JP2003345221A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus in which a shaft support member accurately determines the position of the shaft center of a drum shaft of a photoreceptor drum mounted on an apparatus main body and the replacement workability of the shaft support member with respect to a side board of the apparatus main body can be improved. <P>SOLUTION: This image forming apparatus is provided with a drive unit 26 having the shaft support member 29 supporting the drum shaft 35 that rotates integrally with the photoreceptor drum 3 mounted inside the apparatus main body in a freely rotatable way, and the side board 23 fixed to a rear side of the apparatus main body is provided with a mounting part for mounting the drive unit 26 from the outside of the apparatus main body in a freely attachable and detachable way. <P>COPYRIGHT: (C)2004,JPO

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 such as a copying machine, a facsimile, a printer and the like, and more particularly to an image forming apparatus provided with a unit or member that can be attached and detached at the time of maintenance and inspection.

[0002]

2. Description of the Related Art Conventionally, there has been known an image forming apparatus having an image carrier such as a photoconductor drum which is detachably mounted, and the detachable image carrier is attached to the apparatus main body. Positional errors affect image formation. Particularly, in a tandem type color image forming apparatus including a plurality of image carriers,
This causes a positional shift between the image carriers, which causes a color shift.

In order to set the position of the image carrier at a predetermined position, a color image forming apparatus described in Japanese Patent Application Laid-Open No. 62-254159 has been proposed. This is because the shaft support member is fixed to the inner surface of the rear frame of the main body of the apparatus, and one end of the drum shaft, which is rotatably supported by the shaft support member, is directly connected to the motor located outside the rear frame. is doing. Further, a photosensitive drum as an image bearing member is rotatably supported on a box-shaped frame that is provided so as to be drawn out in parallel with the drum axis. Therefore, the motor drives the drum shaft to rotate the drum shaft together with the photosensitive drum. At the time of maintenance, the box-shaped frame is pulled out to the front side of the apparatus main body together with the photosensitive drum.

[Prior Art 2] An image forming apparatus using an electrophotographic system such as a copying machine, a printer, and a facsimile machine is capable of forming not only a single color image but also a multicolor image of two or more colors or a full color image. There is.

As a method of forming the color image,
For example, a plurality of photoconductors, which are image carriers capable of forming an image for each color obtained by color-separating an original image, are provided, and the image on the photoconductor is obtained according to the image information for each color obtained by color separation. To form a latent image on the latent image, to process the latent image with a developer of a color having a complementary color relationship, and to transfer the visible image from each photoreceptor to a transfer belt or There is a method of executing a step of superposing and transferring onto a transfer material such as plain paper carried on a belt. When the image is superposed and transferred on the transfer belt, the superposed and transferred image on the transfer belt is further collectively transferred onto a transfer material such as plain paper.

As a structure used for the above-mentioned image forming process, a photosensitive member for executing an electrophotographic image forming process, a charging device, a developing device, a transfer device and a cleaning device are combined into one unit (hereinafter referred to as "image forming unit"). ")), And the image forming units are provided in the image forming apparatus by the number corresponding to the colors obtained by color separation. As is well known, a developing device, which is one of the devices provided in the image forming unit, is a wet developing system that processes a latent image on a photoconductor by a electrophoresis using a developing solution. It may be adopted.

Further, the image forming unit is provided so as to be able to be taken in and out of the image forming apparatus so that it can be pulled out from the image forming apparatus at the time of maintenance and inspection such as replenishment of a developing solution and replacement of a photoconductor. It is configured.

Further, as an operation at the time of maintenance and inspection, there is an operation of releasing the cleaning device which is normally in contact with the photosensitive member. There is a configuration shown in FIG. 19 as a configuration that enables the cleaning device to be brought into and out of contact. In FIG. 19, a cleaning member C that is swingable via a fulcrum shaft B is provided above the drum-shaped photosensitive member A. The fulcrum shaft B is supported by the distal end portion in the extension direction of the arm-shaped support member D to which the base end is attached in the image forming unit. The installation position of the fulcrum shaft B depends on the internal structure of the cleaning member C. That is, the cleaning member C is the same as that shown in FIG.
As shown in (A), a trough-shaped accommodating portion P for accommodating the excess developer collected from the photoconductor A may be provided inside. As shown in FIG. 20 (B), at the position of the accommodation portion P, the collected developer liquid drops even when it is separated from the photoconductor A in order to insert and remove the photoconductor A (moved in the direction indicated by the arrow R1). It is set to a position where it can be prevented from coming off, and in the case of the configuration shown in FIG. 19, it is located on the side where the fulcrum axis B is provided. FIG. 20C shows (A).
The case where the position of the fulcrum shaft B1 is changed on the premise of the position of the recovery unit shown in FIG. 6 is shown. When the fulcrum shaft B1 is provided at such a position, the cleaning member C is set to the photosensitive member A.
When the developer is swung in the direction away from (moved in the direction indicated by the arrow R2), the developer is dripped from the recovery unit.

The cleaning device includes a cleaning member C.
It has a fulcrum axis B and can swing.
The cleaning member C is inserted through the fulcrum shaft B during non-cleaning such as when the cleaning member C is inserted or removed, as shown by an arrow S in FIG.
Is swingable in a direction away from the photoconductor A. The cleaning member C has a swinging end on the side where a space required to pull out the photoconductor A in the image forming unit is obtained. In the configuration shown in FIG. 19, an optical writing device (not shown) for the photoconductor A is used. The side opposite to the upper part of the developing tank GE corresponding to the area in which) is installed is defined as the swing end. As a result, when the photoconductor A swings away from the photoconductor A, the photoconductor A is inserted and removed in the direction indicated by the arrow W1.

The support member D, as shown in FIG.
An extension from the base end to the tip is arranged on the opposite side of the facing portion between the photoconductor A and the transfer portion corresponding to a position other than the facing position between the transfer portion and the photoconductor A in the image forming unit.
The support member D has, for example, a distal end portion in the extension direction of the outer peripheral surface of the photoconductor A so that the support member D does not interfere with the components provided in the image forming unit when the image forming unit is inserted into and removed from the apparatus main body. It is composed of a horizontal piece that is bypassed.

Further, as an operation at the time of maintenance and inspection, there is a replacement of the photoconductor. Normally, in the photoconductor, the end portion of the drive shaft is supported by the side plate provided in the housing portion of the image forming unit,
As the supporting structure, there is a structure shown in FIG. Figure 21
The support structure shown in Fig. 2 is based on the assumption that one end of the drive shaft of the photoconductor in the axial direction is supported by the main body of the device in advance, and is driven by mounting the image forming unit on the basis of the drive shaft. The axial end of the shaft is supported.

In FIG. 21, a flange F, which is mounted on the end surface of the photoconductor E and is supported by an end portion of the drive shaft G which is previously supported on the apparatus main body side on the opposite side to one end in the axial direction, is an image forming unit. When the side plate H is mounted on the drive shaft G, it is positioned and fitted to the end surface of the photoconductor E.

The drive shaft G of the photoconductor E is fixed to the side plate H of the image forming unit by being screwed into the nut member M mounted on the side plate H of the image forming unit at the other end in the axial direction. Supported by the state. The retaining structure is also provided on the flange F fitted to the end surface of the photoconductor E. In this case, the boss is rotatably supported by the bearing J mounted on the side plate H. A spring N arranged on the opposing surface of the member K and the flange F is used, and the flange F is moved by the elastic restoring force generated by the contraction of the spring N when the nut member M is screwed into the drive shaft G. It is adapted to be pressed against the end surface of the photoconductor E. The boss member K tries to move toward the nut member M side by the elastic restoring force of the spring N, but the nut member M prevents the movement, and in this state rotatably supports the drive shaft G.

Assembling of the photosensitive member E including the flange F with respect to the drive shaft G attached to the main body of the apparatus is as follows.
The procedure is as follows. Another flange (not shown), which is located at one axial end of the photoconductor E and faces the flange F, is fixed to the main body of the apparatus together with the rotating shaft G, and only the peripheral wall portion is formed for this flange. The cylindrical photosensitive member E is mounted. When the flange F is attached to the drive shaft G, the bearing J and the boss member K are attached to the bearing support holes formed in the side plate H of the image forming unit, and the spring N holds the flange F in a floating state. Then, the drive shaft G is inserted with the side plate H and the flange F corresponding to the position of the drive shaft G, and the nut member M is screwed into the shaft end.

[Prior Art 3] Further, conventionally, all or a part of an image carrier, a charging unit, a developing unit, a transfer unit, a cleaning unit, a charge eliminating unit and the like are integrated into one image forming unit, and the image forming is performed. It is known that the unit can be pulled out or inserted into the apparatus main body. The method of mounting the image forming unit on the apparatus main body includes mounting the image forming unit on a rail-shaped member such as a slide guide or a carriage that can be pulled out from the apparatus main body, and then pulling out and inserting the rail-shaped member from the apparatus main body. A method of pulling out and inserting the image forming unit in accordance with the above, and a convex groove or a concave groove that fits into the groove on the apparatus main body side are provided on the image forming unit side, and the groove is slid so that the image on the apparatus main body There is a method of pulling out and inserting the forming unit.

The former method of mounting the image forming unit on the rail-shaped member is adopted when the weight of the unit is relatively heavy, and the latter method tends to be adopted for the low cost and light weight image forming unit. It is in. In both methods, the image carrier is attached to the frame (side plate) of the image forming unit, and even if the image forming unit is pulled out from the apparatus main body,
The image carrier cannot be easily separated from the image forming unit.

Particularly in electrophotographic printers having a high printing speed, it is desired to shorten the response time for troubles and regular maintenance and inspection. Many of the sudden troubles should be dealt with immediately when the trouble occurs, and the best method is to completely replace the image forming unit. Periodic maintenance and inspections can be planned to secure time, but it is desirable to shorten the work. Therefore, it is preferable that the target portion or part can be appropriately opened. Particularly, in the case where the image forming unit is mounted on a rail-shaped slide guide, the image forming unit can be worked on the unit while being pulled out from the apparatus main body and mounted on the slide guide. It is preferable that the image forming unit can be easily separated from the slide guide mounting table to mount another image forming unit.

In order to be able to work on the image forming unit while it is still mounted on the slide guide, when the image carrier is stored in the image forming unit, the developing roller and the cleaning unit of the developing section are cleaned. It is difficult to observe and clean the condition of the blade. In this respect, as in the image forming apparatus disclosed in, for example, Japanese Patent Laid-Open No. 59-165073, the image carrier is mounted in the state where the image forming unit is pulled out from the apparatus main body and mounted on the slide guide. Since it can be taken out from the unit, such a problem can be avoided. Specifically, the above-mentioned JP-A-5
The image forming apparatus disclosed in Japanese Patent Application Laid-Open No. 9-165073 is provided with a U-shaped member in the unit so that the unit can be removed from the unit above the latent image carrier. The bearings attached to the central shaft portions that extend from the center of both end wall portions to both sides are received so that they can be lifted upward.

[0019]

[Problem 1] In the image forming apparatus shown in the above-mentioned prior art 1, when the photosensitive drum as an image holding member is pulled out from the apparatus main body together with the frame, the drum shaft is provided in the apparatus main body. It remains on the rear frame side. The drum shaft is supported by the shaft supporting member over a predetermined length in the axial direction, but since it is in a cantilever state, it is easily bent when an external force is applied, and the bearing portion of the shaft supporting member may be damaged. . However, since the shaft support member is attached to the inner surface of the rear frame located on the back side of the device main body, the work of attaching and detaching the shaft support member is performed in a narrow working space of the device main body, and the attaching and detaching workability is extremely high. bad.

[Problem 2] When the developing device adopting the wet developing method is used in the image forming apparatus shown in the above-mentioned prior art 2, the image forming unit is pulled out from the main body of the image forming apparatus or, conversely, is placed in the image forming apparatus. When the developer is inserted, the developer undulates in the developer tank and may overflow from the developer tank depending on the amount of the developer contained therein, and the overflowing developer may pollute the inside of the image forming unit. Therefore, it is conceivable to elevate the peripheral wall of the developing tank or to provide a lid on the upper surface of the peripheral wall and dispose a seal member between the lid and the peripheral wall. However, even if the peripheral wall is made high, the liquid level becomes high when the amount of the ink stored in the developing tank is large, so that a dramatic effect cannot be expected. Further, when the above seal member is used, there is a possibility that the developer may be exuded due to deterioration with time.

[Problem 3] Further, FIG.
In the configuration in which the cleaning device is separated from the photoconductor shown in (1), since the cleaning member C itself has the fulcrum shaft B, the swing amount of the cleaning member C is increased in order to insert and remove the photoconductor A from the image forming unit. There is a need to. If the swing amount is small, the space required for inserting and removing the photoconductor A cannot be formed. However, it is not preferable to provide a space for increasing the swinging amount of the cleaning member C within the limited space of the image forming unit, since this leads to an increase in size of the apparatus. In addition, the supporting member D supporting the fulcrum shaft B has a problem in bending rigidity due to the weight of the cleaning unit village C because the supporting position of the fulcrum shaft B is a horizontal piece.

The direction in which the photoconductor A is taken out from the image forming unit in FIG. 19 is indicated by an arrow W in FIG.
As shown by, the direction toward the upper part of the developing tank GE of the image forming unit is set. However, in such a taking-out direction of the photoconductor A, since an erasing member and a potential sensor (neither shown) used for image forming processing on the photoconductor A are located on the taken-out side, There is a problem that interference with each member is likely to occur.

[Problem 4] Further, FIG.
As shown in FIG. 3, in the configuration in which the image forming unit is mounted on the apparatus main body with the drive shaft of the photoconductor as a reference and the drive shaft is supported by the image forming unit, the bearing J to the side plate of the image forming unit and the boss. In addition to the mounting operation of the member K, the drive shaft G, the boss member K, and the nut member M must be aligned in a trial-and-error state, and there is a problem in that the attachment / detachment operation becomes very troublesome.

[Problem 5] In the image forming apparatus including the detachable image forming unit described in the related art 3 and the like, the image forming unit accommodates the image carrier and the rotating body such as the developing roller of the developing device. I often do it. Such a rotating body needs to be rotatably held at least in the state where the image forming unit is set in the apparatus main body.
As a structure for rotatably holding the rotating body in this way, like the image carrier in the image forming apparatus disclosed in Japanese Patent Laid-Open No. 59-165073 of the above-mentioned Prior Art 6, from the center of both end wall portions thereof. It is common to receive a central shaft portion extending on both sides via a bearing or the like. However, in this configuration, it is necessary to provide both end wall portions and both shaft portions on the rotating body itself, which is a replacement part, and it is also necessary to replace the bearings provided on this shaft portion as a unit. On the other hand, although it is not a rotating body housed in the image forming unit, for example, as a developing roller of a developing device in a general image forming apparatus, a hollow cylindrical body having one end wall portion opened is used. However, it is known that a holding member that engages with the opening portion of the hollow cylindrical body and holds the one side is provided on the apparatus main body side.

The present invention has been made in view of the above background, and a first object of the present invention is to accurately determine the position of the axis of the rotary shaft of the rotating body mounted on the apparatus main body by the shaft support member,
Moreover, it is an object of the present invention to provide an image forming apparatus capable of improving the workability of replacing the shaft support member with respect to the side plate of the apparatus body.

A second object of the present invention is to prevent developer from overflowing when the image forming unit having a developing device adopting the wet developing method is attached to or detached from the main body of the apparatus, thereby preventing the apparatus from being soiled. An object of the present invention is to provide an image forming apparatus having a configuration capable of preventing the above.

A third object is to provide an image forming apparatus having a structure capable of improving workability when attaching and detaching an image carrier mounted on the image forming unit.

A fourth object is to provide an image forming apparatus having a structure capable of improving workability when attaching and detaching the image forming unit to and from the apparatus body.

A fifth object is to use a hollow cylindrical body having at least one end wall portion opened as at least one rotating body housed in an image forming unit that can be pulled out and inserted into an image forming apparatus main body. By this, the cost of the rotating body to be a replacement part is reduced, and at the time of exchanging the rotating body, the holding member that engages with the opening portion and holds the inner side of the rotating body, and the opening portion. An object of the present invention is to provide an image forming apparatus that does not require the labor of separating the above.

[0030]

In order to achieve the first object, the invention of claim 1 is a shaft for rotatably supporting a rotary shaft which rotates integrally with a rotary body mounted in the main body of the apparatus. A drive unit having a supporting member is provided, and a side plate fixed to the back side of the apparatus body is provided with an attachment portion for detachably attaching the drive unit from the outside of the apparatus body. The rotating body includes an image carrier such as a photosensitive drum.

According to a second aspect of the invention, in addition to the rotating body,
2. A rotating member that is rotationally driven in the apparatus body.
In the image forming apparatus, the drive unit is provided with a rotation transmission device that transmits the rotation from the drive source to the rotating member. The drive source may be provided on the drive unit side or the apparatus main body side. Further, the rotating member includes a rotating body such as a developing roller used in a developing unit for developing the latent image formed on the image carrier.

According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, the side plate is provided with a positioning fitting portion into which the shaft support member is fitted. .

According to a fourth aspect of the present invention, in the image forming apparatus of the first, second or third aspect in which the drive unit is provided in the drive unit, the drive shaft directly connected to the drive source and the rotary shaft which are opposed to each other. A coupling member that is coaxially fitted to each other is formed at an end portion, and a coupling member that connects the drive shaft and the rotation shaft in a state where the fitting unit is fitted is provided. It is what

In order to achieve the second object, the invention of claim 5 is equipped with a wet developing device for developing a latent image formed on an image bearing member with a liquid developer, and the liquid developing device is mounted. In an image forming apparatus having an image forming unit that has an opening through which a part of the agent is exposed to the outside and is detachable from the apparatus main body, a liquid receiving groove is formed in the peripheral wall of the housing of the image forming unit. It is characterized by being formed.
When the wet type developing device is provided with a developing tank having an opening for exposing the liquid developer to the outside, the liquid receiving portion is provided at least at a portion of the peripheral wall corresponding to the opening of the developing tank. It is desirable to form a groove.

According to a sixth aspect of the present invention, in the image forming apparatus according to the fifth aspect, the liquid receiving groove is communicated with the liquid leak detection section.

According to a seventh aspect of the present invention, in the image forming apparatus according to the fifth aspect, a cover for covering the upper surface of the image forming unit is provided, and the end portion of the area for covering the upper surface of the image forming unit is the liquid. It is characterized in that it is positioned such that it enters into the receiving groove and the end is not in contact with the inner surface and the bottom of the liquid receiving groove.

In order to achieve the third object, the invention of claim 8 is provided with a detachable image carrier and a cleaning device provided so as to be able to come into contact with and separate from the image carrier, In an image forming apparatus configured such that the cleaning device is separated from the image carrier when the image carrier is attached and detached, the cleaning device is provided on the side opposite to the image transfer portion with the image carrier interposed therebetween. A swing fulcrum shaft positioned below the position where the rotary shaft of the image carrier is arranged, and an extension extending to a swing end to which a cleaning member is attached and which is swingably provided by the swing fulcrum shaft. And a supporting arm arranged opposite to the outer surface of the image carrier facing the image transfer portion.

In order to achieve the fourth object, the invention of claim 9 is an image forming apparatus comprising an image forming unit to which at least an image carrier is attached, which is detachably attached to the apparatus main body. A drive shaft of the image carrier previously attached to the apparatus main body, a slide guide into which the drive shaft attached to the side plate of the image forming unit can be inserted, and a slide guide in the axial direction of the drive shaft. A nut member movably supported and fastened to the drive shaft is provided, and the slide guide and the nut member are positioned coaxially with the axis of the drive shaft.

In order to achieve the above fifth object, the invention of claim 10 is an image forming apparatus having a unit that houses a rotating body and can be pulled out and inserted into the main body of the apparatus. A holding member configured by using a hollow cylindrical body having an open end wall portion on the rear side in the unit insertion direction and holding the rear side by engaging with the opening portion of the hollow cylindrical body is provided on the apparatus main body side. The unit is provided with an engaging portion that engages with the hollow cylindrical body from the rear side in the unit insertion direction when the unit is pulled out from the apparatus main body.

According to an eleventh aspect of the invention, in the image forming apparatus according to the tenth aspect, the engaging portion is provided so as not to come into contact with the rotating body when the unit is attached to the apparatus body. It is a thing.

The invention of claim 12 is the same as claim 10 or 1.
In the image forming apparatus of No. 1, the engaging portion is composed of a facing member facing the opening end surface on the rear side in the unit insertion direction, and when the unit is pulled out from the apparatus main body, the facing member is deep in the unit insertion direction. From the side, the receiving portion that receives the peripheral surface of the hollow cylindrical body end portion, which is released from the holding member by the holding member being released by continuing the pulling out of the unit in the state of being engaged with the hollow cylindrical body from the side, is the unit. And a pressing means for pressing the receiving portion and the end peripheral surface facing the receiving portion against each other.

According to a thirteenth aspect of the present invention, in the image forming apparatus according to the twelfth aspect, an operating member for restricting and releasing the restriction of the unit from the apparatus main body is provided, and the pressing means releases the pressing. It is configured such that the state and the pressed state can be selectively obtained, and in the apparatus main body set state of the unit, the pressing means is set to the released state of the pressing, and the restriction of the operation member is changed to the restriction. It is characterized in that interlocking switching means for switching the state of the pressing means from the released state of the pressing to the pressed state is provided in association with the operation for shifting to the release.

[0043]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] First, an embodiment of the invention according to claims 1 to 4 will be described with reference to FIGS. FIG. 1 shows the internal structure of an image forming apparatus P according to the first embodiment of the present invention. Image forming units 2 that form images of different colors are arranged along the rotation direction of the transfer belt 1 that is driven in the vertical direction. These image forming units 2 charge the surface of a photosensitive drum 3 as a rotating body driven clockwise by a charging unit 4, and the latent image forming unit 5 scans the charged portion with a laser beam to electrostatically charge the charged portion. After the latent image is formed, the electrostatic latent image is developed by the developing unit 6, and the developed image on the photosensitive drum 3 is transferred by the transfer unit 8 onto the transfer paper 7 as a transfer material that is conveyed by the transfer belt 1. The residual toner remaining on the photosensitive drum 3 is cleaned by the cleaning roller 9 and the cleaning blade 10.
It is a structure in which the charge is removed by using the charge removing lamp 11 and the charge is removed by the charge removing lamp 11.

Below the transfer belt 1, a transfer paper storage unit 1 is provided.
A sheet feeding roller 13 that sequentially pulls out the transfer sheets 7 stacked on the sheet 2 from the top, a separation unit 14 that separates the transfer sheets 7 from each other by preventing the double feeding of the transfer sheets 7, and the separated transfer sheets 1 The feeding unit 15 and the like that lead to Transfer belt 1
The transfer paper 7 separated from the transfer belt 1 is on the upper part of the
A paper discharge unit 17 for guiding the sheet to the fixing unit 16 is provided. The fixing unit 16 fixes the image transferred onto the transfer paper 7 by the transfer unit 8 and discharges the image onto the paper discharge tray 18.

In this embodiment, the wet developing unit 6 is used. That is, the developing unit 6 includes a developing roller 20 that supplies toner to the photosensitive drum 3, a reverse roller 21 that uniformizes the film thickness of the toner on the photosensitive drum 3, and a photosensitive drum, in a container 19 that stores the toner together with a solution. Three
It has a rotating member such as an electric field roller 22 for aggregating the above toner.

2 and 3 show a supporting structure and a driving structure of the photosensitive drum 3. In the figure, reference numeral 23 denotes a side plate disposed on the back side of the main body (not shown) of the image forming apparatus P. A front side plate (not shown) is disposed in front of the side plate 23 (on the left side in FIG. 2) so as to face the side plate 23 with a predetermined gap. Therefore, the space on the left side of the illustrated side plate 23 is the internal space 24 of the apparatus main body, and the space on the right side is the external space 25 that is outside the rear surface of the apparatus main body. A drive unit 2 for driving the photosensitive drum 3 is provided in this external space.
6 is provided.

This drive unit 26 is a drive system support 2
7, a motor 28 as a drive source attached to the drive system support 27, and a shaft support member 29. The drive system support 27 is a base 30 attached to the side plate 23.
A bracket 31 for mounting the motor 28, and a plurality of studs 32 for connecting the base 30 and the bracket 31.
And consists of. The shaft support member 29 has a flange 33 at one end that is fixed to the outer surface of the base 30.
3 is defined as a cylindrical shape having a large-diameter portion 34 close to 3 on its outer peripheral portion, and bearings 36 rotatably supporting the vicinity of the rear end of a drum shaft 35 as a rotating shaft are provided at both ends at predetermined intervals. It is installed. A drive-side coupling member 38 is fixedly fitted to the tip of a motor shaft 37 that is directly connected to the motor 28 and serves as a drive shaft.
A driven side coupling member 39 is fixedly fitted to the rear end. In this case, the movement of the drum shaft 35 in the axial direction is restricted by the contact between the fixed nut 40 screwed on the drum shaft 35 and the flange 33 of the shaft support member 29. In addition, the side plate 23 of the apparatus main body has a large diameter portion 3 of the shaft support portion village 29.
A positioning fitting portion (hole) 41 for supporting the 4 in a fitted state is formed. As shown in FIG. 3, the drive unit 26 is an independent assembly structure separated from the side plate 23. The shaft support member 29 is fitted to the positioning fitting portion 41, and the base 3
0 is attached to the attachment portion (not shown) of the side plate 23 from the back side of the side plate 23.

When assembling the drive unit 26, as shown in FIG. 4, the holes 30 formed in the base 30 are used.
The large-diameter portion 34 of the shaft support member 29 is fitted to a to join them together, and the motor bracket 31, the motor 28, and the stud 32 are assembled in advance, and the same diameter as the drum shaft 35 is provided at the end. A shaft-shaped jig J having a locking hole Ja is fitted into the bearing 36 of the shaft support member 29, and in this state the tip of the motor shaft 37 is fitted into the locking hole Ja of the jig J. After connecting the base 30 and the stud 32, the jig J is pulled out from the shaft support member 29. By doing so, the drive unit 26 can be assembled in a state in which the shaft center of the shaft support member 29 and the shaft center of the motor shaft 37 are positioned on the same shaft center.

The photosensitive drum 3 has flanges 3a fixedly fitted at both ends. A casing (not shown) having a pair of support plates (not shown) that rotatably supports both ends of the photosensitive drum 3 is provided on the inner space 24 side of the apparatus body so as to be drawn out. .
The flange 3a of the photoconductor drum 3 is fitted to the drum shaft 35 in a state of being slidable in the axial direction and being prevented from rotating in the rotational direction. Further, such a drive unit 26 is provided for each photosensitive drum 3.

As described above, in the structure of the present embodiment, the electrostatic latent image is formed and the electrostatic latent image is developed in the process of rotating the photosensitive drum 3 as described above. , The rotation of the motor 28 is sequentially transmitted to the motor shaft 37, the coupling members 38 and 39, the drum shaft 35, and the flange 3a to rotate. In this case, the position of the shaft center of the shaft support member 29 is determined by the positioning fitting portion 41 of the side plate 23, and the position of the shaft center of the drum shaft 35 is determined by the shaft support member 2.
9 and the flange 3a of the photosensitive drum 3 is fitted to the drum shaft 35, the photosensitive drum 3 can be rotated at an accurate position.

When the casing is pulled out from the main body of the apparatus for maintenance and inspection of the apparatus, the photosensitive drum 3 is opened on the front side of the main body of the apparatus. In this case, the drum shaft 35 remains on the apparatus main body side while being supported by the shaft support member 29. When exchanging the shaft support member 29, the drive unit 26 can be attached to and detached from the side plate 23 in a large work space on the back side of the apparatus body, so that workability can be improved.

Further, since the side plate 23 is formed with the positioning fitting portion 41 into which the shaft supporting member 29 is fitted, the positioning fitting portion 41 of the side plate 23 is fitted into the large diameter portion 3 of the shaft supporting member 29.
The rotational position of the drum shaft 35 in the main body of the apparatus can be accurately and easily determined only by fitting the four.

[Second Embodiment] Next, a second embodiment of the present invention will be described with reference to FIGS. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. As described above, the developing unit 6 has the developing roller 20, the reverse roller 21, and the electric field roller 22 as rotating members, respectively. The present embodiment is a specific example of the structure of the rotation transmission device 42 that transmits the rotation of the drive unit to the rollers 20 to 22.

FIG. 6 shows the drive structure of one photosensitive drum 3 and the developing section 6 corresponding to this photosensitive drum 3, and the axes of the developing roller 20, the reverse roller 21 and the electric field roller 22 are respectively shown. At the end, the developing roller gear 4
3, the reverse roller gear 44 and the electric field roller gear 45 are fixedly fitted. A developing bracket 47 is fixedly connected to the base 30 of each drive unit 26 via a plurality of studs 46. The developing roller gear 43, the reverse roller gear 44, and the electric field roller gear 45 are in mesh with intermediate gears 48, 49, and 50, respectively. A plurality of drive shafts 51, 52, 53 having these gears 48, 49, 50 fixed to one end are supported by the developing bracket 46 and the base 30 via bearings 54. The drive shaft 51 has a developing pulley 55 and an intermediate pulley 56.
Is fixedly fitted, an intermediate pulley 57 is fixedly fitted to the drive shaft 53, and a timing belt 58 is wound around the intermediate pulleys 56 and 57. A reverse pulley 59 is fixedly fitted to the drive shaft 52.

As described above, the developing pulley 55 of the rotation transmitting device 42 provided for each photosensitive drum 3 is connected to the developing motor 62 (see FIG. 6) which is a common driving unit via the timing belt 60 and the driving pulley 61. The reverse pulley 59 is connected via a timing belt 63 and a drive pulley 64 to a reverse roller motor 65 (see FIG. 6) which is a drive unit.

Further, a plurality of cleaning roller gears 66, which rotate integrally with the cleaning roller 9, respectively.
6 is connected to a cleaning roller pulley 68 via a gear train 67, and these cleaning roller pulleys 68 are connected to a cleaning motor 71 via a timing belt 69 and a drive pulley 70. The timing belts 60 and 69 are routed by a plurality of idler pulleys 72.

In FIG. 6, the control circuit 73 includes an operation unit 7
4 and is configured to control the operations of the developing motor 62, the reverse roller motor 65, and the cleaning motor 71.

In the above structure, when the developing motor 62 is driven, its rotation is transmitted to the developing pulley 55.
The drive shaft 51 is driven and the developing roller 20 rotates directly. Further, since the rotation of the drive shaft 51 is transmitted to the drive shaft 53 via the intermediate pulleys 56 and 57 and the timing belt 58, the electric field roller 22 rotates. Reverse roller motor 65
When is driven, its rotation is transmitted to the reverse pulley 59, so that the drive shaft 52 drives the reverse roller 21. When the cleaning motor 71 is driven, its rotation is transmitted to the cleaning roller pulley 68, so that each cleaning roller 9 rotates.

As described above, according to this embodiment, the drive system support 27 is provided with the rollers (rotating members) 20 to 22 of the developing section 6.
Since the rotation transmitting device 42 for transmitting the rotation from the motors (driving parts) 62 and 65 is mounted on the
Can be attached to and detached from the side plate 23 in a wide working space on the back side of the apparatus body.

The rotation transmission device 42 is also applied to the case where the rotation of the drive unit is transmitted to the rotary member (developing roller, replenishing roller, agitator, etc.) of the dry developing unit.

[Third Embodiment] Next, a third embodiment of the present invention will be described with reference to FIG. The same parts as those in the third embodiment are designated by the same reference numerals and the description thereof will be omitted. In this embodiment,
A joint portion 35 coaxially fitted to each other at the centers of the end surfaces of the drum shaft 35 directly connected to the motor 28 and the motor shaft 37.
a and 37a are formed, and a coupling member 75 that connects the drum shaft 35 and the motor shaft 37 with the fitting portions 35a and 37a fitted is provided. Therefore, the motor shaft 37 and the drum shaft 35 are coaxially connected to each other without aligning their axes.

[Embodiment 4] Next, an embodiment of the present invention according to claims 5 and 6 will be described with reference to FIGS. FIG. 8 is a schematic diagram for explaining the outline of the overall configuration of the image forming apparatus according to the present invention. The image forming apparatus 1 shown in FIG. 8 includes a transfer belt in which a plurality of image forming units (hereinafter, referred to as “process units”) 2 are arranged to electrostatically attract a transfer sheet as a transfer material. They are arranged along the extension direction of 3.

The process unit 2 includes the optical writing unit 4
Is a unit for executing a well-known electrophotographic image forming process, which is attached, and is an axial direction of a drum-shaped photoconductor (hereinafter, referred to as “photoconductor drum”) 5 which is an image carrier incorporated therein. The image forming apparatus 1 can be pulled out to the outside. Further, the drawn process unit 2 can also be inserted into the image forming apparatus 1 (hereinafter, the drawing and inserting operations are referred to as “insertion / removal”).

The developing device equipped in the process unit 2 is a liquid developer in which toner of a color having a complementary color relationship corresponding to a color obtained by color separation of an original is dispersed in a base liquid such as isoper. A wet developing device containing (hereinafter, referred to as “developing solution”) is used.

The image forming apparatus 1 includes a process unit 2
A structure for transferring the visible image formed by the method to a transfer paper is provided. Hereinafter, a configuration for conveying the transfer paper will be described together with its functions. The transfer paper is fed from a paper feeding unit 6 attached to the main body of the image forming apparatus 1 and can be moved toward a transfer conveyance path formed by each process unit 2 and the transfer belt 3. At the time of feeding, the lateral position corresponding to the width direction in the lateral registration unit 7 is adjusted.

The transfer paper whose lateral position has been adjusted passes through the leading edge registration sensor 8. When the transfer sheet passes through the registration sensor 8, the image forming process on the process unit 2 side is executed based on the timing, and the visible image is carried on the photosensitive drum 5.

When the transfer paper passes through the registration sensor 8, it is electrostatically attracted to the transfer belt 3 and, in that state, moves on the conveying path constituted by the process units 2 and the transfer belt 3. The transfer paper that is attracted to the transfer belt 3 and moves, faces the photoconductor drum 5 of each process unit 2, so that the visible image carried on the photoconductor drum 5 is sequentially electrostatically transferred. The transfer of the visible image to the transfer sheet is executed by a bias from a transfer roller 9 arranged on the back surface side of the transfer belt 3 at a position facing the photoconductor 2 of the process unit 2.

The transfer paper which has passed through each process unit 2 is separated from the transfer belt 3 by the separation charger 10 and is introduced into the fixing device 11 to fix the transferred image by heat and pressure. After fixing, the transfer paper is the transport unit 1
The transfer direction is switched to either the direction toward the sheet discharge tray 13 or the direction toward the double-sided unit 14 by the swingable switching guide plate 12 that is transported toward the sheet 2a and is disposed at the end position of the transport unit 12a. .

When the conveyance direction toward the duplex unit 14 is set by the switching guide plate 12, the transfer sheets are switched back and loaded in the duplex unit 14,
It is again fed toward the position of the registration sensor 8.

As shown in FIG. 9, the process unit 2 can be inserted into and removed from the main body of the image forming apparatus 1 in the axial direction of the photosensitive drum 5.

In FIG. 9, the process unit 2 includes a support member 15 having a process unit side plate 2a located at one end of the photosensitive drum 5 in the axial direction, which is provided in the main body of the apparatus.
It is designed to be supported by 16. The process unit side plate 2a is the photosensitive drum 5 in FIG.
In the axial direction of, the process unit 2 is arranged on the axial end side corresponding to the front side in the direction in which the process unit 2 is drawn out (the direction indicated by arrow Q in FIG. 9).

The supporting members 15 and 16 are provided on the receiving surface facing the process unit side plate 2a, and the process unit 2 is provided.
A closing portion is formed for inserting and removing the device, and the side plate 2a is attached to the process unit 2 by inserting it into contact with the process unit side plate 2a of the process unit 2 inserted in the main body of the apparatus.

The supporting members 15 and 16 and the process unit side plate 2a that abuts them are provided with a structure for positioning the process unit 2 at the inserted position. The structure is formed on the process unit side plate 2a. The positioning hole 2b and the pins 15a, 1 provided on the supporting members 15, 16 side facing the positioning hole 2b.
6a and. Note that FIG. 9 shows the pins fitted into the positioning holes 2b provided in the side plate 2a of the upper process unit 2.

The process unit 2 includes support members 15 and 1
When it is inserted into the opening formed by 6, the supporting member 15 is inserted into the positioning hole 2b of the process unit side plate 2a.
When the 16-side pins 15a and 16a are fitted, the pins are attached to the apparatus main body while being positioned.

In the process unit 2 shown in FIG. 9, guide rails 17 and 18 are arranged on the ceiling and bottom of the process unit 2 along the inserting / removing direction of the process unit 2. The guide rails 17 and 18 are provided at the same position in a plan view, of which the guide rail 17 located at the ceiling portion has a cross-sectional shape or a concave shape, and the guide rail 18 located at the bottom portion is located at the ceiling portion. Guide rail 1
It has a convex cross-sectional shape that can be fitted to the No. 7.

The guide rails 17 and 18 are used for the transfer belt 3
This is a guide portion when the process units 2 arranged in the extension direction are inserted into and removed from the support members 15 and 16. That is, as is clear from FIG. 9, the process unit 2 is
Since the photoconductor drum 5 has a positional relationship so that it can face the optical writing unit 4 (see FIG. 8), the side view has a step-like shape in a state of protruding upward. Therefore, the weight balance of the entire process unit 2 is not so good, the portion where the photoconductor drum 5 is arranged is easily tilted, and the postures of the support members 15 and 16 at the time of insertion and removal with respect to the openings become unstable. In the present embodiment, the guide rails 17, 1
It is possible to prevent the posture of the process unit 2 from becoming unstable due to the fitting of the eight members together, so that the smooth insertion / removal work can be performed.

FIG. 10 is an exploded perspective view showing the internal structure of the process unit 2, in which the process unit 2 has a unit housing 20 as a housing,
The unit housing 20 is provided with a photosensitive drum 5, a developing member 21, a developing tank 21, a driving member such as a stirring section that enters the developing tank 21, a driving unit 22 having the driving member attached, and cleaning of the photosensitive drum 5. It has a structure in which the devices 23 are respectively arranged.

The photosensitive drum 5 is rotatably supported by the process unit side plate 2a, and the developing tank 21 has a sub tank 2 for replenishing toner.
Either 4, 4'is provided so as to be connectable. The sub-tanks 24, 24 'are connected to the developing tanks 21 installed in the process units 2 respectively,
One of the toner supply paths is selected and installed in the developing tank 21 because the toner supply paths are different in length in order to shift the positions in the horizontal direction so as not to interfere with each other. The photosensitive drum 5 is attached to the process unit side plate 2a.
The configuration for supporting by will be described in detail later.

In the vicinity of the upper portion of the peripheral wall 26 of the developing tank 21, a liquid receiving groove 25, which is a feature of this embodiment, is provided. Hereinafter, the configuration relating to the liquid receiving groove 25 in FIG. 11 will be described. FIG. 11 is a schematic diagram for explaining the configuration of the liquid receiving groove 25, and in the figure, the liquid receiving groove 25 is shown.
Is provided near the upper end of the peripheral wall 26 of the unit housing 20. The liquid receiving groove 25 is formed by opening the bottom of a wall 27 surrounding the outer surface of the peripheral wall 26 integrally with the peripheral wall 26 and opening the upper surface thereof. In addition, in FIG. 11, the symbol L indicates a developing solution.

The liquid receiving groove 25 is formed over the entire circumference of the peripheral wall 26 and is also formed in the sub tanks 24 and 24 'connected to the developing tank 21 as shown in FIG. Can flow. Further, a part of the flow path for flowing the overflowed developing solution L communicates with the liquid leakage detection unit 28. In this embodiment, the width (x) of the liquid receiving groove 25 is set to 2 to 10 mm. This width dimension corresponds to a dimension capable of receiving the overflow amount when a part of it overflows in a state where the developer tank 21 is filled with a predetermined amount of the developer L.

The liquid leak detection unit 28 is for detecting that the amount of the developer L overflowing into the liquid receiving groove 25 has reached a certain amount or more, and when it is detected, a warning unit (not shown) is used. It is supposed to give an alarm. In this embodiment,
The developer L overflowing from the developing tank 21 detects the liquid leakage detection unit 28.
The flow path of the developer, which is constituted by the liquid receiving groove 25, is inclined toward the liquid leakage detection unit 28 so as to easily reach

As described above, in the image forming apparatus according to the present embodiment, the liquid surface of the developing solution L is wavy due to the vibration when the process unit 2 is inserted and removed, and overflows from the developing tank 21 when it passes over the peripheral wall 26 of the developing tank 21. The developer L that has come out is received by the liquid receiving groove 25. The developer L overflowing from the developing tank 21 flows in the liquid receiving groove 25 and a part of the developer L reaches the liquid leakage detection unit 28. When the liquid leakage detection unit 28 detects a predetermined amount or more of the developer L, an alarm is issued. As a result, the operator can know that the developer L has overflowed by an alarm using the liquid leakage detection unit 28, and can discharge the overflowed developer L to the outside.

According to the present embodiment, the developer L overflowing from the developing tank 21 can be prevented from leaking to the outside, so that the peripheral portion of the developing tank in the process unit 2 is prevented from being contaminated by the developing solution L. Can be prevented.

[Embodiment 5] Next, an embodiment of the invention according to claim 7 will be described with reference to FIG. 12
11 is a schematic diagram corresponding to FIG. 11 for explaining the present embodiment. In FIG. 11, the developing tank 21 in the process unit 2 is provided with a cover 29 capable of covering the upper surface thereof.

The cover 29 is constructed as a leg portion 29a in which an end portion of a region covering the upper surface of the developing tank 21 is bent downward, and the leg portion 29a is inserted into the liquid receiving groove 25. The leg portion 29a has gaps x1 and x2 between the peripheral wall 26 and the wall 27 of the developing tank 21, which form the liquid receiving groove 25, and the opposing surfaces thereof. Further, a gap y is formed between the liquid receiving groove 25 and the bottom inner surface.
In this way, the leg portion 29 a of the cover 29 has the liquid receiving groove 25.
Is positioned in a non-contact state from the inner surface and the bottom portion of the.

The reason for providing the above-mentioned gap is as follows. When the leg portion 29a is in contact with the inner surface and the bottom portion of the liquid receiving groove 25, the developer L overflowing from the phenomenon tank 21 adheres to the surface of the leg portion 29a by the capillary phenomenon.
Therefore, if the developer L is constantly in contact with the legs 29a, when the cover 29 is lifted, the developer L attached to the surface of the legs 29 drips and stains the periphery of the developing tank 21. Or, the adhered developer L may be dried and adhered to block the flow path of the overflowed developer L. In view of this, in the present embodiment, the above-mentioned gap is set to eliminate the adverse effects of the constant contact of the developing solution, and the overflowing developing solution L is dropped into the liquid receiving groove 25.

Of the above-mentioned gaps, the gaps in the horizontal direction indicated by the symbols x1 and x2 are about 1 to 3 mm, and the gap in the vertical direction indicated by the symbol y is about 2 to 10 mm. The size of this gap is 2 m when the plate thickness of the cover 29 is 2 m.
In this case, it is assumed that the developer L overflows from flowing into the liquid receiving groove 25, and the contact between the leg portion 29a and the developer L is prevented. Has become.

Also, the cover 29 is used for the developing tank 21.
The drive unit 22 located above the liquid surface of the developing device is provided with a supporting leg 29b whose lower end abuts, and the supporting unit 29b is fixed by the driving unit 22, so that the leg portion 29a is fixed to the liquid receiving groove. It is adapted to be positioned at a predetermined position within 25.

As described above, according to this embodiment, the developing tank 2
The developer L overflowing from No. 1 is guided into the liquid receiving groove 25 by hitting the leg portion 29 a of the cover 29. Thereby, the scattering of the developing solution to the peripheral portion of the developing tank 21 can be prevented more reliably.

[Embodiment 6] Next, an embodiment of the invention according to claim 8 will be described. FIG. 13 is a schematic diagram for explaining the characteristic part of the present embodiment. In FIG.
Photoconductor drum 5 built in the process unit 2
Is disposed closer to the transfer belt 3 than the developing tank 21 inside the process unit 2 so as to face the transfer belt 3.

A cleaning device 23 for performing a cleaning process on the photoconductor drum 5 after the image transfer onto the transfer sheet conveyed by the transfer belt 3 is completed.
(See FIG. 10) is provided so as to be accessible.

The cleaning device 23 includes a swing fulcrum shaft 30.
The support arm 31 and the cleaning member 32 are provided. As shown in FIG. 13, the swing fulcrum shaft 30 is positioned below the position where the rotary shaft 5a of the photosensitive drum 5 is arranged at a position opposite to the transfer belt 3 with the photosensitive drum 5 interposed therebetween. There is.

The support arm 31 is a member whose base end is positioned on the swing fulcrum shaft 30 and is swingably supported.
An extended portion reaching the swinging end is arranged on the side opposite to the peripheral surface of the photosensitive drum 5 facing the transfer belt 3. The cleaning member 32 is provided at the swing end of the support arm 31.

In FIG. 13, the cleaning device 23
Is capable of separating the cleaning member 32 from the peripheral surface of the photosensitive drum 5 by swinging the support arm 31 in the clockwise direction along the direction indicated by the arrow S0 with the swing fulcrum shaft 30 as a fulcrum. The cleaning member 32 can be brought into contact with the peripheral surface of the photosensitive drum 5 by swinging the support arm 31 counterclockwise about the swing fulcrum shaft 30.

The cleaning device 23 is not provided with the swinging fulcrum of the cleaning member 32 on the cleaning member 32 itself, but is provided outside the cleaning unit village 32. As a result, as shown in FIG.
When the cleaning member 32 is swung in the direction of separating from the photoconductor drum 5, the cleaning member 32 is separated from the photoconductor drum 5 at a time when the cleaning member 32 is provided with a swing fulcrum, as compared with the case where the cleaning member 32 itself is provided with a swing fulcrum. 32
Can be separated from the photoconductor drum 5 in a state in which the amount of inclination of is reduced. This prevents the collected developer from spilling due to the extreme inclination of the cleaning member 32 when the excess developer collected from the photoconductor drum 5 remains inside the cleaning member 32. It

When the cleaning device 23 is separated from the photosensitive drum 5, the photosensitive drum 5 can be inserted and removed from the side of the process unit 2 facing the transfer belt 3 as shown by an arrow W. . Since there is only an opening for exposing the photoconductor drum 5 on the side of the process unit 2 that faces the transfer belt 3, there is no interfering substance when the photoconductor drum 5 is inserted and removed, and the insertion and removal operation is performed. Can be done easily.

[Embodiment 7] Next, an embodiment of the invention according to claim 9 will be described. FIG. 15 is a schematic diagram for explaining the features of this embodiment. In FIG.
In the same manner as the conventional configuration shown in FIG. 1, the peripheral wall portion of the photosensitive drum 5 is attached to the drive shaft for the photoconductor drum which is previously attached to the apparatus main body side and the flange for the photoconductor attached to the drive shaft. The case where the other of the flanges for the photosensitive drum is mounted is shown.

In FIG. 15, the slide guide 4 is provided on the process unit side plate 2a of the process unit 2.
A support hole 41 for fitting 0 is formed. The slide guide 40 has the process unit side plate 2 on the outer peripheral surface.
It is composed of a cylindrical member having a flange portion 40a that is fastened to a. A bearing 47 is loaded inside the slide guide 40, and a spring holding member 44 for inserting one end in the longitudinal direction of a biasing spring 43 arranged between the bearing 47 and the flange 42 is fitted into the bearing 47. ing. The urging spring 43 has one end in the longitudinal direction loaded inside the spring holding recess 44a formed on the end surface of the spring holding member 44 that faces the flange 42 in the axial direction.
The boss portion formed on the surface of the flange 42 opposite to the surface facing the peripheral wall portion of the photosensitive drum 5 is loaded with the other end in the longitudinal direction.

The spring holding member 44 is provided with a drive shaft insertion hole 44b penetrating along the axial direction, and a nut member 45 is integrated on the opposite side of the spring holding recess 44a corresponding to one axial end. ing. As a result, the spring holding member 44 and the nut member 45 through which the drive shaft 46 is inserted are
The center position is aligned via the slide guide 40.

The nut member 45 is formed with a female screw portion concentric with the drive shaft insertion hole 44b formed in the spring holding member 44, and the female screw portion is formed at the shaft end of the drive shaft 46. It is possible to screw in the male screw part.

As described above, in the structure of the present embodiment, when the process unit 2 is incorporated in the apparatus main body, the flange located on the process unit side plate 2a side with reference to the drive shaft 46 previously located on the apparatus main body side. Assemble 42. When the flange 42 is inserted into the drive shaft 46, the flange 42 is located at the shaft end of the slide guide 40 attached to the process unit side plate 2a, and is opposed to the position of the drive shaft 46 together with the process unit side plate 2a.

As shown in FIG. 16, when the drive shaft 46 is inserted into the flange 42, the process unit 2 is pushed into the leg of the drive shaft 46 so that the drive shaft 46 is biased by the spring 43.
The shaft end can be inserted into the drive shaft insertion hole 44b provided in the spring holding member 44 by passing through the inside.

The shaft end has the drive shaft insertion hole 4 of the spring holding member 44.
In the state in which it is inserted into 4b, as shown in FIG. 17, the nut member 45 is rotated and screwed into the male screw portion having the female screw portion at the shaft end of the drive shaft 46. When the female threaded portion of the nut member 45 is screwed into the male threaded portion of the drive shaft 46, the nut member 45 advances along the axial direction of the drive shaft 46, which is in a stationary state in the axial direction. The bearing 47 that is rotating can be moved in the same direction in the slide guide 40.

The forward movement of the nut member 45 is continued until the male screw portion of the drive shaft 46 is completely screwed into the female screw portion, and the end of the male screw portion of the drive shaft 46 hits the nut member 45. The progress is over. This state is shown in FIG. 18, and in FIG. 18, when the male screw portion of the drive shaft 46 is completely screwed into the female screw portion of the nut member 45, the elastic force accumulated when the nut portion village 45 advances. The flange 42 is moved to the photosensitive drum 5 by the urging force of the urging spring 43.
Press against the end face of the peripheral wall.

As described above, according to this embodiment, by pushing the process unit side plate 2a against the drive shaft 46,
The slide guide 40 attached to the side plate 2a
The drive shaft 46 is ready to be supported by the process unit side plate 2a simply by inserting the drive shaft 46 therein.

[Embodiment 8] Next, claims 10 to 13
An embodiment in which the invention according to is applied to an electrophotographic printer will be described. 22A is a front view showing a schematic configuration of a main part inside the printer according to the present embodiment, and FIG. 22B is an external perspective view of the copying machine. FIG. 22
In (a), a charging roller 2 as a charging unit, a developing unit 3, and a transfer unit that control an image formation around a photosensitive drum (hereinafter, referred to as “photosensitive member”) 1 as an image carrier that is a rotating member. The transfer roller 4, the cleaning device 5, the static eliminator 6 and the like are arranged. Of these, the charging roller 2, the developing device 3, the cleaning device 5, and the static eliminator 6 are housed in a common case 7 and integrated as an image forming unit (image forming unit) 13. A paper feed cassette 8 is arranged below the photoconductor 1, and a fixing roller pair 9 and a paper discharge tray 10 are arranged above the photoconductor 1.
In this printer, a toner image is formed on the photoconductor 1 by a well-known electrophotographic process, and this toner image is transferred by a transfer roller 4 onto a transfer paper as a transfer material sent from a paper feed cassette 8. . Then, when the transfer sheet onto which the toner image has been transferred passes through the fixing roller pair 9, the toner image is fixed and then discharged to the discharge tray 10.

The case 7 of the image forming unit 13 is slid in the axial direction of the photoconductor 1 with respect to the main body of the apparatus.
Slide guide 1 so that it can be pulled out and inserted
1 and 12 are attached. FIG. 22B shows a state in which the front cover 15 of the apparatus main body 14 is opened and the image forming unit 13 is pulled out. In the illustrated example, a two-stage rail-shaped slide guide 12 that is slidable with respect to the slide guide fixed to the apparatus main body side is used. The two-stage slide guides 12 can be contracted. From the front surface of the case of the image forming unit 13, an operation knob 16 as an operation member used for releasing or re-fixing the device main body 14 side at the time of pulling out / inserting is projected.

Further, arms 18 are rotatably attached to the image forming unit 13 by a support shaft 17 on the rear side and the front side in the unit inserting direction, respectively.
As shown in (a) and (b), the photoconductor 1 can be swung so as to move toward and away from the photoconductor 1. The arm 18 is provided with a component of the image forming unit 13 which becomes a hindrance when the photoconductor 1 is taken out upward, as will be described later, for example,
Only the cleaning device 5 or a portion including the cleaning device 5, the static eliminator 6, and the charging roller 2 is supported. As shown in FIG. 24B, this arm can be fixed to the case 7 of the image forming unit 13 with parts such as screws and pins when it is kept in the most separated state from the photoconductor 1. .

The image forming unit 13 is inserted into the positioning hole 20a formed in the front side plate 19 of the apparatus body 14 in order to perform positioning with the apparatus body side when the image forming unit 13 is completely inserted in the apparatus body 14. A positioning hole 21b into which the positioning pin 21a and, conversely, the positioning pin 20b provided on the front side plate 19 enter is provided.

The printer of this embodiment has the following structure in order to reduce the replacement portion of the photoconductor 1 and to pull out the image forming unit 13 from the apparatus body 14 to improve the operability of the photoconductor 1. Has been adopted.

FIG. 23 (a) is an explanatory view showing a state where the image forming unit 13 is set in the apparatus main body, FIG. 23 (b) is an explanatory view showing a state where the unit 13 is pulled out halfway, and FIG. 4] is an explanatory view of a state where the unit 13 is completely pulled out. Photoconductor 1 in the printer of the present embodiment
Is in the shape of a sleeve in which a photosensitive layer is formed on a hollow cylindrical conductive substrate whose both end wall portions are open. In order to hold the photoconductor 1 in the main body of the apparatus, front and rear flanges 3 that engage with openings of the photoconductor 1 on the back side and the front side of the apparatus, respectively.
0 and 31 are provided. Of these, the rear flange 31
Is used as a holding member for holding the back side of the photoconductor 1, and is fixed to a drive rotating shaft 32 extending from the rear side plate 14a of the apparatus main body to the front and rear side plates of the main body. Further, the front flange 30 is attached to the drive rotary shaft 32 extending through the photosensitive member 1 so as to be movable in the thrust direction. In the illustrated example, the two flanges 30 and 31 and the opening of the photoconductor 1 are favorably positioned in the thrust direction.
Tapers are formed on both openings and both flanges.

The front flange 30 is provided on the drive rotary shaft 32 and in front of the front flange 30.
Spring 33 and spring retainer 3 for biasing side
4 is mounted so as to be movable in the thrust direction. Both ends of this spring 33 are locked to the front flange 30 and the spring receiver 34, respectively, and the three are connected. A ball bearing 35 is fixed to the outer circumference of the spring receiver 34 by press fitting, and the above-mentioned operation knob 16 is rotatably attached by engagement by annular unevenness. The operation knob 16 has a hollow portion into which the tip of the drive rotary shaft 32 can enter, and is screwed into a screw portion (hereinafter referred to as "tip screw portion") formed on the inner peripheral surface of the tip of the central shaft. A threaded portion (hereinafter, referred to as “knob threaded portion”) is formed. A spring receiver 34 and a bearing receiver 36 for guiding the thrust movement of the ball bearing 35 are attached to the front plate portion of the case 7 of the image forming unit so as to cover the ball bearing 35.

On the other hand, projections 22 and 23 are formed on the inner surface of the bottom wall of the case 7 at positions corresponding to the front and rear ends of the photoconductor 1. Of these, the rear projection 23 includes a rear facing surface portion 23a as an engaging portion facing the opening end surface 1a of the photoconductor 1 from the rear side of the apparatus main body, and a lower facing surface portion facing the peripheral surface of the photoconductor 1. 23b is formed. Also, the front protrusion 2
2, a rear facing surface portion 22a facing the opening end surface 1a of the photosensitive member 1 from the front side of the apparatus and a lower facing surface portion 22b facing the peripheral surface of the photosensitive member 1 are formed. The front and rear facing surface portions 22a and 23a of the protrusions 22 and 23 are engaged with the photoconductor 1 from the front and rear direction when the image forming unit 13 is inserted or pulled out. In addition, the lower facing surface portions 22b and 23b function as a receiving portion that supports the photoreceptor 1 whose holding by the front and rear flanges 30 and 31 has been released. The height and the like of both surface portions are set so as not to come into contact with the front and rear flanges 30 and 31 and the photoconductor 1 when the image forming unit 13 is mounted on the main body.

In the main body set state of the image forming unit 13 shown in FIG. 23 (a), the operation knob 16 is screwed into the tip screw portion of the drive rotary shaft 32 and the knob screw portion of the operation knob 16, and the spring 33 is attached to the front flange 30. To the back of the device. By this biasing force, the front flange 30 is brought into close contact with the front opening of the photoconductor 1, and the photoconductor 1 is biased toward the rear side of the apparatus to bring the back opening of the photoconductor 1 into close contact with the rear flange 31. When the drive rotating shaft 32 rotates for the image forming operation, the photosensitive member 1 rotates due to the tapering between the fixed rear flange 31 and the photosensitive member 1. Along with this, the front flange 30 that comes into close contact with the photoconductor 1 also rotates, and the spring receiver 34 and the operation knob 1 that are connected to the front flange 30 through a spring 33 or the like.
6 also rotates, and the rotation of the front side of these rotary drive shafts 32 is
It is received by the bearing receiver 36 via the ball bearing 35 on the spring receiver 34.

When the image forming unit 13 is pulled out, first, the operation knob 16 is rotated to remove it from the threaded end portion of the drive rotary shaft 32. During this time, the front flange 30, the spring 33,
Spring receiver 34, ball bearing 35, operation knob 1
6 moves together in the bearing receiver 36 toward the front side (right side in the drawing) of the apparatus. At this time, although the spring 33 is somewhat elongated, the front flange 30 connected to the spring 33 is separated from the front opening of the photoconductor 1. Then, the front side of the photoconductor 1 hangs downward due to its own weight and rests on the lower facing surface portion 22b of the front protrusion 22.

Then, as shown in FIG. 22B, the image forming unit 13 connected to the apparatus main body through the slide guides 11 and 12 is pulled out. In the middle of this drawer,
The rear facing surface 23a of the rear projection 23 of the case 7 abuts against the end surface 1a of the photoconductor 1 and pushes the photoconductor 1 forward.
As a result, the opening on the rear side of the photoconductor is separated from the rear flange 31, and the photoconductor 1 is pulled out together with the case 7. Further, the rear side of the photoconductor 1 which is disengaged from the rear flange 31 hangs downward due to its own weight, and the lower facing surface portion 2 of the rear projection 23.
Go on 3b. In the state of FIG. 23B, the holding of the photoconductor 1 via the front and rear flanges 30 and 31 is released as described above, and the front and rear protrusions 22 and 23 have the lower facing surface portions 22b and 2b.
It is in a state of being held on 3b.

FIG. 25 (a) schematically shows the relationship between the case 7 and the photoconductor 1 during the above-mentioned drawer. As shown in this figure, the photosensitive member 1 is held on the front and rear projections 22 and 23 while being pushed by the rear facing surface portion 23a of the rear projection 23 while being, so to speak, caught by the rear projection 23. It is pulled out together with Case 7.

In the state shown in FIG. 23 (c) where the drawing is completed, the rotary drive shaft 32 is completely removed from the inside of the photosensitive member 1. As a result, as shown in FIG. 24 (b), the arm 18 holding the components of the image forming unit 13 located above the photoconductor 1 is swung to open the upper part, so that the photoconductor 1 is easily moved upward. Can be taken out. And
It is possible to easily inspect and clean the inside of the developing device 3 which has been hidden by the photoconductor 1 and set a new photoconductor 1. As shown in this figure, since the front flange 30 is connected to the spring receiver 34 via the spring 33, even if the front flange 30 is disengaged from the drive rotary shaft 32, it does not fall downward alone.

On the contrary, when inserting the image forming unit 13, the procedure opposite to that of FIGS. 23 (a) to 23 (c) is performed, and finally the operation knob 16 is rotated to be attached to the tip screw portion of the rotary drive shaft 32. . Of these, FIG. 25B schematically shows the relationship between the photoconductor 1 and the case 7 during the inserting operation. The front facing surface portion 22a of the front protrusion 22 pushes the end surface of the opening of the photoconductor 1 and, so to speak, the front protrusion 22 moves the photoconductor 1 together with the case 7 so that the photoconductor 1 is hooked. Immediately before the completion of the insertion due to this movement, the taper portion of the rear flange 31 and the taper portion of the back side opening of the photoconductor 1 engage with each other to raise the back side of the photoconductor 1. And the last operation knob 1
6 by rotating the front flange 30 to the photosensitive member 1
It is made to enter into the front side opening part along the taper part, and both are closely contacted.

As described above, when the image forming unit 13 is pulled out or inserted, the front and rear projections 22 and 23 of the photoconductor 1 are inserted.
The front and rear facing surface portions 22a and 23 of the photosensitive member 1 hook the opening end surface of the photosensitive member 1. However, if the size of the hooking is small, the end of the photosensitive member 1 may be impacted by a drop on the lower facing surface portions 22b and 23b of the photosensitive member 1. May raise the front and rear projections 22 and 23. If you climb up like this,
The photoreceptor 1 cannot be pulled out or inserted together with the image forming unit 13. In the example of FIG. 22, when the cleaning blade of the cleaning device 5 continues to apply pressure to the photoconductor 1 even when the image forming unit is pulled out, the photoconductor 1
Such a problem can be prevented because the pressing force from above can be exerted, but the above problem may occur in the case of an apparatus configuration in which no pressure is applied by the cleaning blade or the like.

In order to prevent such a problem, the lower facing surface portions 22b and 23b of the image forming unit case 7 will be described below.
A configuration example of a pressing mechanism as a pressing unit that presses the peripheral surface of the photosensitive member 1 against each other will be described. FIG. 26
In the configuration example of (a), in order to ensure that the front and rear protrusions 22 and 23 (only the rear protrusion 23 is shown) and the photosensitive member 1 are caught, a bifurcated support urged downward by a spring 50. The upper portion of the photoconductor 1 is pressed downward by using a pair of rollers 51 attached to a member. The configuration example of FIG. 26B shows a pair of portions 42, 42 corresponding to the above-mentioned protrusions.
The bifurcated member 41 formed with is pressed upward by the spring 40.

26 (a) and 26 (b), when the image forming unit 13 is set in the apparatus main body to form an image, the relationship between the front and rear projections 22 and 23 and the photoconductor 1 and the like is large. It is desirable to cancel the relationship in order to prevent the deterioration of the surface of the photoconductor and the constituent members of the projection. In this way, a configuration for making the pressing force released at the time of the setting will be described with reference to the configuration example of FIG. 26 (b). To release this, for example, as shown in FIG. 26B, a hole 43 is formed in the bifurcated member 41, and as shown in FIG. A regulation member 44 for regulating the above is provided.

Further, such a restricting member 44 is interlocked with the drawing or inserting operation of the image forming unit 13,
It is desirable to provide an interlocking mechanism as an interlocking switching means for moving between the regulation position that has entered the hole 43 and the retracted position that has exited from the hole 43. In the configuration example of the interlocking mechanism of FIG. 27, the above-mentioned movement is performed by interlocking with the attachment and removal of the operation knob 16 with respect to the drive rotary shaft 32. That is, in this example, the flange portion 60 is formed on the spring receiver 34, and the flange portion 60 is formed.
The holding member 4a is formed at the rear end so as to face the front and back surfaces in a relationship of sandwiching from the thickness direction, and the forward / backward movement member 4 moves forward / backward so that the front end can enter or retract into the hole 43.
4 is provided. In the illustrated example, a hole 22c for penetration is formed in the front protrusion 22 in order to allow the advancing / retreating member 44 to pass through.

The advancing / retreating member 44, when the operation knob 16 is attached to the drive rotary shaft 32, is connected to the operation knob 16 in the thrust direction.
Since 4 is located at the farthest side of the device, it is located at the farthest position of the device with the sandwiching portion 44a being pushed toward the far side of the device by the flange portion 60 of the spring receiver 34, as shown in FIG. 28 (a). Thus, the tip of the forked member 41 is located in the hole 43 and the bifurcated member 41 is positioned at the retracted position. On the other hand, when the operation knob 16 is detached from the drive rotary shaft 32, the pinch portion 44a is moved to the flange portion 60 along with the movement of the spring receiver 34 integrated with the operation knob 16 toward the front side of the apparatus at the time of detachment. It moves while being pushed to the front side of the device, and
As shown in (b), the tip thereof comes out of the hole 43. Then, when the removal of the operation knob 16 is completed, the tip of the operation knob 16 completely comes out of the hole 43. As a result, the restriction on the bifurcated member 41 is completely released, and the member 41 is pushed up by the spring 40 and comes into contact with the photoconductor 1. In the example of FIG. 28, the tip end of the advancing / retreating member 44 and the inner surface of the hole 43 are formed with a taper for smooth engagement and disengagement of the both.

The interlocking mechanism shown in FIGS. 27 and 28 can also be used as a pressing mechanism for pressing the photosensitive member 1 downward as shown in FIG. 26 (a). Also, the operation knob 1
6 and the forward / backward movement member (regulation member) 44 for such pressure regulation
The interlocking mechanism with and can be variously modified. Further, in the above-described interlocking mechanism, only the portion corresponding to the protrusion on the back side of the device is provided with the pressing function or the pressing regulation is performed, but the same modification may be added to the protrusion 22 on the front side of the device.

FIGS. 29 (a) and 29 (b) show another structural example of the interlocking mechanism for preventing the above-mentioned problems. FIG. 29 (a) is its rear view and FIG. 29 (b) is its view. It is a side view.
In this example, a plate-like member 41 having a portion 42 corresponding to the rear facing surface portion 23a of the rear projection 23 is pressed upward by a spring 40, and a pair of rollers 45 are attached at positions sandwiching the corresponding portion 42. ing. The roller 45 functions as the lower facing surface portion 23b of the rear projection 23. A hole 43 is also formed in the plate-shaped member 41, and the advancing / retreating member 44 can be moved into or out of the hole 43. Such a plate-shaped member or the like can be used instead of the front protrusion 22. further,
It can also be used to press the photoconductor 1 from above and move the end of the photoconductor by hooking it as shown in FIG.

In the above embodiment, the image forming unit 1
Although the guide rails 11 and 12 are attached to the case 7 of 3, the guide rails 11 and 12 and the case 7 of the image forming unit 13 may be configured to be separable. For example, a case mounting table is attached to the guide rails 11 and 12, the case 7 of the image forming unit 13 is mounted on the mounting table, and the positioning mechanism appropriately positions the case. According to this configuration, the case 7 of the image forming unit 13 is removed from the guide rails 11 and 12 in a state where the image forming unit 13 is slid out and drawn out.
The whole 3 can be easily replaced with a new image forming unit.

As described above, in the printer of this embodiment,
Since the protrusions arranged on the end surface of the photoconductor 1 at positions where they do not collide with the flange of the photoconductor 1 are caught, the photoconductor 1 can be pulled out and inserted together with the image forming unit 13 into the main body of the apparatus. When dealing with a trouble of a certain image forming unit 13, it can be easily pulled out and inserted into the main body. In addition, from the image forming unit 13 pulled out from the main body,
Since the photoconductor 1 can be easily removed, it is easy to clean the parts other than the photoconductor 1 and troubles can be dealt with, and downtime for the troubles can be shortened.

The image forming unit 1 pulled out from the main body
3 can be cleaned without being moved to another place, while being pulled out and supported by the guide rails, so the floor area for cleaning and other work can be reduced and total printer installation can be performed. The area can be reduced.

When the photosensitive member 1 is pulled out or inserted into the main body together with the image forming unit 13, the lower facing surface portions 22b and 23b of the case 7 holding the photosensitive member 1 and the photosensitive member 1 are held.
If a pressing mechanism that presses the peripheral surface of the photosensitive member 1 against each other is provided, the photosensitive member 1 and the front-rear facing surface portions 22a and 23a are reliably caught, and the photosensitive member 1 is pulled out or inserted into the main body together with the image forming unit 13. It is possible to prevent troubles at the time.

In addition, the pressing of the pressing mechanism is performed by the operation knob 1
By interlocking with the attachment and detachment of 6 and restricting or releasing the restriction, unnecessary friction between the photoconductor 1 and the pressing portion of the pressing mechanism can be automatically avoided, and the service life of the parts can be extended. Besides, it is possible to prevent troubles when the photoreceptor 1 is pulled out or inserted into the main body together with the image forming unit 13.

[0132]

According to the invention of claims 1 to 4, a drive unit having a shaft supporting member for rotatably supporting a rotary shaft that rotates integrally with a rotating body mounted in the main body of the apparatus is provided in the main body of the apparatus. Since the side plate fixed to the back side can be attached to the side plate, the position of the axis of the rotary shaft can be determined by the shaft support member. Moreover,
When exchanging the shaft support member, the drive unit having the shaft support member can be removed from the side plate on the rear side of the apparatus main body and brought into a large work space, so that the shaft support member can be easily supported in the large work space. It is possible to perform the replacement work of the members.

In particular, according to the invention of claim 2, when the rotation transmission device for transmitting the rotation from the drive source to the rotating member which is rotationally driven in the device body is replaced, the drive unit provided with the rotation transmission device. Can be removed from the side plate on the back side of the apparatus body and brought to a large work space, so that the rotation transmission device can be easily replaced in a large work space.

Further, in particular, according to the invention of claim 3, when the drive unit is mounted on the apparatus main body, the shaft support member can be fitted to the positioning fitting portion formed on the side plate. The rotational position of the rotating body in the device body can be accurately and easily determined.

Further, according to the invention of claim 4, when the drive unit is mounted on the apparatus main body, the drive shaft directly connected to the drive source and the rotary shaft are formed at opposite shaft end portions. Since the drive shaft and the rotary shaft can be connected by the coupling member in a state where the fitting portions are coaxially fitted to each other, the drive shaft and the rotary shaft are not aligned with each other. It is possible to connect in a rotationally transmittable state without aligning.

According to the fifth to seventh aspects of the invention, the liquid developer which is about to overflow from the opening of the upper surface of the image forming unit where the liquid developer of the image forming unit is exposed to the outside is supplied to the peripheral wall of the housing portion of the image forming unit. Since it can be received by the liquid receiving groove formed in the above, it is possible to prevent the peripheral portion from being contaminated by the developer overflowing from the image forming unit.

In particular, according to the invention of claim 6, since the liquid developer received by the liquid receiving groove can be guided to the liquid leak detecting portion, the overflow of the liquid developer is notified to the operator and the liquid is detected. It becomes possible to promote the discharge of the developer.

Further, in particular, according to the invention of claim 7, the end portion of the cover which covers the upper surface of the image forming unit is made to enter the liquid receiving groove, and is not in contact with the inner surface and the bottom portion of the liquid receiving groove. By positioning the cover so that
The adhesion of the liquid developer to the end portion of the cover is reduced, and the liquid developer overflowing in the image forming unit is introduced into the liquid receiving groove without scattering to the outside, so that the peripheral portion is not polluted. It is possible to surely prevent it.

According to the eighth aspect of the present invention, there is provided a cleaning device which is positioned on the opposite side of the image transfer portion with the image carrier and below the position of the rotary shaft of the image carrier. Since the swing fulcrum shaft is provided, and further, the extension from the swing fulcrum shaft to the swing end is provided on the side opposite to the surface of the image carrier facing the image transfer portion, the support arm is provided. In the above, the portion where there is no member that interferes with the cleaning device can be used as the insertion / removal path of the image bearing member, which facilitates the insertion / removal operation.

According to the invention of claim 9, when the image forming unit is mounted with the drive shaft of the image carrier attached to the apparatus main body as a reference, the drive shaft is inserted in the unit side. Since the slide guide, the nut member and the drive shaft are arranged on the concentric line so that the nut member to be fastened can be aligned, the fastening position of the nut member and the drive shaft can be set simply by inserting the drive shaft into the slide guide. It becomes possible to correspond with. As a result, it is not necessary to align the nut member and the drive member one by one, and the mounting operability of the image forming unit can be improved.

According to the tenth to thirteenth aspects of the invention, as at least one rotating body accommodated in the unit that can be pulled out and inserted into the main body of the image forming apparatus, at least the end wall portion on the back side in the unit insertion direction is opened. Since the hollow cylindrical body is used, it is possible to reduce the cost of the hollow cylindrical body which is a replacement part. Moreover, when the unit is pulled out from the apparatus main body, the engaging portion provided on the unit is
Since the hollow cylindrical body can be moved together with the unit that is engaged with the hollow cylindrical body from the rear side in the unit insertion direction and is pulled out in this engaged state, the movement of the hollow cylindrical body causes the apparatus main body side to move. The hollow cylindrical body can be separated from the holding member provided on the opening side of the rotating body by the engagement with the portion of the opening, and the two can be separated. That is, by pulling out the unit from the main body of the apparatus, the both are automatically separated. Therefore, the labor for this separation is small.

In particular, according to the invention of claim 11, since the engaging portion does not come into contact with the rotating body when the unit is attached to the apparatus main body, wear of the rotating body and the engaging portion due to the contact. Can be prevented.

According to the twelfth aspect of the invention, since the engaging portion is configured with a simple structure of the facing member facing the opening end face on the back side in the unit insertion direction, the cost of the device is increased and the size is increased. Can be avoided. Moreover, when the unit is pulled out from the apparatus body, the holding member is retained by continuing the pulling out of the unit while the facing member is engaged with the hollow cylindrical body from the back side in the unit insertion direction. Since the peripheral surface of the end portion of the hollow cylindrical body which has been released and dropped and the receiving portion provided in the unit to receive this are pressed against each other by the pressing means, the end portion of the hollow cylindrical body which collides with the receiving portion due to the drop. Vibration can be suppressed. Therefore, it is possible to prevent the end portion of the hollow cylindrical body from being relatively large, for example, floating up to the extent that the engagement with the facing member is disengaged due to the vibration. Therefore, it is possible to favorably maintain the engagement of both of the units during the withdrawal from the apparatus body.

According to the thirteenth aspect of the invention, when the apparatus main body of the unit is set, the pressing means is made to release the pressing, so that the hollow cylindrical body is rotationally driven in the set state. Also, it is possible to prevent the surfaces of both ends of the hollow cylindrical body from being worn and deteriorated due to friction between the peripheral surface of the hollow cylindrical body and the receiving portion. Moreover, since the unit is switched to the pressed state from the released state of the pressing in conjunction with the operation of the operation member that needs to be performed before the unit is pulled out from the apparatus body, without performing an operation for special switching, It is possible to perform the switching to the pressed state necessary for preventing the trouble that occurs during the drawing.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an internal structure of an image forming apparatus according to a first embodiment.

FIG. 2 is a vertical sectional side view showing a drive unit in the image forming apparatus.

FIG. 3 is a vertical cross-sectional side view showing a relationship between a positioning fitting portion formed on a side plate and a shaft support member of a drive conit.

FIG. 4 is a vertical sectional side view showing a process of assembling a drive unit using a jig.

FIG. 5 is a vertical sectional side view showing a drive unit and a rotation transmission device according to a second embodiment.

FIG. 6 is an explanatory view showing a state in which a rotation transmission device is arranged for each photosensitive drum.

FIG. 7 is a vertical sectional side view showing a drive unit according to a third embodiment.

FIG. 8 is a schematic configuration diagram showing an internal structure of an image forming apparatus according to a fourth embodiment.

9 is a partial perspective view showing a state where the image forming unit shown in FIG. 8 is pulled out from the image forming apparatus.

10 is an exploded perspective view for explaining a configuration of an image forming unit used in the image forming apparatus shown in FIG.

11 is a sectional view of the image forming unit shown in FIG. 10 as viewed in the direction of the arrow P.

FIG. 12 is a schematic configuration diagram showing an internal structure of an image forming apparatus according to a fifth embodiment.

FIG. 13 is a schematic diagram for explaining the configuration of a cleaning device in the image forming apparatus according to the sixth embodiment.

14 is a schematic diagram for explaining the operation of the cleaning device shown in FIG.

FIG. 15 is a partial cross-sectional view illustrating a supporting structure of a photosensitive drum in an image forming apparatus according to a seventh exemplary embodiment.

16 is a partial cross-sectional view showing a step in the process of inserting the photosensitive drum in the support structure shown in FIG.

17 is a partial cross-sectional view showing another step of the process of inserting the photosensitive drum in the support structure shown in FIG.

FIG. 18 is a partial cross-sectional view showing a state when the photosensitive drum is completely inserted in the support structure shown in FIG.

FIG. 19 is a schematic diagram for explaining one of supporting structures of a cleaning device used in a conventional image forming unit.

20A is a schematic diagram for explaining the internal structure of the cleaning device shown in FIG. 19 in a normal state.
FIG. 6B is a schematic diagram for explaining the internal structure of the cleaning device in a swinging state. FIG. 6C is a schematic diagram for explaining the internal structure of the cleaning device having the swing structure according to the modification in the swing state.

FIG. 21 is a partial cross-sectional view illustrating a supporting structure of a photosensitive drum used in a conventional image forming unit.

FIG. 22A is a front view showing a schematic configuration of a main part inside a printer according to an eighth embodiment. (B) is an external perspective view of the printer.

FIG. 23A is an explanatory diagram showing a state where the process unit of the printer is set in the apparatus main body. (B) is explanatory drawing of the state which pulled out the same part. (C) is explanatory drawing of the state which pulled out the same unit completely.

24 (a) and 24 (b) are explanatory views of an arm of the unit.

FIG. 25A and FIG. 25B are explanatory views of a photosensitive member pull-out / insertion mechanism of the unit.

26 (a) and 26 (b) are explanatory views of the same drawer / insertion mechanism according to a modification.

27 is a schematic configuration diagram of the drawer / insertion mechanism of FIG. 26 (b).

28 (a) and 28 (b) are partially enlarged explanatory views of the drawer / insertion mechanism of FIG. 26 (b).

29 (a) and 29 (b) are explanatory views of the drawer / insertion mechanism according to another modification.

[Explanation of symbols]

[Description of Symbols in First, Second, and Third Embodiments] P Image forming apparatus 1 Transfer belt 2 Image forming unit 3 Photosensitive drum 3a Flange 4 of photosensitive drum 4 Charging unit 5 Latent image forming unit 6 Developing unit 7 Transfer paper 8 Transfer Section 16 fixing section 20-22 rotating member (developing roller, reverse roller,
Electric field roller) 23 Side plate 26 Drive unit 27 Drive system support 28 Motor 29 Shaft support member 35 Drum shaft 35a Fitting portion 37 Motor shaft 38, 39 Coupling member 41 Positioning fitting portion (hole) 42 Rotation transmission device 62, 65 Drive unit 75 Coupling member [Explanation of reference numerals in Embodiments 4, 5, 6 and 7] 1 Image forming apparatus 2 Process unit 2a Process unit side plate 3 Transfer belt 5 Photoreceptor drum 20 Unit housing 21 Developing tank 22 Drive unit 23 Cleaning Device 25 Liquid receiving groove 26 Peripheral wall 27 Liquid receiving groove wall 28 Liquid leak detection part 29 Cover 29a Leg part 29b Support leg 30 Swiveling fulcrum shaft 31 Support arm 32 Cleaning member 40 Slide guide 40a Flange part 41 Support hole 42 With flange 43 Bias spring 44 Spring holding member 44a Holding recess 44b Drive shaft insertion hole 45 Nut member 46 Drive shaft 47 of photoconductor drum Bearing [Explanation of reference numerals in Embodiment 8] 1 Photoconductor (rotating body) 1a End surface 2 Electrode roller 3 Developing device 4 Transfer roller 5 Cleaning device 6 Static eliminator 7 Case 13 Image forming unit 14 Device main body 14a Main body rear side plate 16 Operation knob 17 Support shaft 22 Front protrusion 22a Front facing surface portion 22b Lower facing surface portion 22c Penetration hole 23 Rear projection 23a Rear facing surface portion 23b Lower facing surface portion 30 Front flange 31 Rear flange 32 Drive rotary shaft 33 Spring 34 Spring bearing 35 Ball bearing 36 Bearing bearing 40 Spring 41 Bifurcated member 42 Projection portion 43 Hole 44 Advancement member (regulating member) 44a Clamping portion 45 Roller 60 Flange portion

   ─────────────────────────────────────────────────── ─── Continued front page    (31) Priority claim number Japanese Patent Application No. 8-108489 (32) Priority date April 3, 1996 (April 4, 1996) (33) Priority claiming country Japan (JP) (72) Inventor Masaki Hiroi             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Katsuaki Miyawaki             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Nobuhiko Umezawa             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Masami Hiramatsu             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh F term (reference) 2H035 CA07 CB03 CD01 CD05 CD07                       CD11 CD14 CD15 CG03                 2H074 AA03 BB02 BB42 BB64 BB68                       BB72 DD01 DD03 DD05 EE07                 2H134 GA01 GB03 HD01 HD08 KF02                       KF03 KF04 KF05 KG04 KG08                       KH12 KH16 KJ02 KJ03                 2H171 FA02 FA03 FA04 FA09 FA13                       FA17 GA12 GA13 GA29 JA14                       JA23 JA24 JA27 JA29 JA30                       JA31 JA32 JA34 JA39 JA45                       KA05 KA06 KA12 KA16 KA22                       KA23 KA25 KA29 LA03 LA13                       QA02 QA03 QA04 QA08 QB03                       QB15 QB32 QB40 QC03 QC05                       QC22 QC29 SA09 SA14 SA22                       SA26 WA08 WA10 WA23

Claims (13)

[Claims] 1. A drive unit having a shaft support member for rotatably supporting a rotary shaft that rotates integrally with a rotating body mounted in the main body of the apparatus, and a side plate fixed to the back side of the main body of the apparatus, An image forming apparatus comprising an attachment portion for detachably attaching the drive unit from the outside of the apparatus main body. 2. The image forming apparatus according to claim 1, further comprising a rotating member that is rotationally driven in the main body of the apparatus, separately from the rotating body, and transmits the rotation from the drive source to the driving unit to the driving unit. An image forming apparatus, comprising: 3. The image forming apparatus according to claim 1 or 2, wherein a positioning fitting portion for fitting the shaft support member is formed on the side plate. 4. The image forming apparatus according to claim 1, 2 or 3, wherein a drive source is provided in the drive unit, wherein drive shafts directly connected to the drive source and shaft ends of the rotary shaft facing each other are provided with each other. An image forming apparatus comprising: a coupling member that is coaxially fitted; and a coupling member that connects the drive shaft and the rotation shaft in a state where the fitting unit is fitted. . 5. A wet developing device for developing a latent image formed on an image bearing member with a liquid developer is mounted, and an opening for exposing a part of the liquid developer to the outside is provided on the upper surface, An image forming apparatus having an image forming unit detachable from the main body of the apparatus, wherein a liquid receiving groove is formed in a peripheral wall of a housing portion of the image forming unit. 6. The image forming apparatus according to claim 5, wherein the liquid receiving groove is communicated with a liquid leak detecting section. 7. The image forming apparatus according to claim 5, wherein a cover is provided to cover the upper surface of the image forming unit, and an end of a region covering the upper surface of the image forming unit enters the liquid receiving groove. In addition, the image forming apparatus is positioned such that the end portion is not in contact with the inner surface and the bottom portion of the liquid receiving groove. 8. A removable image carrier, and a cleaning device provided so as to be able to come into contact with and separate from the image carrier, and when the image carrier is attached and detached, the cleaning device carries the image carrier. In the image forming apparatus configured to be separated from the body, the cleaning device is placed below the position where the rotation shaft of the image carrier is arranged at a position opposite to the image transfer unit across the image carrier. A positioned swing fulcrum shaft and an outer surface that is swingably provided by the swing fulcrum shaft and that extends to a swing end to which a cleaning member is attached faces the image transfer portion of the image carrier. An image forming apparatus comprising: a supporting arm disposed opposite to the supporting arm. 9. An image forming apparatus comprising an image forming unit to which at least an image carrier is attached, which is detachably attached to the apparatus body, and a drive shaft of the image carrier previously attached to the apparatus body. A slide guide which is attached to the side plate of the image forming unit and into which the drive shaft can be inserted; and a nut member which is movably supported by the slide guide in the axial direction of the drive shaft and can be fastened to the drive shaft. An image forming apparatus comprising: the slide guide and the nut member, which are positioned on a concentric line with the axis of the drive shaft. 10. An image forming apparatus having a unit for accommodating a rotating body and capable of being pulled out and inserted into the main body of the apparatus, wherein the rotating body is a hollow cylindrical body having an open end wall portion at least on the rear side in the unit insertion direction. A holding member that engages with the opening portion of the hollow cylinder and holds the back side is provided on the apparatus body side, and when the unit is pulled out from the apparatus body, An image forming apparatus, wherein an engaging portion that engages with the hollow cylindrical body from the side is provided in the unit. 11. The image forming apparatus according to claim 10, wherein the engaging portion is provided so as not to come into contact with the rotating body when the unit is attached to the apparatus main body. 12. The image forming apparatus according to claim 10, wherein the engaging portion is composed of a facing member facing the opening end surface on the rear side in the unit insertion direction, and the unit is pulled out from the apparatus main body. The end of the hollow cylindrical body which is released from the holding member by the holding of the holding member is released by continuing the pulling-out of the unit while the facing member is engaged with the hollow cylindrical body from the back side in the unit insertion direction. A receiving portion for receiving the peripheral surface is provided on the unit, and
The image forming apparatus, wherein the unit is provided with pressing means for pressing the receiving portion and the end peripheral surface facing the receiving portion against each other. 13. The image forming apparatus according to claim 12, further comprising an operating member for restricting and releasing restriction of pulling out the unit from the apparatus main body, the pressing means being in a released state of the pressing and the pressing state. In the device main body set state of the unit, the pressing means is set to the release state of the pressing, and the operation member shifts from the restriction to the restriction release. An image forming apparatus comprising interlocking switching means for switching the state of the pressing means from the released state of the pressing to the pressed state in association with the operation for