Patent Publication Number: US-11661293-B2

Title: Sheet storage apparatus and image forming apparatus

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to a sheet storage apparatus storing a sheet and an image forming apparatus including this sheet storage apparatus. 
     Description of the Related Art 
     Generally, an image forming apparatus such as a printer includes a cassette capable of storing a sheet in a lower part of the apparatus, and forms an image on the sheet fed from the cassette. The cassette is disposed in such a manner that is capable of attaching to and drawing out from an apparatus body, and a pair of cursors regulating positions of side edges of a stored sheet are movably disposed in the cassette. 
     Hitherto, an image forming apparatus in which a groove is formed in a front side wall of a cassette body and a protrusion is disposed on each of the cursors is suggested (refer to Japanese Patent Laid-Open No. 2006-89151). When the cassette is attached to the apparatus body, a mobile carriage supporting the pair of cursors moves, and the protrusions disposed on the pair of cursors engage with the groove in the front side wall of the cassette body. Herewith, the intensity of the pair of cursors with respect to the external force in a width direction is increased, and, even if the cassette is thrusted into the apparatus body, the cursor is able to withstand such an impact. 
     However, since a linking mechanism to move the mobile carriage in conjunction with an attachment and a detachment of the cassette is necessary for the image forming apparatus described in Japanese Patent Laid-Open No. 2006-89151 mentioned above, a number of components and assembling man-hours are increased. Therefore, cost is increased. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the present invention, a sheet storage apparatus attached to an apparatus body in an attaching direction includes a sheet storage portion configured to store a sheet, a moving unit movably supported by the sheet storage portion in a moving direction parallel to the attaching direction, wherein the moving unit includes a regulation member and an extending member extending in the moving direction, the regulation member including a regulation surface regulating a position, in the moving direction, of the sheet stored in the sheet storage portion, and a first bonding surface extending along the moving direction, the extending member including a second bonding surface extending parallel to the first bonding surface, and wherein the first bonding surface and the second bonding surface are configured to be bonded to each other by adhesive. 
     According to a second aspect of the present invention, a sheet storage apparatus attached to an apparatus body in an attaching direction includes a sheet storage portion configured to store a sheet, a moving unit movably supported by the sheet storage portion in a moving direction parallel to the attaching direction, wherein the moving unit includes a regulation member and an extending member extending in the moving direction, the regulation member including a regulation surface regulating a position, in the moving direction, of the sheet stored in the sheet storage portion, and a first bonding surface extending along the moving direction, the extending member including a second bonding surface extending parallel to the first bonding surface, and wherein the first bonding surface and the second bonding surface are configured to be bonded to each other by double-sided tape. 
     According to a third aspect of the present invention, a sheet storage apparatus attached to an apparatus body in an attaching direction includes a sheet storage portion configured to store a sheet, and a moving unit movably supported by the sheet storage portion in a moving direction parallel to the attaching direction, wherein the moving unit includes a regulation member and an extending member extending in the moving direction, the regulation member including a regulation surface regulating a position, in the moving direction, of the sheet stored in the sheet storage portion and a first bonding surface extending along the moving direction, the extending member including a second bonding surface extending parallel to the first bonding surface, and wherein the first bonding surface and the second bonding surface are configured to be bonded to each other without being fastened by a fastening member. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic view showing a general arrangement of a printer relating to a first embodiment. 
         FIG.  2    is a perspective view showing a state where a cassette has been drawn out from an apparatus body. 
         FIG.  3    is a perspective view showing a sheet storage apparatus. 
         FIG.  4    is a perspective view showing a pair of side regulation plates. 
         FIG.  5    is a perspective view showing a detailed configuration of a bonding portion of a regulation member. 
         FIG.  6    is a perspective view showing a detailed configuration of a bonding portion of a rack member. 
         FIG.  7 A  is a perspective view showing the regulation member on which an adhesive has been coated. 
         FIG.  7 B  is a perspective view showing a state where the rack member is being inserted into the regulation member. 
         FIG.  8 A  is a perspective view showing a state where a hook portion is inserted into a rectangular hole. 
         FIG.  8 B  is a perspective view showing a state where the rack member has been slid with respect to the regulation member. 
         FIG.  9 A  is a cross-sectional view showing a state where a sheet is being replenished to the cassette. 
         FIG.  9 B  is a cross-sectional view showing a state where the cassette is being attached to the apparatus body. 
         FIG.  9 C  is a cross-sectional view showing a state where the regulation member has abutted on the cassette body. 
         FIG.  10    is a perspective view showing a detailed configuration of a bonding portion of a regulation member relating to a second embodiment. 
         FIG.  11    is a perspective view showing a detailed configuration of a bonding portion of a rack member. 
         FIG.  12 A  is a perspective view showing a state where a double-sided tape is sticked onto the regulation member. 
         FIG.  12 B  is a perspective view showing a state where the rack member is being inserted into the regulation member. 
         FIG.  12 C  is a perspective view showing a state where a boss portion has been engaged with a positioning hole. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     First Embodiment 
     General Arrangement 
     At first, a first embodiment of this disclosure will be described. A printer  1  which is an image forming apparatus relating to the first embodiment is a laser beam printer of an electrophotographic system. To be noted, the scope of this disclosure is not limited by sizes, materials, shapes, relative arrangements, and the likes of components described in the following embodiments unless otherwise specifically stated. 
     As shown in  FIG.  1   , the printer  1  includes an image forming unit  100  forming an image on a sheet P, a sheet feeding unit  15 , a fixing unit  20 , a sheet discharge roller pair  23 , and an inversion roller pair  25 . The image forming unit  100  includes four process cartridges  90 Y,  90 M,  90 C, and  90 K respectively forming toner images of four colors of yellow (Y), magenta (M), cyan (C), and black (K), and a scanner unit  4 . 
     To be noted, the four process cartridges  90 Y,  90 M,  90 C, and  90 K are the same in configurations except for differences in the colors of formed images. Accordingly, only the configuration and an image forming process of the process cartridge  90 Y will be described, and descriptions of the other process cartridges  90 M,  90 C, and  90 K will be omitted herein. 
     The process cartridge  90 Y includes a photosensitive drum  2 , a charge roller  3 , a developing roller  5 , and a cleaning blade  6 . The photosensitive drum  2  is coated with an organic photo conductive layer around an outer circumferential surface of an aluminum cylinder, and is rotatably driven by a driving motor, not shown. Further, an intermediated transfer belt  8  wound around a driving roller  9  and a tension roller  10  is disposed in the image forming unit  100 , and primary transfer rollers  7 Y,  7 M,  7 C, and  7 K are disposed inside the intermediated transfer belt  8 . Further, a secondary transfer roller  11  is disposed across the intermediated transfer belt  8  opposite the driving roller  9 , and the intermediated transfer belt  8  and the secondary transfer roller  11  form a transfer nip N 1  transferring the image to the sheet P that is conveyed. 
     The sheet feeding unit  15  is disposed in a lower part of the printer  1 , and includes a cassette  16  storing the sheet P, a pickup roller  17 , serving as a sheet feeding unit, supported by the cassette  16  and capable of feeding the sheet P, and a separation roller  14 . The fixing unit  20  includes a fixing roller and a press roller providing the heat and the pressure to the sheet. 
     Next, an image forming operation of the printer  1  which is configured as described above will be described. When an image signal is input to the scanner unit  4  from a personal computer, not shown, and the like, a laser beam corresponding to the image signal is irradiated from the scanner unit  4  onto the photosensitive drum  2  in the process cartridge  90 Y. 
     At this time, a surface of the photosensitive drum  2  has been uniformly charged at a predetermined polarity and electric potential by the charge roller  3  beforehand, and, by irradiated with the laser beam by the scanner unit  4 , an electrostatic latent image is formed on the surface. The electrostatic latent image formed on the photosensitive drum  2  is developed by the developing roller  5 , and the toner image of yellow (Y) is formed on the photosensitive drum  2 . 
     Similarly, the laser beam is irradiated to each of the photosensitive drums  2  in the process cartridges  90 M,  90 C, and  90 K from the scanner unit  4 , and the toner images of magenta (M), cyan (C), and black (K) are formed on the respective photosensitive drums. The toner image of each color formed on each photosensitive drum is transferred to the intermediated transfer belt  8  by the primary transfer rollers  7 Y,  7 M,  7 C, and  7 K, and is conveyed to transfer nip N 1  by the intermediated transfer belt  8  rotatably driven by the driving roller  9 . To be noted, the image forming process of each color is performed in a timing superimposing the toner image on an upstream toner image which has been primarily transferred onto the intermediated transfer belt  8 . To be noted, after the toner image has been transferred by the primary transfer roller  7 Y, the toner remained on the photosensitive drum  2  is collected by the cleaning blade  6 . 
     In parallel with this image forming process, the sheet P stored in the cassette  16  of the sheet feeding unit  15  is sent out by the pickup roller  17 , and is separated into one sheet a time by the separation roller  14 . Then, the skew of the sheet P is corrected by a conveyance roller pair  18  and a registration roller pair  19 , and the sheet P is conveyed by the registration roller pair  19  in a predetermined timing synchronizing with a transfer timing of the image at the transfer nip N 1 . To be noted, the printer  1  includes a manual feed tray  13  on which the sheet P is loaded, and it is also acceptable to feed the sheet P loaded on the manual feeding tray  13  by a manual feeding roller  13   a  and a separation roller  13   b.    
     Then, a full color toner image on the intermediated transfer belt  8  is transferred to the sheet P at the transfer nip N 1  by a secondary transfer bias applied to the secondary transfer roller  11 . The toner remained on the intermediated transfer belt  8  is collected by a cleaning apparatus, not shown. The sheet P on which the toner image has been transferred is provided with the predetermined heat and pressure at the fixing unit  20 , and the toner is melted and bonded (fixed). The sheet P passed through the fixing unit  20  is guided to the sheet discharge roller pair  23  by a guide member  26 , and discharged to a sheet discharge tray  24  by the sheet discharge roller pair  23 . 
     When a duplex printing job to form the image on both surfaces of the sheet P is input, the sheet P on whose surface the image has been formed by the transfer nip N 1  is guided to the inversion roller pair  25  by the guide member  26 . Then, the sheet P is inverted by the inversion roller pair  25 , and conveyed to a duplex conveyance path  27 . The sheet P guided to the duplex conveyance path  27  is again conveyed to the registration roller pair  19 , and, after the image has been formed on a back surface at the transfer nip N 1 , is discharged to the sheet discharge tray  24  by the sheet discharge roller pair  23 . 
     Sheet Storage Apparatus 
     Next, regarding a sheet storage apparatus  60 , the cassette  16  and an internal configuration of the cassette  16  will be described in detail. As shown in  FIGS.  2  to  4   , the sheet storage apparatus  60  includes the cassette  16  which is capable of attaching to and being drawn out from an apparatus body  1 A of the printer  1 . That is, the sheet storage apparatus  60  including the cassette  16  is attached to the apparatus body  1 A in an attaching direction AD. The cassette  16  includes a cassette body  30 , serving as a storage portion storing the sheet P, and a pair of guide rails  35 . The pair of guide rails  35 , serving as guided portions, are disposed at both sides of the cassette body  30 , extend in the attaching direction AD, and, when the sheet storage apparatus  60  is attached to the apparatus body  1 A in the attaching direction AD, slide towards the apparatus body  1 A. 
     Further, the sheet storage apparatus  60  includes a lift plate  34  supported, with respect to the cassette body  30 , pivotably around a pivot shaft  34   a  as center and stacking the sheet P, and a pair of side regulation plates  31  and  131  movably supported in a moving direction MD with respect to the cassette body  30 . Further, the sheet storage apparatus  60  includes a trailing edge regulation plate  65  regulating a position of a trailing edge of the sheet P stacked on the lift plate  34 , and a pinion gear  33 , serving as a gear member, rotatably supported with respect to the cassette body  30 . To be noted, in this embodiment, the moving direction MD is a direction parallel to the attaching direction AD and a drawing out direction of the cassette  16  with respect to the apparatus body  1 A, and is a width direction orthogonal to a sheet feeding direction. Further, the direction parallel to the attaching direction AD includes a direction that is within ten degrees with respect to the attaching direction AD, and it is acceptable if the moving direction MD is within ten degrees with respect to the attaching direction AD. 
     The pair of guide rails  35  slide on apparatus body side rails, not shown, disposed on the apparatus body  1 A, so that the cassette  16  is guided towards the apparatus body  1 A smoothly. When an image forming job is started, the lift plate  34  ascends to a position where an uppermost sheet stacked on the lift plate  34  comes into contact with the pickup roller  17 . 
     As shown in  FIG.  4   , the side regulation plate  31 , serving as a moving unit and a first moving unit, is constructed by a regulation member  31 A, serving as a first regulation member, and a rack member  32 , serving as an extending member and a first extending member. The regulation member  31 A includes a regulation surface  31 B regulating a position, in the moving direction MD, of the sheet stored in the cassette body  30 . The side regulation plate  131 , serving as a second moving unit, is also constructed by a regulation member  131 A, serving as a second regulation member, and a rack member  132 , serving as a second extending member. The regulation member  131 A includes a regulation surface  131 B regulating a position of the sheet stored in the cassette body  30  in the moving direction MD. The cassette body  30  and the regulation members  31 A and  131 A are made from resin material, and the rack members  32  and  132  are made from metal material such as sheet metal. 
     The rack members  32  and  132  respectively include rack portions  42  and  142  capable of engaging with the pinion gear  33 , and these rack portions  42  and  142  are disposed so as to face each other across the pinion gear  33 . Then, when either one of the side regulation plates  31  and  131  is moved by a user in the moving direction MD, the other one of the side regulation plates  31  and  131  is configured to move in the moving direction MD by actions of the rack portions  42  and  142  and the pinion gear  33 . At this time, the side regulation plates  31  and  131  move in directions opposite each other in the moving direction MD. For example, when the side regulation plate  31  moves in a predetermined direction inside the moving direction MD, the side regulation plate  131  moves in an opposite direction of the predetermined direction. 
     Hereinafter, since the side regulation plates  31  and  131  are almost similar in configurations, only the side regulation plate  31  will be described in detail, and descriptions of the side regulation plate  131  will be omitted herein. 
     Detailed Configurations of Bonding Portion of Side Regulation Plate 
     As described later, the regulation member  31 A and the rack member  32  constructing the side regulation plate  31  are bonded to each other by adhesive. At first, using  FIG.  5   , a bonding portion  61  of the regulation member  31 A will be described in detail. As shown in  FIG.  5   , the bonding portion  61  includes a bonding surface  36 , serving as a first bonding surface extending parallel to the moving direction MD, a pair of guide ribs  31 G and  31 G protruding upwards from the bonding surface  36 , and a regulation rib  31 F disposed so as to couple the guide ribs  31 G and  31 G to each other. The bonding surface  36  includes adhesive coating surfaces  36 A and  36 B on which the adhesive  40  is coated by an adhesive coater  41 . 
     The pair of guide ribs  31 G and  31 G, serving as a wall portion, are disposed so as to face each other across the adhesive coating surfaces  36 A and  36 B in an orthogonal direction OD orthogonal to the moving direction MD, and extend along the moving direction MD. The regulation rib  31 F extends in the orthogonal direction OD so as to couple the pair of guide ribs  31 G and  31 G to each other. Therefore, these guide ribs  31 G,  31 G, and regulation rib  31 F are formed approximately in a rectangular with one side open shape so that it is possible to easily position the rack member  32 . 
     A hole portion  31 C capable of accommodating insertion of a tip portion  32 C (refer to  FIG.  6   ) of the rack member  32  is formed below the regulation rib  31 F. Further, a hook portion  31 D, having an L-shaped cross section while protruding upwards from the bonding surface  36 , and a snap fit  31 E protruding upwards from the bonding surface  36  are formed on the bonding surface  36 . Since a groove  31 H is formed in a rectangular with one side open shape around the snap fit  31 E, the snap fit  31 E is easily deformed elastically in a height direction. 
     Detailed Configurations of Bonding Portion of Rack Member 
     Next, using  FIG.  6   , a bonding portion  62  of the rack member  32  will be described in detail. As shown in  FIG.  6   , the bonding portion  62  includes a first portion  43  including the tip portion  32 C, a second portion  44  including a rack portion  42 , and a step portion  45  connecting the first portion  43  and the second portion  44 . The step portion  45  couples one end of the first portion  43  to one end of the second portion  44  in the height direction. 
     A convex portion  44   a  protruding upwards is formed on the second portion  44  by a press working and the like, and formed lengthily approximately over a whole length of the second portion  44  in the moving direction MD. The intensity of the rack member  32  is improved by these step portion  45  and convex portion  44   a.    
     The rack member  32  includes a bonding surface  37 , serving as a second bonding surface, bonded to the bonding surface  36  of the regulation member  31 A by the adhesive  40  and extending parallel to the first bonding surface  36 . The bonding surface  37  includes a first adhered surface  37 A formed on the second portion  44  and capable of being adhered to the adhesive coating surface  36 A of the regulation member  31 A, and a second adhered surface  37 B formed on the first portion  43  and capable of being adhered to the adhesive coating surface  36 B of the regulation member  31 A. A rectangular hole  32 D is formed in the convex portion  44   a  of the second portion  44 , and a snap fit hole  32 E is formed in the first portion  43 . 
     Bonding Method to Bond Regulation Member and Rack Member 
     Next, using  FIGS.  7 A to  8 B , a bonding method to bond the regulation member  31 A and the rack member  32  will be described. At first, as shown in  FIG.  7 A , an assembly worker (hereinafter simply referred to as a worker) coats the adhesive  40  on the adhesive coating surfaces  36 A and  36 B of the regulation member  31 A with the adhesive coater  41 . To be noted, an assembly process of this embodiment is not limited to the manual work by personnel, and it is acceptable to perform the process by a mechanical means. 
     Then, as shown in  FIG.  7 B , the worker inserts the tip portion  32 C into the hole portion  31 C while tilting a posture of the rack member  32  with respect to the rack member  32  so that the rack member  32  does not come into contact with the adhesive coating surfaces  36 A and  36 B. Next, as shown in  FIG.  8 A , the worker rotates the rack member  32 , and fits the bonding surface  37  of the rack member  32  on the bonding surface  36  of the regulation member  31 A. To be noted, at this time, the snap fit  31 E of the regulation member  31 A is elastically deformed downwards by being pressed with the rack member  32 . 
     Since the pair of guide ribs  31 G and  31 G are formed on the regulation member  31 A, by rotating the rack member  32  between the guide ribs  31 G and  31 G, it is possible to easily position the rack member  32  correctly. Further, since the guide ribs  31 G and  31 G are disposed so as to enclose the adhesive coating surfaces  36 A and  36 B, even if the adhesive  40  of a low viscosity is coated on the adhesive coating surfaces  36 A and  36 B, it is possible to reduce an effluence of the adhesive  40  from the bonding surface  36  to other areas. Further, since the bonding surface  36  is divided from the other areas by the guide ribs  31 G and  31 G, it is possible to define a coating position of the adhesive  40 . Therefore, it is possible to improve assemblability. 
     Then, when the bonding surfaces  36  and  37  are fitted on each other, the hook portion  31 D of the regulation member  31 A is inserted into the rectangular hole  32 D of the rack member  32 . Next, the worker positions the snap fit  31 E and the snap fit hole  32 E at a correct position by slidingly moving the rack member  32  to a side of the tip portion  32 C. Herewith, the snap fit  31 E swings upwards, and engages with the snap fit hole  32 E. To be noted, similar assembling and positioning methods as described above are also applied to the side regulation plate  131 . 
     In a state where the rack member  32  is assembled to the regulation member  31 A, relative movements of the regulation member  31 A and the rack member  32  in a debonding direction of the bonding surfaces  36  and  37 , namely, in a normal line direction ND of the bonding surfaces  36  and  37  are regulated by the hook portion  31 D and the regulation rib  31 F. In more particular, the hook portion  31 D of the regulation member  31 A and the regulation rib  31 F respectively engage with an edge portion  32 Da of the rectangular hole  32 D formed in the rack member  32  and the tip portion  32 C. In other words, when viewed in the normal line direction ND, the hook portion  31 D and the regulation rib  31 F are positioned at positions which respectively overlap the edge portion  32 Da and the tip portion  32 C. To be noted, the hook portion  31 D and the regulation rib  31 F constitute a first engagement portion, and the edge portion  32 Da and the tip portion  32 C constitute a second engagement portion. 
     Therefore, it is possible to supplement the intensity of the adhesive  40  in the debonding direction (in the normal line direction ND), and possible to improve the accuracy of relative positions of the regulation member  31 A and the rack member  32  in the normal line direction ND. 
     Further, by engagement of the snap fit  31 E and the snap fit hole  32 E, the relative movements of the regulation member  31 A and the rack member  32  in a shearing direction of the bonding surfaces  36  and  37 , namely, in a direction parallel to the bonding surfaces  36  and  37  are regulated. Therefore, after the bonding surfaces  36  and  37  were bonded by the adhesive  40 , it is not necessary to lock the regulation member  31 A and the rack member  32  by a clamping tool and the like during a time until the adhesive  40  has stiffened to a practical shear strength. For example, in a case where the practical shear strength of the adhesive  40  is equal to or more than 23 kgf (kilogram force), it takes about 8 minutes for the adhesive  40  to stiffen. To be noted, the snap fit  31 E constitutes a third engagement portion, and the snap fit hole  32 E constitutes a fourth engagement portion engaging with the third engagement portion. 
     As described above, by temporarily fixing the regulation member  31 A and the rack member  32  by engaging the snap fit  31 E with the snap fit hole  32 E, without needing a special tool, it is possible to assemble the regulation member  31 A and the rack member  32  at low cost and easily. Further, if external force is not exerted to the regulation member  31 A and the rack member  32  in the temporarily fixed state, it is possible to move to a next assembly process and also proceed to assemble to the cassette  16 . 
     Replenishment of Sheet to Cassette 
     Next, a sheet replenishing operation to the cassette  16  will be described. As shown in  FIG.  9 A , at a time of replenishing the sheet P to the cassette  16 , at first, a user draws out the cassette  16  from the apparatus body  1 A. Then, the user sets the sheet P in the cassette  16 , and aligns the side regulation plates  31  and  131  with side edges of the sheet P. 
     Thereafter, as shown in  FIG.  9 B , the user attaches the cassette  16  to the apparatus body  1 A in the attaching direction AD. At this time, the cassette  16  is attached to the apparatus body  1 A smoothly by the guide rail  35  disposed on the cassette  16 . Then, the cassette  16  is positioned at an attached position by abutting a positioning portion disposed on the cassette  16  or the guide rail  35  onto an abutment portion disposed on the apparatus body  1 A. 
     At this time, a case where the cassette  16  is thrusted into the apparatus body  1 A is considered. When the cassette  16  abuts on the apparatus body  1 A at the attached position, the sheet P presses the side regulation plate  31  in the moving direction MD (in the attaching direction AD) by the law of inertia. 
     At this point, in this embodiment, the regulation member  31 A and the rack member  32  are bonded by adhering the bonding surfaces  36  and  37  extending parallel to the moving direction MD with the adhesive  40 . Therefore, a load exerted to the regulation member  31 A of the side regulation plate  31  from the sheet P acts as the shearing force on the bonding surfaces  36  and  37  between the regulation member  31 A and the rack member  32 . 
     However, since the adhesive  40  is strong in the shear strength, when the above load is exerted, the bonding of the bonding surfaces  36  and  37  is maintained, and it is possible to reduce the breakage of the regulation member  31 A and the rack member  32 . Further, since the bonding of the bonding surfaces  36  and  37  with the adhesive  40  is performed without fastening by a fastening member such as a screw and achieved at low cost, it is possible to construct the side regulation plate  31  at low cost and high intensity. Therefore, it is possible to suppress a wobble between the regulation member  31 A and the rack member  32 , and reduce the dispersion of printing precision. Further, since it is not necessary to dispose a damping member such as a damper between the cassette  16  and the apparatus body  1 A, the cost reduction in and the miniaturization of the apparatus are enabled. 
     Further, in the case where the cassette  16  is thrusted into the apparatus body  1 A, as shown in  FIG.  9 C , in some cases, by being pushed by the sheet P, the regulation member  31 A of the side regulation plate  31  comes into contact with the cassette body  30 . At this time, the side regulation plate  131  synchronizing with the side regulation plate  31  moves in a direction away from the sheet P. The regulation member  31 A of the side regulation plate  31  comes into contact with the cassette body  30  while some brakes are being applied by the engagement resistance between the rack members  32  and  132  of the side regulation plates  31  and  131  and the pinion gear  33 , and the sliding resistance at a time of the movements of the side regulation plates  31  and  131 . 
     Further, since the sheet P stored in the cassette  16  is also not a rigid body, the sheet P adsorbs an impact at a time when the regulation member  31 A comes into contact with the cassette body  30 . Further, since the regulation member  31 A and the cassette body  30  are formed from resin material, the regulation member  31 A and the cassette body  30  each deform elastically so that the impact is absorbed. Further, since the regulation member  31 A is formed from resin material, at a time of colliding with the cassette body  30 , the regulation member  31 A is not plastically deformed to bend as sheet metal so that it is possible to regulate the position of the sheet precisely. 
     As described above, since the load exerted to the regulation member  31 A from the sheet P is alleviated to some extent, combined with the high intensity of the shear strength of the adhesive  40  mentioned above, it is possible to reduce the deformation and the positional displacement of the regulation member  31 A and the rack member  32 . Further, since the rack member  32  is formed from metal material, it is possible to suppress a bend so as to reduce a tooth jump with respect to the pinion gear  33 . 
     Shear Strength 
     Next, the shear strength of the adhesive  40  coated on the bonding surfaces  36  and  37  in this embodiment will be described. For example, in a case where 500 sheets of the sheet of an A4 size having a grammage of 80 g/m 2  are stacked inside the cassette  16 , the weight of these sheets becomes about 2.5 kg. Hereinafter, it is assumed that, in the case where the cassette  16  is thrusted into the apparatus body  1 A, the cassette  16  is attached at a cassette attaching speed of 2.2 m/sec which is about 1.5 times faster than a normal cassette attaching speed of about 1.5 m/sec. 
     When the cassette  16  abuts on the abutment portion of the apparatus body  1 A at this speed, in accordance with an equation (1) relating to kinetic energy, the impact (load) W exerted by the sheet P stored in the cassette  16  on the regulation member  31 A becomes as follows: 
     
       
         
           
             
               
                 
                   
                     
                       
                         W 
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                           1 
                           ⁢ 
                           
                             / 
                           
                           ⁢ 
                           2 
                           ⁢ 
                           
                             
                               mv 
                               2 
                             
                             ⁡ 
                             
                               ( 
                               
                                 
                                   W 
                                   ⁢ 
                                   
                                     : 
                                   
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     work 
                                     ⁡ 
                                     
                                       ( 
                                       
                                         joule 
                                         ⁡ 
                                         
                                           ( 
                                           J 
                                           ) 
                                         
                                       
                                       ) 
                                     
                                   
                                 
                                 , 
                                 
                                   m 
                                   ⁢ 
                                   
                                     : 
                                   
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     mass 
                                     ⁡ 
                                     
                                       ( 
                                       kg 
                                       ) 
                                     
                                   
                                 
                                 , 
                                 
                                   v 
                                   ⁢ 
                                   
                                     : 
                                   
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     velocity 
                                     ⁡ 
                                     
                                       ( 
                                       
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                                         ⁢ 
                                         
                                           / 
                                         
                                         ⁢ 
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                                       ) 
                                     
                                   
                                 
                               
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                         = 
                         6.05 
                       
                     
                   
                 
               
               
                 
                   ( 
                   1 
                   ) 
                 
               
             
           
         
       
     
     The regulation member  31 A slides by a few millimeters from a position corresponding to the A4 size sheet, and collides with the cassette body  30 . At this time, impact force F is determined by an equation of motion (2), an equation of speed/linear motion (3), and an equation about work (4),
 
 F=ma   (2)
         (F: force (newton (N), m: mass (kg), a: acceleration (m/sec 2 ))
 
 as = ½ v   2   (3)
   (a: acceleration (m/sec 2 ), s: braking distance (m), v: velocity (m/sec))
 
 W=Fs   (4)
   (W: work (J), F: force (N), s: braking distance (m))
 
Therefore,
       

     
       
         
           
             W 
             = 
             
               
                 
                   ( 
                   ma 
                   ) 
                 
                 ⁢ 
                 s 
               
               = 
               
                 
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     Since, in comparison with the calculation formula, actually, the impact is absorbed by the impact absorption due to the elasticity of the sheet P, the sliding resistance between the rack member  32  and the pinion gear  33 , the bend and the deformation of the regulation member  31 A, the bend and the deformation of the cassette body  30 , and the like, it is assumed that the braking distance is about 10 millimeters. 
     If s equals 0.01 meter, then F becomes:
 
 F =6.05/0.01=605 (N)=62 (kgf)
 
Therefore, it is assumed that the impact force (shear strength) exerted on the bonding surfaces  36  and  37  of the regulation member  31 A and the rack member  32  is 62 kgf.
 
     To be noted, the adhesive  40  used in this embodiment is an acrylic two component structural adhesive (for example, 3921/3926 (trade name) manufactured by ThreeBond Holdigs Co., Ltd., Y611KuroS, Y612BLACK (trade name) manufactured by CEMEDINE Co., Ltd., and the like). The intensity per unit area is 0.38 kgf/mm 2 . 
     Since the total area of the adhesive coating surfaces  36 A and  36 B of the regulation member  31 A is 327 mm 2 , the shear strength becomes 125 kgf. Therefore, there is an intensity margin of twice as large as the calculated impact force of 62 kgf. Incidentally, in a case where the regulation member  31 A and the rack member  32  are fastened with an m3 screw (screw of 3 millimeters in nominal diameter), since a piece of the m3 screw is displaced with the shear strength of about 16 kgf, it is not possible to withstand the calculated impact force of 62 kgf by the single screw so that fastening with a plurality of screws is necessary. 
     At the normal cassette attaching speed of 1.5 m/sec, the impact force is about 25 kgf, and this is about 20% of the shear strength of the adhesive of 125 kgf. Therefore, since it is possible to withstand the impact for about 100,000 times according to an estimation of the repeated breaking strength of the adhesive, there are adequate margins to withstand the impact even after taking into consideration a product life. 
     As described above, it is possible to bond the bonding surfaces  36  and  37  by the adhesive  40  at low cost, and construct the side regulation plate  31  at low cost and high intensity. 
     Second Embodiment 
     Next, while a second embodiment of this disclosure will be described, the second embodiment is constituted by using a double-sided tape  50  instead of the adhesive  40  of the first embodiment. Therefore, configurations similar to the first embodiment will be described by omitting illustrations or by putting the same reference characters on drawings. 
     Detailed Configurations of Bonding Portion of Side Regulation Plate 
     As described later, a regulation plate  231 A, serving as the first regulation member relating to this embodiment, and a rack member  232 , serving as the extending member and the first extending member, are bonded to each other by the double-sided tape  50 . At first, using  FIG.  10   , a bonding portion  261  of the regulation plate  231 A will be described in detail. As shown in  FIG.  10   , the bonding portion  261  includes the bonding surface  36  extending in parallel to the moving direction MD, the pair of guide ribs  31 G and  31 G protruding upwards from the bonding surface  36 , and the regulation rib  31 F disposed so as to couple the guide ribs  31 G and  31 G to each other. 
     The hole portion  31 C capable of accommodating the insertion of the tip portion  32 C (refer to  FIG.  11   ) of the rack member  232  is formed below the regulation rib  31 F. Further, a boss portion  51  protruding upwards from the bonding surface  36  and having a cylindrically shaped cross section is formed on the bonding surface  36 . 
     Detailed Configurations of Bonding Portion of Rack Member 
     Next, using  FIG.  11   , a bonding portion  262  of the rack member  232  will be described in detail. As shown in  FIG.  11   , the bonding portion  262  includes a first portion  243  including the tip portion  32 C, a second portion  244  including the rack portion  42 , and a step portion  245  coupling the first portion  243  and the second portion  244 . The step portion  245  couples one end of the first portion  243  to one end of the second portion  244  in a height direction. 
     The convex portion  44   a  protruding upwards is formed on the second portion  244  by the press working and the like, and formed lengthily approximately over a whole length of the second portion  244  in the moving direction MD. The intensity of the rack member  232  is improved by these step portion  245  and convex portion  44   a.    
     The rack member  232  includes the bonding surface  37  bonded to the bonding surface  36  of the regulation member  231 A by the double-sided tape  50  and extending parallel to the first bonding surface  36 . A positioning hole  52  is formed in the convex portion  44   a  of the second portion  244 . 
     Bonding Method to Bond Regulation Member and Rack Member 
     Next, using  FIGS.  12 A to  12 C , a bonding method to bond the regulation member  231 A and the rack member  232  will be described. At first, as shown in  FIG.  12 A , the worker sticks the double-sided tape  50  on the bonding surface  36  of the regulation member  231 A, and removes a release paper. To be noted, an assembly process of this embodiment is not limited to the manual work by personnel, and it is acceptable to perform the process by a mechanical means. 
     Then, as shown in  FIG.  12 B , the worker inserts the tip portion  32 C into the hole portion  31 C while tilting a posture of the rack member  32  with respect to the regulation plate  231 A so that the rack member  232  does not come into contact with the double-sided tape  50 . Next, as shown in  FIG.  12 C , the worker rotates the rack member  232 , and fits the bonding surface  37  of the rack member  232  on the bonding surface  36  of the regulation member  231 A. 
     Since the pair of guide ribs  31 G and  31 G are formed on the regulation member  231 A, by rotating the rack member  232  between the guide ribs  31 G and  31 G, it is possible to easily position the rack member  232 . Further, since the guide ribs  31 G and  31 G divide the bonding surface  36  from other areas, it is possible to define a sticking position of the double-sided tape  50 . Therefore, it is possible to improve assemblability. 
     Then, when the bonding surfaces  36  and  37  are fitted on each other, the boss portion  51  of the regulation member  231 A is inserted into the positioning hole  52  of the rack member  232 . Herewith, relative movements of the regulation member  231 A and the rack member  232  in a shearing direction of the bonding surfaces  36  and  37 , namely, in a direction parallel to the bonding surfaces  36  and  37  are regulated, and the regulation member  231 A and the rack member  232  are positioned by each other. To be noted, the boss portion  51  constitutes the third engagement portion, and the positioning hole  52  constitutes the fourth engagement portion engaging with the third engagement portion. Further, similar assembling and positioning methods as described above are also applied to the side regulation plate  131 . 
     Since the shear strength of the double-sided tape  50  is strong, as described in the first embodiment, even if a load is exerted on the regulation member  231 A from the sheet P, the bonding of the bonding surfaces  36  and  37  is maintained, and it is possible to reduce a breakage of the regulation member  231 A and the rack member  232 . Further, since the bonding of the bonding surfaces  36  and  37  with the double-sided tape  50  is performed without fastening by a fastening member such as a screw and the like, and achieved at low cost without needing any special tools, it is possible to construct the side regulation plate  31  at low cost and high intensity. 
     In a state where the rack member  232  is fitted on the regulation member  231 A, the relative movements of the regulation member  231 A and the rack member  232  in the debonding direction of the bonding surfaces  36  and  37 , namely, in the normal line direction ND of the bonding surfaces  36  and  37  are regulated by the regulation rib  31 F. Therefore, it is possible to supplement the intensity of the double-sided tape  50  in the debonding direction (in the normal line direction ND), and possible to improve the accuracy of relative positions of the regulation member  231 A and the rack member  232  in the normal line direction ND. 
     Further, since the double-sided tape  50  does not need such a hardening time that is needed for the adhesive  40  of the first embodiment, a curing time is not necessary. Further, since, in a case of faulty sticking, it is possible to peel off and stick again the double-sided tape  50 , it is possible to improve the assemblability. Therefore, it is possible to assemble the regulation member  231 A and the rack member  232  more easily, and possible to improve the assemblability along with reducing cost. 
     Shear Strength 
     Next, the shear strength of the double-sided tape  50  sticked on the bonding surfaces  36  and  37  in this embodiment will be described. The double-sided tape  50  used in this embodiment is, for example, #8616CH (trade name) manufactured by DIC Corporation, and the shear strength of the double-sided tape  50  is 0.09 kgf/mm 2 . Therefore, so as to obtain the shear strength of 62 kgf calculated in the first embodiment, a bonding area of 689 mm 2  is required. Therefore, by enlarging the bonding area of the double-sided tape  50  as much as possible, it is possible to secure the margin for the shear strength. 
     Other Embodiments 
     While, in any of the embodiments described above, the sheet storage apparatus  60  includes the pair of side regulation plates movable in a direction approaching to or separating from each other, it is not limited to this. For example, it is acceptable to configure the sheet storage apparatus  60  in such a manner that one side of the side regulation plates is disposed non-movably and only the other side is disposed movably. 
     Further, while, in any of the embodiments described above, the side regulation plate is constructed by the regulation member regulating the position of the sheet in the moving direction MD and the rack member engaging with the pinion gear, it is not limited to this. For example, it is acceptable to apply a guide member, instead of the rack member, guiding the side regulation plate in the moving direction MD with respect to the cassette body  30 . Regarding the guide member, it is not necessary to dispose a rack portion. 
     Further, while, in any of the embodiments described above, the bonding surfaces  36  and  37  are disposed parallel to the moving direction MD, it is not limited to this. For example, it is acceptable if the bonding surfaces  36  and  37  extend in a direction along the moving direction MD. In other words, it is acceptable if the bonding surfaces  36  and  37  extend in a direction having a component of the moving direction MD. Further, while the moving direction MD is a direction parallel to the attaching and detaching directions of the cassette  16 , it is not limited to this. 
     Further, while, in any of the embodiments described above, the regulation members  31 A and  231 A are formed from resin material and the rack members  32  and  232  are formed from metal material, it is not limited to this. For example, it is acceptable that both of the regulation member and the rack member are formed from resin material, and that both of the regulation member and the rack member are formed from metal material. 
     Further, while, in the embodiments described above, the bonding surfaces  36  and  37  are bonded by the adhesive  40  or the double-sided tape  50 , it is not limited to this. For example, it is acceptable to bond the bonding surfaces  36  and  37  by using both of the adhesive  40  and the double-sided tape  50 . Further, it is acceptable to bond the bonding surfaces  36  and  37  by a method different from the adhesive  40  and the double-sided tape  50 . For example, it is acceptable to bond the bonding surfaces  36  and  37  by welding and insert molding, and is acceptable if surfaces extending along the moving direction MD are bonded to each other by a method other than the fastening member such as the screw. 
     Further, while in the first embodiment, the relative movements of the regulation member  31 A and the rack member  32  in the normal line direction ND are regulated by respectively engaging the hook portion  31 D and the regulation rib  31 F with the edge portion  32 Da and the tip portion  32 C, it is not limited to this. For example, it is acceptable that only either one of the engagements, namely, the engagement of the hook portion  31 D and the edge portion  32 Da and the engagement of the regulation rib  31 F and the tip portion  32 C is disposed, and acceptable that none of these two engagements is disposed. Further, shapes of these hook portion  31 D, edge portion  32 Da, and tip portion  32 C are not limited. 
     Further, while in the first embodiment, the hook portion  31 D and the regulation rib  31 F are disposed in the regulation member  31 A and the edge portion  32 Da and the tip portion  32 C are disposed in the rack member  32 , it is not limited to this. For example, it is acceptable that the edge portion  32 Da and the tip portion  32 C are disposed in the regulation member  31 A and the hook portion  31 D and the regulation rib  31 F are disposed in the rack member  32 . That is, it is acceptable that the hook portion  31 D and the regulation rib  31 F are disposed in either one of the regulation member  31 A and rack member  32 , and the edge portion  32 Da and the tip portion  32 C are disposed in the other one of the regulation member  31 A and the rack member  32 . 
     Further, while in the first embodiment, the snap fit  31 E is disposed in the regulation member  31 A and the snap fit hole  32 E is disposed in the rack member  32 , it is not limited to this. For example, it is acceptable that the snap fit hole  32 E is disposed in the regulation member  31 A and the snap fit  31 E is disposed in the rack member  32 . That is, it is acceptable that the snap fit  31 E is disposed in either one of the regulation member  31 A and the rack member  32 , and the snap fit hole  32 E is disposed in the other one of the regulation member  31 A and the rack member  32 . Further, shapes of the snap fit  31 E and the snap fit hole  32 E are not limited. 
     Further, while in the second embodiment, the boss portion  51  is disposed in the regulation member  231 A and the positioning hole  52  is disposed in the rack member  232 , it is not limited to this. For example, it is acceptable that the positioning hole  52  is disposed in the regulation member  231 A and the boss portion  51  is disposed in the rack member  232 . That is, it is acceptable that the boss portion  51  is disposed in either one of the regulation member  231 A and the rack member  232 , and the positioning hole  52  is disposed in the other one of the regulation member  231 A and the rack member  232 . Further, shapes of the boss portion  51  and the positioning hole  52  are not limited. Further, it is acceptable to eliminate the boss portion  51  and the positioning hole  52 . 
     Further, while, in any of the embodiments described above, the descriptions are provided using the printer  1  of the electrophotographic system, the present disclosure is not limited to this. For example, it is possible to apply the present disclosure to an image forming apparatus of an ink jet system which forms the image on the sheet by ejecting a liquid ink through a nozzle. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
     This application claims the benefit of Japanese Patent Application No. 2020-157201, filed Sep. 18, 2020 which is hereby incorporated by reference herein in its entirety.