Image formation apparatus

Abstract

To provide an image formation apparatus capable of supporting a conveyance unit with respect to a housing without twisting or distortion.SOLUTION: An image formation apparatus includes a conveyance unit 33 and a housing 3. The housing 3 includes side plates 13, 17, two reference shafts 25L, 25R, and two support plates 71L, 71R suspended from one ends of the two reference shafts 25L, 25R. The conveyance unit 33 includes two adjustment shafts 63L, 63R. One ends of the two adjustment shafts 63L, 63R are supported by the other side plate 17 on a lower side in a vertical direction at a predetermined interval from the other ends of the two reference shafts 25L, 25R. The other end of the one adjustment shaft 63R is supported by the one support plate 71R on the lower side in the vertical direction with the interval from one end of the reference shaft 25R. The other end of the other adjustment shaft 63L is supported by the other support plate 71R so as to be movable in an up and down direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus equipped with a transport unit. [Background technology]

[0002] An inkjet type image forming apparatus includes a transport unit that transports a recording medium along a predetermined transport direction, and an inkjet head that ejects ink onto the transported recording medium. To obtain good image quality, it is necessary to maintain a constant distance between the recording medium transported by the transport unit and the ink ejection surface of the inkjet head. Since the transport unit has a predetermined length along the transport direction, if the distance differs between the upstream side and the downstream side in the transport direction, color misregistration occurs.

[0003] In the image forming apparatus described in Patent Document 1, the conveyor belt unit (corresponding to the conveyor unit) is supported on the side plate of the housing at four points along the horizontal plane. Three of the four points are directly fixed to the side plate, and the remaining point is supported on the side plate so as to be adjustable in the height direction. By fixing the three points in this way to achieve flatness and then adjusting the remaining point, the conveyor belt unit can be supported on the housing without twisting or distortion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-168318 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the image forming apparatus described in Patent Document 1, the conveyor belt unit is supported on the housing through an opening on the top surface of the housing. Therefore, it is relatively easy to support the conveyor belt unit along a horizontal plane at three points. However, there are also cases where the conveyor belt unit is supported on the housing through an opening on the front surface of the housing. In such cases, the configuration of Patent Document 1 cannot be used.

[0006] The present invention has been made in consideration of the above circumstances and aims to provide an image forming device that can support a transport unit without twisting or distortion relative to the housing, even when the transport unit is supported on the housing through an opening on the front side of the housing. [Means for solving the problem]

[0007] In order to solve the above problem, the image forming apparatus of the present invention is an image forming apparatus comprising a transport unit that transports a recording medium along a predetermined transport direction, and a housing that detachably supports the transport unit, wherein the housing comprises a pair of side plates arranged opposite to each other in a direction intersecting the transport direction, two reference shafts fixed at the same height with a gap in the transport direction between the pair of side plates, and two support plates suspended from one end of the two reference shafts and fixed to one of the side plates, wherein the transport unit comprises two adjustment shafts fixed at the same height with a gap equal to the gap between the two reference shafts, one end of the two adjustment shafts is supported by the other side plate at a fixed gap in the vertical direction below the other end of the two reference shafts, the other end of one of the adjustment shafts is supported by one of the support plates at a gap in the vertical direction below one end of the reference shaft, and the other end of the other adjustment shaft is supported by the other support plate so as to be movable up and down.

[0008] In the present invention, one of the side plates may have an opening through which the transport unit is inserted and removed in the front-rear direction, and the two support plates may overlap a portion of the opening.

[0009] In the present invention, the other support plate may be provided with an adjustment member supported so as to be rotatable in the vertical direction, and a screw for rotating the adjustment member relative to the support plate, and the other end of the other adjustment shaft may be supported by the adjustment member and may be moved in the vertical direction by rotating the screw to rotate the adjustment member. Effect of the Invention

[0010] According to the present invention, even when the transport unit is inserted and removed from the housing along the front-to-rear direction, the transport unit can be supported horizontally at three points by providing left and right support plates that overlap part of the opening. Therefore, the transport unit can be supported by the housing without twisting or distortion, preventing color shift. [Brief description of the drawings]

[0011] [Figure 1] 1 is a front view showing a schematic internal configuration of an image forming apparatus according to an embodiment of the present invention; [Figure 2A] 1 is a front perspective view of a housing of an image forming apparatus according to an embodiment of the present invention; [Figure 2B] 1 is a perspective view of a housing of an image forming apparatus according to an embodiment of the present invention, as viewed from the rear. [Diagram 3] FIG. 2 is a perspective view showing a transport unit of the image forming apparatus according to the embodiment of the present invention. [Figure 4] 1 is a perspective view of a housing supporting a transport unit, as viewed from the front side, in an image forming apparatus according to an embodiment of the present invention; [Diagram 5] 1 is a perspective view of a housing supporting a transport unit, as viewed from the rear side, in an image forming apparatus according to an embodiment of the present invention; [Figure 6A] 4 is a front view showing the positional relationship between a reference shaft and an adjustment shaft in an image forming apparatus according to an embodiment of the present invention; FIG. [Figure 6B] 5 is a rear view showing the positional relationship between a reference shaft and an adjustment shaft in the image forming apparatus according to one embodiment of the present invention. FIG. [Figure 7A] FIG. 2 is a perspective view showing an adjustment member in the image forming apparatus according to the embodiment of the present invention. [Figure 7B] FIG. 2 is a cross-sectional perspective view showing an adjustment member in the image forming apparatus according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming apparatus according to an embodiment of the present invention will now be described with reference to the drawings.

[0013] First, the overall configuration of the image forming apparatus 1 will be described with reference to Fig. 1. Fig. 1 is a front view that shows a schematic view of the inside of the image forming apparatus 1. In each figure, L, R, Fr, and Rr respectively indicate left, right, front, and rear.

[0014] The image forming apparatus 1 is an inkjet type image forming apparatus that forms an image by ejecting ink. The image forming apparatus 1 includes a housing 3 having a rectangular parallelepiped hollow portion.

[0015] First, the housing 3 will be described with reference to Figures 2A and 2B. Figures 2A and 2B are perspective views showing the housing 3. The housing 3 has four support columns 5 arranged at the four corners (front left corner, front right corner, rear left corner, and rear right corner) of the hollow section, a rectangular upper frame body 7 connected to the upper ends of the four support columns 5, and a rectangular lower frame body 9 connected to the lower ends of the four support columns 5. The hollow section is divided into an upper hollow section S1 and a lower hollow section S2 by a partition plate 11 along a horizontal plane (see also Figure 1).

[0016] A front plate 13 is fixed to the front surface of the upper hollow section S1. More specifically, the front plate 13 is fixed to the upper frame 7 and the two front support columns 5. An opening 15 is formed in the front plate 13. A rear plate 17 is fixed to the rear surface of the upper hollow section S1. More specifically, the rear plate 17 is fixed to the upper frame 7, the two rear support columns 5, and the partition plate 11. In this way, the front plate 13 and the rear plate 17 face each other in the front-rear direction. The housing 3 has a bottom plate, a right side plate fixed between the right support columns 5, a left side plate fixed between the left support columns 5, and the like. Detailed explanations of these will be omitted.

[0017] Left and right upper through-holes 19L, 19R are formed at the same height at the left and right ends of the front plate 13. Left and right upper through-holes 21L, 21R are formed at the same height as the left and right upper through-holes 19L, 19R of the front plate 13 at the left and right ends of the rear plate 17. The left upper through-hole 19L and the left upper through-hole 21L are arranged coaxially along the front-rear direction. The right upper through-hole 19R and the right upper through-hole 21R are arranged coaxially along the front-rear direction.

[0018] As shown in FIG. 2B, left and right lower through-holes 23L, 23R are formed at the left and right ends of the rear plate 17 vertically below the left and right upper through-holes 21L, 21R at the same intervals.

[0019] A left reference shaft 25L is suspended between the left upper through hole 19L and the left upper through hole 21L. A right reference shaft 25R is suspended between the right upper through hole 19R and the right upper through hole 21R. The left and right reference shafts 25L, 25R (collectively referred to as reference shafts 25) are stepped shafts with small diameters at both ends. That is, the front end and rear end of the left reference shaft 25L are inserted into the left upper through hole 19L and the left upper through hole 21L, and the front end and rear end of the right reference shaft 25R are inserted into the right upper through hole 19R and the right upper through hole 21R. In this way, the left and right reference shafts 25L, 25R are fixed at the same height in a perpendicular and parallel posture to the front and rear side plates 13, 17.

[0020] 1, the upper hollow portion S1 of the housing 3 accommodates a head unit 31 and a transport unit 33. The head unit 31 is accommodated in an upper portion of the upper hollow portion S1, and the transport unit 33 is accommodated in a lower portion of the upper hollow portion S1. The lower hollow portion S2 of the housing 3 accommodates, for example, an ink container and a cleaning liquid container 35.

[0021] The head unit 31 will now be described. The head unit 31 is equipped with four inkjet heads 41 corresponding to yellow, black, cyan, and magenta inks. The inkjet heads 41 are equipped with three recording heads (not shown). The four inkjet heads 41 are arranged at predetermined intervals in the left-right direction.

[0022] The print head is equipped with a large number of nozzles (not shown) through which ink is supplied, and a piezoelectric element (not shown) provided for each nozzle. The nozzles have ejection openings on the bottom surface of the print head. When the piezoelectric element is driven, the ink in the nozzles is ejected downward from the ejection openings.

[0023] Next, the transport unit 33 will be described with reference to Figs. 1 and 3. Fig. 3 is a perspective view showing the transport unit 33. The transport unit 33 includes an endless transport belt 51, and a driving roller 53A and a driven roller 53B around which the transport belt 51 is wound. The transport belt 51 has a number of through holes penetrating in the thickness direction. The driving roller 53A and the driven roller 53B are rotatably supported by front and rear side plates 55 (see Fig. 3, not shown in Fig. 1). A handle 55a is formed on the front side plate 55. The transport belt 51 travels in the counterclockwise direction in Figs. 1 and 3 due to the rotation of the driving roller 53A. The recording medium is transported in the transport direction from right to left in Figs. 1 and 3 by the transport belt 51 traveling along the upper traveling track.

[0024] As shown in FIG. 1, a conveying plate 57, a plurality of suction chambers 59, and a plurality of suction devices 61 are arranged in the hollow portion of the conveying belt 51. The conveying plate 57 is arranged between the rollers 53A and 53B so as to contact the inner surface of the conveying belt 51 traveling along the upper traveling track. The conveying plate 57 has a plurality of through holes penetrating in the thickness direction. The plurality of suction chambers 59 are arranged below the conveying plate 57 along the conveying direction. The suction device 61 is arranged in the suction chamber 59 and generates a negative pressure in the suction chamber 59. When the suction chamber 59 becomes negative pressure, a negative pressure is generated in the through hole of the conveying plate 57 and the through hole of the conveying belt 51 traveling along the upper traveling track, and the recording medium is attracted to the conveying belt 51.

[0025] 3, left and right adjustment shafts 63L, 63R (collectively referred to as adjustment shafts 63) pass through the left and right ends of the front and rear side plates 55. The left and right adjustment shafts 63L, 63R are fixed at the same height and in parallel orientation perpendicular to the front and rear side plates 55. The adjustment shaft 63 is a stepped shaft with small diameters at both ends.

[0026] The conveying unit 33 is accommodated in the lower part of the upper hollow portion S1 of the housing 3 (below the head unit 31) through an opening 15 (see Figures 2A and 2B) in the front panel 13 of the housing 3, and is removably supported on the front panel 13 and rear panel 17 of the housing 3 via left and right adjustment shafts 63L and 63R.

[0027] Next, the transport unit 33 supported by the housing 3 will be described with reference to Fig. 4, Fig. 5, Fig. 6A, and Fig. 6B. Fig. 4 is a perspective view of the housing 3 supporting the transport unit 33, seen from the front side, and Fig. 5 is a perspective view of the housing 3 supporting the transport unit 33, seen from the rear side. Figs. 6A and 6B are diagrams for explaining the positional relationship between the reference shaft 25 and the adjustment shaft 63.

[0028] 5, the rear end portions of the left and right adjustment shafts 63L, 63R are inserted into left and right lower through-holes 23L, 23R formed in the rear plate 17 of the housing 3. On the other hand, as shown in Fig. 4, the front end portions of the left and right adjustment shafts 63L, 63R are supported by the front plate 13 of the housing 3 via left and right support plates 71L, 71R (collectively referred to as support plates 71), respectively.

[0029] The left and right support plates 71L and 71R will be described. First, the right support plate 71R will be described with reference to FIG. 4 and FIG. 6A. The right support plate 71R is substantially rectangular, and upper and lower through holes 81R and 83R are formed therein. The diameter of the upper through hole 81R is equal to the diameter of the front end of the right reference shaft 25R of the housing 3, and the diameter of the lower through hole 83R is equal to the diameter of the front end of the right adjustment shaft 63R of the conveying unit 33. As shown in FIG. 6A, the interval D between the upper and lower through holes 81R and 83R is equal to the interval D (see FIG. 6B) between the right upper and lower through holes 21R and 23R formed in the rear plate 17 of the housing 3.

[0030] As shown in FIG. 4 and FIG. 6A, the right support plate 71R is suspended from the front end of the right reference shaft 25R protruding from the upper through hole 19R of the front plate 13 of the housing 3. That is, the front end of the right reference shaft 25R is inserted into the upper through hole 81R of the right support plate 71R, so that the right support plate 71R is suspended from the front end of the right reference shaft 25R. Furthermore, the front end of the right adjustment shaft 63R of the transport unit 33 is inserted into the lower through hole 83R of the right support plate 71R. As a result, the front end of the right adjustment shaft 63R and the front end of the right reference shaft 25R are aligned vertically due to the weight of the transport unit 33. In this manner, the right support plate 71R is fastened to the front plate 13 of the housing 3 and the support column 5 while being suspended from the front end of the right reference shaft 25R. At this time, as shown in FIG. 6A, the right support plate 71R overlaps with a part (right end) of the opening 15 of the front side plate 13.

[0031] In this way, the front end of the right adjustment shaft 63R and the front end of the right reference shaft 25R are aligned vertically, so that the front end and the rear end of the right adjustment shaft 63R are positioned at the same height (a height that is a distance D below the upper through-hole 19R of the front plate 13 and the upper through-hole 21R of the rear plate 17). Furthermore, as described above, the rear end of the left adjustment shaft 63L is inserted into the left lower through-hole 23L formed in the rear plate 17 of the housing 3. The lower through-hole 23L is formed at a height that is a distance D below the upper through-hole 21L in the vertical direction. Therefore, the rear end of the left adjustment shaft 63L is also positioned at the same height as the front end and the rear end of the right adjustment shaft 63R.

[0032] Next, the left support plate 71L will be described with reference to FIG. 4 and FIG. 6A. The left support plate 71L is substantially rectangular, and has upper and lower through holes 81L and 83L formed therein. The diameter of the upper through hole 81L is equal to the diameter of the front end of the left reference shaft 25L of the housing 3, and the diameter of the lower through hole 83L is larger than the diameter of a washer 105 (described later) attached to the front end of the left adjustment shaft 63L of the conveying unit 33. As shown in FIG. 6A, the interval D between the upper and lower through holes 81L and 83L is equal to the interval D between the left upper and lower through holes 21L and 23L (see FIG. 6B) formed in the rear plate 17 of the housing 3.

[0033] Furthermore, the left support plate 71L is formed with a pin 85 extending forward on the left side of the lower through-hole 83L.

[0034] The left support plate 71L is suspended from the front end of the left reference shaft 25L protruding from the upper through hole 19L of the front panel 13 of the housing 3. That is, the front end of the left reference shaft 25L is inserted into the upper through hole 81L of the left support plate 71L, so that the left support plate 71L is suspended from the front end of the left reference shaft 25L. Furthermore, the front end of the left adjustment shaft 63L of the transport unit 33 is inserted into the lower through hole 83L of the left support plate 71L. The front end of the left adjustment shaft 63L protrudes from the lower through hole 83L and is supported by the left support plate 71L via the adjustment member 101.

[0035] Next, adjustment member 101 will be described with reference to Fig. 7A and Fig. 7B. Fig. 7A is a perspective view showing adjustment member 101, and Fig. 7B is a cross-sectional perspective view showing adjustment member 101. Adjustment member 101 is a rectangular parallelepiped member having substantially rectangular front and rear surfaces, upper and lower side surfaces, and left and right side surfaces.

[0036] The front and rear surfaces are provided with a front through hole 103 and a rear through hole 104, which are elongated holes extending horizontally and have different diameters, and are formed in a stepped shape in the axial direction on the same axis along the front-rear direction. The front end of the left adjustment shaft 63L protruding from the lower through hole 83L of the left support plate 71L is inserted into the front through hole 103 and the rear through hole 104. In detail, as shown in FIG. 7B, a cylindrical washer 105 having a larger diameter than the front end is coaxially fitted into the front end of the left adjustment shaft 63L protruding from the lower through hole 83L of the left support plate 71L. This washer 105 is inserted into the rear through hole 104. As shown in FIG. 7A, the front end of the left adjustment shaft 63L protrudes from the washer 105 and protrudes forward through the front through hole 103.

[0037] The adjustment member 101 has a fulcrum through-hole 106 that penetrates the front and rear surfaces to the left of the front and rear through-holes 103, 104, and is rotatably supported by a pin 85 formed on the left support plate 71L (see also Figs. 4 and 6A). Further, to the right of the front and rear through-holes 103, 104, a screw hole 107 is formed that penetrates the top and bottom surfaces. A screw 111 is screwed into the screw hole 107 from above. The lower end of the screw 111 protrudes downward from the lower plate.

[0038] A substantially horizontal fixed piece 113 is fixed to the left support plate 71L below the adjustment member 101. The lower end of a screw 111 that is screwed into a screw hole 107 of the adjustment member 101 abuts against the fixed piece 113. When the screw 111 is rotated in a screwing direction, the adjustment member 101 rises relative to the fixed piece 113 and rotates upward about the pin 85. On the other hand, when the screw 111 is rotated in a loosening direction, the adjustment member 101 descends relative to the fixed piece 113 and rotates downward about the pin 85.

[0039] By rotating the adjustment member 101 in this manner, the front end of the left adjustment shaft 63L moves up and down together with the washer 105 engaged with the rear through hole 104 of the adjustment member 101 within the lower through hole 83L of the left support plate 71L.

[0040] A cover plate 115 that covers a part of the front surface of the adjustment member 101 and the left side surface and lower side surface is fixed to the left support plate 71L.

[0041] As described above, the left support plate 71L is suspended from the front end of the left reference shaft 25L protruding from the upper through-hole 19L of the front plate 13 of the housing 3. As a result, the weight of the transport unit 33 causes the front end of the left adjustment shaft 63L and the front end of the left reference shaft 25L to be aligned vertically. In this state in which the left support plate 71L is suspended from the front end of the left reference shaft 25L, the left support plate 71L is fastened to the front plate 13 of the housing 3 and the support column 5. At this time, the left support plate 71L overlaps a part (left end) of the opening 15 of the front plate 13 of the housing 3.

[0042] A method for adjusting the horizontality of the transport unit 33 in the image forming apparatus 1 having the above configuration will be described. As described above, the front and rear ends of the right adjustment shaft 63R and the rear end of the left adjustment shaft 63L of the transport unit 33 are located at the same height. Therefore, the transport unit is fixed to the housing 3 at three points (the front and rear ends of the right adjustment shaft 63R and the rear end of the left adjustment shaft 63L) on the same horizontal plane.

[0043] On the other hand, the front end of the left adjustment shaft 63L is inserted into the lower through-hole 83L of the left support plate 71L. Since the diameter of the lower through-hole 83L is larger than the diameter of the washer 105 attached to the front end of the left adjustment shaft 63L, the front end of the left adjustment shaft 63L can move up and down and can be moved to the horizontal plane defined by the above-mentioned three points. Therefore, by rotating the screw 111 of the adjustment member 101 in either direction, the front end of the left adjustment shaft 63L moves up and down, and the conveying unit 33 can be supported horizontally at four points (the front and rear ends of the right adjustment shaft 63R and the front and rear ends of the left adjustment shaft 63L) without twisting or bending.

[0044] Thus, the front plate 13 and the rear plate 17 of the housing 3 are an example of one side plate and the other side plate in the present invention, and the front end and the rear end of the reference shaft 25 are an example of one end and the other end of the reference shaft in the present invention. Also, the front end and the rear end of the adjustment shaft 63 are an example of the other end and one end of the adjustment shaft in the present invention. Also, the left support plate 71L and the right support plate 71R are an example of the other support plate and one support plate in the present invention.

[0045] As described above, according to the present invention, even when the transport unit 33 is inserted or removed through the opening 15 in the front panel 13 of the housing 3, the transport unit 33 can be supported horizontally at three points by providing left and right support plates 71L, 71R that overlap part of the opening 15. Therefore, the transport unit 33 can be supported by the housing 3 without twisting or distortion, and color shift does not occur.

[0046] Next, an example of a method for mounting the transport unit 33 to the housing 3 will be described. First, the transport unit 33 is inserted into the upper hollow portion S1 through the opening 15 in the front plate 13 of the housing 3. Then, the rear ends of the left and right adjustment shafts 63L, 63R of the transport unit 33 are inserted into the left and right through-holes 23L, 23R in the rear plate 17 of the housing 3, respectively.

[0047] Next, the front ends of the left and right adjustment shafts 63L, 63R are inserted into the lower through-holes 83L, 83R of the left and right support plates 71L, 71R. Here, a washer 105 is attached in advance to the front end of the adjustment shaft 63L. In addition, an adjustment member 101 and a cover plate 115 are attached to the support plate 71L.

[0048] Then, the front ends of the left and right reference shafts 25L, 25R protruding from the front plate 13 of the housing 3 are inserted into the upper through holes 81L, 81R of the left and right support plates 71L, 71R. As a result, the left and right support plates 71L, 71R are suspended from the left and right reference shafts 25L, 25R. Then, due to the weight of the transport unit 33, the upper and lower through holes 81L, 83L of the left support plate 71L are aligned vertically, and the upper and lower through holes 81R, 83R of the right support plate 71R are aligned vertically. Then, the left and right support plates 71L, 71R are fastened to the housing 3. As a result, the transport unit 33 is fixed on the same horizontal plane at three points (the front end and rear end of the right adjustment shaft 63R and the rear end of the left adjustment shaft 63L).

[0049] Finally, the screw 111 of the adjustment member 101 is rotated in a predetermined direction to adjust the position of the front end of the left adjustment shaft 63L, thereby positioning the transport unit 33 horizontally.

[0050] In the above embodiment, the front end of the left adjustment shaft 63L of the transport unit 33 is adjustably supported by the adjustment member 101. In other words, since the right adjustment shaft 63R is fixed to the housing 3, the upstream end (right end) of the transport unit 33 in the transport direction is fixed to the housing 3. Generally, the recording medium is transported to the transport unit 33 from a paper feeder adjacent to the image forming apparatus. For this reason, by fixing the upstream end of the transport unit 33 in the transport direction to the housing 3, the receiving port for the recording medium from the paper feeder can be accurately positioned with respect to the paper feeder.

[0051] However, the front end of the right adjustment shaft 63R of the transport unit 33 or one of the rear ends of the left and right adjustment shafts 63L, 63R may be adjustably supported by the adjustment member 101.

[0052] The above-described embodiment is merely an example of the image forming apparatus according to the present invention, and the technical scope of the present invention is not limited to the above-described embodiment. [Explanation of symbols]

[0053] 1. Image forming device 3. Chassis 13 Front side panel (one side panel) 15 Aperture 17 Rear side plate (other side plate) 25L Left Reference Shaft 25R Right Reference Shaft 63L Left adjustment shaft 63R Right Adjustment Shaft 71L Left support plate (other support plate) 71R Right support plate (one side support plate) 105 Adjustment parts 111 Screw

Claims

1. An image forming apparatus including a transport unit that transports a recording medium along a predetermined transport direction, and a housing that detachably supports the transport unit, The housing includes: A pair of side plates arranged opposite to each other in a direction intersecting the conveying direction; Two reference shafts are fixed at the same height and spaced apart from each other in the conveying direction between the pair of side plates; two support plates suspended from one end of the two reference shafts and fixed to one of the side plates; The transport unit includes: two adjustment shafts fixed at the same height and spaced apart from each other by the same distance as the distance between the two reference shafts; one end of each of the two adjustment shafts is supported by the other side plate at a certain distance below the other end of each of the two reference shafts in the vertical direction, the other end of the one of the adjustment shafts is supported by one of the support plates at a position vertically below the one end of the reference shaft at the interval, the other end of the other adjustment shaft is supported by the other support plate so as to be vertically movable.

2. one of the side plates has an opening through which the transport unit is inserted and removed in a front-rear direction, 2. The image forming apparatus according to claim 1, wherein the two support plates overlap a portion of the opening.

3. The other support plate is An adjustment member supported so as to be rotatable in the vertical direction; a screw for rotating the adjustment member relative to the support plate, 2. The image forming apparatus according to claim 1, wherein the other end of the other adjustment shaft is supported by the adjustment member, and is movable in the vertical direction by rotating the screw to rotate the adjustment member.

Images