JPH103237A - Photoreceptor cleaning device for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve and accuracy of the mounting position of a holder which holds a cleaning blade removing residual toner from the surface of a photoreceptor in an image forming device. SOLUTION: The holder 41 is formed so that its cross section is nearly inverted L-shaped, and mounted by setting the inner wall surface 44a of the outer wall part 44 of a case 17 as a mounting reference surface and the upper surface 44b of the wall part 44 as a mounting auxiliary surface. The surface 44a is provided with a machine screw hole 71 for fixing the holder 41 through a machine screw 70 and a pair of pins 72 for positioning. The holder 41 is provided with a machine screw hole 73 through which the machine screw 70 passes and a pin hole 74 through which the pin 72 passes. The position of the hole 71 is set on the outside of the flange part 18a of the photoreceptor 18 and the position of the pin 72 is set between the hole 71 and the side end of the cleaning blade 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoreceptor cleaning device for an image forming apparatus, and more particularly to a structure suitable for being housed in a case together with a photoreceptor, a developing device and the like and provided in a cartridge-shaped image forming unit. Regarding what was.

[0002]

2. Description of the Related Art In recent years, image forming apparatuses such as copiers and facsimile machines have been miniaturized. However, in order to meet the demand for miniaturization, a photoconductor, a developing device, An image forming unit is often configured by housing a charging device, a cleaning device, and the like in an integrated case, thereby contributing to downsizing of the entire image forming apparatus. With such a configuration, it is possible to make the life of each of the components such as the photosensitive member of the image forming system, the developing unit, the cleaning blade, the charging roller, and the toner recycle unit the same, thereby making it more economical. There is an advantage that it is only necessary to replace one unit at a time, instead of performing the operations at different times, and the handling becomes easy.

In order to reduce the size of such an image forming unit, it is necessary to reduce the size of many built-in elements. Naturally, a cleaning device for a photoreceptor is also an object. . To reduce the size of the cleaning device, a blade-type cleaning device that is small, inexpensive, and easily suppresses toner filming is often used. It is required to be configured so as to contact uniformly over the entire surface. Therefore, conventionally, a mechanism is employed in which the position, angle, and the like of the cleaning blade are movable, and the cleaning blade is uniformly brought into sliding contact with the surface of the photoreceptor using a pressing unit such as a spring.

However, from the viewpoint of miniaturization of the image forming unit, the size of the cleaning device is increased by the above-described movable mechanism and pressurizing means, which is contrary to the goal of miniaturizing the device. In order to solve this problem, the distance between the holder and the surface of the photoconductor may be reduced, and a cleaning blade having a short free length from a portion fixed to the holder to a portion contacting the surface of the photoconductor may be used. . However, the positional accuracy of the blade tip is required to be adjusted, for example, in units of 1/100 mm, and in order to satisfy this, it is necessary to finish the blade tip with a high-precision angle and straightness. However, in the case of a cleaning blade having a short free length, there is a problem that the amount of displacement of the blade tip position due to an error in the mounting position of the holder is larger than that of a cleaning blade having a long free length. That is, in the case of a cleaning blade having a long free length, even if there is a slight error in the mounting position, the error can be absorbed to some extent by the bending on the tip side, whereas it can hardly be expected in a cleaning blade having a short free length.

In addition, resource saving has become an important issue due to the recent increase in environmental protection consciousness. Even in an image forming apparatus, an image forming unit and other components are designed and manufactured so that they can be reused as much as possible. It has become to. Therefore, the cleaning blade cannot be reused because it needs to be replaced due to wear and deformation of the tip.However, a holder that can be reused by replacing the blade and that can be re-assembled after replacing the blade with high accuracy can be used. Is desired.

Accordingly, the present invention has been made in view of the above-mentioned conventional problems,
It is an object of the present invention to provide a photoconductor cleaning device for an image forming apparatus that can improve the mounting position accuracy of a holder in the case of a new build or reuse, and can assemble and assemble accurately even with a cleaning blade having a short free length. .

[0007]

According to a first aspect of the present invention, there is provided a photoconductor cleaning apparatus for an image forming apparatus, comprising:
In order to achieve the above object, a cleaning blade is attached via a holder fixed to a support portion facing the photoreceptor, and a tip of the cleaning blade is slid on the photoreceptor surface to remove residual toner on the photoreceptor surface. In the photoconductor cleaning device of the image forming apparatus configured to be scraped off, the fixing of the holder to the support portion is performed by a pair of screws, and the screw fixing position is set to a position outside the both ends of the photoconductor. Features.

According to a second aspect of the present invention, the support portion has a pair of pins for positioning the holder, and the positions of the pair of pins are respectively located inside the positions where both screws are fixed and both ends of the cleaning blade. And a hole for inserting the pin at a corresponding position of the holder.

According to a third aspect of the present invention, the holder has a substantially inverted L-shaped cross-sectional shape, and the support portion is a part of a photoreceptor surrounding case for holding the photoreceptor. The screw fixing position and the pin are provided on the surface of the portion facing the photoreceptor, and the photoreceptor facing surface is used as a mounting reference surface of the holder, and has a substantially inverted L-shaped cross section corresponding to the holder. As described above, the surface continuous with the surface facing the photoreceptor is provided as an attachment auxiliary surface.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image forming unit of an image forming apparatus according to the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing an appearance of an embodiment of an image forming unit using a photoreceptor cleaning device of an image forming apparatus according to the present invention, and FIG. 2 is an image forming unit, a transfer / separation device, a fixing device, etc. of FIG. FIG. 3 is an enlarged perspective view showing an attachment state of the photoconductor cleaning device according to the present invention to the case around the photoconductor in the image forming unit of FIG. 1, and FIG. FIG. 5 is a plan view schematically showing an attached state.
FIG.

In these figures, reference numeral 10 denotes an image forming unit, 11 denotes a transfer / separation device, and 12 denotes a fixing device. The image forming unit 10 is formed in a cartridge shape and is not shown in the drawing. It is removable.
Further, the transfer / separation device 11 includes a transfer roller 13 and is rotatable in a vertical direction in FIG.
The fixing device 12 includes a pressure roller 15 and a heating roller 16.

The illustrated image forming unit 10 includes a photosensitive member 1 inside a photosensitive member surrounding case (hereinafter simply referred to as a case) 17.
8, the charging roller 19 constituting the charging device, the developing device 2
0, a cleaning device 21, a toner recycling belt 22 for feeding the residual toner collected by the cleaning device 21 to the developing device 11, a toner conveying screw 42, an agent stirring member 43, and the like. In the drawing, reference numeral 37 denotes an upper cover attached so as to cover the case 17 to prevent a person from contacting the photoreceptor 18, the charging roller 19 and the like.

An image forming operation using the image forming unit configured as described above will be briefly described. First, with the image forming apparatus main body mounted at a predetermined position, the photosensitive member 18 is rotatable in the direction indicated by the arrow in FIG. 2 by a drive source (not shown). The surface is neutralized by irradiating static elimination light from a static elimination lamp (not shown), and the surface potential is averaged to a reference potential of, for example, 0 to -150V. Next, a high voltage is applied to the charging roller 19 which is in contact with the surface of the photoreceptor 18 to charge the photoreceptor 18, and the surface potential is set to, for example, about -1100V. Then, the charged potential surface is exposed, and the surface potential to form an image is, for example, 0 to 0.
A latent image portion of -290 V is formed.

When the latent image portion is moved to the position of the developing sleeve 23 of the developing device 20 by the rotation of the photosensitive member 18, the latent image portion is held on the surface of the developing sleeve 23 in which a bias of, for example, about -800 V is applied. The latent toner adheres, and the latent image portion is developed to become a toner image (visible image).

On the other hand, the transfer paper P fed from a paper feed unit (not shown) is moved by the registration roller pair 24 so that the front end of the transfer paper P and the front end of the toner image on the photoreceptor 18 coincide at the position of the transfer roller 13. The timing is adjusted, and the toner image on the photoconductor 18 is transferred to the transfer paper P by the transfer roller 13. The transfer paper P is conveyed between the pressure roller 15 and the heating roller 16 of the fixing device 12, where the transferred toner is fused to the transfer paper P by heat and pressure, and is transferred to a discharge tray (not shown) outside the apparatus. Discharge.

The residual toner remaining on the photoreceptor 18 after the image is transferred is scraped off by a cleaning blade 25 of a cleaning device 21, and the toner is adhered to the surface of the photoreceptor 18 and almost no residual toner is left. Move to The residual toner collected by the cleaning device 21 is transferred to the developing device 20 by the toner recycling belt 22.
Is transported to the developer agitating section 26, and is collected.
And the toner is recycled by supplying the toner to the developing sleeve 23 again.

The image forming unit 10 shown in FIG. 1 has an outer wall 4 of a case 17 which is located downstream in the direction of transport of the transfer paper P.
The toner conveying screw 42 is located inside the holder 4, and the holder 4 of the cleaning blade 25 is
1 is attached to the inner wall surface 44a of the outer wall portion 44. An inner wall surface 44a of an outer wall portion 44 serving as a support portion of the holder 41
Are provided with screw holes 71, 71 for fixing the holder 41 with a pair of screws 70, 70, and a pair of pins 72, 72 for positioning the holder 41.
Screw holes 73 and 73 for passing the screw 70 and pin holes 74 and 74 for passing the pin 72 are provided. The position of the screw hole 71 is a position outside the flanges 18a at both ends of the photosensitive member 18 and close to the side of the case 17, and the position of the pin 72 is inside the position of the screw hole 71 and the cleaning blade 25. , A position almost opposite to the flange portion 18a of the photoreceptor 18 in the illustrated example. When a screw is used to fix the holder 41, it seems that it is necessary to move the holder away from the surface of the photoconductor by an amount corresponding to the head of the screw. Since it is on the outside, such a necessity is not required, and the cleaning blade 25 can be arranged at a position sufficiently close to the photoconductor 18.

The holder 41 has a substantially inverted L-shaped cross section as shown in FIG.
4a is used as an attachment reference surface, and the upper surface 44b of the outer wall portion 44 is attached as an attachment auxiliary surface. Although not shown, a sponge-like sealing material may be attached to the lower surface of the upper surface portion 41a of the holder 41. In addition, both the front and back surfaces of the hanging surface portion 41b need to be manufactured and processed to the extent that the desired mounting accuracy can be achieved. Therefore, although not limited, it is preferable that the holder 41 be made of a rigid metal plate rather than a resin or the like that may be deformed.

The cleaning blade 25 is made of, for example, a resin plate having a thickness of 2 mm and is adhered to the surface of the hanging surface 41b of the holder 41 so that the leading edge can be slid on the surface of the photosensitive member 18. Make contact. In the drawing, reference numeral 75 denotes a sealing material, which is adhered to the surface of the hanging portion 41b of the holder 41 between the side end of the cleaning blade 25 and the pin hole 74, and the residual toner scraped off by the cleaning blade 25 is applied to the flange of the photosensitive member 18. It does not scatter to the part 18a side.

The operation of attaching the holder 41 to which the cleaning blade 25 is adhered to the case 17 is as follows.
In the case of a new construction, the cleaning is performed before the photoconductor 18 is attached to the case 17, and in the case of reusing after replacing the cleaning blade 25, the photoconductor 18 is removed, but in any case, the procedure is the same. is there. First, the upper surface portion 41a of the holder 41 is placed on the upper surface 44b of the outer wall portion 44 serving as an auxiliary mounting surface, and the pin hole 74 of the holder 41 is aligned with the corresponding pin 72 while shifting the position of the holder 41.
After the position of the pin hole 74 of the pin 72 is adjusted, the back surface of the hanging portion 41b of the holder 41 is brought into close contact with the inner wall surface 44a of the outer wall portion 44 of the case 17 serving as a mounting reference surface through the pin 72. In this state, the holder 41 can be accurately positioned. And in order to prevent the displacement of the holder 41,
From the surface side of the hanging surface portion 41b of the holder 41 to the hanging surface portion 4
1b and the screw 7 through the screw holes 73 and 71 of the inner wall surface 44a.
Screw 0 and tighten. In the positioning and fixing with the screws 70 alone, especially after the holder 41 is once removed, there is a possibility that a slight displacement may occur due to deformation of the screw holes 73 in the inner wall surface 44a, but the positioning with the pins 72 is also used. The deformation of the screw hole 73 and the screw 70
No change in the position of the holder 41 occurs even if the tightening state changes.

The structure of the embodiment of the present invention can employ either a trailing type or a leading type of contact between the leading edge portion of the cleaning blade 25 and the surface of the photoreceptor 18. 18 prevents uneven contact of the cleaning blade 25 with the cleaning blade 18,
Long life can be achieved.

The residual toner scraped off by the cleaning blade 25 is present on the outer wall portion 44. If heat from the heating roller 16 of the fixing device 12 is applied to the residual toner, the toner is denatured or adhered. In the case 17 of the embodiment, the outer wall portion 44 has a double wall structure as shown, and a gap 47 is formed between an inner wall 45 on the toner conveying screw 42 side and an outer wall 46 exposed to the outside. The heat existing in the fixing device 12 is shut off by the air present therein, and the strength of the case 17 is enhanced by the double wall structure.

[0023]

As described above, in the photoconductor cleaning device of the image forming apparatus according to the first aspect of the present invention, the fixing of the holder of the cleaning blade to the support portion is stopped by the screw, and the screw fixing position is set to be shorter than both ends of the photoconductor. Since the cleaning blade is located on the outer side, even a cleaning blade having a short free length can be mounted close to the photoconductor, which contributes to downsizing of the apparatus, and can increase the mounting position accuracy of the cleaning blade with respect to the photoconductor. This has the effect of extending the life of the device. In addition, since the holder can be easily mounted on the supporting portion even when the holder is newly built or when the cleaning blade is replaced after replacement, the recycling can be efficiently performed.

According to a second aspect of the present invention, there is provided a photoconductor cleaning device for an image forming apparatus, wherein the holder is positioned by pins provided on a support portion inside the screw fixing position and outside both ends of the cleaning blade. Therefore, in addition to the above-mentioned common effects, there is an effect that the positioning accuracy between the photosensitive member and the cleaning blade can be further improved, and a slight positional shift of the holder, which may be caused by screwing, can be prevented.

According to a third aspect of the present invention, there is provided a photoreceptor cleaning apparatus for an image forming apparatus, wherein a screwing position and a pin are provided on a surface of a support portion forming a part of a case around the photoreceptor facing the photoreceptor,
The photoconductor-facing surface is used as a mounting reference surface for a holder having a substantially inverted L-shaped cross section, and a surface connected to the photoconductor-facing surface so as to form an inverted L-shape is used as an auxiliary mounting surface. This has the effect that assembly can be performed very easily.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an appearance of an embodiment of an image forming unit using a photoconductor cleaning device of an image forming apparatus according to the present invention.

FIG. 2 is a cross-sectional view showing an arrangement of an image forming unit, a transfer / separation device, a fixing device, and the like in FIG.

FIG. 3 is an enlarged perspective view showing an attached state of a photoconductor cleaning device according to the present invention to a photoconductor surrounding case in the image forming unit of FIG. 1;

FIG. 4 is a plan view schematically showing a partially broken attachment state of FIG. 3;

FIG. 5 is a side sectional view of the same.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 image forming unit 11 transfer / separation device 12 fixing device 13 transfer roller 14 rotation fulcrum 15 pressure roller 16 heating roller 17 case around photoconductor 18 photoconductor 18a flange of photoconductor 19 charging roller 20 developing device 21 cleaning device 22 Toner recycling belt 23 Developing sleeve 24 Registration roller pair 25 Cleaning blade 26 Developer stirring section 37 Upper cover 41 Cleaning blade holder 41b Holder hanging surface 41a Holder upper surface 42 Toner transport screw 43 Agent stirring member 44 Outer wall 44a Outer wall Inner wall surface 44b Upper surface of outer wall portion 45 Inner wall 46 Outer wall 47 Void 70 Screw 71 Screw hole 72 Pin 73 Screw hole 74 Pin hole 75 Seal material P Transfer paper

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kenzo Tatsumi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Toshitaka Yamaguchi 1-3-6 Nakamagome, Ota-ku, Tokyo Share Inside Ricoh Company (72) Inventor Takeo Suda 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Company (72) Inventor Hiroshi Yoshinaga 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Company ( 72) Inventor Ken Amamiya 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (72) Inventor Mayumi 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd.

Claims (3)

[Claims] 1. A cleaning blade is attached via a holder fixed to a support portion facing a photoreceptor, and a tip of the cleaning blade is slid on the surface of the photoreceptor to scrape off residual toner on the surface of the photoreceptor. In the photoreceptor cleaning device of the image forming apparatus, the fixing of the holder to the support is a pair of screws,
A photoconductor cleaning device for an image forming apparatus, wherein the screw stop position is located outside of both ends of the photoconductor. 2. The support portion includes a pair of pins for positioning the holder, and the positions of the pair of pins are located inside the both screw fixing positions and outside the both end positions of the cleaning blade. 2. The apparatus according to claim 1, further comprising a hole for inserting said pin at a position corresponding to said holder. 3. The photoconductor according to claim 1, wherein the holder has a substantially inverted L-shaped cross section, the support portion is a part of a photoconductor surrounding case for holding the photoconductor, and the support portion faces the photoconductor. The screw fixing position and the pin are provided on the surface to be fixed, and the photosensitive member facing surface is used as a reference mounting surface of the holder, and the photosensitive member facing surface is formed to have a substantially inverted L-shaped cross section corresponding to the holder. 3. The photoconductor cleaning device for an image forming apparatus according to claim 2, wherein a surface connected to the photoconductor is used as an auxiliary mounting surface.