Image forming device

Abstract

An object of the present invention is to provide an image forming device that can guide a sheet guide portion provided on a cover to an appropriate position even when a plurality of support portions in a main frame are arranged at relatively small intervals. A guide unit holding portion is formed at a position between two support portions in the long side direction of a fixing unit. When the main cover portion rotates from an open position to a closed position, a supported portion of a swinging guide unit moves from a position separated from the guide unit holding portion to a position in contact with the guide unit holding portion. In addition, the supported portion slides on the guide unit holding portion. The swinging guide unit is swung upward by the supported portion sliding on the guide unit holding portion, and then the swinging guide unit is held at a target position by the guide unit holding portion.

Description

Technical Field

[0001] The present invention relates to an image forming apparatus provided with a cover having a guide portion for guiding a sheet. Background Art

[0002] In the image forming apparatus, a pair of sheet guides disposed to face each other form a sheet conveyance path.

[0003] In addition, one of the pair of sheet guides may be provided on a cover that can open and close a part of the main body.

[0004] By opening the cover, the pair of sheet guides are separated, thereby making it possible to easily eliminate a jam in the sheet conveying path.

[0005] However, when the cover is closed, one of the pair of sheet guides provided in the cover needs to be properly positioned in the main body.

[0006] For example, it is conceivable to provide a guide mechanism for guiding a member provided on the cover to an appropriate position on a plurality of support columns of the main frame.

[0007] On the other hand, in order to reduce the size of the image forming apparatus, a plurality of support columns in the main frame may be arranged at relatively small intervals. In this case, it is difficult to ensure space for installing the guide mechanism on the plurality of support columns. Summary of the invention

[0008] An object of the present invention is to provide an image forming apparatus capable of guiding a sheet guide portion provided on a cover to an appropriate position even when a plurality of support columns in a main frame are arranged at relatively small intervals.

[0009] An image forming device according to one embodiment of the present invention comprises a main frame, a fixing unit and a main cover. The fixing unit comprises a fixing member heated by a heater and a pressure member for applying force to a sheet body to the fixing member, and is mounted on the main frame. The main cover is supported to be rotatable. The main frame comprises two pillars. The two pillars are arranged along a side surface forming one end of the short side direction of the fixing unit, namely a protective side surface, are formed along a longitudinal extension, and are arranged at intervals in the long side direction of the fixing unit. The main cover is supported to be rotatable between a closed position for covering the protective side surface of the fixing unit and an open position for opening the protective side surface of the fixing unit. The image forming device further comprises a swinging guide unit. The swinging guide unit comprises a post-fixing guide member for guiding the sheet body passing between the fixing member and the pressure member, and is supported by the main cover to be able to swing up and down. The fixing unit comprises a guide unit holding portion. The guide unit holding portion is formed at a position between the two pillars in the long side direction of the fixing unit. The swing guide unit has a supported portion that can contact the guide unit holding portion. When the main cover portion rotates from the open position to the closed position, the supported portion moves from a position separated from the guide unit holding portion to a position contacting the guide unit holding portion, and the supported portion slides on the guide unit holding portion. As the supported portion slides on the guide unit holding portion, the swing guide unit swings upward due to the force received from the guide unit holding portion, and then the swing guide unit is held at the target position by the guide unit holding portion.

[0010] According to the present invention, it is possible to provide an image forming apparatus capable of guiding a sheet guide portion provided on a cover to an appropriate position even when a plurality of support columns in a main frame are arranged at relatively small intervals.

[0011] This specification is presented in a simplified form, with appropriate reference to the accompanying drawings, to summarize the concepts described in the following detailed description. This specification is not intended to limit the important features and essential features of the subject matter described in the claims, nor is it intended to limit the scope of the subject matter described in the claims. In addition, the subject matter described in the claims is not limited to implementations that solve some or all of the disadvantages described in any part of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a diagram showing the configuration of an image forming apparatus according to an embodiment.

[0013] Figure 2 It is a diagram showing the structure of a fixing device in the image forming apparatus according to the embodiment.

[0014] Figure 3 It is a perspective view of a main body frame in the image forming apparatus according to the embodiment.

[0015] Figure 4 It is a side view of the peripheral parts of the fixing unit and the swing guide unit in the image forming apparatus according to the embodiment (with the main cover opened).

[0016] Figure 5 It is a plan view of the peripheral portions of the fixing unit and the swing guide unit in the image forming apparatus according to the embodiment (with the main cover opened).

[0017] Figure 6 It is a side view of the peripheral parts of the fixing unit and the swing guide unit in the image forming apparatus according to the embodiment (in a state where the main cover is halfway closed).

[0018] Figure 7 It is a side view of the peripheral parts of the fixing unit and the swing guide unit in the image forming apparatus according to the embodiment (in a state where the main cover is closed).

[0019] Figure 8 It is a plan view of the peripheral portions of the fixing unit and the swing guide unit in the image forming apparatus according to the embodiment (in a state where the main cover is closed). DETAILED DESCRIPTION

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following embodiment is an example of a specific embodiment of the present invention and does not limit the technical scope of the present invention.

[0021] [Configuration of Image Forming Apparatus 10]

[0022] The image forming apparatus 10 according to the embodiment includes a printing device 4 that performs a printing process for forming an image on a sheet 9 .

[0023] The printing device 4 performs the above-mentioned printing process by an electrophotographic method. The sheet 9 is an image forming medium such as paper or a sheet-like resin member.

[0024] like Figure 1 As shown, the image forming apparatus 10 includes a sheet conveying device 3 and a printing device 4 which are provided in a main body 1 .

[0025] The main body 1 includes a main body frame 1x and an exterior member 100 (see Figure 3 , Figure 5 , Figure 8 ). The exterior member 100 is mounted on the main frame 1x to cover the main frame 1x.

[0026] The main frame 1x is composed of a plurality of metal pipes (see Figure 3 The exterior member 100 is attached to the main frame 1 x. The exterior member 100 forms the exterior of the image forming apparatus 10 .

[0027] The printing device 4 includes one or more image forming units 4x, an optical scanning device 40, a transfer device 44, and a fixing device 5. The image forming unit 4x includes a drum-shaped photoreceptor 41, a charging device 42, a developing device 43, a drum cleaning device 45, and the like.

[0028] The sheet conveying device 3 includes a feeding device 31, a plurality of main conveying roller pairs 32, and a plurality of auxiliary conveying roller pairs 33. The sheet conveying device 3 also includes a driving device (not shown) for driving the feeding device 31, the plurality of main conveying roller pairs 32, and the plurality of auxiliary conveying roller pairs 33.

[0029] The delivery device 31 delivers the sheets 9 stored in the sheet storage section 2 to a main delivery path 301 in the main body 1 . The main delivery path 301 and a sub-delivery path 302 described later are paths for the sheets 9 .

[0030] The main conveying path 301 is a path that leads from an entrance facing the delivery device 31 to a discharge port 301 a via a registration position P1 , a transfer position P2 , and a fixing position P3 .

[0031] The plurality of main conveying roller pairs 32 convey the sheet 9 along the main conveying path 301. The plurality of main conveying roller pairs 32 include a registration roller pair 32a, a traction roller pair 32b, a discharge roller pair 32c, and the like.

[0032] In the present embodiment, the transfer position P2 is located above the registration position P1, and the fixing position P3 is located above the transfer position P2. In addition, the discharge port 301a is located above the fixing position P3.

[0033] The printing device 4 forms a toner image on the sheet 9 conveyed along the main conveying path 301. The toner image is an image using toner as a developer. The toner is an example of the granular developer.

[0034] Figure 1 The image forming apparatus 10 shown is a tandem color image forming apparatus. Therefore, the printing device 4 includes a plurality of image forming units 4x corresponding to the plurality of colors of toner.

[0035] In the present embodiment, the printing device 4 includes four image forming units 4 x corresponding to four colors, namely, yellow, cyan, magenta, and black.

[0036] In each image forming unit 4x, the photoconductor 41 rotates, and the charging device 42 charges the surface of the photoconductor 41. In addition, the optical scanning device 40 writes an electrostatic latent image on the surface of the photoconductor 41 by scanning with a light beam.

[0037] The developing device 43 develops the electrostatic latent image into the toner image by supplying the toner to the surface of the photoreceptor 41. The photoreceptor 41 is an example of an image carrier that rotates while carrying the toner image.

[0038] The transfer device 44 transfers the toner image onto the sheet 9 at the transfer position P2 of the main conveying path 301. The transfer device 44 includes an intermediate transfer belt 441, four primary transfer devices 442 corresponding to four image forming units 4x, a secondary transfer device 443, and a belt cleaning device 444.

[0039] Each primary transfer device 442 transfers the toner image on the surface of each photoreceptor 41 to the surface of the intermediate transfer belt 441 . Thus, the color toner image is formed on the surface of the intermediate transfer belt 441 .

[0040] The secondary transfer device 443 transfers the toner image formed on the intermediate transfer belt 441 to the sheet 9 at the transfer position P2 of the main conveyance path 301 .

[0041] When the image forming apparatus 10 is a monochrome image forming apparatus, the secondary transfer device 443 transfers the toner image on the photoreceptor 41 to the sheet 9 at the transfer position P2 .

[0042] The drum cleaning device 45 removes the waste toner remaining on the surface of the photoreceptor 41. The belt cleaning device 444 removes the waste toner remaining on the intermediate transfer belt 441.

[0043] The fixing device 5 heats and pressurizes the toner image on the sheet 9 at the fixing position P3 of the main conveying path 301 . Thus, the fixing device 5 fixes the toner image on the sheet 9 .

[0044] like Figure 2 As shown, the fixing device 5 includes a heater 51 , a fixing belt 52 , a fixing roller 520 , a pressure roller 53 , and a sheet separation member 5200 .

[0045] The fixing belt 52 is a flexible cylindrical member that encloses the fixing roller 520 . The fixing belt 52 is heated by the heater 51 .

[0046] The fixing roller 520 is a cylindrical member that supports the fixing belt 52 inside the fixing belt 52. The fixing roller 520 includes a cylindrical core shaft portion 521 and an elastic portion 522 formed on the outer periphery of the core shaft portion 521.

[0047] The fixing roller 520 is rotatably supported, and the fixing belt 52 is rotatable together with the fixing roller 520 .

[0048] The fixing belt 52 includes a conductive base material, an elastic layer formed on the outer periphery of the base material, and a release layer formed on the outer periphery of the elastic layer.

[0049] The heater 51 is disposed facing the outer peripheral surface of the fixing belt 52. In the present embodiment, the heater 51 is an electromagnetic induction heating device. The heater 51 heats the base material of the fixing belt 52 mainly by electromagnetic induction.

[0050] The pressure roller 53 is rotatably supported and has a cylindrical core shaft portion 531 and an elastic portion 532 formed on the outer periphery of the core shaft portion 531 , similarly to the fixing roller 520 .

[0051] The pressure roller 53 is driven to rotate by a driving device (not shown). The fixing belt 52 and the fixing roller 520 rotate in conjunction with the pressure roller 53 .

[0052] The fixing belt 52 heats the toner image formed on the sheet 9 . The pressure roller 53 presses the toner image toward the sheet 9 .

[0053] The fixing belt 52 is an example of a fixing member heated by the heater 51 . The pressure roller 53 is an example of a pressure member that urges the sheet 9 toward the fixing belt 52 .

[0054] When the sheet 9 is attached to the fixing belt 52 , the sheet separation member 5200 peels the sheet 9 from the fixing belt 52 .

[0055] The sub-conveying path 302 branches from a portion between the fixing position P3 and the discharge port 301a in the main conveying path 301. The sub-conveying path 302 merges with a portion of the main conveying path 301 upstream of the registration position P1.

[0056] The registration roller pair 32a is disposed at the registration position P1. The registration roller pair 32a temporarily stops the sheet 9 at the registration position P1 and then feeds the sheet 9 to the transfer position P2.

[0057] The pull-in roller pair 32 b pulls in the sheet 9 that has passed the fixing position P3 from the fixing device 5 , and further conveys the sheet 9 toward the discharge port 301 a .

[0058] The sheet 9 that has passed between the fixing belt 52 and the pressure roller 53 is conveyed by the take-up roller pair 32 b to the discharge roller pair 32 c .

[0059] The discharge roller pair 32c is disposed at the discharge port 301a. The discharge roller pair 32c rotates in the first rotation direction to discharge the sheet 9 having passed through the pull-in roller pair 32b from the discharge port 301a to the discharge tray 1a.

[0060] On the other hand, the discharge roller pair 32 c rotates in the second rotation direction to reverse and convey the sheet 9 . The discharge roller pair 32 c conveys the reversed sheet 9 from the main conveyance path 301 to the sub-conveying path 302 .

[0061] The sheet conveying device 3 further includes a first sheet guide member 35, a second sheet guide member 36, and a third sheet guide member 37 (see Figure 1 ).

[0062] The first sheet guide member 35 and the second sheet guide member 36 are disposed opposite to each other and form a part of the main conveyance path 301 . The second sheet guide member 36 and the third sheet guide member 37 are disposed opposite to each other and form a part of the auxiliary conveyance path 302 .

[0063] The surface of the second sheet guide member 36 that faces the first sheet guide member 35 is a first guide surface 36a (see Figure 1 , Figure 4 The surface of the second sheet guide member 36 that faces the third sheet guide member 37 is the second guide surface 36b (see Figure 1 , Figure 4 ).

[0064] In the following description, the portion of the main conveying path 301 from between the fixing belt 52 and the pressure roller 53 to the discharge roller pair 32c is referred to as a subsequent conveying path 3010. The subsequent conveying path 3010 is an example of a first conveying path. In addition, the auxiliary conveying path 302 is an example of a second conveying path branched from the first conveying path.

[0065] The first sheet guide member 35 and the first guide surface 36a form a part of the subsequent conveying path 3010. The first guide surface 36a forms a partition wall of a part of the subsequent conveying path 3010. The first guide surface 36a guides the sheet 9 after passing through the pull-in roller pair 32b toward the discharge roller pair 32c.

[0066] The second sheet guide member 36 is an example of a post-fixing guide member that guides the sheet 9 passing between the fixing belt 52 and the pressure roller 53 .

[0067] The discharge roller pair 32 c can discharge the sheet 9 guided by the first guide surface 36 a of the second sheet guide member 36 to the discharge tray 1 a .

[0068] The second guide surface 36b and the third sheet guide member 37 form a base end portion of the secondary conveyance path 302. The second guide surface 36b forms a partition wall of a portion of the secondary conveyance path 302. The second guide surface 36b guides the sheet 9 turned over by the discharge roller pair 32c rotating in the second rotation direction from the subsequent conveyance path 3010 to the secondary conveyance path 302.

[0069] For example, the discharge roller pair 32 c , the first sheet guide member 35 , and the third sheet guide member 37 are integrated into the discharge unit 34 . That is, the discharge unit 34 includes the discharge roller pair 32 c , the first sheet guide member 35 , and the third sheet guide member 37 .

[0070] The plurality of auxiliary conveying roller pairs 33 convey the sheet 9 along the auxiliary conveying path 302 . One of the plurality of auxiliary conveying roller pairs 33 sends out the sheet 9 from the auxiliary conveying path 302 to the registration position P1 of the main conveying path 301 .

[0071] When the sheet conveying device 3 conveys the sheet 9 twice along the main conveying path 301 using the sub-conveying path 302 , the printing device 4 executes a duplex printing process that forms images on both sides of the sheet 9 .

[0072] In this embodiment, the fixing device 5 is divided into a heating unit 5a and a fixing unit 5b (see Figure 4 , Figure 5 ).

[0073] The heating unit 5 a includes a heater 51 and a first support 54 . The fixing unit 5 b includes a fixing belt 52 , a fixing roller 520 , a pressure roller 53 , and a second support 55 .

[0074] The first support 54 is a member that supports the heater 51. The second support 55 is a member that supports the fixing belt 52, the fixing roller 520, and the pressure roller 53. The fixing belt 52 is supported by the second support 55 via the fixing roller 520.

[0075] The heating unit 5a, the fixing unit 5b and the discharge unit 34 are mounted on the main frame 1x. The fixing unit 5b is arranged beside the heating unit 5a (see Figure 4 ).

[0076] The plurality of metal pipes constituting the main frame 1x include two support portions 11 and two beam portions 12 (see Figure 3 ).

[0077] The two support portions 11 are formed along the longitudinal direction D3 and are arranged at a distance from each other in the first direction D1 (see Figure 3 The longitudinal direction D3 is the up-down direction. The first direction D1 is the long side direction of the fixing unit 5b attached to the main frame 1x.

[0078] Two support pillars 11 are formed to extend along the longitudinal direction D3 beside the fixing unit 5b (see FIG. Figure 4 ).

[0079] The first direction D1 is also a direction along the center line of rotation of the fixing belt 52 and the pressure roller 53. In the present embodiment, the first direction D1 is a depth direction of the image forming apparatus 10.

[0080] The two support columns 11 include a first support column 11a disposed on the front side of the image forming device 10, and a second support column 11b disposed on the back side of the image forming device 10 (see FIG. 1 ). Figure 3 , Figure 5 ).

[0081] The two beams 12 are formed to extend in the lateral direction below the heating unit 5a and the fixing unit 5b and are arranged at intervals in the first direction D1 (see FIG. 2 ). Figure 3 , Figure 5 ). The horizontal direction is the width direction of the image forming apparatus 10 .

[0082] The two beams 12 are connected to the two support pillars 11, respectively (see Figure 3 ). For example, the two beam portions 12 are connected to the two support portions 11 by welding, respectively.

[0083] The two beams 12 include a first beam 12a disposed on the front side of the image forming device 10, and a second beam 12b disposed on the back side of the image forming device 10 (see FIG. 1 ). Figure 3 , Figure 5 ).

[0084] The fixing unit 5b is disposed between the heating unit 5a and the two support columns 11 (see FIG. Figure 4 ).

[0085] The heating unit 5 a is placed on the two beam portions 12 in a state of being bridged between the two beam portions 12. Similarly, the fixing unit 5 b is placed on the two beam portions 12 in a state of being bridged between the two beam portions 12.

[0086] The heating unit 5a and the fixing unit 5b are placed on the two beams 12 (see FIG. 1 ) with their longitudinal directions along the first direction D1. Figure 5 , Figure 8 ).

[0087] The exterior member 100 has a first opening 101, a second opening 102, a main cover 6, and an auxiliary cover 103 (see Figure 1 , Figure 5 , Figure 8 ).

[0088] The first opening 101 is a portion where an opening is formed to open the protective side surface 55a of the fixing unit 5b (see Figure 5 , Figure 8 ). The protection side surface 55a is a side surface forming one end of the fixing unit 5b in the second direction D2.

[0089] The second direction D2 is the short side direction of the fixing unit 5b. The heating unit 5a and the fixing unit 5b are arranged in parallel along the second direction D2. The two support columns 11 are arranged along the protective side surface 55a (see Figure 4 ).

[0090] The second opening portion 102 is a portion in which an opening is formed to open one end of the fixing unit 5b in the first direction D1 (see Figure 5 , Figure 8 ).

[0091] The main cover 6 can open and close the first opening 101. For example, the main cover 6 is supported by the main frame 1x. Alternatively, the main cover 6 may be supported by an edge of the first opening 101 in the exterior member 100.

[0092] The main cover 6 is supported so as to be rotatable around a lower support shaft 6x (see Figure 1 The main cover 6 can be rotated between a closed position in which the protection side surface 55a of the fixing unit 5b is covered and an open position in which the protection side surface 55a is opened.

[0093] One of the pair of partition walls forming the auxiliary transport path 302 is formed on the inner side surface of the main cover portion 6 . In addition, a part of the plurality of auxiliary transport roller pairs 33 is arranged on the inner side surface of the main cover portion 6 .

[0094] When the main cover 6 is opened, one of the pair of partition walls forming the auxiliary conveying passage 302 is separated from the other. Thus, a jam in the auxiliary conveying passage 302 can be easily eliminated.

[0095] In addition, the second sheet guide member 36 is also disposed on the inner side surface of the main cover portion 6 (see Figure 1 , Figure 4 ). When the main cover 6 is opened, the second sheet guide member 36 is separated from the first sheet guide member 35 and the third sheet guide member 37. Thus, a jam in the subsequent conveying path 3010 can be easily eliminated.

[0096] The auxiliary cover 103 is supported so as to be able to open and close the second opening 102 (see Figure 5 ). The auxiliary cover portion 103 is supported by the edge portion of the second opening portion 102 in the exterior member 100. The auxiliary cover portion 103 is rotatably supported by a support shaft 103x.

[0097] By moving the heating unit 5a to a position away from the fixing unit 5b, the fixing unit 5b can be pulled out from the main frame 1x along the first direction D1 (see FIG. 1 ). Figure 5 ).

[0098] The fixing unit 5 b can be pulled out from the main frame 1 x when the auxiliary cover 103 is opened. The fixing unit 5 b is pulled out from the main frame 1 x through the second opening 102 to the outside of the main body 1 .

[0099] However, when the cover is closed, the second sheet guide member 36 provided in the main cover 6 needs to be properly positioned in the main body 1 .

[0100] For example, it is considered that a guide mechanism for guiding the second sheet guide member 36 provided in the main cover 6 to an appropriate position is provided in the two support columns 11 of the main frame 1x.

[0101] On the other hand, in order to reduce the size of the image forming apparatus 10 , the two pillars 11 in the main frame 1 x may be arranged at a relatively small interval. In this case, it is difficult to ensure space for providing the guide mechanism on the two pillars 11 .

[0102] The image forming apparatus 10 includes a structure for guiding the second sheet guide member 36 provided in the main cover 6 to an appropriate position even when two support pillars 11 are arranged at a relatively small interval. This structure will be described below.

[0103] The image forming apparatus 10 includes a swing guide unit 7 mounted on the main cover 6 (see Figure 1 , Figures 4 to 8 ). The swing guide unit 7 includes a second sheet guide member 36 and a unit support 70 .

[0104] The unit support 70 supports the second sheet guide member 36. The unit support 70 is supported by the main cover 6. The unit support 70 is supported so as to be able to rotate up and down around a lower support shaft 7x (see Figure 4 , Figure 6 ).

[0105] The fixing unit 5b has two column contact portions 552 and one or more guide unit holding portions 553 (see FIG. Figures 4 to 8 The two column abutment portions 552 are formed to face the side surfaces of the two support pillar portions 11 .

[0106] The two pillar contact portions 552 respectively contact the side surfaces of the two support pillars 11. The fixing unit 5b is sandwiched between the heater unit 5a and the two support pillars 11, and is positioned in the second direction D2.

[0107] The guide unit holding portion 553 is formed at a position between the two support pillars 11 in the first direction D1.

[0108] The guide unit holding portion 553 is a portion extending from the upper edge portion of the protection side surface 55a side of the fixing unit 5b to the upper surface of the fixing unit 5b. The guide unit holding portion 553 is a portion of the second support member 55 of the fixing unit 5b.

[0109] In this embodiment, the two guide unit holding portions 553 are formed at two locations spaced apart in the first direction D1 (see FIG. 2 ). Figure 5 , Figure 8 ).

[0110] The guide unit holding portion 553 contacts the swing guide unit 7 when the main cover portion 6 rotates from the open position to the closed position (see Figure 6 ). Thus, the guide unit holding portion 553 holds the swing guide unit 7 at the target position. Figure 6 In FIG. 1 , the support column 11 and the beam 12 are indicated by imaginary lines (two-dot chain lines).

[0111] Figure 7 This shows a state in which the main cover 6 is closed and the swing guide unit 7 is held at the target position by the guide unit holding portion 553 .

[0112] The swing guide unit 7 has a supported portion 71 that can come into contact with the guide unit holding portion 553. The supported portion 71 is a part of the unit support 70.

[0113] In this embodiment, the swing guide unit 7 has two supported portions 71 corresponding to the two guide unit holding portions 553 (see Figure 5 , Figure 8 ).

[0114] Next, the operation of the swing guide unit 7 when the main cover 6 is rotated from the open position to the closed position will be described.

[0115] When the main cover 6 rotates toward the closed position, the supported portion 71 moves from a position separated from the guide unit holding portion 553 to a position in contact with the guide unit holding portion 553 (see FIG. 5 ). Figure 4 , Figure 6 ). Then, the supported portion 71 slides on the guide unit holding portion 553 .

[0116] As the supported portion 71 slides on the guide unit holding portion 553, the swing guide unit 7 swings upward by the force received from the guide unit holding portion 553. After the swing guide unit 7 swings upward, it is held at the target position by the guide unit holding portion 553 (see Figure 7 ).

[0117] In addition, in the present embodiment, the discharge unit 34 has a first engaging portion 340 (see FIG. 1 ) which is concave and opens in the lateral direction. Figures 4 to 8 On the other hand, the unit support member 70 has a convex second fitting portion 72 (see Figures 4 to 8 ).

[0118] The first fitting portion 340 and the second fitting portion 72 are formed between the two support portions 11 in the first direction D1 (see Figure 5 , Figure 8 ).

[0119] In this embodiment, the first engaging portion 340 is formed at two locations spaced apart in the first direction D1 (see Figure 5 , Figure 8 ). The swing guide unit 7 has two second fitting portions 72 corresponding to the two first fitting portions 340 .

[0120] The first engaging portion 340 includes a recessed portion 341 opened in the lateral direction and a tapered surface 342 connected to the edge of the recessed portion 341 (see Figure 4 ).

[0121] When the main cover 6 is rotated from the open position to the closed position, the second fitting portion 72 is fitted into the recess 341 of the first fitting portion 340 (see Figure 7 , Figure 8 ). The tapered surface 342 guides the first fitting portion 340 toward the recessed portion 341 .

[0122] The second engaging portion 72 is engaged with the first engaging portion 340, thereby restricting the movement of the swing guide unit 7 in the longitudinal direction D3 and in the closing direction from the main cover 6 toward the discharge unit 34. As a result, the swing guide unit 7 is also held at the target position in the second direction D2.

[0123] In this embodiment, the image forming apparatus 10 includes a spring 60 supported by the swing guide unit 7 or the main cover 6 (see Figure 4 , Figure 7 The spring 60 urges the swing guide unit 7 toward the discharge unit 34 when the main cover 6 is in the closed position (see Figure 7 ).

[0124] The spring 60 urges the swing guide unit 7 toward the discharge unit 34 , thereby maintaining the fitted state between the first fitting portion 340 and the second fitting portion 72 .

[0125] In addition, the swing guide unit 7 may include the first fitting portion 340 , and the discharge unit 34 may include the second fitting portion 72 .

[0126] By adopting the image forming apparatus 10 , even when two support pillars 11 are arranged at a relatively small interval, a mechanism for guiding the second sheet guide member 36 to the appropriate target position can be realized.

[0127] The scope of the present invention is not limited to the above content, but is defined by the description of the claims, so it can be considered that the embodiments described in this specification are only illustrative, not limiting. Therefore, all changes that do not depart from the scope and limits of the claims, and contents that are equivalent to the scope and limits of the claims are included in the scope of the claims.

Claims

1. An image forming device, It is characterized in that include: Main frame; A fixing unit, comprising a fixing member heated by a heater and a pressing member for applying force to the fixing member, and mounted on the main frame; as well as The main cover is supported to be rotatable. The main frame has two support columns, which are arranged along a side surface forming one end of the short side direction of the fixing unit, namely a protection side surface, are formed to extend in the longitudinal direction, and are arranged at intervals in the long side direction of the fixing unit. The main cover is supported so as to be rotatable between a closed position for covering the protection side surface of the fixing unit and an open position for opening the protection side surface of the fixing unit. The image forming apparatus further includes a swing guide unit having a post-fixing guide member for guiding the sheet passing between the fixing member and the pressing member, and supported by the main cover so as to be able to swing up and down. The fixing unit includes a guide unit holding portion formed between two of the support pillars in the longitudinal direction of the fixing unit. The swing guide unit has a supported portion capable of contacting the guide unit holding portion. When the main cover rotates from the open position to the closed position, the supported portion moves from a position separated from the guide unit holding portion to a position in contact with the guide unit holding portion, and the supported portion slides on the guide unit holding portion. As the supported portion slides on the guide unit holding portion, the swing guide unit is swung upward by the force received from the guide unit holding portion, and then the swing guide unit is held at a target position by the guide unit holding portion.

2. The image forming apparatus according to claim 1, It is characterized in that The image forming apparatus further includes a discharge unit having a discharge roller pair capable of discharging the sheet passing between the fixing member and the pressing member to a discharge tray, and the discharge unit is mounted on the main frame. One of the discharge unit and the swing guide unit has a first engaging portion having a concave shape and opening in a lateral direction. The other of the discharge unit and the swing guide unit has a convex second fitting portion, and when the main cover portion rotates from the open position to the closed position, the second fitting portion is fitted into the first fitting portion. The first engaging portion and the second engaging portion are formed between the two supporting pillars in the longitudinal direction of the fixing unit. The second fitting portion is fitted into the first fitting portion, thereby restricting the swing guide unit from moving in the longitudinal direction and in the direction from the main cover portion toward the discharge unit.

3. The image forming apparatus according to claim 2, It is characterized in that The image forming device comprises: a first conveying path which is a conveying path for the sheet from between the fixing member and the pressing member to the discharge roller pair; and a second conveying channel branching from the first conveying channel, The post-fixing guide component comprises: a first guide surface forming a partition wall of a portion of the first conveying passage; and The second guide surface is formed on the rear side of the first guide surface and forms a partition wall of a part of the second transport path.

4. The image forming apparatus according to any one of claims 1 to 3, It is characterized in that The image forming device further includes an exterior member covering the main frame. The exterior component comprises: a first opening portion, which can be opened and closed by the main cover portion; a second opening portion opening one end of the fixing unit in the long side direction; and an auxiliary cover capable of opening and closing the second opening, The fixing unit can be pulled out from the main frame through the opening along the long side direction of the fixing unit.

Images