JP2011128553A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus enabling easy removal of a sheet even if a layout where a plurality of conveyance passages join one another is employed. <P>SOLUTION: This image forming apparatus includes an image forming section for forming an image in a sheet, a drawing unit having a first conveyance wall, a second conveyance wall for defining the conveying direction together with the first conveyance wall, and a first conveyance roller, and a conveyance unit having a second conveyance roller. The first conveyance wall and the second conveyance wall form the first conveyance passage, and the first conveyance roller and the second conveyance roller form the second conveyance passage joining the first conveyance passage. The conveyance unit can move between a first position at which the second conveyance roller and first conveyance roller form the second conveyance passage and a second position at which the second conveyance roller separates from the first conveyance roller. When the conveyance unit is at the second position, the drawing unit can be drawn so that the second conveyance wall separates from the first conveyance wall. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus that forms an image on a sheet.

  Image forming apparatuses such as copying machines, printers, and facsimile machines are widely used. Such clogging of sheets in the image forming apparatus significantly reduces the efficiency of image forming processing such as printing and copying.

  In an image forming apparatus that forms an image on a sheet while conveying a sheet having relatively low rigidity, clogging of the sheet in the sheet supply port or the sheet conveyance path is unavoidable. For this reason, various proposals have been made that make it possible to quickly solve sheet jamming.

  Japanese Patent Application Laid-Open No. 2004-228561 forms a conveyance path in an image forming apparatus using a plurality of rotating members rotatably attached to a housing of the image forming apparatus. By opening the rotating member, the sheet jammed in the middle of the conveyance path is efficiently removed.

JP 2005-82307 A

  The layout of the conveyance path for guiding the conveyance of the sheet is determined according to the performance and function required for the image forming apparatus. In particular, when the layout of the conveyance path is determined so that a plurality of conveyance paths are merged, for example, even if a technique disclosed in Patent Document 1 is used, the image forming apparatus is arranged upstream of the merge section. Sheet clogging that occurs in the conveyance path extending inward of the housing cannot be easily resolved.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an image forming apparatus capable of easily removing a sheet even in a layout in which a plurality of conveyance paths merge. To do.

  An image forming apparatus according to an embodiment of the present disclosure is provided with an image forming unit that forms an image on a sheet, a first transport wall that defines a transport direction of the sheet, and the first transport wall. The first transport roller disposed adjacent to the second transport wall that defines the transport direction together with the first transport wall, and a surface opposite to the surface of the second transport wall that faces the first transport wall. A drawer unit including: a first conveyance wall; and a conveyance unit that includes a second conveyance roller that contacts the first conveyance roller and rotates together with the first conveyance roller, wherein the first conveyance wall and the second conveyance wall are: Forming a first conveyance path formed so that the sheet can be guided, wherein the first conveyance roller and the second conveyance roller are disposed in a second conveyance path that merges with the first conveyance path; , At least one of the first transport path and the second transport path And is conveyed to the image forming unit. The conveyance unit includes a first position where the second conveyance roller forms the second conveyance path together with the first conveyance roller, and the second conveyance roller is the first conveyance. The drawer unit is movable between a second position spaced apart from the rollers, and when the transport unit is in the second position, the drawer unit can be pulled out so that the second transport wall is separated from the first transport wall. (Claim 1).

  According to the above configuration, the first transport path is formed by the first transport wall and the second transport wall disposed to face the first transport wall. The first conveyance wall and the second conveyance wall form a first conveyance path formed so as to be capable of guiding the sheet from the first direction. The drawer unit includes a second transport wall and a first transport roller disposed adjacent to a surface opposite to the surface of the second transport wall facing the first transport wall. The transport unit includes a second transport roller that contacts the first transport roller and rotates together with the first transport roller. The first transport roller and the second transport roller are disposed in a second transport path that joins the first transport path. The sheet is conveyed to the image forming unit through at least one of the first conveyance path and the second conveyance path. The image forming unit forms an image on the sheet. The transport unit is movable between a first position where the second transport roller contacts the first transport roller and a second position where the second transport roller is separated from the first transport roller. Therefore, when the transport unit is in the second position, the second transport roller is separated from the first transport roller, so that the user can easily remove the sheet from the second transport path. When the transport unit is in the second position, the drawer unit can be pulled out such that the second transport wall is separated from the first transport wall. Therefore, when the user pulls out the drawer unit, the second transport wall is separated from the first transport wall, so that the user can easily remove the sheet from the first transport path. Thus, even if the layout is such that a plurality of conveying paths merge, the user can easily remove the sheet.

  In the above configuration, the apparatus further includes a housing including a support wall that supports the drawer unit, and the support wall includes a rail portion that defines a pull-out direction of the drawer unit, and the drawer unit is connected to the rail portion. And a connecting piece that moves along the rail portion, and the rail portion extends between a first end and a second end located above the first end and outside the housing. Preferably, it includes a first section, a second section extending between the second end and a third end located below the second end (Claim 2).

  According to the above configuration, the casing includes the support wall that supports the drawer unit. The support wall includes a rail portion that defines a drawing direction of the drawing unit. The drawer unit further includes a connection piece that is connected to the rail portion and moves along the rail portion. The rail portion includes a first section extending between the first end and a second end located above the first end and outside the housing, and a second section located below the second end and the second end. A second section extending between the three ends. Therefore, the drawer unit is guided by the rail portion, moved obliquely upward, and then pulled out so as to move downward. Since the second section is defined by the second end and the third end and extends downward, the connecting piece that has moved to the second section does not return to the first section and is pulled out against the user's intention. The unit will be fixed in the pulled out position. Thus, the user can easily take out the sheet existing in the first conveyance path.

  In the above configuration, the support wall supports the transport unit so as to be rotatable up and down between the first position and the second position, and the transport unit moves from the second position to the first position. Preferably, the drawer unit is pushed up and the connecting piece moves from the second section to the first section (Claim 3).

  According to the above configuration, the support wall supports the transport unit so as to be rotatable up and down between the first position and the second position. When the transport unit is rotated upward from the second position toward the first position, the drawer unit is pushed up, and the connection piece moves from the second section to the first section. Thus, even if the user pulls out the drawer unit and rotates the transport unit toward the first position, the drawer unit moves toward the first end of the first section, and the second transport wall is the second transport wall. The first conveying path can be reformed by approaching one conveying wall.

  In the above configuration, the drawer unit further includes a projecting piece projecting toward the transport unit, and the projecting piece separates the first transport roller from the transport unit when the drawer unit is pulled out. Preferred (claim 4).

  According to the above configuration, the drawer unit further includes a protruding piece that protrudes toward the transport unit. The protruding piece separates the first transport roller from the transport unit when the drawer unit is pulled out. Therefore, it is possible to avoid the first transport roller from directly colliding with the transport unit, and it is possible to prevent the first transport roller from being damaged.

  The said structure WHEREIN: It is preferable that the said 1st end and the said 3rd end are formed so that the movement of the said connection piece may be stopped (Claim 5).

  According to the above configuration, since the first end and the third end are formed so as to stop the movement of the connecting piece, it is possible to stably determine the movable range of the drawer unit.

  As described above, the present invention makes it possible to easily remove a sheet even in a layout where a plurality of conveyance paths merge.

1 is a diagram schematically showing an internal structure of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view of a drawer unit of the image forming apparatus shown in FIG. 1. It is a perspective view which shows the drawer unit and conveyance unit which exist in a 2nd position. It is a figure which shows schematically the rail part which supports a drawer unit. It is a perspective view which shows the drawer unit which exists in a 1st position. It is a perspective view which shows the drawer unit which moves between a 1st position and a 2nd position. It is a perspective view which shows the drawer unit which exists in a 2nd position.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that terms used in the following description, such as “up”, “down”, “left”, “right” and the like, are merely for the purpose of clarifying the explanation and do not limit the present invention. Not what you want. Further, the term “sheet” used in the following description means copy paper, tracing paper, cardboard, OHP sheet, and other sheets capable of forming an image.

  FIG. 1 schematically shows the internal structure of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus shown in FIG. 1 is a color printer, but may be a monochrome printer, a copying machine, a facsimile apparatus, or other apparatus capable of forming an image on a sheet.

  For example, the image forming apparatus 1 receives a signal including information about an image from the outside, and forms an image based on the signal. The image forming apparatus 1 includes a housing 2 having a substantially rectangular parallelepiped shape. Various apparatuses for forming an image on the sheet S are accommodated in the housing 2 based on signals from the outside.

  The image forming apparatus 1 includes a storage unit 3 for storing the sheet S. The storage unit 3 includes a cassette 31 disposed in the housing 2 and a manual feed tray 32 that protrudes from the left surface of the housing 2. The manual feed tray 32 is formed to be able to support the sheet S. At the base end portion of the manual feed tray 32, a paper feed roller 41 and a separating pad 42 are disposed. The manual feed tray 32 is inclined downward toward the base end portion of the manual feed tray 32, and the sheet S disposed on the manual feed tray 32 contacts the paper feed roller 41 and / or the separation pad 42. When the paper feed roller 41 rotates, the sheet S is fed from the manual feed tray 42 into the housing 2. When a plurality of sheets S are fed into the housing 2 by the paper feed roller 41, the separating pad 42 has a frictional force that prevents the sheet S except the uppermost sheet S from being fed into the housing 2. Cause it to occur. As a result, the sheets S are sent one by one from the manual feed tray 32 into the housing 2.

  The first transport path 43 extends rightward with the paper feed roller 41 and / or the separation pad 42 as a base end. The first transport path 43 is between the upper wall 431 disposed in the housing 2 and the lower wall 432 disposed below the upper wall 431 and opposed to the upper wall 431. It is formed. In the middle of the first conveyance path 43, a plurality of conveyance roller pairs 433 for conveying the sheet S are disposed at appropriate positions.

  The first conveyance path 43 is opposed to the first conveyance wall 434 that defines the sheet conveyance direction from the first direction from left to right to the second direction from bottom to top, and the first conveyance wall 434. And a second conveyance wall 435 that defines the sheet conveyance direction from the first direction to the second direction together with the first conveyance wall. The 2nd conveyance wall 435 is an element contained in the drawer unit 10 mentioned later. The first transfer wall 434 and the second transfer wall 435 form a first transfer path 43 that is curved upward toward the right. In the present embodiment, the first direction is described as a direction from left to right, and the second direction is described as a direction from bottom to top. However, the present invention is not limited to this. . The first direction may be an arbitrary direction in the housing 2, and the second direction may be an arbitrary direction different from the first direction.

  The cassette 31 is disposed below the first conveyance path 43 extending in the first direction. The cassette 31 is detachably attached to the housing 2. The cassette 31 has a substantially box shape opened upward, and is formed so as to accommodate the sheet S. A lift plate 311 formed so as to support the sheet S is disposed in the cassette 31. The lift plate 311 is inclined upward toward the right.

  A pickup roller 44 is disposed on the right end portion of the lift plate 311. The sheet S is sandwiched between the right end portion of the lift plate 311 and the pickup roller 44. When the pickup roller 44 rotates, the sheet S is sent out of the cassette 31. A paper feed roller 45 and a separating roller 46 are disposed downstream of the pickup roller 44. The paper feed roller 45 rotates in the same direction as the pickup roller 44 and sends the sheet S downstream. A separating roller 46 disposed below the sheet feeding roller 45 rotates so as to feed the sheet S fed from the pickup roller 44 toward the cassette 31. Therefore, when the pick-up roller 44 sends out a plurality of sheets S to the outside of the cassette 31, the separation roller 46 returns the sheet except the uppermost sheet to the cassette 31. It will be sent downstream one by one.

  A guide wall 46 that curves upward toward the right is formed downstream of the paper feed roller 45. A first transport roller 47 is disposed above the guide wall 46. The 1st conveyance roller 47 is contained in the drawer unit 10 mentioned later. The first transport roller 47 is disposed adjacent to a surface opposite to the surface of the second transport wall 435 facing the first transport wall 434. The second transport roller 48 contacts the first transport roller 47. The second conveyance roller 48 rotates together with the first conveyance roller 47. The second transport roller 48 is included in the transport unit 20. The first transport roller 47 and the second transport roller 48 are disposed in the second transport path 49 along the second direction from the bottom to the top. The first conveyance path 43 and the second conveyance path 49 formed so as to be able to guide the sheet S merge at the upper end of the second conveyance wall 435 to form a merge conveyance path 50.

  The merged conveyance path 50 extends upward, and a registration roller pair 51, an image forming unit 52, a fixing unit 53, and a discharge unit 54 are disposed in the middle of the merged conveyance path 50. The registration roller pair 51 is disposed in the vicinity of the lower end portion of the merging conveyance path 50. The registration roller pair 51 sends the sheet S to the image forming unit 52 in synchronization with the timing of image formation by the image forming unit 52. The registration roller pair 51 includes a first registration roller 511 attached to the inner wall (first conveyance wall 434) of the housing 2 and a second registration roller 512 attached to the conveyance unit 20. The first registration roller 511 and the second registration roller 512 convey the sheet S upward while sandwiching the sheet S.

  The image forming unit 52 forms a toner image on the sheet S sent through one of the first conveyance path 43 and the second conveyance path 49. In the housing 2, a magenta unit 52M that forms a toner image with magenta toner, a cyan unit 52C that forms a toner image with cyan toner, and a yellow unit that forms a toner image with yellow toner A black unit 52K for forming a toner image with 52Y and black toner is disposed. The magenta unit 52M, the cyan unit 52C, the yellow unit 52Y, and the black unit 52K are sequentially arranged from the left to the right.

  Each of the units 52M, 52C, 52Y, and 52K includes a photosensitive drum 521 and a developing device 522 that supplies toner to the photosensitive drum 521. After an electrostatic latent image is formed on the peripheral surface of the photosensitive drum 521, toner is supplied from the developing device 522, and a toner image (visible image) corresponding to the electrostatic latent image is formed.

  The photosensitive drum 521 in FIG. 1 rotates clockwise. The toner image formed on the photosensitive drum 521 is transferred to an intermediate transfer belt 525 that moves above the photosensitive drum 521.

  Four toner cartridges 520 that respectively accommodate magenta toner, cyan toner, yellow toner, and black toner are detachably attached to the housing 2. These toner cartridges 520 are positioned between the intermediate transfer belt 525 and the upper wall 21 of the housing 2 formed to be capable of supporting the sheet S discharged from the discharge portion 54. A toner supply duct (not shown) extends from each toner cartridge 520 toward each unit 52M, 52C, 52Y, 52K, and toner is supplied to each unit 52M, 52C, 52Y, 52K.

  The image forming unit 52 further includes a charging device 523 provided below the photosensitive drum 521 of each unit 52M, 52C, 52Y, 52K, and an exposure device 524 provided below the charging device 523. The charging device 523 uniformly charges the peripheral surface of the photosensitive drum 521. The exposure device 524 irradiates the peripheral surface of the charged photosensitive drum 521 with laser light based on the received digital signal relating to the image data. As a result, an electrostatic latent image corresponding to each color component of the original is formed on the peripheral surface of the photosensitive drum 521 of each unit 52M, 52C, 52Y, 52K. Thereafter, the developing device 522 supplies toner to the peripheral surface of the photoconductive drum 521, and the toner electrostatically adheres to the electrostatic latent image to form a toner image.

  The intermediate transfer belt 525 above each photosensitive drum 521 extends between a right driving roller 525a and a left driven roller 525b. The lower surface of the intermediate transfer belt 525 (moving to the right) located on the lower side is in contact with the peripheral surface of each photosensitive drum 521. The outer peripheral surface of the intermediate transfer belt 525 is used as a surface for carrying toner. A transfer roller 526 is disposed above each photosensitive drum 521. The intermediate transfer belt 525 circulates between the driving roller 525a and the driven roller 525b while being pressed against the peripheral surface of the photosensitive drum 521 by the transfer roller 526. A tension roller 525c is disposed between the driving roller 525a and the driven roller 525b. The tension roller 525c is biased upward by a biasing member (not shown), for example. The tension roller 525c pushed upward by the urging member creates an outline of the mountain-shaped intermediate transfer belt 525 protruding upward near the driven roller 525b, and generates tension on the intermediate transfer belt 525.

  During the rotation of the intermediate transfer belt 525, the photosensitive drum 521 of the magenta unit 52M transfers the toner image of the magenta toner to the intermediate transfer belt 525. Thereafter, the cyan unit 52C transfers the cyan toner image onto the magenta toner image. Thereafter, the yellow unit 52Y transfers the toner image of the yellow toner onto the toner image formed by superimposing the magenta toner and the cyan toner. Finally, the black unit 52K transfers the black toner image onto the toner image formed by superimposing the magenta toner, the cyan toner, and the yellow toner, thereby completing a full-color toner image. The full color toner image completed on the intermediate transfer belt 525 is transferred to the sheet S conveyed from the storage unit 3.

  The sheet S guided and conveyed by the merge conveyance path 50 extending in the vertical direction on the left side of the image forming unit 52 is directed to the secondary transfer nip formed by the second transfer roller 513 and the intermediate transfer belt 525. The merge conveyance path 50 includes a second transfer roller 513. The second transfer roller 513 is opposed to the drive roller 525a around which the intermediate transfer belt 525 is wound, and abuts on the outer peripheral surface of the intermediate transfer belt 525 to form a secondary transfer nip portion. The sheet S guided to the merging conveyance path 50 and sent to the secondary transfer nip portion between the intermediate transfer belt 525 and the second transfer roller 513 is pressed and nipped by the intermediate transfer belt 525 and the second transfer roller 513. The full color toner image completed on the intermediate transfer belt 525 is transferred to the sheet S.

  The image forming apparatus 1 further includes a cleaning device 528. The cleaning device 528 removes the toner remaining on the intermediate transfer belt 525 after the transfer of the toner image onto the sheet S (generally referred to as secondary transfer), and cleans the intermediate transfer belt 525. The cleaning device 528 is disposed to face the driven roller 525b.

  The fixing unit 53 performs a fixing process on the toner image transferred onto the sheet S by the image forming unit 52. The fixing unit 53 includes a heating roller 531 and a pressure roller 532 disposed to face the heating roller 531. The heating roller 531 incorporates an energization heating element used as a heating source.

  The sheet S carrying the toner image is conveyed to the fixing unit 53. While the sheet S passes between the pressure roller 532 and the high-temperature heating roller 531, the toner image receives heat from the heating roller 531 and is fixed to the sheet S.

  Fixing processing by the fixing unit 53 is completed, and color printing ends. The sheet S on which color printing has been applied is guided to the merging conveyance path 50 extending upward from the fixing unit 53 and is discharged from the discharge unit 54. The upper surface (upper wall 21) of the housing 2 is used as a paper discharge tray that supports the sheet S on which color printing has been applied.

  The relay device 60 is disposed along the front wall of the housing 2 in the housing 2. The upper surface of the relay device 60 is formed to be able to support the front end of each toner cartridge 520. Components of the image forming apparatus (photosensitive drum 521, intermediate transfer belt 525, developing device 522, charging device 523) are disposed on the back side of the relay device 60. The relay device 60 guides the toner supplied from the toner cartridge 520 toward each developing device 522 disposed below the intermediate transfer belt 525.

  The relay device 60 further serves to store waste toner generated after the transfer process. A cleaning device 527 is disposed on the left side of each photosensitive drum 521. The cleaning device 527 removes toner remaining on the peripheral surface of the photosensitive drum 521 after the transfer of the toner image to the intermediate transfer belt 525 (referred to as primary transfer), and the removed toner is used as waste toner. It is accommodated in the relay device 60. The peripheral surface of the photosensitive drum 521 cleaned by the cleaning device 527 is directed to the charging device 523 and is newly charged. A cleaning device 528 is disposed on the right side of the intermediate transfer belt 525 so as to face the driven roller 525b. The cleaning device 528 removes the toner remaining on the outer peripheral surface of the intermediate transfer belt 525 that has finished transferring the toner image to the sheet S (referred to as secondary transfer), and the removed toner is relayed as waste toner. Housed in device 60. Thereafter, the outer peripheral surface of the intermediate transfer belt 525 cleaned by the cleaning device 528 receives a new toner image transferred from each photosensitive drum 521.

  Please refer to FIG. 1 again. The image forming apparatus 10 shown in FIG. 1 can print on both sides of the sheet S. The sheet S subjected to the image fixing process on one surface by the fixing unit 53 is directed to the discharge roller pair 541 provided in the discharge unit 54. When printing of only one side is instructed, the sheet S is discharged onto the upper wall 21 of the housing 2 as it is. On the other hand, when printing on both sides is instructed, the discharge roller pair 541 rotates reversely so that the sheet S is discharged out of the casing 2 by a predetermined amount and then pulled back into the casing 2 again. Thereafter, the sheet S is fed into a third conveyance path 55 that extends downward along the right surface of the housing 2. A pair of conveyance rollers 551 for conveying the sheet S is disposed at an appropriate position on the third conveyance path 55. The third conveyance path 55 is curved so as to surround the right surface and the lower surface of the conveyance unit 20, and merges with the second conveyance path 49 immediately before the nip portion formed by the first conveyance roller 47 and the second conveyance roller 48. Accordingly, the sheet S sent to the third transport path 55 is sent again to the registration roller pair 51 by the first transport roller 47 and the second transport roller 48. Thereafter, the registration roller pair 51 sends the sheet S to the image forming unit 52 in synchronization with the image forming timing of the image forming unit 52. The image forming unit 52 forms an image on the blank surface (the surface on which printing is not performed) of the sheet S. Thereafter, the new toner image is fixed on the sheet S by the fixing unit 53 and discharged onto the upper wall 21 of the housing 2 by the discharge roller 541.

  FIG. 2 is a perspective view of the drawer unit 10. The drawer unit 10 will be described with reference to FIG. 1 in conjunction with FIG.

  The drawer unit 10 includes a substantially triangular prism-shaped casing 101, and a first transport roller 47 is disposed along the top of the casing 101. The surface formed on the opposite side to the first transport roller 47 is the above-described second transport wall 435. A gear 471 is disposed at the right end of the first transport roller 47. When the drawer unit 10 is accommodated in the housing 2 of the image forming apparatus 1, the gear 471 meshes with a gear connected to a drive source (not shown) disposed in the housing 2 of the image forming apparatus 1. The driving force is transmitted. The second transport roller 48 attached to the transport unit 20 is pressed against the first transport roller 47 and rotates together with the first transport roller 47.

  A total of four connecting pieces 102 protrude from both side surfaces of the drawer unit 10. The connection piece 102 plays a role of supporting the drawer unit 10 in the housing 2 of the image forming apparatus 1 and is pulled out while the drawer unit 10 is pushed into the housing 2 and while the drawer unit 10 is pulled out from the housing 2. It plays a role of guiding the unit 10. Therefore, it is preferable that the connection piece 102 is rotatably attached to the housing 101. In FIG. 2, the connection piece 102 located on the upper side is referred to as the first connection piece 102a for the sake of convenience below, and the connection piece 102 located on the lower side is referred to as the second connection piece 102b for the sake of convenience. The

  The drawer unit 10 further includes projecting pieces 103 disposed on the left and right sides of the housing 101. While the drawer unit 10 is housed in the housing 2 of the image forming apparatus 1, the protruding piece 103 protrudes toward the transport unit 20.

  Please refer to FIG. 1 again. A cover 22 forming the right surface of the housing 2 of the image forming apparatus 1 shown in FIG. 1 has a rotation axis along the lower edge and can be rotated up and down. When the cover 22 is rotated downward, the transport unit 20 is exposed. At this time, the sheet S present in the third conveyance path 55 is removed relatively easily.

  FIG. 3 is a perspective view showing the transport unit 20 and the drawer unit 10 pulled out from the housing 2 of the image forming apparatus 1. The transport unit 20 and the drawer unit 10 will be described with reference to FIG. 1 in conjunction with FIG. The positions of the transport unit 20 and the drawer unit 10 shown in FIG. 1 are referred to as a first position for convenience, and the positions of the transport unit 20 and the drawer unit 10 shown in FIG. 3 are referred to as a second position for convenience. Is done.

  The drawer unit 10 and the transport unit 20 are supported in the housing 2 by a front wall (not shown) and a back wall 23 of the housing 2. In the present embodiment, the front wall and the rear wall 23 of the housing 2 are used as support walls for supporting the drawer unit 10 and the transport unit 20, but the present invention is not limited to this, The left and right walls may be used as support walls. Although the front wall is not shown in FIG. 3, the structure, shape and elements of the back wall 23 for supporting the drawer unit 10 and the transport unit 20 are symmetrical to the front wall unless otherwise specified. Is provided.

  As described above, when the cover 22 is rotated downward from the housing 2 of the image forming apparatus 1, the transport unit 20 is exposed. The transport unit 20 includes a substantially rectangular parallelepiped housing 201, and a rotation shaft 202 is formed at the lower end of the side surface of the housing 201. The rotation shaft 202 rotatably supports the transport unit on the back wall 23 and the front wall. After the cover 22 is pivoted downward, the transport unit 20 can pivot downward about the pivot shaft 202. When the transport unit 20 is rotated downward and moved toward the second position, the second transport roller 48 of the transport unit 20 is separated from the first transport roller 47 of the drawer unit 10. When the transport unit 20 is rotated toward the second position, the drawer unit 10 can move such that the second transport wall 435 is separated from the first transport wall 434.

  When the drawer unit 10 is completely pulled out, the protruding piece 103 of the drawer unit 10 contacts the side edge of the transport surface 203 of the transport unit 20 that forms the second transport path 49 and the merged transport path 50. Due to the contact between the conveyance surface 203 and the protruding piece 103, the first conveyance roller 47 is kept away from the conveyance surface 203, and damage to the first conveyance roller 47 is prevented.

  A rail portion 231 is attached to the inner surfaces of the back wall 23 and the front wall. The rail portion 231 defines the drawing path of the drawing unit 10. The rail portion 231 supports the first connection piece 102a and guides the movement of the first connection piece 102a. The rail portion 231 supports the second connection piece 102b and guides the movement of the second connection piece 102b. 2nd rail part 231b.

  FIG. 4 is a diagram schematically showing the first rail portion 231a. The first rail portion 231a will be described with reference to FIG. 3 in conjunction with FIG.

  The first rail portion 231a includes a first section that is inclined upward toward the right. The first section extends between a first end located inside the housing 2 of the image forming apparatus 1 and a second end located above the first end and outside the housing 2. The first rail portion 231a further includes a second section extending downward from the second end. The second section extends between the second end and a third end located below the second end and located outside the housing 2.

  The first rail portion 231a is closed at the first end and the third end of the first rail portion 231a. Therefore, the movement of the first connection piece 102a in the first rail portion 231a is stopped at the first end and the third end. As a result, the drawer unit 10 in the first position and the drawer unit 10 in the second position are each stably supported by the first end and the third end of the first rail portion 231a. The second rail portion 231b is formed so as to be adapted to the movement of the second connection piece 102b according to the movement of the first connection piece 102a in the first rail portion 231a.

  5 to 7 are perspective views showing the drawer unit 10 housed in the housing 2 of the image forming apparatus 1. FIG. 5 shows the drawer unit 10 in the first position, and FIG. 7 shows the drawer unit 10 in the second position. FIG. 6 shows the drawer unit 10 in the middle of moving from the first position to the second position or in the middle of moving from the second position to the first position. The movement of the drawer unit 10 will be described with reference to FIGS. 1, 3, and 4 in conjunction with FIGS.

  As shown in FIGS. 5 to 7, the user can expose the drawer unit 10 by rotating the transport unit 20 downward. As a result, the sheet S existing in the second conveyance path 49 can be easily taken out. When the user pulls the drawer unit 10 outward of the housing 2, the drawer unit 10 is guided by the rail portion 231 and moves toward the outside of the housing 2. While the 1st connection piece 102a exists in the 1st area of the 1st rail part 231a, the drawer unit 10 moves diagonally upward toward a user. When the first connection piece 102a reaches the second end of the first rail portion 231a, the user can loosen the force applied to the drawer unit 10. As a result, the first connection piece 102a moves to the third end of the first rail portion 231a, and the drawer unit 10 is stably supported at the second position. While the drawer unit 10 is in the second position, the first transfer wall 434 and the second transfer wall 435 are sufficiently separated from each other, and thus formed between the first transfer wall 434 and the second transfer wall 435. The removal of the sheet S in the first conveyance path 43 is facilitated.

  The user pulls the drawer unit 10 upward so that the first connection piece 102a moves from the third end of the second section of the first rail portion 231a to the second end, and then applies a force to the drawer unit 10. By loosening, the drawer unit 10 is drawn into the housing 2 and reaches the first position. Thus, the drawer unit 10 can be easily accommodated in the housing 2.

  As shown in FIG. 4, the first rail portion 231 a is inclined upward toward the inside of the housing 2 of the image forming apparatus 1. Therefore, when the transport unit 20 located at the second position shown in FIG. 3 is rotated upward, the first connection piece 102a moves along the second section of the first rail portion 231a, and then the first rail. The portion 231a moves from the second end of the first section toward the first end. As a result, the transport unit 20 reaches the first position. Therefore, the drawer unit 10 can be accommodated in the housing 2 by rotating the transport unit 20 upward. Thereafter, by rotating the cover 22 upward, the third transport path 55 is formed between the transport unit 20 and the cover 22, and preparation for the image forming process is completed.

  This embodiment is suitably applied to an image forming apparatus that forms an image on a sheet.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus 10 ... Drawer unit 102 ... Connection piece 103 ... Projection piece 2 ... Case 23 ... Back wall 231 ... rail part 231a ... first rail part 20 ... transport unit 43 ... first transport path 434 ... ... first transport wall 435 ... ... second transport wall 47... First transport roller 48... Second transport roller 49... Second transport path 52.

Claims (5)

An image forming unit for forming an image on a sheet;
A first conveying wall that defines a conveying direction of the sheet;
A second conveying wall disposed opposite the first conveying wall and defining the conveying direction together with the first conveying wall; and a surface opposite to the surface of the second conveying wall facing the first conveying wall. A drawer unit including a first conveying roller disposed adjacent to
A conveyance unit comprising a second conveyance roller that contacts the first conveyance roller and rotates together with the first conveyance roller;
The first transport wall and the second transport wall form a first transport path formed so that the sheet can be guided,
The first transport roller and the second transport roller are disposed in a second transport path that merges with the first transport path,
The sheet is conveyed to the image forming unit through at least one of the first conveyance path and the second conveyance path,
The conveyance unit includes a first position where the second conveyance roller forms the second conveyance path together with the first conveyance roller, and a second position where the second conveyance roller is separated from the first conveyance roller. Is movable,
The image forming apparatus, wherein when the transport unit is at the second position, the drawer unit can be pulled out such that the second transport wall is separated from the first transport wall. A housing including a support wall for supporting the drawer unit;
The support wall includes a rail portion that defines a drawer path of the drawer unit;
The drawer unit further includes a connection piece that is connected to the rail portion and moves along the rail portion,
The rail portion includes a first section extending between a first end and a second end located above the first end and outward of the housing, the second end, and the second end. The image forming apparatus according to claim 1, further comprising a second section extending between a third end located below. The support wall supports the transport unit so as to be rotatable up and down between the first position and the second position,
When the transport unit is rotated upward from the second position toward the first position, the drawer unit is pushed up, and the connecting piece moves from the second section to the first section. The image forming apparatus according to claim 2. The drawer unit further includes a protruding piece protruding in the direction of the transport unit,
The image forming apparatus according to claim 3, wherein the protruding piece separates the first transport roller from the transport unit when the pull-out unit is pulled out.   The image forming apparatus according to claim 3, wherein the first end and the third end are formed so as to stop the movement of the connection piece.

Images