CN112445110A

CN112445110A - Framework of image forming device and assembling method thereof

Info

Publication number: CN112445110A
Application number: CN202010914462.XA
Authority: CN
Inventors: 梅野秀之
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 2019-09-04
Filing date: 2020-09-03
Publication date: 2021-03-05
Also published as: JP2021039251A; JP7331561B2

Abstract

The invention provides an assembling method of a framework (1) of an image forming device, which can maintain the position precision of components and can be easily assembled. An image forming apparatus (1) is provided with a plurality of head units (PH), and a head support (60), wherein the head support (60) is provided with an abutting plate (65) for abutting the front end parts of the plurality of head units, and a plurality of head reference axes (61) - (64) for positioning the mounting positions of the head units, the head support holds the plurality of head reference axes in parallel in a row, and the other components (40), (45) are positioned by using the head reference axes as a reference in an assembling method of a framework (1) of the image forming apparatus.

Description

Framework of image forming device and assembling method thereof

Technical Field

The invention relates to a framework of an image forming device and an assembling method thereof.

Background

In a conventional image forming apparatus having a plurality of image carriers, both ends of each image carrier are supported by two opposing flat surfaces of a frame via image carrier positioning members, and the image carrier positioning members can be arranged at arbitrary positions on the opposing flat surfaces (see, for example, patent document 1).

Patent document 1: japanese laid-open patent publication No. 2004-302194

In the conventional image forming apparatus, it is necessary to position the plurality of image carriers independently from each other, and since no reference for positioning is defined at this time, the position adjustment work is very difficult, and there is a problem that the work load is increased.

In addition, in the conventional image forming apparatus, the mounting position of the support reference member may be displaced due to loosening of screws caused by vibration during operation and conveyance and the weight of the developing cartridge.

In particular, in recent years, the image forming apparatus has been becoming larger with higher speed, and the above problem has become remarkable in the case of a large-sized image forming apparatus.

Disclosure of Invention

The invention provides a framework of an image forming device and an assembling method thereof, which can maintain the position precision of components and can be assembled easily.

In order to solve the above problem, a method of assembling a frame of an image forming apparatus according to the present invention,

the image forming apparatus includes a head support body having a backup plate for abutting front end portions of a plurality of head units and a plurality of head reference axes for positioning mounting positions of the head units, the head support body holding the plurality of head reference axes in a row in parallel,

the positioning of other components is performed with the reference axis of the print head as a reference.

In order to solve the above problem, the frame of the image forming apparatus of the present invention is characterized in that,

the printer head includes a head support body having a backup plate for butting front end portions of a plurality of head units and a plurality of head reference axes for positioning mounting positions of the head units,

the head support holds a plurality of head reference axes in parallel in a line, and includes a faceplate having a fitting hole fitted to the head reference axis, and performs positioning of the other member in a state of being positioned on the head reference axis.

According to the present invention, it is possible to position other components with high accuracy with reference to the reference axis of the print head, and to easily assemble the components.

Drawings

Fig. 1 is a perspective view of a skeleton of an image forming apparatus according to an embodiment of the invention.

Fig. 2 is a perspective view of the skeleton of the image forming apparatus viewed from a direction different from that of fig. 1.

Fig. 3 is a vertical sectional view of the mounting position of the caster on the base plate.

Fig. 4 is a perspective view of the print head support.

Fig. 5 is a view of the mounting state of the head unit to the head support body as viewed from the front.

Fig. 6 is an exploded perspective view of the head support body, the first panel, and the second panel.

Fig. 7 is a perspective view of the head support body in which the first panel and the second panel are assembled.

Fig. 8 is a perspective view of the head support in which the first panel and the second panel are assembled, as viewed from a direction different from that of fig. 7.

Fig. 9 is an explanatory view schematically showing the head support and the first panel.

Fig. 10 is a perspective view of a jig illustrating an assembly process of a skeleton of an image forming apparatus.

Fig. 11 is a perspective view of the jig following the assembly process of the framework of the image forming apparatus shown in fig. 10.

Fig. 12 is a perspective view of the jig following the assembly process of the framework of the image forming apparatus shown in fig. 11.

Fig. 13 is a perspective view of the jig following the assembly process of the framework of the image forming apparatus shown in fig. 12.

Fig. 14 is a rear view of the shaft support portion.

Fig. 15A is a front view showing the arrangement of the first print head reference axis in the process of assembling the framework of the image forming apparatus.

Fig. 15B is a side view showing the arrangement of the first print head reference axis in the process of assembling the framework of the image forming apparatus.

Fig. 16 is a schematic diagram illustrating an assembly process of a skeleton of the image forming apparatus.

Fig. 17 is a schematic view showing an assembly process of the skeleton of the image forming apparatus next to fig. 16.

Fig. 18 is a schematic view showing an assembly process of the skeleton of the image forming apparatus next to fig. 17.

Description of reference numerals: 1 … skeleton; 20 … a bottom panel; 21 … a caster wheel; 211 … mounting shaft; 22 … upper plate portion (first plate portion); 23 … lower plate portion; 24 … supporting the flat plate portion (second flat plate portion); 25 … support block; 26 … adjusting nut; 31 to 34 … pillars; 40 … a first panel; 41 … a body panel; 411 …; 412 … lower engagement hole; 42 … auxiliary panels; 421 … upper fitting hole; 422 … lower fitting hole; 423 to 426 … drive shaft fitting holes; 427 … transfer shaft fitting hole; 45 … a second panel; 451 … is provided with a fitting hole; 452 … lower fitting holes; 50 … a top plate; 60 … printhead support; 61-64 … printhead reference axis; 100 … clamp; 110 … platform; 111 … horizontal leg; 121-124 … upright setting parts; 130 … front support shelf; 140 … rear support; 150 … axle bearing; 151 … outer frame; 152 … support bracket (holding part); 153 … is inserted into the hole; 154 … position adjustment screw; PH … printhead unit.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the examples of the figures.

[ framework of image Forming apparatus ]

Fig. 1 is a perspective view of a frame 1 of an image forming apparatus according to the present embodiment, and fig. 2 is a perspective view of the frame as viewed from a different direction.

As shown in fig. 1 and 2, the framework 1 of the image forming apparatus includes a base plate 20, 4 support columns 31 to 34, a first panel 40, a second panel 45, a top plate 50, a head support 60, and the like.

The skeleton 1 is substantially rectangular in shape as a whole, and as shown in the drawing, the height direction thereof is the vertical direction of the skeleton 1, the longitudinal direction in a plan view is the horizontal direction of the skeleton 1, and the short direction in a plan view is the front-rear direction of the skeleton 1. In an ideal state where there are no assembly errors and component errors, in a state where the frame 1 is disposed on a horizontal plane, the vertical direction of the frame 1 is parallel to the vertical direction of the vertical line, and the horizontal direction and the front-rear direction of the frame 1 are horizontal.

In addition, the description of the posture, direction, and arrangement of each structure of the framework 1 is premised on a state in which the framework 1 is assembled with ideal accuracy in principle.

The posture and direction of each part of each structure are assumed to be in a state where the frame 1 is placed on a horizontal flat surface.

The base plate 20 is rectangular in plan view, and casters 21 are attached to the four corners of the lower side thereof.

Fig. 3 is a vertical sectional view of the mounting position of the caster 21 of the base plate 20. The 4 casters 21 are all mounted to the base plate 20 by the same support construction.

The bottom plate 20 has a hollow structure formed by a thin plate, and an upper flat plate portion 22, which is a horizontal first flat plate portion, faces a horizontal lower flat plate portion 23. The lower ends of the support columns 31 to 34 are fixedly attached to the upper surface of the upper plate portion 22 in a state of abutting against each other.

A support flat plate portion 24 is provided in an inner space between the upper flat plate portion 22 and the lower flat plate portion 23, and the support flat plate portion 24 is fixed to an upper surface of the lower flat plate portion 23 and serves as a horizontal second flat plate portion located between the upper flat plate portion 22 and the lower flat plate portion 23.

The caster 21 includes a mounting shaft 211 that faces in the vertical direction at the upper portion, and a male screw is formed on the outer periphery of the mounting shaft 211.

In the base plate 20, the upper portion of the support block 25, which is formed with a screw hole into which the mounting shaft 211 of the caster 21 is screwed, is disposed between the support flat plate portion 24 and the lower flat plate portion 23 in a state of being abutted against the lower surface of the support flat plate portion 24.

As described above, the caster 21 is supported by the support flat plate portion 24 separated from the upper flat plate portion 22 of the base plate 20 via the support block 25. Therefore, even when all the supporting objects are attached to the framework 1 and a heavy weight is applied, a load is not applied to the upper flat plate portion 22 of the bottom plate 20 but to the supporting flat plate portion 24, and therefore, the deflection of the upper flat plate portion 22 is suppressed, the inclination of the support columns 31 to 34 provided on the upper surface of the upper flat plate portion 22 is suppressed, and the positional accuracy of the supporting objects of the framework 1 is maintained high.

Further, an adjustment nut 26 abutting against a lower portion of the support block 25 is attached to the attachment shaft 211 of the caster 21, and the adjustment position can be fixed by tightening the adjustment nut 26 in a direction abutting against the support block 25 after the height adjustment is performed by the rotation of the attachment shaft 211.

Instead of the caster 21, the base plate 20 may be provided with a mounting shaft 211 having the same configuration as the caster 21 and a horizontal leg having an adjustment nut 26.

The support columns 31 to 34 are vertically erected along a vertical line from four corners of the upper surface of the upper flat plate portion 22 of the base plate 20. These support columns 31 to 34 are fixed by screwing in a state where the lower end portions thereof are abutted against the upper surface of the upper flat plate portion 22 of the bottom plate 20.

The top plate 50 is a rectangular flat plate having the same size as the flat plate surface of the bottom plate 20, and the upper ends of the support columns 31 to 34 are fixed to the lower surface thereof by screwing in a state of abutting against each other.

Fig. 4 is a perspective view of the head support 60. The head support body 60 includes a backup plate 65 that abuts the front end portions of a plurality of (e.g., 4) head units PH (see fig. 5), a plurality of (e.g., 4) head reference shafts 61 to 64 that position the mounting positions of the respective head units PH, and reference

shaft holding members

66 and 67 that fix the head reference shafts 61 to 64 to the backup plate 65.

The top backup plate 65 includes a main body portion 651 extending in the front-rear vertical direction, and a bent portion 652 bent at a right angle rightward from a lower end portion of the main body portion 651.

The body portion 651 is a long flat plate that is long in the vertical direction, and has mounting holes 653 for the respective head units PH.

Fig. 5 is a view of the mounting state of the head unit PH to the head support 60 as viewed from the front. The head unit PH is an exposure device that exposes the outer peripheral surface of a photosensitive drum, which will be described later, and stores therein a laser element as a light source for exposure and an optical system thereof.

Each head unit PH positions the head support 60 in a state where the left end surface is aligned with respect to each mounting hole 653 so as to abut against the right side plane of the main body 651, and the bottom portion abuts against the corresponding head reference shafts 61 to 64.

The 4 head units PH are formed corresponding to respective color images of yellow, magenta, cyan, and black, and the head units PH corresponding to yellow, magenta, cyan, and black are attached to the head support 60 in this order from above.

The reference

shaft holding members

66 and 67 are fixed to the front end portion and the rear end portion of the body portion 651 of the backup plate 65 by screwing.

Each of the reference

shaft holding members

66 and 67 is formed of a long metal thick plate that is long in the vertical direction. The insertion holes through which the 4 head reference shafts 61 to 64 are inserted in the reference

shaft holding members

66 and 67 are arranged in the vertical direction at predetermined intervals.

In general, when a member to be machined is large in size, machining accuracy tends to be remarkably reduced. Among them, the inventors of the present invention have found that the machining position accuracy of the hole can be maintained relatively high.

By utilizing this phenomenon, the head support body 60 forms the insertion holes of the 4 head reference shafts 61 to 64 in the reference

shaft holding members

66 and 67 with high positional accuracy, and forms the screw holes of the main body 651 to which the reference

shaft holding members

66 and 67 are attached with high positional accuracy.

Thus, the axial centers of the print head reference axes 61 to 64 are aligned with high accuracy in a straight line, and the print head reference axes 61 to 64 are aligned with high parallelism, and the print head reference axes 61 to 64 are horizontal, and the vertical intervals of the print head reference axes 61 to 64 are maintained at the target intervals with high accuracy.

In the frame 1, the partial

head reference shafts

61 and 64 held by the head support body 60 are used to perform positioning at the time of assembling the respective structures. For this positioning, 2

head reference shafts

61 and 64 located at the upper end and the lower end among the 4 head reference shafts 61 to 64 arranged in the vertical direction are used.

The 4 print head reference axes 61 to 64 are held in parallel in the front-rear direction, and are held so that the centers thereof are aligned on the same straight line along the vertical line in the vertical direction when viewed from the front. Further, the 2

head reference shafts

61, 64 are held longer in the front-rear direction than the other

head reference shafts

62, 63, and the end portions of each of the front and rear are projected forward and rearward than the other

head reference shafts

62, 63.

In addition, since both end portions of the

head reference shafts

61 and 64 are fitted into fitting holes of another member to be described later and positioned, chamfering is performed to facilitate insertion. The both ends of the

head reference shafts

61 and 64 are not limited to chamfering, and may be formed into other structures that can be easily inserted, for example, curved surface portions (radius of curvature).

Fig. 6 is an exploded perspective view of the head support body 60, the first panel 40, and the second panel 45, fig. 7 is a perspective view of a state in which these are assembled, fig. 8 is a perspective view seen from a direction different from that of fig. 7, and fig. 9 is an explanatory view schematically showing the head support body 60 and the first panel 40.

The first panel 40 has a rectangular flat plate shape as a whole, and is disposed on the rear side of the head support body 60 along the vertical direction and the horizontal direction.

The first panel 40 is composed of a main body panel 41 having a rectangular flat plate shape as a whole and having a large central opening, and a sub-panel 42 having a small rectangular flat plate shape provided so as to close the opening.

The body panel 41 is disposed with the front plane thereof abutting against the rear end portion of the head support body 60, and penetrates the upper fitting hole 411 and the lower fitting hole 412 in which the rear end portions of the

head reference shafts

61 and 64 are fitted.

The sub-panel 42 is disposed with the front side plane thereof abutting against the rear side plane of the main body panel 41, and penetrates through the upper fitting hole 421 and the lower fitting hole 422 in which the rear end portions of the

head reference shafts

61 and 64 are fitted.

In addition, drive shaft fitting holes 423 to 426 for performing insertion support of the rear end portion of the drum drive shaft of each photosensitive drum of the drum unit of 4 colors, not shown, and a transfer shaft fitting hole 427 for performing insertion support of the rear end portion of the intermediate transfer shaft of the intermediate transfer unit, not shown, are formed in the sub panel 42 of the first panel 40. The centers of the drum driving shafts of the respective photosensitive drums are required to be arranged in the vertical direction along the vertical line.

Although errors in the machining position accuracy of the upper fitting holes 411 and 421 and the lower

fitting holes

412 and 422 are suppressed, since it is almost difficult to set the errors to 0, the upper fitting holes 411 and 421 have a long hole shape in which the vertical width is slightly larger than the outer diameter of the

head reference shafts

61 and 64 and the horizontal width is substantially equal to the outer diameter of the

head reference shafts

61 and 64.

The inner diameters of the lower

fitting holes

412 and 422 substantially match the outer diameters of the

head reference shafts

61 and 64.

As described above, since the main body panel 41 and the auxiliary panel 42 are positioned by inserting the rear end portions of the two

head reference shafts

61 and 64 arranged with high accuracy, the first panel 40 including the main body panel 41 and the auxiliary panel 42 can be arranged on the plane in the vertical and horizontal directions with high accuracy with respect to the head support 60.

Further, since the main body panel 41 and the auxiliary panel 42 are independently and accurately arranged, the main body panel 41 and the auxiliary panel 42 can be arranged to face each other with high accuracy even on a plane in the vertical and horizontal directions.

Accordingly, the drive shafts of the photosensitive drums of the 4 color drum units and the intermediate transfer shaft of the intermediate transfer unit can be accurately arranged on the plane in the vertical and horizontal directions with respect to the head support body 60. Further, the centers of the drive shafts of the respective photosensitive drums can be arranged with high accuracy along the vertical direction of the vertical line.

Further, as described above, the vertical width of the upper fitting holes 411 and 421 of the main body panel 41 and the sub-panel 42 is set to be slightly larger than the outer diameter of the

head reference shafts

61 and 64, but the horizontal width substantially matches the outer diameter of the

head reference shafts

61 and 64, and therefore, the inclination in the horizontal direction can be suppressed. Further, the 4 color drum units can be arranged with high accuracy so as to be aligned vertically along the vertical line while suppressing the lateral inclination of the center of the drive shaft of each photosensitive drum in the direction of alignment.

The second panel 45 is formed in a rectangular flat plate shape as a whole, is disposed with the rear side plane thereof abutting against the front end portion of the head support body 60, and has an upper fitting hole 451 and a lower fitting hole 452 formed therethrough, into which the front end portions of the

head reference shafts

61 and 64 are fitted.

In the case of the second panel 45, the upper fitting hole 451 is also formed in an elongated hole shape having a vertical width slightly larger than the outer diameter of the

head reference shafts

61 and 64 and a horizontal width substantially equal to the outer diameter of the

head reference shafts

61 and 64. The inner diameter of the lower fitting hole 452 substantially matches the outer diameter of the

head reference shafts

61 and 64.

In the case of the second panel 45, since the distal end portions of the two

head reference shafts

61 and 64 arranged with high accuracy are inserted and positioned, the second panel 45 can be arranged on the plane in the vertical and horizontal directions with high accuracy with respect to the head support body 60.

In the case of the second panel 45, the vertical width of the upper fitting hole 451 is set to be slightly larger than the outer diameters of the

head reference shafts

61 and 64, and the horizontal width is substantially equal to the outer diameters of the

head reference shafts

61 and 64, so that the vertical error of the head support 60 and the second panel 45 can be allowed, and the horizontal inclination can be suppressed.

[ Clamp ]

Fig. 10 to 13 are perspective views of the jig 100 sequentially showing an assembly process of the frame 1 of the image forming apparatus.

As shown in fig. 10 to 13, the jig 100 includes a table 110, 4 upright portions 121 to 124, a front support 130, a rear support 140, a shaft support 150, and the like.

The posture and direction of each part of each configuration of the jig 100 will be described assuming that the vertical direction, the horizontal direction, and the front-rear direction of the frame 1 coincide with the vertical direction, the horizontal direction, and the front-rear direction of the jig 100, respectively, in a state where the jig 100 holds the frame 1 assembled with a desired accuracy.

The platform 110 is a base for supporting the upright units 121 to 124, the front support 130, and the rear support 140, and the bottom plate 20 of the support frame 1 is placed on a placement surface, which is the upper surface thereof.

The platform 110 has a plurality of horizontal legs 111 on the lower side thereof so that the mounting surface thereof is horizontal. Each horizontal leg 111 is attached with an attachment shaft that can be screwed into a screw hole provided in the lower surface of the platform 110, and an adjustment nut (both not shown) that abuts against the lower surface of the platform 110, and the adjustment position can be fixed by adjusting the height by rotating the attachment shaft and tightening the adjustment nut in a direction abutting against the lower surface of the platform 110.

Therefore, the inclination of the mounting surface of the platform 110 can be sufficiently reduced by adjusting the heights of the plurality of horizontal legs 111, and the platform can be adjusted to be horizontal.

The upright portions 121 to 124 are provided upright on the mounting surface of the platform 110 in the vertical direction along the vertical line, and can be adjusted in position in the front-rear and left-right directions with respect to the platform 110.

Each of the upright portions 121 to 124 is disposed adjacent to the support columns 31 to 34 of the frame 1. Further, the right side plane of the upright portion 121 faces the left side plane of the support 31, the left side plane of the upright portion 122 faces the right side plane of the support 32, the left side plane of the upright portion 123 faces the right side plane of the support 33, and the right side plane of the upright portion 124 faces the left side plane of the support 34. Further, three-point positioning protrusions protruding toward the support columns 31 to 34 are provided on the surfaces of the upright installation portions 121 to 124 facing the support columns 31 to 34. By abutting the facing surfaces of the struts 31 to 34 before assembly against the three-point positioning projections, the positions and orientations of the struts 31 to 34 can be appropriately adjusted.

The front support 130 is suspended and supported above two

upright portions

121 and 122 disposed on the front side of the platform 110. The front support 130 includes

extension projections

131 and 132 extending rearward from two positions, i.e., up and down, between the two

upright portions

121 and 122, and a shaft support 150 is provided at the front ends of the

extension projections

131 and 132.

The shaft support portion 150 provided at the distal end of the upper extension projection 131 supports the distal end portion of the head reference shaft 61, and the shaft support portion 150 provided at the distal end of the lower extension projection 132 supports the distal end portion of the head reference shaft 64.

The rear support frame 140 is suspended and supported above the two

upright portions

123 and 124 disposed on the rear side of the platform 110. The rear support frame 140 includes extension protruding portions (not shown) extending forward from two upper and lower positions between the two

upright portions

123 and 124, and a shaft support portion (not shown) is provided at each front end of the upper and lower extension protruding portions. The shaft support portion has the same structure as the shaft support portion 150 provided in the front support 130.

The shaft support portion provided at the front end of the upper extension projection supports the rear end portion of the head reference shaft 61, and the shaft support portion provided at the front end of the lower extension projection supports the rear end portion of the head reference shaft 64.

Fig. 14 is a rear view of the shaft support portion 150 as viewed from the rear. As shown in the drawing, the shaft support portion 150 includes a rectangular outer frame 151 provided at the distal end portions of the extending

protrusions

131 and 132, and a rectangular support frame 152 serving as a holding portion smaller than the outer frame 151 disposed inside the outer frame.

An insertion hole 153 into which the tip end portions of the

head reference shafts

61 and 64 can be inserted forward is formed in the center of the rear surface of the support frame 152. The insertion hole 153 has an inner diameter substantially equal to the outer diameter of the

head reference shafts

61 and 64, and can be inserted and held in a state of almost no gap.

The outer frame 151 surrounds the support frame 152 in the up, down, left, and right directions, and is provided with position adjusting screws 154 that abut against the support frame 152 from each of the up, down, left, and right directions. By rotating the 4 position adjustment screws 154, the support frame 152 can be adjusted in position relative to the outer frame 151 in the vertical direction along the axis-perpendicular plane.

Further, the position of the support frame 152 with respect to the outer frame 151 may be adjusted by inserting spacers in the vertical and horizontal directions.

The upper and lower shaft support portions provided on the rear support frame 140 are also configured similarly to the shaft support portion 150, and are supported by the outer frame so that a support frame formed with insertion holes into which the rear end portions of the

head reference shafts

61 and 64 can be inserted rearward can be adjusted in position in the upper, lower, left, and right directions.

Therefore, both ends of the

head reference shafts

61 and 64 can be supported by the shaft support portions 150 provided above and below the front support 130 and the shaft support portions provided above and below the rear support 140, and the movable range of each shaft support portion can be supported at any position, up, down, left, and right, as a limit.

[ method of assembling the skeleton ]

A method of assembling the frame 1 using the jig 100 will be described with reference to schematic explanatory views of fig. 10 to 13 and fig. 15A to 18.

First, as shown in fig. 10, the rear end portions of the

head reference shafts

61 and 64 held by the head support body 60 are positioned by the upper and lower

fitting holes

411 and 412 of the main body panel 41 of the first panel 40 and the upper and lower

fitting holes

421 and 422 of the auxiliary panel 42, and the front end portions of the

head reference shafts

61 and 64 are positioned by the upper and lower

fitting holes

451 and 452 of the second panel 45.

Further, the front end portions of the

head reference shafts

61 and 64 are inserted into the insertion holes 153 of the upper and lower shaft support portions 150 of the front support 130 of the jig 100, the rear end portions of the

head reference shafts

61 and 64 are inserted into the insertion holes of the upper and lower shaft support portions of the rear support 140 of the jig 100, and the head support 60, the first panel 40, and the second panel 45 are supported by the jig 100.

As shown in fig. 15A and 15B, the vertical and horizontal positions of the support frame 152 of the lower shaft support portion 150 of the front support frame 130 and the support frame of the lower shaft support portion of the rear support frame 140 are adjusted by the position adjustment screws 154 so that the axial center of the lowermost print head reference shaft 64 becomes the target height h1, and the print head reference shafts 64 are horizontal and parallel in the front-rear direction.

By the above adjustment, when the arrangement of the lowermost head reference shaft 64 is determined, the vertical and horizontal positions of the support frame 152 of the upper shaft support 150 of the front support frame 130 and the support frame of the upper shaft support of the rear support frame 140 are adjusted by the position adjusting screw 154 so that the axial center of the uppermost head reference shaft 61 is parallel to the axial center of the lowermost head reference shaft 64 and vertically above.

As described above, by appropriately arranging the head reference shaft 61 at the uppermost portion and the head reference shaft 64 at the lowermost portion of the head support body 60, the first panel 40 and the second panel 45 inserted therein are also appropriately arranged.

Further, since the sub panel 42 of the first panel 40 is provided with the drive shaft fitting holes 423 to 426 and the transfer shaft fitting hole 427, the drum drive shafts of the photosensitive drums of the 4 color drum units and the intermediate transfer shafts of the intermediate transfer unit can be positioned at appropriate positions.

Next, as shown in fig. 11 and 16, the base plate 20 is placed on the placement surface of the stage 110. Since the platform 110 is adjusted in advance so that the mounting surface becomes horizontal, the mounting shafts 211 of the 4 casters 21 are rotated so that the upper surface of the base plate 20 becomes horizontal and the target height h2 is set based on the mounting surface of the platform 110. After the bottom plate 20 is appropriately adjusted, the mounting shaft 211 is fixed by tightening the adjusting nuts 26 of the 4 casters 21.

In fig. 16 to 18, the abutting plate 65 and the second panel 45 of the head support body 60 are not shown.

Then, as shown in fig. 12 and 17, the support columns 31 to 34 are disposed on the upper surface of the base plate 20. At this time, the lower ends of the support columns 31 to 34 are arranged in a state of abutting against the upper surface of the base plate 20.

The support columns 31 to 34 are positioned so as to abut against three-point positioning projections provided on the upright portions 121 to 124 of the jig 100, and in this state, are fixed to the upper surface of the base plate 20 by screwing.

In addition, when each of the support columns 31 to 34 has a connection portion with the first panel 40 or the second panel 45, the connection portion is also connected.

Next, as shown in fig. 13 and 18, the remaining members such as the top plate 50 are attached. The top plate 50 is fixed by screwing in a state that the lower surface thereof abuts on the upper end portions of the respective pillars 31 to 34. In addition, when the top plate 50 has a connection portion to the head support 60, the first panel 40, or the second panel 45, the connection portion is also connected.

Thereby, the frame 1 of the image forming apparatus is assembled.

[ Effect of the embodiment ]

As described above, when the frame 1 is assembled, the first panel 40, the second panel 45, the drum driving shaft of the drum unit, the intermediate transfer shaft of the intermediate transfer unit, and other members are positioned with reference to the

head reference shafts

61 and 64 fixed to the head support body 60.

Therefore, the positioning of other members can be easily performed with reference to the

head reference shafts

61 and 64.

Further, since the reference axes 61 and 64 of the printing heads are used as references, the positioning of the other members can be performed by hole machining which can relatively easily obtain the machining position accuracy with respect to the increase in the size of the members, and the positioning of the members can be performed with high accuracy.

Further, since the above-described positioning operation of the other members is performed using the two

head reference shafts

61 and 64 located at the upper end portion and the lower end portion in the vertical arrangement direction among the plurality of head reference shafts 61 to 64, it is possible to perform positioning with higher accuracy with respect to the other members while suppressing an error caused by swinging about the

head reference shaft

61 or 64, unlike the case of performing positioning only by 1 head reference shaft.

In addition, when the frame 1 is assembled, since the positioning of other members such as the drum driving shaft of the drum unit and the intermediate transfer shaft of the intermediate transfer unit is performed in a state where the first panel 40 is positioned on the

head reference shafts

61 and 64 through the upper fitting holes 411 and 421 and the lower

fitting holes

412 and 422, more members can be accurately positioned with reference to the

head reference shafts

61 and 64.

Further, as described above, since the drum drive shaft of the drum unit and the intermediate transfer shaft of the intermediate transfer unit are positioned by the first panel 40, the components of the optical system involved in image formation are positioned with high accuracy, and the image quality of the image forming apparatus can be improved.

Further, since the positioning work of the various members described above is performed by using the jig 100 when assembling the frame 1, the arrangement, orientation, and the like of the members can be performed with higher accuracy, and the assembly can be performed with higher workability.

Further, since the holder of the jig 100, which holds the shaft support portions at both ends of the

head reference shafts

61 and 64 independently, can be adjusted in position in the vertical direction and the horizontal direction along the shaft vertical plane, the

head reference shafts

61 and 64 can be positioned in an appropriate state by freely adjusting the position, height, inclination, and the like of the

head reference shafts

61 and 64.

Further, since the jig 100 performs positioning of other members of the frame 1 in a state where the first panel 40 and the second panel 45 are positioned and held on the

head reference shafts

61 and 64, the mounting work of the first panel 40 and the second panel 45 can be easily performed and the assembling work can be efficiently performed, compared with a case where the first panel 40 and the second panel 45 are positioned after being positioned with respect to the

head reference shafts

61 and 64.

Further, when assembling the frame 1, the jig 100 is adjusted so that the two

head reference shafts

61 and 64 located at both ends in the vertical direction are aligned in the vertical direction, and thereafter, the other members are positioned, so that the other members to be positioned later can be aligned in the vertical direction specified in the frame 1 with high accuracy, and the occurrence of tilt errors of the respective structures with respect to the vertical direction can be effectively suppressed.

Further, when assembling the frame 1, after the jig 100 is adjusted so that both the two

head reference shafts

61 and 64 located at both ends in the vertical direction are horizontal, the positioning of the other members is performed, so that the other members located behind can be horizontally aligned with high accuracy in the front-rear direction (the direction along the head reference shafts) defined in the frame 1, and the occurrence of a tilt error of each structure with respect to the front-rear direction can be effectively suppressed.

Further, since the jig 100 includes the platform 110 having a horizontally adjustable mounting surface for mounting the bottom plate 20 of the frame 1, when the frame 1 is assembled, each configuration can be adjusted with the mounting surface of the platform 110 that is horizontal as a reference, and a tilt error of the entire frame 1 can be effectively suppressed.

In particular, by adjusting the level of the upper surface of the base plate 20 on the placement surface of the platform 110, it is possible to suppress a tilt error between the base plate 20 and the support columns 31 to 34 attached in a state of abutting against the upper surface thereof, and to suppress the tilt of the entire framework 1 more effectively.

Further, since the level of the upper surface of the base plate 20 of the framework 1 is adjusted by the caster 21 provided on the lower side thereof, the adjustment work can be easily performed.

In addition, since the vertical setting parts 121 to 124 are provided with the three-point positioning protrusions in order to adjust the orientation of the support columns 31 to 34 of the framework 1 in the vertical up-down direction, the orientation of the support columns 31 to 34 can be easily and accurately adjusted.

The frame 1 further includes a head support body 60 having a plurality of head reference shafts 61 to 64, and a first panel 40 for positioning other members such as a drum driving shaft of the drum unit and an intermediate transfer shaft of the intermediate transfer unit in a state of being positioned on the

head reference shafts

61 and 64 by the upper fitting holes 411 and 421 and the lower

fitting holes

412 and 422.

Therefore, when the arrangement of the head reference shafts 61 to 64 in the head support body 60 is manufactured with high accuracy, it is possible to arrange other members such as the drum drive shaft of the drum unit and the intermediate transfer shaft of the intermediate transfer unit with high accuracy, and it is possible to perform the assembling work easily and with high accuracy.

Further, for example, even when the image forming apparatus is increased in size, the frame 1 can form an image with high image quality.

Further, since the frame 1 is provided in a state where the lower end portions of the respective support columns 31 to 34 are abutted against the upper surface of the base plate 20, even when a large weight is applied to the structure on which the image forming apparatus is mounted, it is possible to suppress the occurrence of positional deviation in the vertical direction of the respective support columns 31 to 34 and maintain the positional accuracy of the components of the frame 1 and the structure of the image forming apparatus at a high level.

Further, since the bottom plate 20 of the framework 1 has the supporting flat plate portion 24 which supports the caster 21 from above separately from the upper flat plate portion 22 having the upper surface abutting against the support columns 31 to 34, even when a large weight is applied to the structure in which the image forming apparatus is attached to the framework 1, a load is not applied to the upper flat plate portion 22 of the bottom plate 20 but to the supporting flat plate portion 24, so that the deflection of the upper flat plate portion 22 can be suppressed.

Therefore, the positional accuracy of the object to be supported by the frame 1 can be maintained high while suppressing the occurrence of inclination of the support columns 31 to 34 provided on the upper surface of the upper flat plate portion 22.

Further, since chamfered portions are formed at both end portions of the

head reference shafts

61 and 64 included in the frame 1, when the

head reference shafts

61 and 64 are inserted and positioned, the insertion work can be easily performed, and the frame 1 having high workability can be provided.

[ others ]

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. The details shown in the embodiments can be appropriately modified without departing from the scope of the invention.

Claims

1. A method of assembling a frame of an image forming apparatus,

the frame of the image forming apparatus includes a head support having a backup plate for abutting the front end portions of the plurality of head units and a plurality of head reference axes for positioning the mounting positions of the head units,

the head support body holds a plurality of head reference axes arranged in parallel in a line,

2. The method of assembling a skeleton of an image forming apparatus according to claim 1,

the positioning operation of the other member is performed using two of the plurality of print head reference shafts aligned and held in a row and positioned at both end portions in the alignment direction.

3. The method of assembling a skeleton of an image forming apparatus according to claim 1 or 2,

the frame includes a face plate having a fitting hole fitted to the head reference shaft, and the other member is positioned in a state of being positioned on the head reference shaft.

4. The method of assembling a skeleton of an image forming apparatus according to claim 3,

the positioning work of the other members is performed using a jig.

5. The method of assembling a skeleton of an image forming apparatus according to claim 4,

the holding portions of the jig, which hold both end portions of the head reference shaft independently from each other, are each capable of position adjustment along a shaft vertical plane.

6. The method of assembling a skeleton of an image forming apparatus according to claim 4 or 5,

the positioning of the other member is performed in a state where the jig positions and holds the panel on the print head reference axis.

7. The method of assembling a frame of an image forming apparatus according to any one of claims 4 to 6,

the positioning of the other member is performed in a state where the two print head reference axes positioned at both end portions in the arrangement direction are held by the jig in a state of being arranged in the vertical direction.

8. The method of assembling a skeleton of an image forming apparatus according to claim 7,

the positioning of the other member is performed in a state where the jig holds both end portions in the arrangement direction so that the two print head reference axes positioned at both end portions are horizontal.

9. The method of assembling a frame of an image forming apparatus according to any one of claims 4 to 8,

the jig includes a table having a horizontally adjustable mounting surface on which a bottom plate of the frame is mounted.

10. The method of assembling a skeleton of an image forming apparatus according to claim 9,

a support column for supporting the panel is arranged on the upper surface of the bottom plate,

the level of the upper surface of the base plate is adjusted on the carrying surface of the platform.

11. The method of assembling a skeleton of an image forming apparatus according to claim 10,

the level of the upper surface of the base plate is adjusted by casters or horizontal legs provided on the lower side of the base plate.

12. The method of assembling a skeleton of an image forming apparatus according to claim 10 or 11,

the jig is adjusted so that the support column provided on the bottom plate of the frame faces in a vertical direction.

13. The method of assembling a frame of an image forming apparatus according to any one of claims 1 to 12,

the other components described above include a drum drive shaft of the drum unit.

14. The method of assembling a frame of an image forming apparatus according to any one of claims 1 to 13,

the other member includes an intermediate transfer shaft of the intermediate transfer unit.

15. A frame of an image forming apparatus is characterized in that,

the print head support includes a head support body having a backup plate for supporting a front end portion of the plurality of print head units and a plurality of head reference axes for positioning mounting positions of the plurality of print head units,

the positioning device is provided with a panel which has a fitting hole fitted to the print head reference shaft and performs positioning of other components in a state of being positioned on the print head reference shaft.

16. The framework of the image forming apparatus according to claim 15, comprising:

a base plate; and

a support column for supporting the panel on the base plate,

the support is provided in a state in which a lower end portion of the support abuts against an upper surface of the bottom plate.

17. The framework of an image forming apparatus according to claim 16,

the lower side of the bottom plate is provided with a caster or a horizontal foot,

the bottom plate has a second flat plate portion that supports the caster or the horizontal leg upright on a first flat plate portion having an upper surface that abuts against the pillar.

18. The framework of an image forming apparatus according to any one of claims 15 to 17,

chamfered portions or curved portions are formed at both end portions of the head reference shaft.