Image forming apparatus

Abstract

The present disclosure relates to an image forming apparatus including: a housing configured to accommodate an image forming unit that forms an image on a recording material; a discharge unit configured to discharge the recording material to an outside of the housing; and a motor disposed inside the housing and configured to drive the image forming unit. And a housing including a stacking unit on which the recording material discharged by the discharge unit is stacked, and a wall surface provided at an end portion of the stacking unit in a width direction perpendicular to a vertical direction and a discharge direction of the discharge unit, and the wall surface extends upwards beyond the stacking unit. The motor is disposed at a position overlapping the wall surface when viewed in the width direction.

Description

Technical Field

[0001] The present disclosure relates to an image forming apparatus that forms an image on a recording medium. Background Art

[0002] Japanese Patent Laid-Open No. 2016-45375 describes an image forming apparatus including a motor mounted on a side plate of the image forming apparatus and a gear train that transmits a driving force of the motor to a photosensitive drum. Summary of the invention

[0003] It is necessary to determine a motor mounting position that achieves further size reduction of the image forming apparatus.

[0004] Therefore, the present disclosure provides an imaging device that can be reduced in size. According to one aspect of the present disclosure, an imaging device includes: a housing configured to accommodate an imaging unit that forms an image on a recording material; a discharge unit that includes a roller and is configured to discharge the recording material to the outside of the housing; and a motor that is arranged inside the housing and is configured to drive the imaging unit, wherein the housing includes a stacking unit and a wall surface, the recording material discharged by the discharge unit is stacked on the stacking unit, the wall surface is arranged at an end of the stacking unit in a width direction, the width direction is perpendicular to both the vertical direction and the discharge direction of the discharge unit, and the wall surface extends upward beyond the stacking unit, and wherein the motor is arranged at a position overlapping with the wall surface when viewed along the width direction.

[0005] Further features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is a schematic diagram of an imaging apparatus according to a first embodiment.

[0007] Figure 2 is a perspective view of the imaging apparatus according to the first embodiment.

[0008] Figure 3 is an exploded view of a housing frame according to the first embodiment.

[0009] Figure 4A is a perspective view of the cartridge according to the first embodiment.

[0010] Figure 4B A motor according to a first embodiment is shown.

[0011] Figure 5 A motor according to a first embodiment is shown.

[0012] Figure 6A motor according to a first embodiment is shown.

[0013] Figure 7 A motor according to a first embodiment is shown.

[0014] Figure 8 A motor according to a first embodiment is shown.

[0015] Fig. 9 A motor and a drive transmission mechanism according to a first embodiment are shown.

[0016] Fig. 10A A motor according to a second embodiment is shown.

[0017] Fig. 10B A motor according to a second embodiment is shown.

[0018] Fig.11 is a schematic diagram of an imaging apparatus according to a third embodiment. DETAILED DESCRIPTION

[0019] Exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings.

[0020] In the following description and drawings, the vertical direction (gravity direction) when the image forming apparatus is installed on a horizontal surface is defined as the Z-axis direction. The direction of the rotation axis of the photosensitive drum (image bearing member) of the image forming apparatus is defined as the Y-axis direction, and the direction intersecting both the Z-axis direction and the Y-axis direction is defined as the X-axis direction.

[0021] The X-axis direction, the Y-axis direction, and the Z-axis direction are preferably perpendicular to each other.

[0022] The positive direction and negative direction along each coordinate axis are indicated by adding a + (positive) or - (negative) sign to the direction, respectively, as required. For example, the positive direction of the X axis (the direction indicated by the arrow X in the figure) indicates the +X side, and the negative direction of the X axis (the opposite side of the arrow X) indicates the -X side.

[0023] First embodiment

[0024] Figure 1 is a schematic diagram of an imaging apparatus 100 according to the first embodiment. Figure 1 A cross section of the imaging device 100 cut through an XZ plane is shown. Figure 2 is a perspective view of the imaging apparatus 100 .

[0025] The image forming apparatus 100 forms an image on a sheet S which is a recording material (recording medium) based on image information received from, for example, an external information processing apparatus. The image forming apparatus 100 is an electrophotographic monochrome image forming apparatus which is a laser beam printer. As the sheet S, sheet materials of various sizes and materials can be used. Examples of the sheet S include paper (e.g., plain paper or thick paper), surface-treated sheet materials (e.g., coated paper), special-shaped sheet materials (e.g., envelopes or index paper), plastic films, and cloth.

[0026] Imaging equipment

[0027] like Figure 1 As shown, the image forming apparatus 100 includes an apparatus body 101 (which is the main body of the image forming apparatus), a process cartridge 10 that can be removed from the apparatus body 101, and a sheet tray 21. The apparatus body 101 includes a housing 102 and constituent elements attached to the housing 102. The housing 102 includes at least one frame member that forms a frame of the image forming apparatus 100 (a frame of the apparatus body 101) and at least one cover member (external member) that forms an outer surface of the image forming apparatus 100 (an outer surface of the apparatus body 101).

[0028] The process cartridge 10 is an example of an image forming unit that forms an image on a recording material.

[0029] The process cartridge 10 is a process unit for forming an image on a recording material by an electrophotographic process. The process cartridge 10 according to the present embodiment can be removed from a housing 102. That is, the housing 102 can accommodate the process cartridge 10 serving as an image forming unit for forming an image on a recording material.

[0030] The housing 102 includes an opening portion and an opening and closing cover 102C serving as an opening and closing member that can open and close the opening portion. With the opening and closing cover 102C open, the process cartridge 10 can be removably mounted to the housing 102 through the opening portion.

[0031] like Figure 1 As shown, the apparatus body 101 includes a feed unit 22, a conveying roller pair 23 and 24, a transfer roller 25, a fixing device 26, and a discharge roller pair 29. These constituent elements are attached to a housing 102. In addition, a discharge tray 30 and a side wall 30a (also referred to as the discharge tray 30) are provided at the upper portion of the apparatus body 101 (the upper portion of the housing 102). Figure 2 ). The discharge tray 30 and the side wall 30 a are part of the housing 102 .

[0032] The discharge roller pair 29 is an example of a discharge unit that discharges the sheet S from the inside of the apparatus body 101 to the outside (discharges from the inside of the housing 102 to the outside). The discharge roller pair 29 according to the present embodiment discharges the sheet S toward a discharge direction D1 that intersects both the Y-axis direction and the Z-axis direction. The housing 102 has a discharge port that is an opening that allows the sheet S discharged by the discharge roller pair 29 to pass therethrough.

[0033] In the following description, the downstream side in the discharge direction D1 (+X side in the X-axis direction) is the “front side” of the image forming apparatus 100, and the opposite side (−X side) is the rear side of the image forming apparatus 100. When the image forming apparatus 100 is viewed from the front side (+X side), the right side (+Y side in the Y-axis direction) is the “right side” of the image forming apparatus 100, and the opposite side (−Y side) is the “left side” of the image forming apparatus 100.

[0034] The process cartridge 10 is formed by assembling a photosensitive drum 1 serving as an image bearing member and at least one of the process units acting on the photosensitive drum 1 to perform an electrophotographic process (charging, exposure, development, transfer, cleaning, and pre-exposure) into a unit. The process cartridge 10 according to the present embodiment includes a charging roller 43 serving as a process unit (charging unit), a developing unit 40 serving as a process unit (developing unit), and a cleaning member serving as a process unit (cleaning unit).

[0035] The photosensitive drum 1 is an electrophotographic photosensitive member molded into a cylindrical shape (drum shape). The developing unit 40 includes a developing roller 41 that carries a toner used as a developer and supplies the toner to the photosensitive drum 1, and a developing frame 46 (developing container) that supports the developing roller 41. A toner storage portion (toner storage chamber) that stores the toner is provided inside the developing frame 46. The process cartridge 10 also includes a cleaning frame 42 that supports the photosensitive drum 1, the charging roller 43, and the cleaning member.

[0036] Roughly speaking, the process cartridge 10 is divided into a photosensitive member unit and a developing unit 40, the photosensitive member unit including the photosensitive drum 1, the charging roller 43, the cleaning member, and the cleaning frame 42. The cleaning frame 42 is a frame of the photosensitive member unit. A space (exposure opening) that allows the laser beam L from the laser scanner 11 to pass is formed between the cleaning frame 42 and the developing frame 46. The cleaning frame 42 and the developing frame 46 are connected to each other via side covers 10a and 10b ( Figure 4A ) are connected to each other.

[0037] The sheet tray 21 has a stacking area in which sheets S are stacked. The sheet tray 21 is a storage portion (storage, sheet box) for storing sheets S. The sheet tray 21 is arranged in the lower portion of the apparatus main body 101, and is configured to be insertable into and withdrawn from the apparatus main body 101 (insertable into and withdrawn from the housing 102). The sheet tray 21 according to the present embodiment can be moved in the X-axis direction relative to the apparatus main body 101 so as to be pulled out from the apparatus main body 101 toward the front side (+X side) of the imaging apparatus 100, and inserted into the apparatus main body 101 toward the rear side (-X side) of the imaging apparatus 100.

[0038] The feeding unit 22 is an example of a feeding unit that feeds the sheets S one by one. The feeding unit 22 includes, for example, a feeding roller (pick-up roller) that feeds the sheets S from the sheet tray 21 and a separation roller pair that separates the plurality of sheets S into a single sheet S and conveys the sheet S when the plurality of sheets S are fed by the feeding roller.

[0039] The transport roller pairs 23 and 24 are each a transport member that transports the sheet S. The transport roller pairs 23 and 24 are arranged in a sheet transport path from the feeding unit 22 to a transfer portion Nt (described below).

[0040] The laser scanner 11 is an example of a process unit (exposure unit, exposure device). When the process cartridge 10 is installed in the apparatus main body 101, the laser scanner 11 is arranged above the process cartridge 10 so as to overlap with the process cartridge 10 when viewed in the Z-axis direction. The laser scanner 11 includes an oscillator that emits a laser beam L and an optical system (e.g., a polygon mirror) that guides the laser beam L to the photosensitive drum 1 and scans the photosensitive drum 1 in the main scanning direction (X-axis direction). Instead of the laser scanner 11, an LED exposure device including light emitting elements (LEDs) arranged in the main scanning direction (X-axis direction) may be used.

[0041] According to the present disclosure, the expression "two elements 'overlap' when viewed in a predetermined direction" means that when each element is vertically projected onto an imaginary plane perpendicular to the predetermined direction, a projection area of ​​one element at least partially overlaps with a projection area of ​​another element. Unless otherwise specified, the meaning of this expression includes the case where the two elements overlap in a transparent view when another element exists between the two elements in a predetermined direction.

[0042] The transfer roller 25 is an example of a process unit (transfer unit). When the process cartridge 10 is installed in the apparatus body 101, the transfer roller 25 is arranged to contact the photosensitive drum 1. As a nip portion between the photosensitive drum 1 and the transfer roller 25, a transfer portion Nt is formed where the toner image is transferred onto the sheet S. The transfer roller 25 is an example of a transfer member. For example, a corona discharge transfer member can be used.

[0043] The fixing device 26 is a fixing unit that fixes the toner image onto the sheet S. The fixing device 26 is a thermal fixing device (image heating device) that fixes the toner image onto the sheet S by heating the toner image while conveying the sheet S in the fixing portion Nf.

[0044] The fixing device 26 according to the present embodiment is of a film heating type, and uses a cylindrical film (fixing film 28) as a heating member (fixing member) to heat the toner image. The fixing device 26 includes a fixing film 28, a heater serving as a heating unit for heating the fixing film 28, and a pressure roller 27 serving as a pressure member that forms a fixing portion Nf together with the fixing film 28. The heater is, for example, a ceramic heater having a pattern of a heating resistor printed on a ceramic substrate, and is arranged in the internal space of the fixing film 28 while being held by a heater holder. The pressure roller 27 is arranged to sandwich the fixing film 28 together with the heater and the heater holder. At least one of the pair consisting of the heater and the heater holder and the pressure roller 27 is pushed against the other, and thus, pressure (nip pressure) is generated in the fixing portion.

[0045] According to the present embodiment, the pressure roller 27 is a driven member that rotates by receiving a driving force from a motor 61 (described below). During image formation, the fixing film 28 receives a force from the pressure roller 27 and rotates with the pressure roller 27 .

[0046] The fixing device 26 described above is an example of a fixing unit, and a fixing unit having other configurations may be employed. For example, a roller member (fixing roller) having high rigidity may be used as a heating member (fixing member). The heating member (fixing member) or the pressure member may be a belt stretched around a plurality of rollers. The driven member that rotates by receiving the driving force from the motor 61 may be a roller of a fixing roller or a driving belt. The heating unit for heating the heating member (fixing member) may be a halogen lamp that emits radiant heat or a coil unit that generates heat in a conductive layer in the heating member (fixing member) by the principle of induction heating.

[0047] Imaging Operation

[0048] Reference below Figure 1 The image forming operation performed by the image forming apparatus 100 is described. The image forming operation is a series of operations performed based on an execution instruction from a user, in which the image forming apparatus 100 conveys sheets S one by one, forms images on the sheets S based on image information, and discharges the sheets S onto the discharge tray 30 .

[0049] In the image forming operation, the sheets S stored in the sheet tray 21 are fed one by one by the feeding unit 22 , and the sheets S are conveyed to the transfer portion Nt by the conveying roller pairs 23 and 24 .

[0050] The transport roller pair 24 immediately before the transfer portion Nt functions as an alignment unit that adjusts the transport timing of the sheet S to match the timing at which the toner image formed on the photosensitive drum 1 reaches the transfer portion Nt.

[0051] In the process unit (processing box 10), the photosensitive drum 1 is Figure 1 The photosensitive drum 1 is driven in the clockwise direction. The charging roller 43 uniformly charges the surface of the photosensitive drum 1 to a predetermined polarity and a predetermined potential. The laser scanner 11 emits a laser beam L to expose the photosensitive drum 1 and forms an electrostatic latent image corresponding to the image information on the surface of the photosensitive drum 1. The developing roller 41 supplies a toner serving as a developer to the photosensitive drum 1 to develop the electrostatic latent image into a toner image. The toner image formed on the photosensitive drum 1 is carried on the photosensitive drum 1 and reaches the transfer portion Nt.

[0052] Then, in the transfer portion Nt, the toner image is transferred from the photosensitive drum 1 to the sheet S. Foreign matter (e.g., residual transfer toner remaining on the photosensitive drum 1 without being transferred to the sheet S in the transfer portion Nt) is collected by the cleaning member and stored in the waste toner storage portion inside the cleaning frame 42 .

[0053] The sheet S that has passed through the transfer section Nt is conveyed to the fixing device 26. While the sheet S is clamped and conveyed in the fixing section Nf, the fixing device 26 heats the toner image on the sheet S using the fixing film 28 heated by the heater. The toner on the sheet S is heated and pressurized to produce an image fixed to the sheet S. The sheet S that has passed through the fixing device 26 is discharged to the outside of the apparatus body 101 (outside the housing 102) along the discharge direction D1 by the discharge roller pair 29, and is stacked on the discharge tray 30.

[0054] Configuration of top surface portion of housing

[0055] Reference below Figure 2 The discharge tray 30 and the side walls 30a and 30b provided on the top surface portion of the housing 102 are described. Figure 2 As shown, the discharge tray 30 and the side walls 30 a and 30 b are provided in a top surface portion of the housing 102 (apparatus main body 101 ).

[0056] The discharge tray 30 is a stacking unit on which sheets S (deliverables) each having an image formed thereon by the image forming apparatus 100 are stacked. When viewed along the width direction (Y-axis direction) perpendicular to both the vertical direction (Z-axis direction) and the discharge direction D1 of the discharge roller pair 29, at least a portion of the discharge tray 30 is inclined upward toward the downstream side in the discharge direction D1. That is, the discharge tray 30 according to the present embodiment has an inclined surface that is inclined downward toward the discharge roller pair 29 relative to the top surface 102u (+Z side end surface) of the housing 102.

[0057] The side wall 30a is a wall surface that is provided at one end portion (+Y side, right side) of the discharge tray 30 in the width direction (Y-axis direction) and extends upward beyond the discharge tray 30. The side wall 30b is a wall surface that is provided at the other end portion (-Y side, left side) of the discharge tray 30 in the width direction (Y-axis direction) and extends upward beyond the discharge tray 30. When viewed from above, the side walls 30a and 30b extend in the discharge direction D1. The upper end of each of the side walls 30a and 30b is connected to the top surface 102u of the housing 102.

[0058] The side walls 30 a and 30 b reduce movement of the sheet S discharged onto the discharge tray 30 in the width direction (Y-axis direction), and thus reduce disruption of the alignment of the sheet S. The distance between the side walls 30 a and 30 b in the width direction (Y-axis direction) is set to be slightly larger than the size of the largest sheet S in the width direction (Y-axis direction) among various types of sheets S on which the image forming apparatus 100 can form an image.

[0059] Shell frame structure

[0060] Next, the frame construction of the housing 102 will be described. Figure 3 1 is an exploded view of a portion of the device body 101. More specifically, Figure 3 There are shown frame members (51, 52, 53, 54, 55, 57) of the housing 102 of the apparatus body 101, the motor 61, the laser scanner 11, and the guide member 59. Each of the frame members is made of a metal plate (eg, a stainless steel plate).

[0061] The housing 102 according to the present embodiment includes a front scanner bracket 51, a rear scanner bracket 52, a transfer conveying frame 53, side plates 54 and 55, and a rear bracket 57. The frame members (51, 52, 53, 54, 55, 57) constitute a frame having a substantially rectangular parallelepiped shape. In addition, the frame and an external member (cover member) covering the frame constitute the housing 102. An installation space (installation portion) is formed inside the frame, and the process cartridge 10 is installed in the installation space.

[0062] The side plates 54 and 55 are a pair of plate-like frame members that face each other in the width direction (Y-axis direction) of the image forming apparatus 100 and intersect the width direction (Y-axis direction). The front scanner support 51, the rear scanner support 52, the transfer conveying frame 53, and the rear support 57 each extend in the width direction (Y-axis direction) and are connected to each of the side plates 54 and 55 forming a pair. The side plate 54 is an example of a first side plate, and the side plate 55 is an example of a second side plate. The front scanner support 51 is an example of a first frame, and the rear scanner support 52 is an example of a second frame.

[0063] The front scanner support 51 and the rear scanner support 52 hold the laser scanner 11 .

[0064] When the process cartridge 10 is installed in the apparatus main body 101, at least one of the front scanner support 51 and the rear scanner support 52 may be arranged above the process cartridge 10 ( Figure 1 ).

[0065] The front scanner bracket 51 is positioned further to the front side (+X side) than the rear scanner bracket 52. The front scanner bracket 51 holds the front portion of the laser scanner 11, while the rear scanner bracket 52 holds the rear portion of the laser scanner 11. Instead of a configuration in which the laser scanner 11 is held by two frame members (the front scanner bracket 51 and the rear scanner bracket 52), the laser scanner 11 may be held by a single plate-like frame member.

[0066] The transfer conveying frame 53 holds the transfer roller 25 and includes one or more guide portions for forming a sheet conveying path in the apparatus body 101. When the process cartridge 10 is installed in the apparatus body 101, the transfer conveying frame 53 is arranged above the sheet tray 21 and below the process cartridge 10 in the Z-axis direction.

[0067] The rear bracket 57 is arranged at the rear side (−X side) end of the apparatus body 101. The rear bracket 57 is connected to the rear side (−X side) end surface of each of the side plates 54 and 55.

[0068] like Figure 5 As shown, rear bracket 57 is arranged below fixing device 26 and above sheet tray 21 in the Z-axis direction.

[0069] According to the present embodiment, as described below, the frame member holding the laser scanner 11 is divided into two parts, that is, the front scanner bracket 51 and the rear scanner bracket 52. By providing the rear bracket 57 connecting the two side plates 54 and 55 on the rear side (-X side) of the device body 101, in the configuration in which the frame member holding the laser scanner 11 is divided into two parts, the strength of the rear side (-X side) of the device body 101 can be increased. If sufficient strength is ensured according to the specific configuration of the image forming apparatus 100, a configuration not including the rear bracket 57 may be adopted.

[0070] According to the present embodiment, the front scanner support 51 and the rear scanner support 52 holding the laser scanner 11 are arranged apart from each other in the X-axis direction. That is, according to the present embodiment, the laser scanner 11 (exposure device) is arranged between two frame members (51, 52) which are arranged apart from each other in the front-rear direction (X-axis direction) of the imaging device 100. The bottom surface portion of the laser scanner 11 has a protruding portion 11b ( Figure 1 ), the protruding portion protrudes downward through the space between the front scanner bracket 51 and the rear scanner bracket 52 beyond the top surface of each of the front scanner bracket 51 and the rear scanner bracket 52 (the supporting surface supporting the laser scanner 11).

[0071] Reference below Figure 4A and Figure 4B The relationship between the protruding portion 11 b of the laser scanner 11 and the process cartridge 10 will be described. Figure 4A is a perspective view of the process cartridge 10. Figure 4B 1 is a perspective view showing a positional relationship among the process cartridge 10 , the laser scanner 11 , and a motor 61 (described below) when the process cartridge 10 is mounted in the apparatus main body 101 .

[0072] like Figure 4A As shown, the top surface portion of the process cartridge 10 has a recessed portion 44 recessed downward at a position facing the protruding portion 11 b of the laser scanner 11 .

[0073] According to the present embodiment, the recess 44 is provided on the top surface portion of the cleaning frame 42. The recess 44 has a predetermined width in the Y-axis direction and is in the form of a shallow groove extending in the mounting direction D2 in which the process cartridge 10 is mounted to the apparatus body 101.

[0074] The predetermined width is greater than the width of the protruding portion 11b of the laser scanner 11 in the Y-axis direction ( Figure 4B). When the process cartridge 10 is installed in the apparatus main body 101, the recess 44 directly faces the protruding portion 11b of the laser scanner 11 without any other member therebetween. By providing the recess 44 in the process cartridge 10, even if the gap between the process cartridge 10 and the laser scanner 11 is reduced, contact between the process cartridge 10 and the laser scanner 11 can be prevented, and therefore, the size of the image forming apparatus 100 can be further reduced.

[0075] The protruding portion 11b of the laser scanner 11 can intrude into the recess 44 of the process box 10. That is, in the Y-axis direction ( Figure 1 ), at least a portion of the protruding portion 11b of the laser scanner 11 may be located below the top surface 42u of the cleaning frame 42. However, even in a positional relationship where the protruding portion 11b does not intrude into the recess 44, the advantage of size reduction due to the reduced gap can still be obtained.

[0076] The installation direction D2 of the process cartridge 10 is the moving direction of the process cartridge 10 when the process cartridge 10 is inserted toward a predetermined installation position (position for performing an image forming operation) in the apparatus main body 101. The apparatus main body 101 includes a guide member 59 ( Figure 3 ). The guide member 59 is provided on the inner side of the side plate 54. The protruding portions 10a1 and 10a2 ( Figure 4A ) slides on the top surface of the guide member 59, thereby regulating the movement of the process cartridge 10 in the installation direction D2. In addition, the sliding of the protruding portions 10a1 and 10a2 on the top surface of the guide member 59 regulates the movement of the process cartridge 10 being removed in the opposite direction of the installation direction D2.

[0077] motor

[0078] The motor 61 included in the image forming apparatus 100 is described below. Figure 3 As shown, a motor 61 serving as a driving source is disposed in a housing 102 of the image forming apparatus 100. That is, the image forming apparatus 100 includes the motor 61. The motor 61 can rotationally drive the photosensitive drum 1 of the process cartridge 10 mounted in the apparatus body 101.

[0079] The motor 61 can drive a plurality of driving objects, including the photosensitive drum 1. The motor 61 can be the only motor provided in the imaging device 100. The motor 61 according to the present embodiment can drive the photosensitive drum 1, the pressure roller 27 of the fixing device 26, the feeding unit 22, the conveying roller pair 23 and 24, and the discharge roller pair 29. The motor 61 can also drive other driving objects according to the specific configuration of the imaging device 100. For example, if the imaging device 100 supports duplex printing and includes a reversing roller pair for reversing the sheet S and a conveying path and a conveying roller pair (re-feeding roller pair) for conveying the reversed sheet S back toward the transfer portion Nt, the motor 61 can drive these roller pairs.

[0080] The motor 61 includes a motor body 610 and a mounting base 611 ( Figure 3 ). The motor body 610 includes a stator that does not rotate relative to the mounting base 611, a rotor that can rotate relative to the stator, and a cover member that covers the stator and the rotor and forms a storage space for the stator and the rotor together with the mounting base 611. The rotation axis of the rotor is the central axis A61 of the motor 61. The mounting base 611 is a plate-shaped member for mounting the motor 61 to the housing 102. The mounting base 611 includes a circuit and a connector 612 ( Figure 6 ).

[0081] like Figure 3 As shown, the motor 61 according to the present embodiment is mounted on the side plate 54. The motor 61 is mounted on the inner surface 541 of the side plate 54 in the width direction (Y-axis direction). That is, the motor 61 is arranged on the inner side of the side plate 54 in the width direction (Y-axis direction). In other words, according to the present embodiment, the motor 61 is arranged in the area between the two side plates 54 and 55 in the width direction (Y-axis direction) as in the sheet conveying path in the process cartridge 10, the laser scanner 11, and the apparatus main body 101.

[0082] The expression “the motor 61 is arranged on the inner side of the side plate 54 in the width direction (Y-axis direction)” means that at least the motor body 610 is located on the same side of the mounting surface for the motor 61 of the side plate 54 in the width direction (Y-axis direction) as the side plate 55 (which is the other of the two side plates). As described below, according to the present embodiment, the pinion gear 61a ( Figure 8 ) (which is an output gear of the motor 61 ) may protrude outward from the side plate 54 in the width direction (Y-axis direction).

[0083] The motor 61 is arranged below the top surface 102 u of the housing 102 and above the sheet tray 21 in the vertical direction (Z-axis direction). Figure 7 In addition, the motor 61 is arranged above the transfer conveying frame 53 ( Figure 3 ).

[0084] The motor 61 is arranged between two frame members (i.e., the front scanner bracket 51 and the rear scanner bracket 52) ​​supporting the laser scanner 11. More specifically, the motor 61 is arranged between the front scanner bracket 51 and the rear scanner bracket 52 in the front-to-rear direction (X-axis direction) of the imaging device 100. When viewed along the X-axis direction, the motor 61 overlaps with at least one of the front scanner bracket 51 and the rear scanner bracket 52, and preferably overlaps with both. In addition, the motor 61 is arranged between the front scanner bracket 51 and the rear scanner bracket 52 in the installation direction D2 of the process cartridge 10. When viewed along the installation direction D2, the motor 61 is arranged to overlap with at least one (preferably both) of the front scanner bracket 51 (first frame) and the rear scanner bracket 52 (second frame).

[0085] By arranging the motor 61 at a position overlapping with the front scanner bracket 51 or the rear scanner bracket 52 when viewed in the X-axis direction or the installation direction D2, the size of the imaging device 100 can be further reduced. That is, by arranging the motor 61 on the inner side of the side plate 54 in the width direction (Y-axis direction) using the space between the front scanner bracket 51 and the rear scanner bracket 52, the size of the imaging device 100 can be further reduced.

[0086] For example, in a configuration in which the front scanner bracket 51 and the rear scanner bracket 52 are integrated into a single plate bracket, the case where the motor 61 is arranged inside the side plate 54 is discussed below.

[0087] In this case, the motor 61 is arranged above or below the plate support to ensure a space for the motor 61, and therefore, the size of the device body 101 in the vertical direction may increase. According to the present embodiment, the motor 61 can be arranged so that the position of the motor 61 in the vertical direction (Z-axis direction) overlaps the positions of the front scanner support 51 and the rear scanner support 52 in the vertical direction (Z-axis direction), and therefore, the size of the imaging device 100 in the vertical direction can be reduced.

[0088] like Figure 4B As shown, the motor 61 according to the present embodiment is arranged close to the process cartridge 10 installed in the apparatus main body 101. Figure 4AAs shown, a retracted shape 45 matching the contour of the motor 61 is provided in the process box 10. When the process box 10 is installed in the device body 101, the retracted shape 45 can receive a part of the motor 61. The retracted shape 45 is a shape in which the end surface of the process box 10 located at the first position in the installation direction D2 in the width direction (Y-axis direction) is retracted more toward the center side (-Y side) of the process box 10 than the end surface at the second position located upstream of the first position in the installation direction D2. According to the present embodiment, the end surface 45a of the portion of the cleaning frame 42 that protrudes more than the side cover 10a in the installation direction D2 is positioned closer to the center of the process box 10 (closer to the -Y side) than the end surface of the side cover 10a, and thus the retracted shape 45 is formed. The above-mentioned second position is, for example, a position where the length of the process box 10 in the width direction (Y-axis direction) is the largest. The first position is a position downstream of the second position in the mounting direction D2 and is a position in a region where the process cartridge 10 overlaps the motor 61 when viewed in the width direction (Y-axis direction) when the process cartridge 10 is mounted on the apparatus body 101 .

[0089] By providing the retracted shape 45 , even when the gap between the process cartridge 10 and the motor 61 is reduced, contact between the two can be avoided, which reduces the size of the image forming apparatus 100 .

[0090] It is desirable that when the process cartridge 10 is installed in the apparatus main body 101, the motor 61 overlaps a portion of the process cartridge 10 when viewed in the width direction (Y-axis direction), and overlaps the other portion of the process cartridge 10 when viewed in the installation direction D2. According to the present embodiment, when viewed in the width direction (Y-axis direction) with the process cartridge 10 installed in the apparatus main body 101, the motor 61 overlaps the cleaning frame 42 of the process cartridge 10. According to the present embodiment, when the process cartridge 10 is installed in the apparatus main body 101, the motor 61 overlaps the side cover 10a of the process cartridge 10 when viewed in the installation direction D2. Such an arrangement of the motor 61 and the process cartridge 10 overlapping each other enables the size of the imaging apparatus 100 to be further reduced.

[0091] In addition, if Figure 6 As shown, the motor 61 is arranged so as not to overlap with the developing frame 46 of the process cartridge 10 when viewed in the width direction (Y-axis direction). Therefore, in the configuration in which the motor 61 is located near the process cartridge 10, it is possible to prevent the width of the developing frame 46 from being reduced to avoid the motor 61, and therefore, the volume of the space for storing toner (toner storage portion) in the developing frame 46 is reduced. That is, the size of the image forming apparatus 100 can be reduced while ensuring the image quality and the toner capacity of the process cartridge 10 (which has an influence on the number of sheets that can be printed using the process cartridge 10).

[0092] Reference below Figure 6 and Figure 7 The positional relationship between the motor 61 and the side wall 30 a of the housing 102 will be described. Figure 6 is a cross-sectional view of the imaging apparatus 100 cut through an XZ plane. Figure 7 is a cross-sectional view of the imaging apparatus 100 cut through the YZ plane.

[0093] The motor 61 is arranged so as to overlap with the side wall 30 a of the housing 102 when viewed in the width direction (Y-axis direction). Figure 6 ). That is, the motor 61 is arranged inside the housing 102 so as to overlap with the side wall 30a when viewed in the width direction. This arrangement allows the motor 61 to be arranged using the space behind the side wall 30a in the housing 102, thereby reducing the size of the imaging device 100.

[0094] That is, the present embodiment can provide an imaging device that can be further reduced in size.

[0095] As described above, the motor 61 is arranged on the inner side ( Figure 7 ). More specifically, the motor 61 is arranged between the side wall 30a and the side plate 54 in the width direction (Y-axis direction). This configuration allows the motor 61 to be arranged using the space between the side wall 30a and the side plate 54, thereby reducing the size of the imaging device 100. According to the present embodiment, at least a portion of the upper edge portion of the side plate 54 extends upward beyond the discharge tray 30 when viewed in the width direction (Y-axis direction). A portion of the motor 61 is located between the side wall 30a and the portion of the side plate 54 that extends upward beyond the discharge tray 30.

[0096] The motor 61 is arranged above the sheet tray 21 (storage portion) so as to overlap with the sheet tray 21 (storage portion) when viewed in the vertical direction (Z-axis direction). This configuration allows the image forming apparatus 100 to be further reduced in size compared to when the motor 61 is arranged while avoiding the sheet tray 21 (storage portion) in the X-axis or Y-axis direction, for example.

[0097] Reference below Figure 8 A method for mounting the motor 61 on the side plate 54 according to the present embodiment is described. The motor 61 is fixed to the side plate 54 using one or more fasteners (screws 62). Each screw 62 passes through a hole provided in the side plate 54 from the outside to the inside in the width direction (Y-axis direction) and is screwed into a screw hole provided in the mounting base 611.

[0098] The side plate 54 has a through hole 54a that allows the pinion 61a (output gear) of the motor 61 to pass therethrough. When the motor 61 is mounted on the side plate 54, the motor body 610 is located inside the side plate 54, and the pinion 61a is located outside the side plate 54.

[0099] Fig. 9 The drive transmission mechanism DT of the imaging device 100 according to the present embodiment is shown. The drive transmission mechanism DT transmits the driving force of the motor 61, which is a driving source, to a driven object included in the imaging device 100. The drive transmission mechanism DT according to the present embodiment mainly includes a gear train composed of a plurality of gears meshing with each other.

[0100] The drive transmission mechanism DT according to the present embodiment includes a first gear train 66 serving as a drive transmission unit (first drive transmission unit) that transmits the driving force received from the motor 61 to the photosensitive drum 1 and the pressure roller 27 .

[0101] The drive transmission mechanism DT also includes a second gear train 68 serving as a second drive transmission unit that transmits the driving force of the motor 61 received via the first gear train 66 to the feeding unit 22 and other units.

[0102] The first gear train 66 includes a gear meshing with the pinion gear 61 a , a coupling gear 64 that outputs a driving force toward the process cartridge 10 , and a pressure roller gear 65 that outputs a driving force toward the fixing device 26 .

[0103] The coupling gear 64 includes an output coupling 64 a which is coupled to an input coupling 1 a ( Figure 4A ) is engaged. The output coupling 64a is connected to the side plate 54 through the through hole 54b ( Figure 8 ) protrudes inwardly from the side plate 54. The output coupling 64a rotates together with the photosensitive drum 1 about the rotation axis of the photosensitive drum 1. When the process cartridge 10 is mounted, the coupling gear 64 rotates together with the photosensitive drum 1.

[0104] The pressure roller gear 65 meshes with an input gear provided at, for example, the end of the roller shaft of the pressure roller 27. The input gear is connected to the pressure roller 27 through a through hole 54c ( Figure 8 ) protrudes outward from the side plate 54 and is arranged to mesh with the pressure roller gear 65 located on the outer side of the side plate 54.

[0105] By providing the through holes 54b and 54c as described above, it is possible to transmit drive from the first gear train 66 located on the outside of the side plate 54 to the photosensitive drum 1 and the pressure roller 27 located on the inside of the side plate 54. It is desirable that the through hole 54a through which the pinion 61a is allowed to be inserted is arranged in the X-axis direction between the through holes 54b and 54c corresponding to the photosensitive drum 1 and the pressure roller 27, respectively. As described below, this configuration reduces fluctuations in the rotation speeds of the photosensitive drum 1 and the pressure roller 27, and reduces degradation in image quality.

[0106] like Figure 7 and Fig. 9 As shown, the first gear train 66 is arranged in a space outside the side plate 54 and inside the right cover 102R in the width direction (Y-axis direction), and the right cover is a right side (+Y side) exterior member of the housing 102. The drive transmission mechanism DT is arranged in a space outside the side plate 54 and inside the right cover 102R in the width direction (Y-axis direction), and the right cover is a right side (+Y side) exterior member of the housing 102. By accommodating the first gear train 66 or the drive transmission mechanism DT in such a space, the size of the imaging device can be further reduced.

[0107] According to the present embodiment, the sheet conveying path is formed so that the sheet S is conveyed in a substantially horizontal direction (X-axis direction) between the transfer portion Nt and the fixing portion Nf. That is, the image forming apparatus 200 has a so-called S-shaped path layout. According to the S-shaped path layout, when viewed in the width direction (Y-axis direction), the sheet S is conveyed toward one side (+X side) in the horizontal direction, and thereafter, an image is formed while the sheet S is being conveyed toward the other side (-X side) in the horizontal direction, and the sheet S is discharged toward the one side (+X side) in the horizontal direction.

[0108] In the horizontal direction (X-axis direction) along the sheet conveying direction from the transfer portion Nt to the fixing portion Nf, the center axis A61 of the motor 61 is located between the rotation axis A1 of the photosensitive drum 1 and the rotation axis A2 of the pressure roller 27. This arrangement allows a reduction in the distance between the motor 61 serving as a driving source and each of the photosensitive drum 1 and the pressure roller 27 serving as driven members.

[0109] The smaller value of the above distance can reduce the fluctuation of the rotation speed of the photosensitive drum 1 or the pressure roller 27 that occurs in the drive transmission unit (first gear train 66) that transmits the driving force from the motor 61 to the photosensitive drum 1 and the pressure roller 27. That is, the fluctuation of the rotation speed that occurs in the meshing portion of the gears is reduced as the number of gears constituting the first gear train 66 is reduced, and therefore, the fluctuation of the rotation speed of the photosensitive drum 1 or the pressure roller 27 (which are driven members) can be reduced. Therefore, the deterioration of image quality (uneven density and magnification variation in the sub-scanning direction) caused by the fluctuation of the rotation speed of the photosensitive drum 1 or the pressure roller 27 can be reduced.

[0110] The drive transmission unit is not limited to the gear train. For example, the drive transmission unit may include a belt transmission mechanism that transmits the driving force using a belt. Even in this case, if the distance between the motor 61 and each of the photosensitive drum 1 and the pressure roller 27 is small, the fluctuation of the rotation speed of the photosensitive drum 1 or the pressure roller 27 due to, for example, expansion and contraction of the belt can be reduced, and the same advantages as the first embodiment can be obtained.

[0111] Second embodiment

[0112] The imaging device according to the second embodiment is described below. Unlike the first embodiment, according to this embodiment, a driving unit obtained by pre-assembling a motor and a gear train into a unit is mounted on a side plate. Hereinafter, unless otherwise specified, elements marked with the same reference numerals as those of the first embodiment have substantially the same configuration and operation as those of the first embodiment, and mainly the differences from the first embodiment are described.

[0113] Fig. 10A and Fig. 10B A method for mounting the motor 61 and the first gear train 66 according to the present embodiment is shown. Fig. 10A The drive unit 60 is shown removed from the side plate 54 . Fig. 10B The drive unit 60 is shown mounted on the side plate 54 .

[0114] like Fig. 10A As shown, the drive unit 60 includes a motor 61, a gear train 67, and a support member 69 that supports the motor 61 and the gear train 67. The constituent elements of the gear train 67 correspond to the constituent elements of the first gear train 66 according to the first embodiment. The support member 69 includes two metal plates that sandwich the gear train 67 from one side and the other side in the width direction (Y-axis direction). The motor 61 is mounted on the support member 69 so that the pinion 61a ( Figure 8 ) faces outward in the width direction (Y-axis direction). The drive unit 60 is assembled in advance so that the motor 61 is mounted on the support member 69 and the gear train 67 is held by the support member 69.

[0115] like Fig. 10A and Fig. 10B As shown, the drive unit 60 is mounted on the side plate 54 from the outside to the inside in the width direction (Y-axis direction) (arrow A), and is fixed to the side plate 54 with screws or the like. The drive unit 60 is installed so that the motor body 610 and the output coupling 64a protrude into the inside of the side plate 54 through the opening 54d and the through hole 54b of the side plate 54.

[0116] When the drive unit 60 is mounted on the side plate 54, the positional relationship among the motor 61, the side wall 30a, the laser scanner 11, the sheet tray 21, the process cartridge 10, etc. is the same as that according to the first embodiment. For example, the motor 61 is arranged to overlap with the side wall 30a of the housing 102 when viewed in the width direction (Y-axis direction) ( Figure 6 ).

[0117] Even this configuration can provide the same advantages as those according to the first embodiment. That is, the present embodiment can provide an imaging device whose size can be further reduced. In addition, according to the present embodiment, since the motor 61 and the gear train 67 are pre-assembled into a unit, the operability of assembly can be improved.

[0118] The drive unit 60 may include gears equivalent to some or all of the gears of the second gear train 68 of the first embodiment in addition to the gear train 67 corresponding to the first gear train 66 of the first embodiment. The drive unit 60 may include gears for transmitting the driving force to the discharge roller pair 29 and an actuator other than the motor 61.

[0119] Third embodiment

[0120] The following describes an image forming apparatus according to a third embodiment. According to this embodiment, the layout of the sheet conveying path inside the image forming apparatus is different from the layout according to the first embodiment. Hereinafter, unless otherwise specified, the elements marked with the same reference numerals as those of the first embodiment have substantially the same construction and operation as those of the first embodiment, and mainly the differences from the first embodiment are described.

[0121] Fig.11 2 is a schematic diagram of an XZ cross section of an image forming apparatus 200 according to the third embodiment. The image forming apparatus 100 includes an apparatus main body 101, a process cartridge including a photosensitive drum 1 (not shown), and a sheet tray 21. The apparatus main body 101 includes a housing 102, a feed unit 22 held in the housing 102, a laser scanner 11, a conveying roller pair 24, a transfer roller 25, a fixing device 26, a discharge roller pair 29, and a motor 61. A discharge tray 30 and a side wall 30a are provided in a top surface portion of the housing 102.

[0122] According to the present embodiment, the sheet conveying path is formed so that the sheet S is conveyed from the transfer portion Nt to the fixing portion Nf in a substantially vertical direction (Z-axis direction). That is, the image forming apparatus 200 has a so-called C-shaped path layout. According to the C-shaped path layout, when viewed in the width direction (Y-axis direction), the sheet S is conveyed toward one side (-X side) in the horizontal direction, and thereafter, an image is formed while the sheet S is being conveyed upward, and the sheet S is discharged toward the other side (+X side) in the horizontal direction. In addition, when viewed in the vertical direction (Z-axis direction), the discharge tray 30 and the sheet tray 21 overlap each other.

[0123] The motor 61 drives the photosensitive drum 1 and the pressure roller 27. According to the present embodiment, the motor 61 is also arranged to overlap with the side wall 30a of the housing 102 when viewed in the width direction (Y-axis direction). Figure 6 ). As in the first embodiment, the motor 61 is arranged outside the side wall 30a and inside the side plate of the housing 102. A drive transmission unit (corresponding to the first gear train 66 according to the first embodiment) that transmits the driving force from the motor 61 to the photosensitive drum 1 and the pressure roller 27 is arranged outside the side plate 54.

[0124] Therefore, with the arrangement according to the present embodiment, the same advantages as those in the first embodiment can be obtained. That is, the present embodiment can provide an imaging device that can be reduced in size.

[0125] According to the present embodiment, in the vertical direction (Z-axis direction) along the sheet conveying direction from the transfer portion Nt to the fixing portion Nf, the center axis A61 of the motor 61 is located between the rotation axis A1 of the photosensitive drum 1 and the rotation axis A2 of the pressure roller 27. This arrangement allows a reduction in the distance between the motor 61 (which is a driving source) and each of the photosensitive drum 1 and the pressure roller 27 (which is a driven member). This configuration can reduce the degradation of image quality (uneven density and magnification variation in the sub-scanning direction) caused by fluctuations in the rotation speed of the photosensitive drum 1 or the pressure roller 27.

[0126] Other embodiments

[0127] Although the above embodiment has been described with reference to an image forming apparatus including only one process cartridge 10 as an example, the technology of the present disclosure is not limited thereto. The image forming apparatus may include a plurality of cartridges, each of which is removable from the apparatus main body 101. The plurality of cartridges are not limited to process cartridges, but may also be developing cartridges corresponding to the developing unit 40 or toner cartridges containing a developer (toner) to be supplied.

[0128] The configuration of the process cartridge 10 is not limited to that according to the first embodiment. The process cartridge 10 may include the photosensitive drum 1 and any one of a charging unit, a developing unit, and a cleaning unit that operate for the photosensitive drum 1.

[0129] Instead of including the process cartridge 10 which can be removed from the apparatus main body 101 by the user, the image forming apparatus may include an image forming unit which is built into the apparatus main body 101 so that the user cannot remove it by himself.

[0130] The imaging device may include a plurality of imaging units to form a color image using toners of a plurality of colors. The imaging device may include a plurality of motors, each motor corresponding to one of the plurality of imaging units. In this case, it is desirable that at least one of the motors is arranged to overlap with the side wall 30a when viewed in the width direction (Y-axis direction).

[0131] The image forming apparatus is not limited to a single-function printer having only an image forming function (printing function), but may be a copier, a fax machine, or a multifunction printer.

[0132] According to the present disclosure, it is possible to provide an imaging device that can be further reduced in size.

[0133] While the present disclosure has been described with reference to exemplary embodiments, it is to be understood that the present disclosure 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 modifications and equivalent structures and functions.

Claims

1. An imaging device, comprising: a housing configured to accommodate an image forming unit that forms an image on a recording material; a discharge unit including a roller and configured to discharge the recording material to the outside of the housing; as well as a motor arranged inside the housing and configured to drive the imaging unit, Wherein, the housing comprises: a stacking unit on which the recording material discharged by the discharge unit is stacked, and a wall surface, the wall surface being arranged at an end of the stacking unit in a width direction, the width direction being perpendicular to both the vertical direction and the discharge direction of the discharge unit, and the wall surface extending upward beyond the stacking unit, and The motor is arranged at a position overlapping with the wall surface when viewed along the width direction.

2. The imaging device according to claim 1, wherein The housing includes a first side plate intersecting with the width direction, The motor is supported by the first side plate and is arranged on an inner side of the first side plate in the width direction.

3. The imaging device according to claim 2, further comprising: a drive transmission unit configured to transmit a driving force from the motor to the imaging unit, Wherein, the drive transmission unit is arranged on the outer side of the first side plate in the width direction.

4. The imaging device according to claim 2, wherein: The imaging unit is configured to be removable from the housing, Wherein, the housing includes a second side plate intersecting with the width direction, and Wherein, in the width direction, a space for installing the imaging unit is formed between the first side plate and the second side plate.

5. The imaging device according to claim 4, wherein: When the imaging unit is mounted in the housing, the motor overlaps the imaging unit when viewed in the width direction, and overlaps the imaging unit when viewed in a mounting direction in which the imaging unit is mounted to the housing.

6. The imaging device according to claim 5, wherein: The image forming unit includes a developing frame configured to store a developer, and Wherein, when the imaging unit is mounted in the housing, the motor does not overlap with the developing frame when viewed along the width direction.

7. The imaging device according to claim 5, wherein: The imaging unit has a shape in which an end surface of the imaging unit in the width direction at a first position in the installation direction is retreated more toward the center side of the imaging unit in the width direction than an end surface of the imaging unit at a second position upstream of the first position in the installation direction.

8. The imaging device according to claim 4, further comprising: an exposure device configured to emit light onto a photosensitive drum of the imaging unit for exposure, wherein the housing includes a first frame and a second frame, the first frame and the second frame are respectively connected to the first side plate and the second side plate to support the exposure device, and the first frame and the second frame are arranged separately from each other in the installation direction of the imaging unit, and Wherein, the motor is arranged between the first frame and the second frame in the installation direction.

9. The imaging device according to claim 8, wherein: When viewed along the mounting direction, the motor overlaps with at least one of the first frame or the second frame.

10. The imaging device according to claim 8, wherein A protruding portion is provided on a bottom surface portion of the exposure device so as to protrude downward beyond a top surface of the first frame and a top surface of the second frame through a space between the first frame and the second frame, and The concave portion is provided on a top surface portion of the imaging unit to be recessed downward and face the protruding portion.

11. The imaging device according to claim 1, further comprising: an exposure device configured to emit light onto a photosensitive drum of the imaging unit for exposure, The housing includes a first side plate intersecting the width direction, a second side plate intersecting the width direction and facing the first side plate in the width direction, and a first frame and a second frame connected to the first side plate and the second side plate, respectively. wherein the first frame and the second frame support the exposure device and are arranged apart from each other in a horizontal direction intersecting both the vertical direction and the width direction, and Wherein, the motor is arranged between the first frame and the second frame in the horizontal direction.

12. The imaging device according to claim 1, further comprising: a storage portion configured to store a recording material, Wherein, the motor is arranged at a position overlapping with the storage portion when viewed in the vertical direction.

13. The imaging device according to claim 1, further comprising: a transfer member configured to form, together with a photosensitive drum of the image forming unit, a transfer portion in which a toner image is transferred from the photosensitive drum to the recording material; as well as a fixing device including a heating member, a heating unit configured to heat the heating member, and a pressing member forming a fixing portion together with the heating member, wherein the fixing device heats the toner image by using the heating member while the recording material is conveyed in the fixing portion, and The motor rotationally drives the photosensitive drum and one of the heating member or the pressing member.

14. The imaging device according to claim 13, wherein In a horizontal direction along a conveying direction of the recording material from the transfer section to the fixing section, A central axis of the motor is located between a rotation axis of the photosensitive drum and a rotation axis of the one of the heating member or the pressing member.

Images