Image forming device

Abstract

To efficiently cool a heating unit so that a mechanism for moving the heating unit to a position away from a fixing unit does not get in the way. [Solution] A unit moving mechanism (7) moves a heating unit (5a) in conjunction with movement of an operating member (103). A pair of fans (6) are spaced apart in a first direction and blow air toward the heating unit (5a). The heating unit (5a) includes a ventilation duct (54) having a cavity (540a) formed along the first direction, a pair of inlet openings (540b) formed opposite the pair of fans (6), and an outlet opening (540c) formed between the pair of inlet openings (540b) in the first direction. The unit moving mechanism (7) includes a unit connecting member (56) and a link mechanism (7x). The unit connecting member (56) is connected to the heating unit (5a) with a gap (5600) between it and the outlet opening (540c).

Description

[Technical Field]

[0001] The present invention relates to an electrophotographic image forming apparatus equipped with a heating unit and a fixing unit. [Background technology]

[0002] An electrophotographic image forming apparatus transfers a toner image from an image carrier to a sheet, and fixes the toner image onto the sheet by a fixing device.

[0003] The fixing device may be divided into a heating unit having a heater and a fixing unit having a fixing member and a pressure roller. The heater heats the fixing member.

[0004] Furthermore, it is known that the image forming apparatus includes a mechanism that moves the heating unit from the heating position to the retracted position in conjunction with operation on the control unit (see, for example, Patent Document 1). When the heating unit is retracted to the retracted position, the fixing unit can be pulled out from the main body. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-86093 Summary of the Invention [Problem to be solved by the invention]

[0006] Incidentally, it is important that the heating unit is cooled efficiently in order to avoid adverse effects of heat on peripheral devices of the fixing device in the image forming apparatus.

[0007] On the other hand, in order to make it possible to pull out the fixing unit from the main body, the image forming apparatus needs to be provided with a unit moving mechanism that moves the heating unit to a position away from the fixing unit.

[0008] The unit movement mechanism is positioned on the opposite side of the heating unit from the fixing unit. It is desirable to efficiently cool the heating unit so that the unit movement mechanism does not interfere with it.

[0009] The object of the present invention is to provide an image forming apparatus that can efficiently cool the heating unit so that the mechanism for moving the heating unit to a position away from the fixing unit does not interfere with the cooling. [Means for solving the problem]

[0010] An image forming apparatus according to one aspect of the present invention comprises a main body, a fixing unit, a heating unit, an operating member, a unit moving mechanism, and a pair of fans. The main body has an exposed opening that exposes its interior to the outside. The fixing unit is arranged in the main body along a first direction inside the exposed opening and has a fixing member that is heated and a pressurizing member that biases a sheet onto the fixing member. The heating unit is arranged in the main body along the first direction, aligned with the fixing unit in a second direction perpendicular to the first direction, and has a heater that heats the fixing member. The operating member is a member that can be moved by operation. The unit moving mechanism is arranged in the main body on the side of the heating unit in the second direction that is opposite to the fixing unit, and moves the heating unit between a reference position along the fixing unit and a retracted position further away from the fixing unit than the reference position in conjunction with the movement of the operating member. The pair of fans are positioned within the main body at a distance in the first direction from the heating unit in the second direction relative to the unit movement mechanism, and blow air toward the heating unit. When the heating unit is in the retracted position, the fixing unit can be pulled out from within the main body along the first direction. The heating unit includes a ventilation duct having a cavity formed along the first direction, a pair of inlet openings formed opposite the pair of fans and communicating with the cavity, and an outlet opening formed between the pair of inlet openings in the first direction and communicating with the cavity. The unit movement mechanism includes a unit connecting member and a link mechanism. The unit connecting member is connected to the heating unit with a gap between it and the outlet opening at a position between the pair of inlet openings in the first direction. The link mechanism transmits the movement of the operating member to the unit connecting member. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an image forming apparatus that can efficiently cool the heating unit so that the mechanism for moving the heating unit to a position away from the fixing unit does not interfere with it. [Brief explanation of the drawings]

[0012] [Figure 1] Figure 1 is a configuration diagram of an image forming apparatus according to an embodiment. [Figure 2] Figure 2 shows a partial configuration of the fixing device in the image forming apparatus according to the embodiment. [Figure 3] Figure 3 is a perspective view of the main frame of the image forming apparatus according to this embodiment. [Figure 4] Figure 4 is a front view of the fixing device in the proximity state in the image forming apparatus according to the embodiment. [Figure 5] Figure 5 is a front view of the fixing device in the separated state in the image forming apparatus according to the embodiment. [Figure 6] Figure 6 is a perspective view of the fixing unit in the image forming apparatus according to this embodiment. [Figure 7] Figure 7 is a plan view of the fixing device and the unit movement mechanism in a biased state in an image forming apparatus according to an embodiment. [Figure 8] Figure 8 is a plan view of the fixing device and the unit movement mechanism in the pulled state in the image forming apparatus according to the embodiment. [Figure 9] Figure 9 is a perspective view in which some of the movable members in the image forming apparatus according to the embodiment have been omitted. [Figure 10] Figure 10 is a plan view of the connecting mechanism of the connecting member when the unit moving mechanism in the image forming apparatus according to the embodiment is in a biased state. [Figure 11] Figure 11 is a plan view of the unit connecting mechanism of the image forming apparatus according to the embodiment when the unit moving mechanism is in the pulled-back state. [Figure 12] Figure 12 is a perspective view of a part of the first link member and a part of the regulating frame member in an image forming apparatus according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following embodiment is an example of the present invention, and does not limit the technical scope of the present invention.

[0014] [Configuration of image forming apparatus 10] The image forming apparatus 10 according to this embodiment performs printing using an electrophotographic method. The printing process is the process of forming an image on a sheet 900.

[0015] 1, the image forming apparatus 10 includes a sheet storage unit 2, a sheet conveying device 3, and a printing device 4. The sheet conveying device 3 and the printing device 4 are housed in a main body 1, which is a housing. The main body 1 includes a main body frame 1x that forms the framework of the main body 1, and an exterior member attached to the main body frame 1x.

[0016] The sheet storage section 2 is capable of accommodating multiple sheets 900. The sheet conveying device 3 includes a sheet feeding device 30 and multiple pairs of conveying rollers 31.

[0017] The sheet feeding device 30 sends the sheets 900 from the sheet storage section 2 one by one to the transport path 300. The transport path 300 is the passage for the sheets 900.

[0018] The plurality of pairs of transport rollers 31 transport the sheet 900 along the transport path 300. One of the plurality of pairs of transport rollers 31 discharges the sheet 900, on which an image has been formed, from the transport path 300 onto the discharge tray 1a.

[0019] The printing device 4 performs the printing process on the sheet 900 conveyed along the conveying path 300. The image formed on the sheet 900 is a toner image.

[0020] The printing device 4 includes an optical scanning unit 40, one or more image forming units 4x, a transfer device 45, and a fixing device 5. The image forming unit 4x includes a photoconductor 41, a charging device 42, a developing device 43, and a drum cleaning device 44.

[0021] The charging device 42 charges the surface of the photoconductor 41. The optical scanning unit 40 scans a light beam over the charged surface of the photoconductor 41. As a result, the optical scanning unit 40 forms an electrostatic latent image on the surface of the photoconductor 41.

[0022] The developing device 43 develops the electrostatic latent image into a toner image by supplying toner to the surface of the photoreceptor 41. The transfer device 45 transfers the toner image formed on the surface of the photoreceptor 41 to a sheet 900.

[0023] The transfer device 45 transfers the electrostatic latent image onto the sheet 900 at a transfer position P1 on the transport path 300.

[0024] In this embodiment, the printing device 4 is a tandem color printing device having a plurality of image forming units 4x. The transfer device 45 also has an intermediate transfer belt 450, a plurality of primary transfer devices 451, a secondary transfer device 452, and a belt cleaning device 453.

[0025] 1, the printing device 4 includes four image forming units 4x corresponding to the four colors of toner: yellow, magenta, cyan, and black. The transfer device 45 includes four primary transfer devices 451 corresponding to the four image forming units 4x.

[0026] The intermediate transfer belt 450 is rotatably supported by a plurality of support rollers 454. One of the plurality of support rollers 454 is rotated by being driven by a belt driving device (not shown), thereby rotating the intermediate transfer belt 450.

[0027] Each primary transfer device 451 transfers the toner image formed on the surface of the photoconductor 41 in each image forming unit 4x onto the surface of the intermediate transfer belt 450. As a result, a composite toner image, in which the four color toner images are combined, is formed on the surface of the intermediate transfer belt 450.

[0028] The intermediate transfer belt 450 rotates while carrying the synthesized toner image. The secondary transfer device 452 transfers the synthesized toner image formed on the surface of the intermediate transfer belt 450 to the sheet 900 at the transfer position P1.

[0029] The drum cleaning device 44 removes primary waste toner from the surface of the photoreceptor 41. The primary waste toner is the toner remaining on the surface of the photoreceptor 41 that has passed through the primary transfer device 451.

[0030] The belt cleaning device 453 removes secondary waste toner from the surface of the intermediate transfer belt 450. The secondary waste toner is the toner remaining on the surface of the intermediate transfer belt 450 that has passed through the secondary transfer device 452.

[0031] The fixing device 5 heats and pressurizes the synthesized toner image on the sheet 900 at the fixing position P2 in the transport path 300. This causes the fixing device 5 to fix the synthesized toner image to the sheet 900. The fixing position P2 is located downstream of the transfer position P1 in the sheet transport direction.

[0032] As shown in FIG. 2, the fixing device 5 includes a heater 51, a fixing belt 52, a fixing roller 520, a pressure roller 53, and a sheet separating member 5200.

[0033] The fixing belt 52 is a flexible cylindrical member that encloses a fixing roller 520. The fixing belt 52 is heated by a heater 51.

[0034] The fixing roller 520 is a cylindrical member that supports the fixing belt 52 from its inside. The fixing roller 520 is rotatably supported. The fixing belt 52 is rotatable together with the fixing roller 520.

[0035] The fixing belt 52 has a conductive substrate, an elastic layer formed on the outer periphery of the substrate, and a release layer formed on the outer periphery of the elastic layer.

[0036] The heater 51 is positioned opposite the outer circumferential surface of the fixing belt 52 and heats the fixing belt 52. In this embodiment, the heater 51 is an electromagnetic induction heating device. The heater 51 mainly heats the base material of the fixing belt 52 by electromagnetic induction. For example, a halogen heater may be used as the heater 51.

[0037] The pressure roller 53 is rotatably supported. The pressure roller 53 is driven and rotated by a drive device (not shown). The fixing belt 52 and fixing roller 520 rotate in conjunction with the pressure roller 53.

[0038] The fixing belt 52 heats the toner image formed on the sheet 900. The pressure roller 53 pressurizes the sheet 900 toward the sheet 900 by biasing the sheet 900 toward the fixing belt 52.

[0039] The fixing belt 52 is an example of a fixing member that is heated by the heater 51. The pressure roller 53 is an example of a pressure member that biases the sheet 900 onto the fixing belt 52.

[0040] The sheet separation member 5200 separates the sheet 900 from the fixing belt 52 when the sheet 900 adheres to the fixing belt 52.

[0041] In this embodiment, the fixing device 5 is divided into a heating unit 5a and a fixing unit 5b (see Figures 4 and 5). The heating unit 5a is arranged within the main body 1 along the first direction D1. The fixing unit 5b is also arranged within the main body 1 along the first direction D1.

[0042] In other words, the heating unit 5a and the fixing unit 5b are arranged such that their respective longitudinal directions are aligned with the first direction D1.

[0043] The heating unit 5a and the fixing unit 5b are arranged side by side in the second direction D2. That is, the second direction D2 is the direction in which the heating units 5a and the fixing units 5b are arranged. The second direction D2 is a direction perpendicular to the first direction D1.

[0044] In the following description, one side of the second direction D2 is referred to as a first side D21, and the other side of the second direction D2 is referred to as a second side D22 (see FIGS. 3 to 5 and 7 to 12). The heating unit 5a is disposed on the first side D21 with respect to the fixing unit 5b (see FIGS. 4, 5, 7, and 8).

[0045] The heating unit 5a includes a heater 51 and a first support 54. The fixing unit 5b includes a fixing belt 52, a fixing roller 520, a pressure roller 53, and a second support 55.

[0046] First support 54 is a member that supports heater 51. Second support 55 is a member that supports fixing belt 52, fixing roller 520, and pressure roller 53. Fixing belt 52 is supported by second support 55 via fixing roller 520.

[0047] The main body frame 1x is made up of a combination of multiple metal pipes (see FIG. 3). The heating unit 5a and the fixing unit 5b are supported by the main body frame 1x. The fixing unit 5b is disposed on the first side D21 of the heating unit 5a in the second direction D2.

[0048] The multiple metal pipes that make up the main frame 1x include a restricting section 11 and a lower support section 12 (see Figures 3-5).

[0049] In this embodiment, the restricting portion 11 is two support pipes that are formed to extend in the vertical direction D3 and are spaced apart in the first direction D1 (see FIG. 3). The vertical direction D3 is the up-down direction.

[0050] The lower support portion 12 is formed below the heating unit 5a and the fixing unit 5b, extending in the second direction D2, and is made up of two beam pipes spaced apart in the first direction D1 (see FIG. 3).

[0051] The heating unit 5a and the fixing unit 5b are placed on the lower support portion 12 with their longitudinal directions aligned with the first direction D1 (see FIGS. 7 and 8). That is, the lower support portion 12 supports the heating unit 5a and the fixing unit 5b from below.

[0052] The heating unit 5a is movable in the second direction D2 on the lower support portion 12. Specifically, the heating unit 5a is movable between a reference position along the fixing unit 5b and a retracted position that is farther away from the fixing unit 5b toward the first side D21 than the reference position. The fixing unit 5b is disposed between the heating unit 5a and the restriction portion 11 (see FIGS. 4 and 5).

[0053] When the heating unit 5a is in the retracted position, the fixing unit 5b can be pulled out from inside the main body 1 along the first direction D1 (see FIGS. 5 and 8).

[0054] The main body 1 has an exposure opening 101 that exposes the interior to the outside (see FIGS. 7 and 8). The fixing unit 5b is arranged inside the exposure opening 101 in the main body 1 along the first direction D1. The heating unit 5a is arranged in the main body 1 along the first direction D1, aligned with the fixing unit 5b in the second direction D2 (see FIGS. 7 and 8).

[0055] The exposure opening 101 is an opening that opens one end of the fixing unit 5b in the first direction D1 to the outside of the main body 1. The image forming apparatus 10 includes a cover member 102 that can open and close the exposure opening 101 (see FIGS. 7 and 8).

[0056] The cover member 102 is supported by the first support shaft 102x. This allows the cover member 102 to rotate around the first support shaft 102x. The cover member 102 is rotatable between a closed position that closes the exposed opening 101 and an open position that opens the exposed opening 101.

[0057] Figure 7 shows the cover member 102 and the fixing device 5 in the closed position, and Figure 8 shows the cover member 102 and the fixing device 5 in the open position.

[0058] When the cover member 102 is in the closed position, it is held in that position by a locking mechanism (not shown). When the lock by the locking mechanism is released, the cover member 102 can rotate from the closed position to the open position.

[0059] When the cover member 102 is in the open position, the fixing unit 5b can be pulled out from the main body 1 through the exposure opening 101 (see FIG. 8).

[0060] Incidentally, efficient cooling of the heating unit 5a is important in order to avoid adverse thermal effects on the surrounding equipment of the fixing device 5 in the image forming apparatus 10.

[0061] On the other hand, in order to enable the fixing unit 5b to be pulled out from the main body 1, the image forming apparatus 10 is equipped with a unit movement mechanism 7 (see Figures 7 and 8). The unit movement mechanism 7 moves the heating unit 5a between the reference position and the retracted position.

[0062] The unit movement mechanism 7 is disposed on the opposite side of the heating unit 5a from the fixing unit 5b in the second direction D2. That is, the unit movement mechanism 7 is disposed on the first side D21 in the second direction D2 from the heating unit 5a. It is desirable to efficiently cool the heating unit 5a so that the unit movement mechanism 7 does not get in the way.

[0063] The image forming apparatus 10 is configured to efficiently cool the heating unit 5a so that the unit movement mechanism 7 does not get in the way.

[0064] The image forming apparatus 10 includes a pair of fans 6 spaced apart in the first direction D1 that blow air toward the heating unit 5a (see FIGS. 7 and 8). The pair of fans 6 are located within the main body 1 on a first side D21 in the second direction D2 relative to the unit movement mechanism 7 (see FIGS. 1, 4, 5, 7, and 8). That is, the pair of fans 6 are located on the opposite side of the unit movement mechanism 7 from the heating unit 5a in the second direction D2.

[0065] [Configuration of Unit Movement Mechanism 7] The image forming apparatus 10 includes a unit moving mechanism 7 and an operating member 103 connected to the unit moving mechanism 7 (see FIGS. 7 and 8). In this embodiment, the cover member 102 also serves as the operating member 103.

[0066] The operating member 103 can be moved in a first operating direction or a second operating direction by being operated. The operating member 103 is disposed at one end of the main body 1 in the first direction D1 (see FIGS. 7 and 8).

[0067] In this embodiment, the first operation direction is the movement direction of the cover member 102 when the cover member 102 is closed, and the second operation direction is the movement direction of the cover member 102 when the cover member 102 is opened.

[0068] That is, the first operation direction is the direction in which the cover member 102 moves from the open position to the closed position, and the second operation direction is the direction in which the cover member 102 moves from the closed position to the open position.

[0069] The unit movement mechanism 7 moves the heating unit 5a along the second direction D2 in conjunction with the movement of the operating member 103.

[0070] The unit moving mechanism 7 moves the heating unit 5a from the retracted position to the reference position in conjunction with the movement of the operating member 103 in the first operating direction (see FIG. 7). On the other hand, the unit moving mechanism 7 moves the heating unit 5a from the reference position to the retracted position in conjunction with the movement of the operating member 103 in the second operating direction (see FIG. 8).

[0071] The unit moving mechanism 7 includes a unit connecting member 56 and a link mechanism 7x. The unit connecting member 56 is connected to the heating unit 5a. The link mechanism 7x transmits the movement of the operating member 103 to the unit connecting member 56.

[0072] The heating unit 5a further includes a duct forming member 541 attached to the surface of the first side D21 of the first support 54 (see FIGS. 7 and 8). The heating unit 5a includes a ventilation duct 540 formed by the duct forming member 541 and the first support 54 (see FIGS. 7 and 8).

[0073] The ventilation duct 540 has a cavity 540a formed between the first support 54 and the duct forming member 541, a pair of inlet openings 540b communicating with the cavity 540a, and an outlet opening 540c communicating with the cavity 540a (see FIG. 7). The pair of inlet openings 540b and the outlet opening 540c are openings formed in the duct forming member 541.

[0074] The cavity 540a is formed along the first direction D1 (see FIG. 7). That is, the cavity 540a is formed along the heater 51 with the first direction D1 as the longitudinal direction.

[0075] The pair of inflow openings 540b are formed to face the pair of fans 6. That is, the pair of fans 6 and the pair of inflow openings 540b are respectively arranged on both outer sides of the unit connecting member 56 in the first direction D1.

[0076] The pair of fans 6 blow air toward the second side D22 in the second direction D2. The pair of inlet openings 540b open to the first side D21 in the second direction D2 at positions corresponding to the pair of fans 6 in the first direction D1.

[0077] The discharge opening 540c is formed between the pair of inlet openings 540b in the first direction D1. In this embodiment, the discharge opening 540c is open to the first side D21 in the second direction D2.

[0078] The unit connecting member 56 is connected to the heating unit 5a at a position between the pair of inlet openings 540b in the first direction D1, with a gap 5600 between it and the discharge opening 540c (see FIG. 7). The discharge opening 540c opens toward the gap 5600.

[0079] In this embodiment, the unit connecting member 56 is connected to the duct forming member 541 of the heating unit 5a by a connecting mechanism 560 (see Figures 7, 10, and 11).

[0080] The cooling air sent out by the pair of fans 6 flows into the cavity 540a through the pair of inlet openings 540b. Furthermore, the cooling air efficiently cools the heating unit 5a while flowing through the cavity 540a from both ends in the first direction D1 toward the center in the first direction D1.

[0081] Furthermore, after cooling the heating unit 5a, the cooling air flows out of the cavity 540a through the exhaust opening 540c into the gap 5600. The cooling air flows out of the gap 5600 mainly along the vertical direction D3.

[0082] Therefore, the heating unit 5a is efficiently cooled by the cooling air flowing through a path that does not obstruct the unit movement mechanism 7.

[0083] The link mechanism 7x comprises a guide member 70, a movable member 71, a first biasing member 72, and a first directional movement mechanism 73.

[0084] The first biasing member 72 biases the heating unit 5a toward the first side D21. Specifically, the first biasing member 72 is one or more elastic members that bias the heating unit 5a toward the first side D21. For example, the elastic member is a coil spring or a leaf spring.

[0085] In the example shown in FIGS. 7 and 8, the first biasing member 72 is two tension springs that elastically bias the heating unit 5a toward the first side D21.

[0086] The unit connecting member 56 has an inclined surface 7a. The inclined surface 7a is provided on the heating unit 5a facing the first side D21. The inclined surface 7a is a surface that is inclined from the second side D22 to the first side D21 with respect to the first direction D1. In this embodiment, the inclined surface 7a is provided at two locations spaced apart in the first direction D1 (see Figures 7 and 8).

[0087] The movable member 71 is supported so as to be movable along a first direction D1. The guide member 70 guides the movable member 71 along the first direction D1. For example, the guide member 70 is supported by the main frame 1x.

[0088] The movable member 71 has one or more rollers 71a that are rotatably supported (see FIGS. 7 to 9). The rollers 71a are provided at locations on the movable member 71 that correspond to the inclined surface 7a. In this embodiment, the rollers 71a are provided at two locations spaced apart in the first direction D1 (see FIGS. 7 to 9). The rollers 71a roll in contact with the inclined surface 7a.

[0089] The first direction movement mechanism 73 moves the movable member 71 along the first direction D1 in conjunction with the movement of the operating member 103. In this embodiment, the first direction movement mechanism 73 is a mechanism that converts the rotation of the operating member 103 into linear motion along the first direction D1.

[0090] The first direction movement mechanism 73 includes a first link member 731, a second link member 732, and a third link member 733 (see FIGS. 7 and 8).

[0091] One end of the first link member 731 is connected to the movable member 71, and the other end of the first link member 731 is connected to one end of the second link member 732 by a first connecting shaft 734. The other end of the second link member 732 is connected to one end of the third link member 733 by a second connecting shaft 735. The other end of the third link member 733 is connected to one end of the operating member 103 by a third connecting shaft 737.

[0092] The third link member 733 is rotatably supported by a second support shaft 736 .

[0093] In this embodiment, the first directional movement mechanism 73 moves the movable member 71 toward the rear along the first direction D1 when the operating member 103 moves from the open position to the closed position. Also, the first directional movement mechanism 73 moves the movable member 71 toward the front along the first direction D1 when the operating member 103 moves from the closed position to the open position.

[0094] As described above, the direction of movement from the open position to the closed position is the first operation direction, and the direction of movement from the closed position to the open position is the second operation direction.

[0095] In the following description, the end of the second side D22 of the inclined surface 7a will be referred to as the base end of the inclined surface 7a, and the end of the first side D21 of the inclined surface 7a will be referred to as the end portion of the inclined surface 7a. The base end is an example of the portion of the second side D22 of the inclined surface 7a. The end portion is an example of the portion of the first side D21 of the inclined surface 7a.

[0096] When the movable member 71 moves in conjunction with the movement of the operating member 103 in the first operating direction, the roller 71a rolls from the base end to the end end on the inclined surface 7a. By rolling from the base end to the end end on the inclined surface 7a, the roller 71a pushes the inclined surface 7a toward the second side D22. By pushing the inclined surface 7a toward the second side D22, the roller 71a moves the heating unit 5a toward the second side D22 against the biasing force of the first biasing member 72.

[0097] Neither the heating unit 5a nor the fixing unit 5b is fixed to the main body frame 1x by fasteners such as screws.

[0098] The restricting portion 11 restricts the movement range of the fixing unit 5b toward the second side D22. When the roller 71a moves the heating unit 5a toward the second side D22, the fixing unit 5b and the heating unit 5a are sandwiched between the movable member 71 and the restricting portion 11 (see FIGS. 4 and 7).

[0099] 7 shows the unit moving mechanism 7 in an urging state in which the movable member 71 urges the heating unit 5a and the fixing unit 5b toward the regulating portion 11. FIGS. 4 and 7 show the fixing device 5 in a proximity state in which the unit moving mechanism 7 holds the heating unit 5a close to the fixing unit 5b.

[0100] The fixing unit 5b and the heating unit 5a are sandwiched between the movable member 71 and the regulating portion 11, and are thereby positioned in the second direction D2.

[0101] That is, when the movable member 71 moves in conjunction with the movement of the operating member 103 in the first operating direction, the fixing unit 5b and the heating unit 5a are sandwiched between the movable member 71 and the regulating portion 11, and thereby positioned in the second direction D2.

[0102] The first support body 54 has a plurality of concave first fitting portions 54b that open to the second side D22 (see FIGS. 4 and 5). The second support body 55 has a plurality of convex second fitting portions 55c that can be fitted into the plurality of first fitting portions 54b, respectively (see FIGS. 4 and 5).

[0103] When the unit moving mechanism 7 moves the heating unit 5a to the second side D22, the first fitting portions 54b and the second fitting portions 55c fit together (see FIG. 4).

[0104] The plurality of first fitting portions 54b and the plurality of second fitting portions 55c are fitted together, thereby restricting the relative movement of the heating unit 5a and the fixing unit 5b in the vertical direction D3.

[0105] The second support 55 may be provided with a first fitting portion 54b, and the first support 54 may be provided with a second fitting portion 55c.

[0106] On the other hand, when the movable member 71 moves in conjunction with the movement of the operating member 103 in the second operating direction, the roller 71a rolls from the end to the base on the inclined surface 7a, and the first biasing member 72 moves the heating unit 5a to the first side D21.

[0107] 8 shows the unit moving mechanism 7 in a pulling state in which the first biasing member 72 is pulling the heating unit 5a toward the first side D21. Figures 5 and 8 show the fixing device 5 in a separated state in which the heating unit 5a is separated from the fixing unit 5b toward the first side D21 by the unit moving mechanism 7. The separated state is a state in which the heating unit 5a is in the retracted position.

[0108] In this embodiment, the movable member 71 further has a first contact surface 71b (see FIGS. 7 to 9). The unit connecting member 56 further has a second contact surface 7b corresponding to the first contact surface 71b and a first recess 7c corresponding to the roller 71a (see FIGS. 7 and 8).

[0109] The first contact surface 71b faces the second side D22 and is a surface that can come into contact with the second contact surface 7b of the unit connecting member 56. For example, the first contact surface 71b is formed in three or more places on the movable member 71. In the example shown in FIG. 9, the first contact surface 71b is formed in four places on the movable member 71.

[0110] The second contact surface 7b faces the first side D21 and is a surface that can come into contact with the first contact surface 71b of the movable member 71. The second contact surface 7b is formed at a position on the unit connecting member 56 that corresponds to the first contact surface 71b.

[0111] The first recess 7c faces the first side D21 and is positioned adjacent to the first direction D1 with respect to the end portion of the inclined surface 7a (see Figures 7 and 8). The first recess 7c is provided at a location in the unit connecting member 56 corresponding to the roller 71a. In this embodiment, the first recess 7c is provided at two locations in the unit connecting member 56.

[0112] The first recess 7c is capable of receiving a part of the roller 71a. Specifically, the first recess 7c is capable of receiving a part of the roller 71a, including the edge of the second side D22.

[0113] When the movable member 71 moves in conjunction with the movement of the operating member 103 in the first operating direction, the following first operation occurs. In the first operation, after the roller 71a rolls from the base end to the end end on the inclined surface 7a, a part of the roller 71a enters the first recess 7c and the first contact surface 71b comes into contact with the second contact surface 7b (see Figure 7).

[0114] As the first contact surface 71b comes into contact with the second contact surface 7b, the fixing unit 5b and the heating unit 5a are sandwiched between the movable member 71 and the restricting portion 11. This positions the fixing unit 5b and the heating unit 5a in the second direction D2.

[0115] Generally, there is some play between the roller 71a and its rotation axis. The fixing unit 5b and the heating unit 5a are positioned with high precision by positioning them so that the first contact surface 71b and the second contact surface 7b are in contact.

[0116] Furthermore, when the fixing unit 5b and the heating unit 5a are positioned by contact between the first contact surface 71b and the second contact surface 7b, no large force is applied to the roller 71a. Therefore, the durability of the roller 71a is improved.

[0117] On the other hand, when the movable member 71 moves in conjunction with the movement of the operating member 103 in the second operating direction, the following second operation occurs. In the second operation, after the roller 71a disengages from the first recess 7c and the first contact surface 71b separates from the second contact surface 7b, the roller 71a rolls from the end to the base on the inclined surface 7a (see Figure 8).

[0118] In this embodiment, the unit connecting member 56 further includes a third contact surface 7d corresponding to the first contact surface 71b, and a second recess 7e corresponding to the roller 71a (see FIGS. 7 and 8).

[0119] The third contact surface 7d faces the first side D21 and is a surface that can come into contact with the first contact surface 71b of the movable member 71. The second contact surface 7b is formed at a position on the unit connecting member 56 that corresponds to the first contact surface 71b.

[0120] The second recess 7e faces the first side D21 and is disposed adjacent to the base end of the inclined surface 7a in the first direction D1 (see FIGS. 7 and 8). The second recess 7e is provided at a position corresponding to the roller 71a in the unit connecting member 56. In this embodiment, the second recess 7e is provided at two positions in the unit connecting member 56.

[0121] The second recess 7e is capable of receiving a part of the roller 71a. Specifically, the second recess 7e is capable of receiving a part of the roller 71a, including the edge of the second side D22.

[0122] When the movable member 71 moves in conjunction with the movement of the operating member 103 in the second operating direction, the following third operation occurs. In the third operation, the roller 71a detaches from the first recess 7c and then rolls from the end to the base on the inclined surface 7a, after which a part of the roller 71a enters the second recess 7e and the first contact surface 71b comes into contact with the third contact surface 7d (see Figure 8).

[0123] Therefore, when the heating unit 5a is separated from the fixing unit 5b to the first side D21, the force of the first biasing member 72 is not applied to the roller 71a. As a result, the durability of the roller 71a is improved.

[0124] On the other hand, when the movable member 71 moves in conjunction with the movement of the operating member 103 in the first operating direction, the following fourth operation occurs. In the fourth operation, after the roller 71a disengages from the second recess 7e and the first contact surface 71b separates from the third contact surface 7d, the roller 71a rolls from the base end to the end end on the inclined surface 7a (see Figure 7).

[0125] In the image forming apparatus 10, the action of the roller 71a allows the heating unit 5a to smoothly move closer to or away from the fixing unit 5b.

[0126] In this embodiment, the movable member 71 further includes a roller 71f (see Figure 7). The roller 71f is in contact with the guide member 70. As the movable member 71 moves along the first direction D1, the roller 71f rolls on the surface of the guide member 70.

[0127] The action of the roller 71f allows the heating unit 5a to move more smoothly towards or away from the fixing unit 5b.

[0128] The coupling mechanism 560 comprises a shaft portion 561, an engaging portion 562, and a second biasing member 563 (see Figures 10 and 11).

[0129] The shaft portion 561 is formed to protrude from the heating unit 5a toward the first side D21 in the second direction D2. In this embodiment, the first end of the shaft portion 561 is fixed to the duct forming member 541.

[0130] The shaft portion 561 is inserted through a through hole 56a formed in the unit connecting member 56 along the second direction D2. The engaging portion 562 is formed at the second end of the shaft portion 561. The engaging portion 562 is larger than the inner diameter of the through hole 56a.

[0131] The engaging portion 562 engages with the edge of the through hole 56a in the unit connecting member 56 when the unit connecting member 56 moves to the first side D21 in the second direction D2, preventing the shaft portion 561 from coming out of the through hole 56a.

[0132] The second biasing member 563 is disposed between the unit connecting member 56 and the heating unit 5a. As a result, the second biasing member 563 functions as a spacer that forms a gap 5600 between the unit connecting member 56 and the heating unit 5a.

[0133] In this embodiment, the second biasing member 563 is disposed between the unit connecting member 56 and the duct forming member 541, and forms a gap 5600 between the unit connecting member 56 and the duct forming member 541.

[0134] When the unit moving mechanism 7 is in the biased state, the engagement of the engaging portion 562 with the unit connecting member 56 is released, and the second biasing member 563 elastically biases the duct forming member 541 toward the second side D22 while forming a gap 5600 (see FIG. 10). As a result, the heating unit 5a moves from the retracted position to the reference position, and is positioned at the reference position.

[0135] On the other hand, when the unit moving mechanism 7 is in the pulled state, the engaging portion 562 engages with the unit connecting member 56, and a force that pulls the duct forming member 541 toward the first side D21 in the second direction D2 acts on the duct forming member 541 from the shaft portion 561. This moves the heating unit 5a from the reference position to the retracted position.

[0136] The image forming apparatus 10 further includes a first direction biasing mechanism 8 attached to the inner surface of the cover member 102 (see FIGS. 7 and 8). The second support 55 of the fixing unit 5b has a protrusion 55a protruding from the lower surface of the second support 55 (see FIGS. 4 to 6).

[0137] The first directional biasing mechanism 8 comprises a spring 80, a spring case 81, and a cap portion 82 (see Figure 7).

[0138] The spring case 81 houses the spring 80. The cap portion 82 is attached so as to be movable relative to the spring case 81. The spring 80 is an example of an elastic member.

[0139] When the cover member 102 is located at the closed position, the spring 80 is sandwiched between the cover member 102 and the second support body 55 of the fixing unit 5b. In this embodiment, the spring 80 and the cap portion 82 are sandwiched between the cover member 102 and the second support body 55.

[0140] The spring 80 is sandwiched between the cover member 102 and the second support 55, and thereby urges the second support 55 by its elastic force in the mounting direction D12 (see FIG. 7). The mounting direction D12 is the opposite direction to the pull-out direction D11 of the fixing unit 5b.

[0141] Furthermore, when the cover member 102 is located at the closed position, the force that the second support member 55 receives from the spring 80 causes the protrusion 55a to come into contact with one beam pipe 12b of the lower support member 12.

[0142] The fixing unit 5b is positioned in the first direction D1 by the action of the spring 80 and the protrusion 55a. The first direction biasing mechanism 8 may be attached to the second support body 55 of the fixing unit 5b.

[0143] The first link member 731 moves along the first direction D1 in conjunction with the movement of the operating member 103. The first link member 731 is an example of a first direction link member.

[0144] The first link member 731 is arranged along the first direction D1 from the end of the main body 1 on the side where the operating member 103 is arranged in the first direction D1 to a position opposite the unit connecting member 56 (see Figures 7 and 8).

[0145] Therefore, the first link member 731 may obstruct the flow of air from one of the pair of fans 6 toward one of the pair of inlet openings 540b.

[0146] In this embodiment, one or more ventilation openings 731a are formed in a portion of the first link member 731 located between one of the pair of fans 6 and one of the pair of inlet openings 540b (see FIGS. 7 and 11). In the example shown in FIG. 11, a plurality of ventilation openings 731a are formed in the first link member 731.

[0147] The air sent out from one of the pair of fans 6 flows smoothly through the ventilation opening 731a toward one of the pair of inlet openings 540b.

[0148] The link mechanism 7x further includes a restriction frame member 738 having a through-hole 738a formed therein through which the first link member 731 passes in the first direction D1 (see FIG. 12). The restriction frame member 738 restricts movement of the first link member 731 in the second direction D2 and guides the first link member 731 along the first direction D1.

[0149] The regulating frame member 738 has a plurality of guide ribs 738b that protrude from the edge of the through hole 738a toward the through hole 738a (see Figure 12). The plurality of guide ribs 738b abut against the edge of the ventilation opening 731a in the first link member 731. As a result, when the first link member 731 moves along the first direction D1, the edge of the ventilation opening 731a in the first link member 731 slides against the plurality of guide ribs 738b.

[0150] The plurality of guide ribs 738b smoothly guide the first link member 731 along the first direction D1 without getting caught on the ventilation opening 731a.

[0151] [Notes on the Invention] The following is a summary of the invention extracted from the above-described embodiment. Note that the configurations and processing functions described in the following supplementary notes can be selected and combined as desired.

[0152] <Appendix 1> a main body having an exposure opening that exposes the inside to the outside; a fixing unit disposed inside the exposure opening in the main body along a first direction, the fixing unit including a fixing member to be heated and a pressure member to urge a sheet against the fixing member; a heating unit arranged in the main body along the first direction and aligned with the fixing unit in a second direction perpendicular to the first direction, the heating unit having a heater for heating the fixing member; An operating member that can be moved by being operated, Within the main body, a unit movement mechanism is positioned on the side of the heating unit in the second direction opposite to the fixing unit, and moves the heating unit between a reference position along the fixing unit and a retracted position further away from the fixing unit than the reference position, in conjunction with the movement of the operating member. a pair of fans arranged in the main body at an interval in the first direction on a side opposite to the heating unit side in the second direction with respect to the unit moving mechanism, and which blow air toward the heating unit; When the heating unit is in the retracted position, the fixing unit can be pulled out from inside the main body along the first direction. the heating unit includes a ventilation duct having a cavity formed along the first direction, a pair of inlet openings formed opposite the pair of fans and communicating with the cavity, and an outlet opening formed between the pair of inlet openings in the first direction and communicating with the cavity, The unit moving mechanism includes: a unit connecting member connected to the heating unit at a position between the pair of inlet openings in the first direction with a gap between the unit connecting member and the outlet opening; An image forming apparatus comprising a link mechanism for transmitting the movement of the operating member to the unit connecting member.

[0153] <Appendix 2> The operating member is positioned at one end of the main body in the first direction, The link mechanism includes: The main body includes a first direction link member which is arranged along the first direction from the end in the first direction on the side where the operating member is located to a position facing the unit connecting member, and which moves along the first direction in conjunction with the movement of the operating member, The image forming apparatus according to Appendix 1, wherein a ventilation opening is formed in the portion of the first directional link member located between one of the pair of fans and one of the pair of inlet openings.

[0154] <Note 3> The link mechanism includes: The first directional link member has a through hole formed through it in the first direction, and is equipped with a restricting frame member that restricts the movement of the first directional link member in the second direction. The regulating frame member has a plurality of guide ribs that protrude from the edge of the through hole toward the through hole and abut against the edge of the ventilation opening in the first directional link member, The image forming apparatus according to Appendix 2, wherein when the first direction link member moves along the first direction, the edge of the ventilation opening in the first direction link member slides against the plurality of guide ribs.

[0155] <Note 4> the main body has a cover member that is rotatable between a closed position that closes the exposure opening and an open position that opens the exposure opening, The cover member also serves as the operation member, The link mechanism moves the heating unit from the reference position to the retracted position when the cover member moves from the closed position to the open position. Furthermore, the link mechanism moves the heating unit from the retracted position to the reference position when the cover member moves from the open position to the closed position, as described in any one of the appendices 1 to 3 of the image forming apparatus.

[0156] <Note 5> 5. The image forming apparatus according to claim 1, wherein the heater is an electromagnetic induction heating type heating device. [Explanation of symbols]

[0157] 1: Main unit 4: Printing device 5: Fixing device 5a: Heating unit 5b: Fixing unit 6: Fan 7: Unit movement mechanism 7x: Link mechanism 8:First direction biasing mechanism 10: Image forming device 45: Transcription device 51: Heater 54: 1st support 55:Second support 56: Unit connecting member 71: Movable parts 72: First biasing member 73: First direction movement mechanism 101: Exposure aperture 102: Cover member 103: Operating member 540: Ventilation duct 540a: Cavity 540b:Inflow opening 540c: Discharge opening 541: Duct forming member 560:Connection mechanism 731: First link member (first direction link member) 731a: Ventilation opening 738: Regulating frame member 738a:Through hole 738b: Guide rib 5600: Gap

Claims

1. a main body having an exposure opening that exposes the inside to the outside; a fixing unit disposed inside the exposure opening in the main body along a first direction, the fixing unit including a fixing member to be heated and a pressure member for urging a sheet against the fixing member; a heating unit arranged in the main body along the first direction and aligned with the fixing unit in a second direction perpendicular to the first direction, the heating unit having a heater for heating the fixing member; an operating member that can be moved by being operated; a unit movement mechanism that is disposed in the main body on the opposite side of the fixing unit side with respect to the heating unit in the second direction, and that moves the heating unit between a reference position along the fixing unit and a retracted position that is farther away from the fixing unit than the reference position in response to movement of the operation member; a pair of fans arranged in the main body at an interval in the first direction on a side opposite to the heating unit side in the second direction with respect to the unit moving mechanism, and which blow air toward the heating unit; When the heating unit is in the retracted position, the fixing unit can be pulled out from inside the main body along the first direction, the heating unit includes a ventilation duct having a cavity formed along the first direction, a pair of inlet openings formed opposite the pair of fans and communicating with the cavity, and an outlet opening formed between the pair of inlet openings in the first direction and communicating with the cavity, The unit moving mechanism includes: a unit connecting member connected to the heating unit at a position between the pair of inlet openings in the first direction with a gap between the unit connecting member and the outlet opening; a link mechanism that transmits the movement of the operating member to the unit connecting member.

2. the operating member is disposed at one end of the main body in the first direction, The link mechanism includes: a first direction link member that is disposed along the first direction from an end of the main body on the side where the operating member is disposed in the first direction to a position facing the unit connecting member, and that moves along the first direction in conjunction with the movement of the operating member; 2. The image forming apparatus according to claim 1, wherein a ventilation opening is formed in the first directional link member at a portion located between one of the pair of fans and one of the pair of inlet openings.

3. The link mechanism includes: a restricting frame member having a through hole formed therein through which the first direction link member passes in the first direction, and restricting movement of the first direction link member in the second direction; the regulating frame member has a plurality of guide ribs that protrude from an edge of the through hole toward the through hole and abut on an edge of the ventilation opening in the first directional link member, 3. The image forming apparatus according to claim 2, wherein an edge of the ventilation opening in the first direction link member slides on the plurality of guide ribs when the first direction link member moves along the first direction.

4. the main body has a cover member that is rotatable between a closed position that closes the exposure opening and an open position that opens the exposure opening, The cover member also serves as the operation member, the link mechanism moves the heating unit from the reference position to the retracted position when the cover member moves from the closed position to the open position; 4. The image forming apparatus according to claim 1, wherein the link mechanism further moves the heating unit from the retracted position to the reference position when the cover member moves from the open position to the closed position.

5. 4. The image forming apparatus according to claim 1, wherein the heater is an electromagnetic induction heating type heating device.

Images