JPH09160467A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly execute a high-quality printing, to reduce the cost and to facilitate the handling by attaching an image forming processing unit, a transfer device and a paper carrying means to a supporting body in a specified positional relation and attachably/detachably attaching the supporting body to a specified position of a device main body. SOLUTION: Respective image forming processing units 11Y, 11M, 11C and 11BK, respective transfer devices 17Y, 17M, 17C and 17BK and a paper carrying means 20 are attached to a movable housing 31 functioning as the supporting body in a specified positional relation, and the housing 31 is attachably/ detachably attached to a specified position in the device main body 1. Namely, the respective image forming processing units 11Y, 11M, 11C and 11BK, the respective transfer devices 17Y, 17M, 17C and 17BK and the paper carrying means 20 are attached to the common housing 31 on the outside of the device main body 1 in a state where assembling error is reduced. Therefore, each photoreceptor 12 and a paper carrying belt 23 are accurately driven, so that the high-quality printing is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus capable of, for example, color printing, and more specifically, a plurality of image forming process units spaced apart in a sheet conveying direction,
A transfer device disposed at a position corresponding to the photoconductor of each image forming process unit and capable of executing the image forming process in cooperation with the image forming process unit, and a sheet of the photoconductor and the transfer device in sequence. The present invention relates to an image forming apparatus in which a sheet conveying unit that can convey a sheet is attached inside the apparatus main body.

[0002]

2. Description of the Related Art Conventionally, for example, as shown in FIG. 5, an image forming apparatus capable of color printing has image forming process units (11Y, 11M, 11C, 11C) for each color (yellow Y, magenta M, cyan C, black BK). 11BK) are arranged in a line in the paper transport direction at intervals. In addition, 1
9 is a fixing device.

The image processing unit 11Y is a photosensitive member 1.
2 and its peripheral devices (for example, a charging device, a developing device, a toner collecting device, a static eliminator, etc.), and are detachably attached to corresponding mounting positions in the apparatus main body 1. The other units (11M, 11C, 11BK) have the same configuration and are detachably attached to the corresponding attachment positions in the apparatus body 1. Each unit (11Y, 11M, 11C,
11BK) and transfer devices (17Y, 17M, 17C, 17BK) are provided at positions corresponding to the photoconductors 12, respectively.

Each image forming process unit (11Y, 1
Exposure devices (18Y, 18M, 18C, 18BK) are provided above the 1M, 11C, 11BK), respectively. Each of the exposure devices (18Y to 18BK) irradiates the laser beam while scanning it in the main scanning direction and draws an electrostatic latent image on each photoconductor 12 that rotates in the clockwise direction in FIG.

The paper in the paper cassette 3U (3D) is 1
The sheets are picked up one by one by the sheet feeding roller 4U (4D) and sent out, and the conveying roller 5U (5D) and the registration roller 6
The timing is adjusted by the cooperation with and the sheet is fed onto the sheet conveying belt 23 of the sheet conveying unit 20. The sheet is electrostatically attracted to the sheet transport belt 23 by the suction device 8.

Here, the paper carrying belt 23 is stretched around a driving roller 21 and a driven roller 22,
The drive roller 21 is driven to rotate in the counterclockwise direction in FIG. 5 so that the drive roller 21 rotates in the X direction and the sheets are sequentially transferred to the photoconductor 12 of each unit (11Y, 11M, 11C, 11BK) and the transfer device (17Y, 17M). , 17C, 17BK). Incidentally, 24 is a tension roller. Each unit (11Y to 11BK) and transfer unit (17Y to 17B)
The image forming process is executed by K) and the toner image is transferred onto the sheet.

The sheet on which the toner image is transferred is separated from the sheet conveying belt 23 by the driving roller 21, and
The toner image is fixed on the sheet through the fixing device 19. The sheet on which the toner image is fixed is discharged to the upper tray 7U or the lower tray 7D by the switching selection of the switching unit 71.

In such an apparatus, the color image data is theoretically separated for each color and the exposure device (18
Y, 18M, 18C, 18BK), each process unit (11Y, 11M, 11C, 11BK) and transfer unit (17Y, 17M, 17C, 17BK) form each color image on the paper, so full color Can be printed.

Here, in the image forming apparatus described above, as shown in FIG.
, The four image forming process units (1
1Y to 11BK) a common support (for example, the movable housing 3)
1P), the movable casing 31P can be mounted at a predetermined position (between the front frame 2F and the rear frame 2R) in the apparatus main body 1 via the slide portion (slide rail holding member 42, slide rail 41) and externally. It is configured so that it can be pulled out.

The front frame 2F has a movable casing 31.
An opening 2d for passing P is formed, and
A pair of positioning reference pins (9, 9) that can be fitted into positioning reference holes (49, 49) formed at both ends of the front frame 32F of the movable housing 31P are provided.

Further, on the rear frame 2R, four driving rotating bodies (for example, driving bevel gears 45P) are rotationally driven corresponding to the photosensitive drums 12 of the respective image forming process units (11Y, 11M, 11C, 11BK). It is possible. Each drive rotator (45P) is connected to a drive motor via a gear train or the like, and can be independently rotatably driven.

On the other hand, the movable casing 31P has four driven rotors (so as to engage with the respective drive rotors (45P) in a synchronously rotatable manner when they are positioned and held at a predetermined position in the apparatus body 1. For example, a driven bevel gear 46P) is provided.

Therefore, when each driving bevel gear 45P is rotationally driven, the photosensitive drum 12 of each unit (11Y to 11BK) is rotated.

[0014]

By the way, in the above-mentioned image forming apparatus, each image forming process unit (11
(Y, 11M, 11C, 11BK), the sheet conveying means 20, and the transfer device (17Y, 17M, 17C, 17BK) are not arranged in a regular mutual positional relationship, the sheet may be skewed. Paper jams occur, or the color of images printed on paper is misaligned.

Therefore, each image forming process unit (1
1Y, 11M, 11C, 11BK) and sheet conveying means 20
And a transfer device (17Y, 17M, 17C, 17BK) are arranged in a regular mutual positional relationship, a highly accurate positioning holding means is provided, and the positioning holding means is used carefully at the time of assembly or maintenance. The position adjustment work is being carried out. However, this is costly and
It is difficult to handle and there is a problem.

In view of the above circumstances, an object of the present invention is to provide an image forming apparatus capable of smoothly performing high quality printing, reducing costs, and being easy to handle.

[0017]

SUMMARY OF THE INVENTION The present invention is directed to a plurality of image forming process units spaced apart in the sheet conveying direction, and a plurality of image forming process units disposed at positions corresponding to the photoconductors of the image forming process units. A transfer device capable of executing an image forming process in cooperation with the forming process unit, and a paper transport means capable of sequentially transporting a sheet between each photoconductor and the transfer device by a sheet transport belt are mounted in the apparatus main body. In the image forming apparatus, each of the image forming process units, each of the transfer devices, and the sheet conveying means are mounted with a support having a predetermined positional relationship, and the support can be attached to and detached from a predetermined position of the apparatus main body. It is characterized by being installed.

In the invention of such a configuration, since each image forming process unit, each transfer device, and the sheet conveying means are mounted and integrated on a common support with a predetermined positional relationship, these are set to the regular positions. The number of parts for positioning and holding can be reduced, and the assembling error can be reduced. Further, the removal and the attachment can be performed together, and it is not necessary to adjust the positions of these components during maintenance.

Therefore, high-quality printing can be smoothly performed, cost can be reduced, and handling is easy.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 4, the present image forming apparatus has the same basic configuration as the conventional example (FIGS. 5 and 6), but each image forming process unit (11Y, 1
1M, 11C, 11BK) and each transfer device (17Y, 17B)
M, 17C, 17BK) and the sheet conveying means 20 are attached to the support (31) with a predetermined positional relationship, and the support (31) is detachably attached to a predetermined position in the apparatus main body 1. It has been configured.

The same components as those in the conventional example (FIGS. 5 and 6) are designated by the same reference numerals, and the description thereof will be simplified or omitted.

First, in the movable casing 31 as a support,
As shown in FIG. 2, each image forming process unit (11
(Y, 11M, 11C, 11BK) are mounted, and the transfer unit (17Y, 17M, 17C, 17BK) and the sheet conveying unit 20 are each unit (11Y to 11BK).
The photoconductor 12 is attached in a predetermined positional relationship.

Specifically, as shown in FIGS. 1 and 3, the front and rear frames (32F, 32R) of the movable casing 31 have respective image forming process units (11Y, 11).
M, 11C, 11BK), the drive roller 21 and the driven roller 22 forming the sheet conveying means 20 are rotatably attached at a predetermined distance in the sheet conveying direction, and each transfer roller (17Y, 17M). , 17
C, 17BK) are rotatably supported so as to be in pressure contact with the corresponding photoconductors 12 via the paper transport belt 23 that is stretched over both rollers (21, 22).

Each unit (11Y, 11M, 11
A through hole 13 is formed in the photoconductor 12 of C, 11BK), and a driven rotating body (for example, a spline shaft member 51) is directly connected to one end of the through hole 13. Also,
Each photoconductor 1 is attached to the rear frame 2R in the apparatus body (1).
A plurality of photoconductor rotation shafts 61 that can be fitted into the two through holes 13 are provided.

As shown in FIG. 3, each rotary shaft 61 of the photosensitive member is
The front frame 2F in the apparatus main body 1 is rotatably supported by bearings 58, and is rotatably driven by a rotation driving means (not shown). Then, each of the photoconductor rotary shafts 61 has a driving rotary body (for example, the spline hole member 5).
2) is mounted so as to be engageable with the driven rotating body (51).

Further, the drive roller 21 of the sheet conveying means 20
A driven rotating body (for example, a spline hole member 53) is attached to a shaft end of the rear frame 32R side. on the other hand,
A roller drive shaft 54 corresponding to the drive roller 21 is rotatably provided on the rear frame 2R, and the roller drive shaft 54 has a drive rotating body (for example, a drive rotating body engageable with the driven rotating body (53)). , A spline shaft member 55) is attached.

According to the image forming apparatus having such a configuration, each image forming process unit (11Y, 11M, 11C, 1
1BK) and each transfer device (17Y, 17M, 17C, 17B)
K) and the sheet transporting means 20 can be mounted on the common movable housing 31 outside the apparatus main body 1 with a small assembly error. Therefore, the position adjustment at the time of assembly can be easily performed.

In this way, each image forming process unit (11Y to 11BK) and each transfer device (17Y to 17BK)
The movable housing 31 in which the paper transporting means 20 and the paper transporting means 20 are mounted is provided with slide rails (41, 4) as shown by a two-dot chain line in FIG.
1) is mounted between the frames (2F, 2R) in the apparatus main body 1 so that the drive rotating body (52) provided on each photoconductor rotating shaft 61 is driven and directly connected to each photoconductor 12. Engage with the body (51).

Further, the driven rotary body (53) provided on the drive roller 21 engages with the drive rotary body (55) provided on the roller drive shaft 54.

Therefore, it is possible to accurately drive the photoconductors 12, the paper transport belt 23, etc. to perform high quality printing.

Further, each unit (11Y, 11M, 11
C, 11BK) and each transfer device (17Y, 17M, 17C,
17BK) and the sheet conveying means 20 can be detached and attached together, and sheet jam processing and maintenance can be performed quickly. In addition, the number of parts for positioning and holding these at regular positions is reduced.

As a result, high quality printing can be performed smoothly, cost can be reduced, and handling is easy.

[0033]

According to the present invention, each image forming process unit, each transfer device, and the sheet conveying means are mounted on a support so as to have a predetermined positional relationship, and the support is mounted at a predetermined position in the apparatus main body. Since it is detachably attached to each of the units, each unit or the like can be attached to a common movable housing outside the apparatus main body with a small assembly error. Therefore, the position adjustment at the time of assembly can be easily performed. Also, they can be removed and attached together, and paper jam processing and maintenance can be performed quickly. Moreover, the number of parts for positioning and holding each unit or the like at the proper position can be reduced. As a result, high-quality printing can be smoothly performed, cost reduction can be achieved, and handling becomes easy.

[Brief description of the drawings]

FIG. 1 is a perspective view for explaining an embodiment of the present invention.

FIG. 2 is a diagram showing a movable housing in which each image forming process unit, each transfer device, and a sheet conveying unit are similarly mounted.

FIG. 3 is a diagram showing how the movable housing is attached to the apparatus main body.

FIG. 4 is likewise a side sectional view for explaining the overall configuration.

FIG. 5 is a diagram illustrating a conventional configuration of an image forming apparatus.

FIG. 6 is a perspective view showing a movable housing in which each image forming process unit is mounted.

[Explanation of symbols]

11Y, 11M, 11C, 11BK Image forming process unit 12 Photoconductor 17Y, 17M, 17C, 17BK Transfer device 31 Movable housing (support)

Claims (1)

[Claims] 1. A plurality of image forming process units spaced apart in the sheet conveying direction, and a plurality of image forming process units arranged at positions corresponding to the photoconductors of the respective image forming process units and cooperating with the respective image forming process units. In an image forming apparatus in which a transfer device capable of performing an image forming process and a sheet transporting unit capable of sequentially transporting a sheet between a photoconductor and a transfer unit by a sheet transport belt are mounted in the apparatus main body, The image forming process unit, the respective transfer devices, and the sheet conveying means are mounted on a support so as to have a predetermined positional relationship, and the support is detachably attached to a predetermined position in the apparatus main body. Image forming apparatus.