JP2005107109A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus with which simple exchange of image creation units is possible. <P>SOLUTION: Cylindrical bearings 48 of the four image creation units 32 are inserted into four grooves 76 of both side walls 7 of a casing 70. The casing 70 is pushed into a housing space 88 in the state of engaging the cylindrical bearings 48 of the image creation units 32 projecting from both the side walls 72 of the casing 70 with guide rails 94 of a guide plate 90. At the point of the time the cylindrical bearings 48 arrive at the ends of the guide rails 94, photoreceptors 38 of the image creation units 32 are installed in respective corresponding first transfer regions 28. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a copying machine, a printer, a facsimile machine, and an image forming apparatus having a combination of these functions. In particular, the present invention relates to an image forming apparatus including a plurality of image forming units.

2. Description of the Related Art Conventionally, an image forming unit in which image forming related elements such as a photoconductor and a developing device can be easily exchanged, or an image forming unit in which a plurality of elements are integrated is provided. An image forming apparatus is provided. For example, there is a color image forming apparatus in which a plurality of image forming units separately containing cyan, magenta, yellow, and black developers can be individually attached and detached. There has also been proposed an image forming apparatus in which a plurality of image forming units are accommodated in a single casing, and the casing can be attached to and detached from the main body (see, for example, Patent Document 1).
JP 2003-76106 A

  However, in an image forming apparatus in which a plurality of image forming units are housed in one casing, the plurality of image forming units are accurately positioned with respect to the casing, and then the casing is accurately positioned with respect to the image forming apparatus. There must be. That is, when each image forming unit is accurately placed when the image forming unit is accommodated in the housing, and when the housing containing a plurality of image forming units is accommodated in the main body, the housing is accurately placed in the main body. It is necessary to arrange. Therefore, not only a mechanism for positioning the casing on the main body but also a mechanism for accurately positioning each image forming unit with respect to the casing.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a configuration in which each image forming unit can be accurately positioned on the main body when the housing is mounted on the main body without accurately positioning the image forming unit on the main body. .

  An image forming apparatus that achieves the above object includes an image forming unit disposed to face a developer carrying surface that moves along a predetermined reference line, and is fixed to the main body of the image forming apparatus. And a pair of first guide portions that extend in a first direction at a first angle with respect to the reference line and guide both end support portions of the image forming unit, and are detachable from the main body of the image forming apparatus. And a pair of second guides formed in the housing and extending in a second direction at a second angle with respect to the reference line and guiding both end support portions of the imaging unit. And a guide portion. The pair of first guide portions includes a first restricting portion that restricts movement of both end support portions of the image forming unit, and the pair of second guide portions includes both end support portions of the image forming unit. A second restricting portion for restricting movement of Further, the first restricting portion and the second restricting portion cooperate with each other in a state in which the housing is mounted on the image forming apparatus to form a holding portion that holds both end support portions of the image forming unit. It is characterized by.

  An image forming apparatus that achieves the above-described object according to another aspect includes a plurality of image forming units arranged to face a developer carrying surface that moves along a predetermined reference line. A plurality of pairs of firsts fixed to the main body of the image forming apparatus and extending parallel to the first direction at a first angle with respect to the reference line and respectively guiding both end support portions of the plurality of image forming units. A guide portion, a housing that is detachably attached to the main body of the image forming apparatus, and is formed in the housing and extends in parallel with the second direction at a second angle with respect to the reference line, And a plurality of pairs of second guide portions that respectively guide both end support portions of the plurality of image forming units. Each of the plurality of pairs of first guide portions includes a first restriction portion that restricts movement of both end support portions of the image forming unit, and each of the plurality of pairs of second guide portions includes the image forming unit. A second restricting portion for restricting movement of the both end support portions. Further, the plurality of first restricting portions and the plurality of second restricting portions corresponding to the plurality of first restricting portions respectively support both ends of the plurality of image forming units in cooperation with each other in a state where the housing is mounted on the image forming apparatus. A plurality of holding portions that respectively hold the portions are formed along a line parallel to the reference line.

  According to the present invention, since the trouble of positioning the image forming unit and the housing can be saved, they can be easily replaced. Further, since a mechanism for positioning the image forming unit with respect to the housing is not required, the production cost is reduced.

  FIG. 1 shows a schematic configuration of an image forming apparatus (for example, a copier, a printer, a facsimile, or a multi-function machine having a combination of these functions). As shown in the figure, the image forming apparatus 10 includes an intermediate transfer device 14 at a substantially central portion of the housing 12. The intermediate transfer device 14 is wound around a roller 16, another roller 18 arranged in parallel at a predetermined distance from the roller 16 in the horizontal direction and the vertical direction, and these two rollers 16, 18. The endless transfer belt 20 is supported. One of the rollers 16 and 18 is drivingly connected to a motor (not shown) so that the transfer belt 20 rotates in the direction of the arrow 22.

  In the transfer belt 20, an upper belt portion 26 moving along a reference line 24 extending from the upper roller 18 toward the lower roller 16 passes through the four primary transfer regions 28 (28C, 28M, 268Y, 28K). The primary transfer roller 30 disposed inside the transfer belt 20 and the image forming unit 32 disposed outside the transfer belt 20 in each primary transfer region 28 (28C, 28M, 28Y, 28K). 32C, 32M, 32Y, 32K). Further, a secondary transfer region 34 is disposed at an appropriate position in the belt path from the transfer region 28C located on the most downstream side to the transfer region 28K located on the most upstream side with respect to the moving direction of the transfer belt 20. A secondary transfer roller 36 is disposed outside the belt 20.

  Each image forming unit 30 has a photoreceptor 38, which is disposed to face the intermediate transfer belt 20 in the primary transfer region 28. In this embodiment, a cylindrical photosensitive member is employed, but an endless belt photosensitive member may be employed. In addition, each image forming unit 32 includes a charging device 40 that charges the outer peripheral surface of the photoconductor 38 to a predetermined potential, and a developing device 42 that visualizes the electrostatic latent image formed on the outer peripheral surface of the photoconductor 38. It has. The developing devices 42 of the four image forming units 32 (32C, 32M, 32Y, 32K) contain cyan, magenta, yellow, and black developers, respectively. The photoconductor 38, the charging device 40, and the developing device 42 of each image forming unit 32 are integrally held by a frame 44 so that they can be integrally attached to and detached from a housing described later.

  In order to transmit the drive to the photosensitive member 38 and the developing device 42 supported by the frame 44, cylindrical bearings 48 are provided on both side walls 46 of the frame 44 facing both ends of the photosensitive member 38, as shown in FIG. The shaft 50 of the photosensitive member 38 is inserted into the cylindrical bearing 48. Further, on one end side of the photoreceptor 38, one end of the shaft 50 protrudes from the cylindrical bearing 48, and the engaging portion 52 is fixed to the protruding portion. Further, the shaft 50 of the photoreceptor 38 and the drive system of the developing device 42 are drivingly connected by a gear mechanism (not shown). Therefore, in a state where the image forming unit 32 is mounted on the image forming apparatus 10, driving is transmitted from the driving system of the image forming apparatus 10 to the shaft 50 of the photoreceptor 38 and the driving system of the developing device 42 via the engaging portion 52. it can.

  In addition, an exposure device 54 for forming an electrostatic latent image by irradiating an image on the outer peripheral surface of the photoreceptor 38 charged to a predetermined potential by the charging device 40 corresponding to each image forming unit 32 is formed. It is disposed above the image unit 32 (see FIG. 1).

  In the image forming apparatus 10 having such a configuration, an image is exposed from the corresponding exposure device 54 to the photoreceptor 38 of each image forming unit 32 to form an electrostatic latent image, and the image of the corresponding color is formed. It develops with the image development apparatus 42 provided with the developing agent. The developed image (developer image) is transferred to the intermediate transfer belt 20 that rotates in the direction of the arrow 22 in the primary transfer region 28 and is combined to form a target image (for example, a full-color image). On the other hand, the sheet is supplied from the paper supply unit 56, and the composite image is transferred in the secondary transfer region 34. Next, the sheet on which the image has been transferred is conveyed to a fixing device 58 where the image is fixed on the sheet and then discharged to a discharge tray 60.

  Next, a mechanism for attaching and detaching the four image forming units 32 will be described with reference to FIGS. As best shown in FIG. 7, the box-shaped housing 70 that detachably supports the four image forming units 32 includes two side walls 72 extending in parallel with the moving direction of the transfer belt 20, and these side walls 72. A connecting portion 74 to be connected is provided. As best shown in FIG. 5, the two side walls 72 have a longitudinal direction (first direction) intersecting the reference line 24 at a first angle to support a cylindrical bearing 48 protruding from the frame 44 of the imaging unit 32. A center line 78 (see FIG. 7) has four grooves (second guide portions) 76 (76C, 76M, 76Y, 76K) extending in the direction 2) that pass through the substantially center of the transfer belt 20 at equal intervals in the horizontal direction. )). The depths of the four grooves 76 (76C, 76M, 76Y, 76K) are different, and the line 82 connecting the lower end portions (second restricting portions) 80 thereof is parallel to the upper belt portion 26 of the transfer belt 20. (See FIG. 3). As shown in FIGS. 3 and 6, a positioning member (falling prevention portion) 84 is provided on the inner surface (opposing surface) of one or both side walls 72, and the image forming unit is formed by the positioning member 84 and the cylindrical bearing 48. 32 is stably held in the housing 70. Accordingly, the four image forming units 32 (32C, 32M, 32Y, 32K) drop the cylindrical bearings 48 protruding from the frames 44 into the grooves 76 (76C, 76M, 76Y, 76K) of the housing 70, thereby The image forming unit 32 is correctly positioned with respect to the housing 70 by the positioning members 84 corresponding to the grooves.

  As shown in FIG. 4, the housing 12 of the image forming apparatus 10 includes a door 86 on the left wall of the drawing in order to guide the housing 70 to which the plurality of image forming units 32 are mounted into the housing 12. A housing space 88 for housing the housing 70 is formed inside the door 86. The accommodation space 88 includes two guide plates (shown by dotted lines) 90 disposed on both ends of the intermediate transfer belt 20 and the rollers 16 and 18, and the housing 70 and the image forming unit are interposed between the guide plates 90. 32 is accommodated (see FIG. 7). As best shown in FIG. 4, these guide plates 90 extend parallel to the horizontal direction (first direction) from the vertical end 92 on the door 86 side, and intersect the reference line 24 at a second angle. Four guide rails (first guide portions) 94 (94C, 94M, 94Y, 94K) are provided symmetrically. The interval between the adjacent guide rails 94 in the vertical direction is equal to the height difference of the lower end portion 80 of the adjacent groove 76 formed in the housing 70. Further, the end portion (first restricting portion) 96 of each guide rail 94 has a line 98 connecting them parallel to the upper belt portion 26 of the intermediate transfer belt 20 and opens the door 86 of the image forming apparatus 10. In this state, the casing 70 on which the four image forming units 32 are mounted is connected to the guide rails 94 (94C, 94M, and 48C) at both ends of the cylindrical bearings 48 (48C, 48M, 48Y, 48K) protruding from the side wall 72 of the casing 70. 94Y, 94K) and are pushed into the accommodating space 88, the lower end portions 80 of the four grooves 76 and the end portions 96 of the four guide rails 94 overlap to form a holding portion 98 for holding the cylindrical bearing 48. (Refer to FIG. 5.) As a result, the photoreceptors 38 (38C, 38M, 38Y, 38K) of the image forming unit 32 are respectively placed in the first transfer regions 28 (28C, 28M, 28Y, 28K) shown in FIG. It is so as to location.

  In order to hold the housing 70 mounted in the accommodation space 88, it is preferable to provide a lock mechanism 100 near the entrance of the accommodation space 88 (see FIG. 6). The lock mechanism 100 can be constituted by, for example, a pin 102 slidably provided on the main body of the image forming apparatus 10.

  Further, in order to connect the photosensitive member 38 and the developing device 42 to the drive system in conjunction with the opening and closing of the door 86, the shaft of the photosensitive member 38 of each image forming unit 32 accommodated in the accommodating space 88 of the image forming apparatus 10 is used. 50, a drive shaft 110 and a connecting portion 112 that connects the engaging portion 52 of the shaft 50 and the drive shaft 110 are disposed (see FIGS. 2 and 7). The connecting portion 112 is connected to the door 86 by an appropriate link mechanism. The engaging portion 52 and the drive shaft 100 are connected with the door 86 closed, and the engaging portion 52 is opened with the door 86 opened. And the drive shaft 110 are separated.

  According to the image forming apparatus 10 configured as described above, when the four image forming units 32 are mounted on the image forming apparatus 10, first, 4 is provided in the housing 70 taken out from the accommodation space 88 of the image forming apparatus 10. Two image forming units 32 are attached. At this time, the cylindrical bearing 48 of the image forming unit 32 (32C, 32M, 32Y, 32K) is inserted into the four grooves 76 (76C, 76M, 76Y, 76K) of the side walls 72 of the housing 70. Next, the housing 70 is inserted into the accommodation space 88 of the image forming apparatus 10 with the door 86 opened. At this time, with the cylindrical bearing 48 of the image forming unit 32 (32C, 32M, 32Y, 32K) protruding from the both side walls 72 of the housing 70 engaged with the guide rail 94, the housing 70 is accommodated in the accommodation space 88. Push into. As a result, when the cylindrical bearing 48 reaches the end of the guide rail 94, the photoreceptors 38 of the image forming units 32 (32C, 32M, 32Y, 32K) are installed in the corresponding first transfer regions 28. The Finally, the lock pin 102 is fixed at the lock position, and the door 86 is closed. Accordingly, the connecting portion 112 connects the drive shaft 110 and the shaft 50 of the photosensitive member 38 via the link mechanism connected to the door 86. On the contrary, when the image forming unit 32 is replaced, the door 86 is first opened. As a result, the drive shaft 110 and the shaft 50 of the photoreceptor 28 are separated. Next, the lock pin 102 is removed. Then, the casing 70 is pulled out from the accommodation space 88 of the image forming apparatus 10 and the target image forming unit 32 is lifted out.

  Further, the holding portion for holding the cylindrical bearing of the image forming unit formed by the lower end portions of the four grooves of the housing and the end portions of the four guide rails of the guide plate may have a shape different from the above. . For example, as shown in FIG. 8, the lower end portions 202 (shown by solid lines) of the four longitudinal grooves 200 of the housing are the same as those of the housing 70, while the guide rail 204 of the guide plate is a door. It has a guide part 210 whose rail width 208 gradually decreases from the side (left side of the drawing) to its end part 206 and a restricting part 212 extending slightly downward compared to this guide part 210 (these are indicated by dotted lines). . The rail width 208 of the guide portion 210 in the vicinity of the door is larger than the diameter of the cylindrical bearing of the image forming unit. Therefore, it is easy to insert the cylindrical bearing of the image forming unit protruding from the side wall of the housing. Since the restricting portion 212 faces downward, it is closely engaged with the cylindrical bearing by the weight of the image forming unit itself. Therefore, the holding portion 214 formed by the lower end portion 202 of the groove 200 and the restricting portion 212 of the guide rail 204 shown in the drawing can hold the cylindrical holding portion of the image forming unit with high accuracy.

  As another form of the image forming apparatus of the present invention, the housing can hold an intermediate transfer device (including an intermediate transfer belt, a roller, and a primary transfer roller) (see FIG. 9). As a result, the intermediate transfer device can also be easily replaced.

  In addition, the photosensitive member and the developing device of the image forming unit can be individually unitized and held in the housing (see FIG. 10). For example, a photosensitive unit 300 in which an electrostatic latent image carrier (photoconductor), a charging unit, and a cleaning unit are unitized, and a developing unit 302 in which a developer carrier and a developer storage chamber are unitized are configured. The support portions at both ends held by the groove of the housing and the guide rail of the guide plate are a cylindrical bearing 304 through which the photosensitive member shaft is inserted, and the developing unit is a cylinder through which the developer carrier shaft is inserted. Each unit can be easily replaced by providing a groove and a guide rail corresponding to these cylindrical bearings.

  Further, a waste toner box (container box) that collects residual toner on the intermediate transfer belt (toner that remains on the intermediate transfer belt without being transferred to the sheet) is held in the housing in the same manner as the above various cartridges. It is also possible to make it.

  Further, the tip of the slot pair of the housing and the holding member may not be circular (see FIG. 11, the solid line is the groove of the housing, the dotted line is the guide rail of the guide plate), and may not be a groove or rail. It is. For example, as shown in FIG. 12, the cylindrical bearing 404 of the image forming unit can be held by the groove 400 of the housing and the staircase-shaped restricting portion (dotted line) 402 of the guide plate. In this case, the vertical side portion 406 of the staircase-shaped restricting portion of the guide plate presses the cylindrical bearing 404 of the image forming unit so as not to move upward along the groove 400 of the housing.

1 is a diagram illustrating a configuration of an image forming apparatus according to the present invention. It is sectional drawing of the one end side (side connected with a drive system) of the both-ends support part of an image forming unit. 3 is a side view of a housing 70. FIG. 2 is a diagram illustrating an image forming apparatus in a state where a housing 70 and an image forming unit 32 are not held. FIG. 2 is a diagram illustrating an image forming apparatus that does not hold an image forming unit 32. FIG. 2 is a diagram illustrating an image forming apparatus in a state in which a housing 70 and an image forming unit 32 are held. FIG. It is a front view of the component regarding attachment or detachment of the image forming unit in the image forming apparatus shown in FIG. It is a figure which shows the holding | maintenance part of another form. It is a figure which shows the housing | casing of another form. It is a figure which shows the housing | casing of another form. It is a figure which shows the holding | maintenance part of another form. It is a figure which shows the holding | maintenance part of another form.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus, 12 Housing, 14 Intermediate transfer apparatus, 16 Roller, 18 Roller, 20 Transfer belt, 22 Direction of arrow, 24 Reference line, 26 Upper belt part, 28 Primary transfer area, 30 Primary transfer roller, 32 Primary transfer roller 34 Secondary transfer region, 36 Secondary transfer roller, 38 Photoconductor, 40 Charging device, 42 Developing device, 44 Frame, 46 Side wall, 48 Cylindrical bearing, 50 Axis, 52 Engagement unit, 54 Exposure device, 56 Paper feed Section, 58 fixing device, 60 discharge tray,
70 housing, 72 side wall, 74 connecting part, 76 groove, 78 center line, 80 lower end part, 82 line, 84 positioning member, 86 door, 88 accommodating space, 90 guide plate, 92 end part, 94 guide rail, 96 terminal Part, 98 wires, 100 lock mechanism, 102 pins,
110 drive shaft, 112 coupling part,
200 groove, 202 lower end portion, 204 guide rail, 206 end portion, 208 rail width, 210 guide portion, 212 restricting portion, 214 holding portion,
300 Photosensitive unit, 302 Developing unit, 304 Cylindrical bearing, 306 Cylindrical bearing,
400 groove, 402 restricting part, 404 cylindrical bearing, 406 side part.

Claims (2)

In an image forming apparatus provided with an image forming unit disposed to face a developer carrying surface that moves along a predetermined reference line,
A pair of first guide portions that are fixed to the main body of the image forming apparatus and extend in a first direction at a first angle with respect to the reference line and guide both end support portions of the image forming unit;
A housing that is detachably attached to the main body of the image forming apparatus;
A pair of second guide portions formed in the housing and extending in a second direction with a second angle with respect to the reference line, and guiding both end support portions of the image forming unit;
The pair of first guide portions includes a first restricting portion that restricts movement of both end support portions of the image forming unit,
The pair of second guide portions includes a second restricting portion for restricting movement of both end support portions of the image forming unit,
The first restricting portion and the second restricting portion cooperate with each other in a state in which the housing is mounted on the image forming apparatus to form a holding portion that holds both end support portions of the image forming unit. An image forming apparatus. In an image forming apparatus including a plurality of image forming units arranged to face a developer carrying surface that moves along a predetermined reference line,
A plurality of pairs of firsts fixed to the main body of the image forming apparatus and extending parallel to the first direction at a first angle with respect to the reference line and respectively guiding both end support portions of the plurality of image forming units. The guide part of
A housing that is detachably attached to the main body of the image forming apparatus;
A plurality of pairs of second guide portions formed in the casing and extending in parallel with the second direction at a second angle with respect to the reference line and respectively guiding both end support portions of the plurality of image forming units. And
Each of the plurality of pairs of first guide portions has a first restricting portion that restricts movement of both end support portions of the image forming unit,
Each of the plurality of pairs of second guide portions has a second restricting portion for restricting movement of both end support portions of the image forming unit,
The plurality of first restricting portions and the plurality of second restricting portions corresponding to each of the plurality of first restricting portions cooperate with each other in a state in which the housing is mounted on the image forming apparatus to support both end support portions of the plurality of image forming units. An image forming apparatus, comprising: a plurality of holding portions that are respectively held along a line parallel to the reference line.

Images