves up and down in the housing is positioned with a gap with respect to the housing, with the convex portion slidably contacting the positioning portion provided in the guide portion of the housing, In the ascending / descending operation guided by the guide portion, only the convex portion slides on the positioning portion, and the stacking plate main body slides without sliding on the casing. As a result, the inner wall surface of the housing is not subjected to slide marks or sliding contact by the loading plate, and the frequency of painting or replacement performed when recycling the paper feeding device can be reduced, and the recyclability is improved. In addition, since the housing that houses the loading plate has a single structure, the configuration is simplified and the housing can be manufactured at low cost.

  According to a second aspect of the present invention, in the sheet supply apparatus according to the first aspect, the wire is connected to the convex portion.

  In the present invention, the wire rod is connected to the convex portions provided on both side end portions of the stacking plate so that the force for raising and lowering the stacking plate directly acts on the convex portion guided by the guide portion of the housing. Sliding resistance generated between the guide portion and the guide portion (positioning portion) can be reduced, and the stability of the lifting operation can be improved.

If it adds about the invention of Claim 1 , since a convex part slides with respect to the positioning part of a guide part by the raising / lowering operation | movement of a loading board, a sliding contact will generate | occur | produce in the contact part of a positioning part and a convex part. However, by disposing the positioning portion on the outer surface side of the casing, a positioning section and a sliding contact are not visible or difficult to visually recognize from a user who normally looks only within the casing that stores the sheet. Thereby, the frequency of the coating and replacement | exchange performed at the time of recycling can be reduced by attaching this sliding contact.

In addition , the first and second positioning portions are provided in the positioning portion with which the convex portion abuts, the first positioning portion positions the sheet feeding direction of the stacking plate, The positioning unit positions the direction substantially orthogonal to the sheet feeding direction. Thus, by positioning the stacking plate in the sheet feeding direction and two directions (XY directions) substantially orthogonal to the sheet feeding direction, the sheet feeding direction of the sheets stacked on the stacking plate and the position in the substantially orthogonal direction are positioned. Therefore, it is possible to prevent a sheet feeding failure or the like caused by the variation in the position.

  In addition, by dividing the positioning part, it is possible to further reduce the sliding resistance generated between the convex part and the positioning part, and it is possible to reliably prevent the occurrence of galling and rattling, and to further raise and lower the loading plate. Can be stabilized. Further, the occurrence of sliding contact is dispersed and the damage per location is reduced, so that the sliding contact becomes inconspicuous and can contribute to the reduction of painting / replacement frequency.

According to a third aspect of the present invention, an image forming apparatus includes the sheet supply device according to the first or second aspect, and an image is formed on the sheet-like recording medium supplied from the paper supply device by the image forming unit. It is characterized by forming.

  If it is an image forming apparatus provided with the above-mentioned sheet feeding device, the aesthetic appearance is not impaired even in long-term use, because the casing of the sheet supply device that stores the sheet-like recording medium is not damaged. The lifting and lowering operation of the loading plate is stable, and the recording medium is fed well. Further, the cost of the entire apparatus can be reduced by reducing the cost of the sheet feeding apparatus and improving the recyclability.

  According to the sheet feeding device and the image forming apparatus of the present invention, the configuration is simple and can be manufactured at low cost, and the recyclability is improved.

  Hereinafter, a sheet feeding apparatus (sheet feeding unit) to which a sheet feeding apparatus according to an embodiment of the present invention is applied and an image forming apparatus equipped with the sheet feeding apparatus will be described with reference to the drawings.

  An image forming apparatus 10 according to this embodiment shown in FIG. 1 is a copying machine using an electrophotographic system. As shown in the drawing, a document placed on a document tray is imaged on the upper surface of an image forming apparatus main body 12. An automatic document feeder 14 is provided that automatically feeds the document to the reading position and automatically ejects it after reading the image.

  Inside the image forming apparatus main body 12, a document reading unit 16 that reads an image of a document sent from the automatic document feeder 14 and converts it into an image signal, and an image (paper) based on the image signal from the document reading unit 16. An image forming unit 18 that forms a toner image), a paper feeding mechanism 20 that supplies paper to the image forming unit 18, and a paper aligning device 80 that corrects bending in the transport direction of the paper supplied to the image forming unit 18. Is provided.

  As shown in FIG. 2, the paper feed mechanism 20 has two small paper feed units 22A, 22B, A3 size and other large size paper PL that accommodate small size paper PS such as A4 size and letter size that are frequently used. Large paper feeding units 24A, 24B, and feeding units 26A, 26B, 26C, 26D for feeding paper P (PS, PL) from these paper feeding units 22A, 22B, 24A, 24B. A paper transport path 28 for guiding the paper P to the image forming section 18 and a plurality of transport roll pairs 30 for transporting the paper to the image forming section 18 side along the paper transport path 28 are provided.

  The small paper feed units 22A and 22B are accommodated in a state where a large amount (for example, 1500 sheets) of small-size paper PS is stacked. Each of the paper feed units 22A in the substantially horizontal direction and adjacent to the upstream side and the downstream side in the paper feeding direction are arranged in parallel, and the upstream side (right side in FIG. 2) is closer to the downstream side (left side in FIG. 2). ) Are disposed slightly above the sheet feeding unit 22B.

  Inside the paper feed units 22A and 22B, there is provided a bottom plate 110 which is driven by a motor (not shown) and which can be moved in the vertical direction by an elevating mechanism which will be described in detail later. The paper is stacked on the bottom plate 110 and accommodated in the paper feeding units 22A and 22B.

  Further, the large paper feeding units 24A and 24B are arranged in a substantially two-tiered manner above the paper feeding units 22A and 22B arranged in parallel, and are accommodated in a state where the large-size papers PL are stacked.

  The feeding units 26 (26A to 26D) provided corresponding to the sheet feeding units 22A, 22B, 24A, and 24B have the same configuration and share the components. The feeding unit 26 includes a nudger roll (feeding roll) 34 for feeding the uppermost sheet P in the sheet feeding unit in the sheet feeding direction, and a feed for separating and feeding the fed sheets P one by one. Although not shown, the roll 36 and the retard roll 38, a support mechanism that rotatably supports each of the rolls, a motor as a drive source that rotationally drives each roll, and a rotational force that transmits the rotational force of the motor to each roll A transmission mechanism and the like are provided, and each of these components is housed in the frame 40.

  Above the sheet feeding mechanism 20, a sheet aligning device 80 is connected to the downstream end (upper end) of the sheet conveying path 28, and the sheet P is fed into the sheet aligning apparatus 80 from the sheet conveying path 28. It is.

  The sheet aligning device 80 includes a sheet conveying path 82 that connects between the sheet conveying path 28 on the paper feeding mechanism 20 side and the image forming unit 18, and a pair of conveying rolls (auxiliary rolls) disposed on the upstream side of the sheet conveying path 82. ) 84 and a pair of resist rolls (correction rolls) 86 disposed on the downstream side, although not shown, a support mechanism that rotatably supports each of these rolls, a motor as a drive source that rotationally drives each roll, and A rotational force transmission mechanism that transmits the rotational force of the motor to each roll is provided, and the paper P is transported to the downstream side by the rotation of the transport roll 84, and a loop is formed by abutting the front end of the paper against the stopped resist roll 86. Thus, the bending of the paper P with respect to the transport direction is corrected (loop aligning). Then, the registration roll 86 and the transport roll 84 are rotated at a predetermined timing (image formation timing) after the bending correction, and the paper P is fed into the image forming unit 18.

  Further, the paper transport system of the image forming apparatus 10 transports the paper P with a substantially central reference in the width direction of the paper transport paths 28 and 82, that is, in a state where the approximate center in the paper width direction is aligned with the approximate center. It is a center cash register method for transporting.

  The image forming apparatus 10 has the above-described configuration. In the image forming apparatus 10, an image of a document sent from the automatic document feeder 14 is converted into a read image signal by the document reading unit 16, and the image signal is converted into the image signal. On the basis of the image forming unit 18, the paper is fed from the paper feeding units 22 A, 22 B, 24 A, and 24 B by the feeding units 26 A, 26 B, 26 C, and 26 D, and is transported through the paper transport path 28 by the transport roller pair 30. An image of the original is copied onto the paper P by forming an image on the supplied paper P with the bending in the conveyance direction corrected.

  Next, a sheet feeding device (sheet supply device) according to an embodiment of the present invention will be described using the above-described sheet feeding unit 22 (22A, 22B) as an example. The paper feed unit 22 of this embodiment is attached to the image forming apparatus main body 12 so as to be slidable in a direction (arrow Y direction) substantially perpendicular to the paper P feeding direction (arrow X direction). In the following description of the paper feeding unit 22, the side from which the paper feeding unit is pulled out from the image forming apparatus main body 12 is the front side (front side), the side to be pushed in is the back side (rear side), and the side on which the paper P is fed Is the left side and the opposite side is the right side.

  As shown in FIGS. 3 to 7, the paper feed unit 22 of the present embodiment includes a case-like frame 100 that is open on the upper surface side that constitutes the main body of the unit. The frame 100 includes a base frame 101 having a rectangular shape in plan view, and a front frame 102, a rear frame 104, a left side frame 106, and a right side frame 108 are erected on each edge portion of the upper surface of the base frame 101. Configured. A peripheral wall is formed on the base frame 101 by these four frames, and the inside thereof serves as a storage space for storing the paper P.

  Inside the frame 100, a bottom plate 110 on which the stored paper P is stacked is provided on the base frame 101 substantially in parallel with the base frame 101. Further, the positioning of the paper P stacked on the bottom plate 110 is performed. A pair of side guides 112 </ b> A and 112 </ b> B are arranged apart from each other in the front-rear direction.

  As shown in FIG. 5, a pair of racks 114 </ b> A and 114 </ b> B are provided on the lower surface side of the base frame 101 so as to extend toward the center of the base frame 101 along the front-rear direction. The racks 114A and 114B are arranged with the rack surfaces facing each other and meshed with the pinion gear 116, fixed to the lower ends of the corresponding side guides 112A and 112B by screws 118, and front and rear together with the side guides 112A and 112B. It is attached to the base frame 101 so as to slide in the direction. As a result, when the user slides one side guide 112A disposed, for example, on the front side in the frame 100, the other side guide 112B slides in the reverse direction in conjunction with this, and the guide interval can be adjusted. . Then, by adjusting the interval between the side guides 112A and 112B in advance to the width of the paper P stored in the paper feeding unit 22, the side edges of the paper P stacked on the bottom plate 110 are side guides 112A and 112B. And the stacking position in the paper width direction is regulated.

  On the other hand, the bottom plate 110 according to the present embodiment is attached to the frame 100 so as to move up and down along the vertical direction. As shown in FIGS. Is provided with a substantially rectangular plate body 120. Openings 122A and 122B of a size that allows the side guides 112A and 112B to be inserted and slid in the front-rear direction are formed at the front and rear positions corresponding to the side guides 112A and 112B of the plate body 120, respectively. The side guides 112A and 112B are inserted through the openings 122A and 122B and protrude above the plate body 120 (see FIG. 4).

  Two convex portions 124A and 124B are provided at a predetermined interval on the front edge portion of the plate body 120, and two convex portions 124C and 124D are also provided at a predetermined interval on the rear edge portion.

  Of the four convex portions 124A to 124D provided on the plate body 120, the convex portion 124A on the right side of the front edge and the convex portion 124C on the right side of the rear edge are substantially L-shaped in plan view, and are convex on the left side of the front edge. The portion 124B and the convex portion 124D on the left side of the rear edge are substantially rectangular in a plan view, and each has a cable fixing hole 126 formed therethrough. In addition, the bottom plate 110 has a reference in the feeding direction (arrow X direction) of the paper P with respect to the frame 100, the left edge 125AX of the corner 125A provided at the base end on the left side of the convex portion 124A, and the convex portion. The left edge 125CX of the corner portion 125C provided at the base end portion on the left side of 124C, and the reference in the front-rear direction (sliding direction of the paper feeding unit 22 / arrow Y direction) with respect to the frame 100 is the convex portion 124A. It is comprised by the front edge 125AY of the corner | angular part 125A.

  On the other hand, in the frame 100 of this embodiment, as shown in FIGS. 6, 7, 9, and 10, guide holes 130 </ b> A and 130 </ b> B into which the convex portions 124 </ b> A and 124 </ b> B of the bottom plate 110 are inserted into the front frame 102. Are formed in the rear frame 104, and guide holes 130C and 130D into which the convex portions 124C and 124D of the bottom plate 110 are inserted are formed. The four guide holes 130A to 130D in total are formed in a vertically long rectangular shape extending in the vertical direction (see FIGS. 6 and 7), and on the left and right edges, the outer sides of the frames. A bent portion 132 that is bent (front side or rear side) is provided.

  Of the total eight bent portions 132, as shown in FIGS. 9 and 10A to 10D, the left bent portion 132AL of the guide hole 130A corresponding to the corner 125A of the convex portion 124A, The left bent portion 132CL of the guide hole 130C corresponding to the corner portion 125C of the portion 124C is substantially L-shaped, the right bent portion 132AR of the guide hole 130A, the left and right bent portions 132BR and 132BL of the guide hole 130B, and the guide hole 130C. The right bent portion 132CR and the left and right bent portions 132DR and 132DL of the guide hole 130D are formed substantially at right angles to the respective frames.

  Further, the left edge 125AX and the front edge 125AY of the corner portion 125A of the convex portion 124A are slidably in contact with the inner peripheral surface of the one bent portion 132AL that is substantially L-shaped (FIG. 10A). The left edge 125CX of the corner portion 125C of the convex portion 124C is slidably in contact with the inner peripheral surface of the other bent portion 132CL (see FIG. 10C), and the remaining bent portions 132AR, In 132BR, 132BL, 132CR, 132DR, and 132DL, gaps are provided between the convex portions 124A to 124D (see FIGS. 10A to 10D).

  Here, the left edge 125AX of the corner portion 125A of the convex portion 124A abuts on the bent portion 132AL of the guide hole 130A, and the left edge 125CX of the corner portion 125C of the convex portion 124C abuts on the bent portion 132CL of the guide hole 130C. Thus, the bottom plate 110 is positioned relative to the frame 100 in the X direction (paper P feeding direction). In this state, the bottom plate 110 is positioned between the left edge of the bottom plate 110 and the left side frame 106 and the right edge of the bottom plate 110. And the right side frame 108 are provided with predetermined gaps XL and XR, respectively.

  Further, the front edge 125AY of the corner portion 125A of the convex portion 124A abuts on the bent portion 132AL of the guide hole 130A, thereby positioning the bottom plate 110 with respect to the frame 100 in the Y direction (front-rear direction / sliding direction of the paper feed unit 22). In this state, predetermined gaps YF and YR are provided between the front edge of the bottom plate 110 and the front frame 102 and between the rear edge of the bottom plate 110 and the rear frame 104, respectively.

  As described above, the convex portions 124A to 124D are inserted into the guide holes 130A to 130D of the frame 100, and the corner portions 125A and 125C of the convex portions 124A and 124C abut against the bent portions 132AL and 132CL, thereby As shown in FIGS. 6 and 7, in the bottom plate 110 where the position in the Y direction is determined, the end portions of the cables 134A, 134B, 134C, and 134D are inserted into the cable fixing holes 126 of the convex portions 124A to 124D from above. The four cables 134A to 134D are wound around pulleys 136A, 136B, 136C, and 136D that are attached to the upper sides of the guide holes 130A to 130D on the outer side surfaces of the front frame 102 and the rear frame 104, respectively. It is suspended by that.

  As shown in FIG. 6, on the front frame 102 side, the cable 134A wound around the pulley 136A is drawn around the left side and wound around the pulley 136B, and the cable 134A and the cable 134B are both outside the left side frame 106. It is wound around a winding part 142AB of a lift shaft 140 provided at the lower part of the side surface. As shown in FIG. 7, on the rear frame 104 side, the cable 134C wound around the pulley 136C and the cable 134D wound around the pulley 136D are both provided between the guide hole 130C and the guide hole 130D. It is wound around the winding portion 142CD of the lift shaft 140 via the relay pulley 138. As shown in FIGS. 3 and 4, a coupling 144 is attached to the rear end portion of the lift shaft 140.

  In the sheet feeding unit 22 of the present embodiment, the lifting mechanism for lifting the bottom plate 110 includes a lift shaft 140 that winds the cables 134A to 134D, pulleys 136A to 136D around which the cables 134A to 134D are wound, and a relay. When the sheet feeding unit 22 is inserted into the image forming apparatus main body 12, the coupling 144 is connected to a drive source (not shown), and the cable 134A is connected from the drive source to the lift shaft 140 via the coupling 144. The rotational driving force is transmitted in the direction of winding up to 134D. As a result, the cables 134A to 134D are wound around the winding portions 142AB and 142CD of the lift shaft 140, and the bottom plate 110 is connected to the cables 134A to 134D while the convex portions 124A to 124D are guided by the guide holes 130A to 130D of the frame 100. The sheet P is pulled up and moved up to a position where the sheet P can be fed, that is, to a position where the sheet P contacts the nudger roll 34 (see FIG. 2). Further, when the paper feeding unit 22 is pulled out from the image forming apparatus main body 12, the connection between the drive source and the coupling 144 is released, the lift shaft 140 is rotatable, the bottom plate 110 is lowered by its own weight, and the lift is thereby lifted. The shaft 140 rotates in the direction of feeding out the cables 134A to 134D.

  With the above configuration, in the paper feeding unit 22 of the present embodiment, the paper P is pulled out from the image forming apparatus main body 12 and stored on the bottom plate 110 in the frame 100, and is pushed into the image forming apparatus main body 12. When set, the bottom plate 110 has the cables 134A to 134D connected to the convex portions 124A to 124D wound around the lift shaft 140 that is rotationally driven by the drive source, and the convex portions 124A to 124D are guided by the guide holes 130A of the frame 100. The sheet is lifted up while being guided by .about.130D, and rises to a feedable position where the loaded paper P contacts the nudger roll 34. When the nudger roll 34 is rotationally driven during image formation, the paper P is fed by the nudger roll 34.

  Further, when the paper feeding unit 22 is pulled out from the image forming apparatus main body 12, the cables 134A to 134D can be sent out from the rotatable lift shaft 140, and the convex portions 124A to 124D of the bottom plate 110 have guide holes 130A to 130A. It is lifted down by its own weight while being guided by 130D, and lowered to a position where the paper P can be loaded and replenished.

  As described above, the bottom plate 110 that moves up and down in the frame 100 of the paper feeding unit 22 has the bent portion 132AL provided in the guide hole 130A of the frame 100 and the corner portion 125A (the left edge 125AX and the front edge 125AY) of the convex portion 124A. ) So that the corner portion 125C (left edge 125CX) of the convex portion 124C is slidably contacted with the bent portion 132CL provided in the guide hole 130C, so that the gap XL, XR, YF, and YR are positioned, and only the corner portions 125A and 125C are in sliding contact with the bent portions 132AL and 132CL, and the plate main body 120 is slid without sliding on the frame 100. As a result, the inner wall surface of the frame 100 is not slid or damaged by the bottom plate 110, and the frequency of painting and replacement performed when the paper supply unit 22 is recycled can be reduced, resulting in good recyclability. . In addition, since the frame 100 that houses the bottom plate 110 has a single structure, the configuration is simplified and the frame 100 can be manufactured at low cost.

  Further, in the present embodiment, the cables 134A to 134D are connected to the convex portions 124A to 124D provided on both side end portions (front edge and rear edge) of the bottom plate 110, so that the force for moving the bottom plate 110 up and down is obtained. The projections 124A to 124D guided by the guide holes 130A to 130D of the frame 100 directly act. Thereby, the sliding resistance generated between the corner portion 125A and the bent portion 132AL and the sliding resistance generated between the corner portion 125C and the bent portion 132CL can be reduced, and the stability of the lifting operation is improved.

  In this embodiment, since the corners 125A and 125C slide with respect to the bent portions 132AL and 132CL by the raising and lowering operation of the bottom plate 110, the contact portions between the bent portions 132AL and 132CL and the corner portions 125A and 125C are in sliding contact. Although the scratches are generated, the bent portions 132AL and 132CL are arranged on the outer surface side of the front frame 102 and the rear frame 104, so that the bent portion is usually viewed only from the inside of the frame 100 storing the paper P. 132AL, 132CL and sliding contact are not visible or difficult to see. Thereby, the frequency of the coating and replacement | exchange performed at the time of recycling can be reduced by attaching this sliding contact.

  In the present embodiment, the left edge 125AX of the corner portion 125A is brought into contact with the bent portion 132AL, and the left edge 125CX of the corner portion 125C is brought into contact with the bent portion 132CL. By positioning the feeding direction (X direction) and bringing the front edge 125AY of the corner portion 125A into contact with the bent portion 132AL, the direction substantially perpendicular to the paper feeding direction (Y direction / sliding direction of the paper feeding unit 22) Thus, by positioning the bottom plate 110 in two directions (XY directions), the feeding direction of the paper P stacked on the bottom plate 110 and the position in the substantially orthogonal direction are constant. Accordingly, it is possible to prevent a paper feeding failure or the like caused by the variation in the position.

  In addition, by dividing the positioning portion as described above, it is possible to further reduce the sliding resistance generated between the corner portion and the bent portion, and it is possible to reliably prevent the occurrence of galling and rattling. The raising / lowering operation of the plate 110 can be further stabilized. Further, the occurrence of sliding contact is dispersed and the damage per location is reduced, so that the sliding contact becomes inconspicuous and can contribute to the reduction of painting / replacement frequency.

  In the image forming apparatus 10 of the present embodiment provided with the paper feeding unit 22 described above, the frame 100 of the paper feeding unit 22 that stores the paper P is not damaged, and the aesthetics are impaired even during long-term use. In addition, the raising / lowering operation of the bottom plate 110 is stable, and the paper P is fed well. Furthermore, the cost of the entire apparatus can be reduced by reducing the cost of the paper feed unit 22 and improving the recyclability.

  As mentioned above, although this invention was demonstrated in detail by the specific embodiment mentioned above, this invention is not limited to it, Various other forms can be implemented within the scope of the present invention.

  For example, in the above-described embodiment, the paper conveyance system has been described in the case of the center registration method in which the paper P is conveyed with a substantially central reference in the width direction of the paper conveyance paths 28 and 82. For example, the present invention can also be applied to a side registration system that transports a sheet on the basis of the side edge in the width direction of the sheet transport path.

  The present invention is not limited to the above-described copying machine, but can be applied to other image forming apparatuses such as a laser printer and an ink jet printer, and a paper feeding apparatus mounted on these printers. Furthermore, the present invention is not limited to the above-described sheet feeding device that supplies a sheet-like recording medium, but can also be applied to a sheet feeding device used for feeding for processing a sheet such as a polymer film. it can.

1 is a configuration diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a configuration diagram illustrating a schematic configuration of a sheet feeding device mounted on the image forming apparatus of FIG. 1. It is a top view which shows the paper feed unit which concerns on one Embodiment of this invention. It is a left view which shows the paper feed unit which concerns on one Embodiment of this invention. It is a bottom view which shows the paper feed unit which concerns on one Embodiment of this invention. It is a front view which shows the paper feed unit which concerns on one Embodiment of this invention. It is a rear view which shows the paper feed unit which concerns on one Embodiment of this invention. (A) which shows the bottom plate which concerns on one Embodiment of this invention is a top view, (B) is a left view. It is a top view which shows the principal part of the paper feed unit which concerns on one Embodiment of this invention. (A)-(D) are the enlarged plan views which expand and show the principal part of the paper feeding unit which concerns on one Embodiment of this invention. It is a top view which shows the principal part of the conventional paper feed unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 18 Image forming part 20 Paper feed mechanism 22 Paper feed unit (sheet supply apparatus)
22A paper feed unit (sheet supply device)
22B Paper feed unit (sheet supply device)
100 frames (housing)
101 Base frame 102 Front frame (side wall)
104 Rear frame (side wall)
106 Left side frame 108 Right side frame 110 Bottom plate (loading plate)
124A Convex part 124B Convex part 124C Convex part 124D Convex part 125A Corner part 125AX Left edge 125AY Front edge 125C Corner part 125CX Left edge 130A Guide hole (guide part)
130B Guide hole (guide part)
130C Guide hole (guide part)
130D guide hole (guide part)
132AL bent part (positioning part / first positioning part / second positioning part)
132CL bent part (positioning part / first positioning part)
134A cable (wire)
134B cable (wire)
134C cable (wire)
134D cable (wire)
136A Pulley (lifting / lowering means)
136B Pulley (lifting means)
136C Pulley (lifting means)
136D Pulley (lifting / lowering means)
138 Relay pulley (lifting means)
140 Lift shaft (lifting means)
142AB Winding part 142CD Winding part 144 Coupling P Paper (sheet / recording medium)

Claims (3)

A housing for storing sheets;
A loading plate provided in the casing so as to be movable up and down, on which the sheet is stacked;
Guide portions provided on opposite side wall portions of the housing, for guiding the lifting and lowering of the stacking plate,
Protruding portions that are provided at both end portions of the stacking plate and are slidably inserted into the guide portions and guided.
Wires connected to both ends of the loading plate, for lifting the loading plate,
Lifting means for raising the stacking plate to a position where the sheet can be fed by winding the wire, and lowering the stacking plate by sending out the wire;
A positioning portion provided on the guide portion, the positioning portion being slidably abutted so that the stacking plate is positioned with a gap with respect to the housing;
While Yes, said positioning portion, said side wall portions are formed by being bent at right angles toward the outside of the housing by the guide portion, sheet of the loading plate by the abutment of the convex portion A first positioning portion for positioning the feeding direction, and further bent at a right angle so that the tip thereof is parallel to the both side wall portions, and perpendicular to the sheet feeding direction by the contact of the convex portion. A sheet feeding apparatus comprising: a second positioning unit that positions a direction to be performed.   The sheet feeding apparatus according to claim 1, wherein the wire is connected to the convex portion. An image forming apparatus comprising: the sheet supply apparatus according to claim 1, wherein an image forming unit forms an image on a sheet-like recording medium supplied from the sheet supply apparatus.

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