JP2006276529A - Optical discharge device and image forming apparatus using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact and power saving optical discharge device by performing positioning of a light source provided on an apparatus body side and a light guide provided on a cartridge side with simple configuration, and to provide an image forming apparatus using it. <P>SOLUTION: The optical discharge device for discharging residual charge of a photoreceptor 1 by irradiating the surface of the photoreceptor 1 with light, comprises the light source 2 supported floatingly on the image forming apparatus body side, the light guide 3 positioned and fixed to a photoreceptor support member supporting the photoreceptor 1 and for introducing light from the light source 2 on the surface of the photoreceptor 1, and a positioning means 4 for positioning both by being provided between the light guide 3 and the light source 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical static elimination device used in an image forming apparatus such as a copying machine or a printer, and more particularly to an optical static elimination device used in an image forming apparatus of a type in which a process cartridge is attached to or detached from an image forming apparatus main body. The present invention relates to an improvement of the used image forming apparatus.

2. Description of the Related Art Conventionally, for example, in an electrophotographic image forming apparatus, particularly in an apparatus having a process cartridge detachably attached to an image forming apparatus main body, a light source is provided on the apparatus main body side, and a process cartridge side is provided on the process cartridge side. There has been known an optical static elimination device having a configuration including only a light guide (light guide) for irradiating light from a light source onto the photosensitive member in the process cartridge.
In such a light neutralizing device, light from the light source is converted into linear light on the surface of the photosensitive member through a light guide, so that the entire surface of the photosensitive member is uniformly matched to the photosensitivity of the photosensitive member. It was difficult to irradiate with a sufficient amount of light, the residual charge on the photoreceptor could not be sufficiently removed, and image defects such as ghosts were likely to occur.

For this reason, proposals have been made to devise the shape of the light guide and to irradiate the photoreceptor with a uniform amount of light (for example, see Patent Documents 1 and 2).
In Patent Document 1, a light guide having a substantially cylindrical shape is used, and a reflection portion having a substantially triangular cross section is provided on the opposite side of a portion of the light guide facing the photoconductor, and light emitted from a light source by the reflection portion. There has been a proposal to efficiently irradiate the photoconductor side. The light guide is positioned on the process cartridge side, while the light source (LED) is attached on the apparatus main body side.

JP 2003-295717 A (Embodiment of the Invention, FIG. 4) JP 2002-278395 A (Embodiment of the Invention, FIG. 1)

  However, in this method, the positioning of the light guide and the light source is determined by, for example, a variation error at the time of manufacturing and assembling. Therefore, in order to sufficiently remove the charge of the photosensitive member using the light guide, the assembly variation It is necessary to increase the light amount of the light source to compensate for the decrease in the light amount due to the above. For this reason, there is a risk of reducing the size and power saving of the apparatus.

On the other hand, in Patent Document 2, as shown in FIG. 9, a toner cartridge 305 having a light guide 306 (indicated by a broken line in the drawing) in which a photoconductor 302 and an LED 303 as a light source are fixedly disposed on the apparatus main body 301 side is a cartridge. A method is proposed in which the guide member 307 is slid and mounted in the direction of the arrow. At this time, since the light shielding member 304 made of an elastic body is disposed around the LED 303, the end surface of the light shielding member 304 comes into contact with the light incident surface of the light guide 306 when the toner cartridge 305 is mounted, and the light of the LED 303 is externally transmitted. In addition, the light guide 306 is effectively irradiated without leaking.
Furthermore, in this patent document, as shown in FIG. 10, there is also presented an attempt to use a hard light shielding member 308 and apply the end face of the light shielding member 308 to the light guide 306 by the urging force of the spring 309.

  However, in such a system, although the distance between the LED 303 and the light incident surface of the light guide 306 is constant, for example, if the optical axis of the LED 303 is to be aligned with the center of the light incident surface of the light guide 306, the apparatus main body 301. It is necessary to sufficiently increase the positioning accuracy. In order to allow a slight deviation, it is necessary to increase the amount of light of the LED 303 and perform photostatic discharge of the photosensitive member 302. Therefore, there are problems in terms of miniaturization and power saving. Furthermore, if a focusing lens or the like is added to the front surface of the LED 303 to increase the amount of incident light, the size of the apparatus will be increased.

  The present invention has been made to solve the above technical problem, and performs positioning of a light source provided on the apparatus main body side and a light guide provided on the process cartridge side with a simple configuration, It is an object of the present invention to provide a compact, power-saving optical static elimination device and an image forming apparatus using the same.

  That is, as shown in FIG. 1, the present invention is an optical charge eliminating device that irradiates light on the surface of the photosensitive member 1 to remove residual charges on the photosensitive member 1, and is floatingly supported on the image forming apparatus main body side. A light guide 3 that is positioned and fixed to a light source 2 and a photoconductor support member that supports the photoconductor 1 and that guides light from the light source 2 to the surface of the photoconductor 1, and is provided between the light guide 3 and the light source 2. And positioning means 4 for positioning the both.

In such technical means, the present case is directed to a mechanism relating to a positioning mechanism between the light guide 3 and the light source 2 of the light neutralizer when the process cartridge is mounted.
The light source 2 is not particularly limited as long as it has a light emission wavelength suitable for the sensitivity characteristics of the photoreceptor 1, but an LED is preferable from the viewpoint of miniaturization and power saving. Further, “floating support” in the present case means that the range that can follow not only the optical axis direction of the light source 2 but also the direction orthogonal to the optical axis has an allowable movement allowance (play). This makes it easier to position the light guide 3 and the light source 2, and makes it easier to position the light source 2 at the center of the light guide 3.
Further, the shape of the light guide 3 is not particularly limited as long as the light guide 3 can cover the effective width of the photoreceptor 1, and a normal light guide 3 can be used. Note that the light guide 3 may be subjected to processing such as prism lens processing so that effective light irradiation is performed on the photoreceptor 1.

The positioning means 4 in the present invention may be configured such that the light source 2 and the light guide 3 are detachably mounted. The positioning means 4 includes a light source holding member 5 that holds the light source 2 and a light guide. It is preferable that the body 3 is constituted by a light guide guide member 6 that is guided and held. At this time, one of the light source holding member 5 and the light guide guide member 6 has a positioning recess 7 and the other has a positioning projection. If the portion 8 is provided and can be detachably fitted to each other, the positioning of the both becomes easier. In this case, the positioning concave portion 7 and the positioning convex portion 8 may be either the light source holding member 5 or the light guide guide member 6 as the positioning concave portion 7 or any of the positioning convex portions 8.
Further, the light source holding member 5 is preferably elastically biased by an elastic member, which makes it possible to move the light source holding member 5 at the time of positioning, and facilitate floating support. become. Any elastic member may be used as long as it can elastically bias the light source holding member 5, and a typical embodiment includes a coil spring.

Further, in the present invention, it is preferable that at least a part of the positioning concave portion 7 or the positioning convex portion 8 is provided with an inclined portion that makes it easy to attach and detach each other. It will be possible to perform smoothly. It is more preferable that the inclined portion is provided in both the positioning concave portion 7 and the positioning convex portion 8.
Furthermore, in the aspect in which the light guide guide member 6 includes the positioning convex portion 8, the positioning convex portion 8 can also be used by the light guide 3. Thus, the light guide 3 is directly used for positioning. By doing so, the light guide member 6 can be made small, and the apparatus can be miniaturized. When positioning the light guide 3, it is necessary to prevent the light guide 3 from being adversely affected by scratches or the like.

In the present invention, the positioning means 4 is interlocked with the opening / closing operation of the opening / closing cover on the image forming apparatus main body side which has at least the photosensitive member 1 and allows the removable process cartridge to be attached to the image forming apparatus main body side. Thus, it is preferable that the light source holding member 5 can be moved to the light guide member 6 side. In this case, the positioning is completed when the opening / closing cover on the apparatus main body side is closed, thereby simplifying the structure. Will come to be.
Further, at this time, the present invention can be applied to a color image forming apparatus. A plurality of process cartridges are detachably attached to the image forming apparatus main body, and a plurality of light source holding members 5 are attached in conjunction with an opening / closing operation of the opening / closing cover. What is necessary is just to enable it to move to the some light guide guide member 6 side corresponding, respectively.

  Further, as the positioning means 4 for positioning by the opening / closing cover on the apparatus main body side, the light source holding member 5 slides on the side far from the light guide 3 in conjunction with the opening / closing operation of the opening / closing cover, and the light source holding member 5. It is preferable to provide a sliding member that moves the light source to the light guide 3 side, and sliding by this sliding member moves the light source holding member 5 to the light guide 1 side, thereby enabling positioning of both. In this case, from the viewpoint of smooth movement of the sliding member, it is preferable that at least the light source holding member 5 includes an inclined portion on which the sliding member can slide.

Furthermore, the present invention is not limited to the above-described photostatic device, but also targets an image forming apparatus. In this case, a process cartridge that is detachably attached to the main body of the image forming apparatus and includes a photoreceptor. And the above-described optical static elimination device provided between the process cartridge and the apparatus main body.
Furthermore, the present invention is also directed to an image forming apparatus including a photosensitive member and the above-described light static elimination device, and a process cartridge in which a light guide constituting the above-described optical static elimination device and a positioning unit thereof are incorporated. is there.

According to the present invention, the light source floated and supported on the image forming apparatus main body side and positioned and fixed to the photosensitive member supporting member that supports the photosensitive member separately from the image forming apparatus main body, and the light from the light source is guided to the surface of the photosensitive member. Since a positioning means for positioning the light guide and the light source is provided between the light guide and the light source, the light source can be easily aligned with the center of the incident surface of the light guide, and even if the amount of light is small A sufficient amount of irradiation light can be obtained to eliminate the residual charge on the body. Therefore, it is possible to provide a small-sized and power-saving optical static elimination device.
Further, by using such a light neutralizing device, it is possible to provide a small, power-saving image forming apparatus equipped with a process cartridge.
Furthermore, there is provided a small and power-saving image forming apparatus provided with the photosensitive member and the above-described light neutralizing device, and a small process cartridge incorporating a light guide body and positioning means constituting such a light neutralizing device. It becomes possible to do.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
Embodiment 1
FIG. 2 shows Embodiment 1 of an image forming apparatus to which the present invention is applied.
In the figure, the image forming apparatus is a so-called tandem type color image forming apparatus, and an image forming unit 22 (specifically, yellow, magenta, cyan, and black in this embodiment) is provided in the apparatus housing 21. 22a to 22d) are arranged in the vertical direction, and a paper feed cassette 23 for storing paper 24 for supply is arranged below the paper feed cassette 23, and a paper feed cassette is provided at a position corresponding to each image forming unit 22. 23, a sheet conveyance path 25 serving as a conveyance path for the sheet 24 from 23 is arranged in the vertical direction.

In the present embodiment, the image forming units 22 (22a to 22d) form toner images for yellow, magenta, cyan, and black in order from the upstream side of the sheet conveyance path 25, and various processes. A process cartridge 30 incorporating the unit and an exposure device 40 for irradiating the process cartridge 30 with scanning light for image formation are provided.
Here, the process cartridge 30 includes, for example, a photosensitive drum 31, a charging roll 32 that precharges the photosensitive drum 31, and an electrostatic device that is exposed and formed by the exposure device 40 on the charged photosensitive drum 31. A developing device 33 that develops the latent image with the corresponding color toner, a cleaning device 34 that removes waste toner on the photosensitive drum 31, and a light guide 35 that optically neutralizes the surface charge of the charged photosensitive drum 31. It is an integrated cartridge.
On the other hand, the exposure apparatus 40 stores a semiconductor laser (not shown), a polygon mirror 42, an imaging lens 43, a mirror 44, etc. in the case 41, deflects and scans the light from the semiconductor laser with the polygon mirror 42, and forms an imaging lens. 43, the light is guided to the exposure point on the photosensitive drum 31 through the mirror 44.

Further, in the present embodiment, a conveyance belt 53 that circulates along the sheet conveyance path 25 is disposed at a position corresponding to each photosensitive drum 31 of each image forming unit 22.
The conveyor belt 53 is made of a belt material (rubber or resin) that can electrostatically attract the paper 24, and is stretched between a pair of tension rolls 51 and 52. The rack roll 52 is a driving roll, and the lower tension roll 51 is a driven roll.

  Furthermore, a paper suction roll 54 is disposed at the entrance portion of the transport belt 53 (the portion facing the stretching roll 51), and by applying a high voltage suction voltage to the paper suction roll 54, the transport belt 53. The sheet 24 is attracted to the sheet. Further, a transfer roll 50 is disposed on the back side of the conveyance belt 53 corresponding to the photosensitive drum 31 of each image forming unit 22, and the sheet 24 on the photosensitive drum 31 and the conveyance belt 53 is transferred by the transfer roll 50. And more closely. A predetermined transfer bias from a transfer bias power supply (not shown) is appropriately applied between the transfer roll 50 and the photosensitive drum 31.

In the present embodiment, a pick-up roll 61 that sends out the paper 24 at a predetermined timing is provided in the vicinity of the paper feed cassette 23, and is sent to the transfer position via the transport roll 62 and the registration roll 63. It is like that.
Further, a fixing device 64 is provided in the paper conveyance path 25 located on the downstream side of the most downstream image forming unit 22d, and a discharge roll 66 for discharging paper is provided on the downstream side of the fixing device 64. The discharged paper is stored in a storage tray 67 formed on the upper portion of the apparatus housing 21.
In FIG. 2, reference numeral 80 denotes a high-voltage power supply that supplies a high voltage to the high-voltage device, and reference numeral 81 denotes a low-voltage power supply that supplies a low voltage to the low-voltage device.

The image forming process of such an image forming apparatus is as follows.
As shown in FIG. 2, in each image forming unit 22 (22 a to 22 d), after the photosensitive drum 31 is charged by the charging roll 32 and a latent image is formed on the photosensitive drum 31 by the exposure device 40. A visible image (toner image) is formed by the developing device 33.
On the other hand, the paper 24 from the paper feeding cassette 23 is fed out at a predetermined timing by the pickup roll 61, sent to the suction position of the transport belt 53 through the transport roll 62 and the registration roll 63, and sucked by the transport belt 53. In this state, it is sent to the transfer position.
Then, the toner images on the photosensitive drum 31 in each image forming unit 22 are respectively transferred to the paper 24 by the transfer roll 50, and each color component unfixed toner image on the paper 24 is fixed by the fixing device 64 and then fixed. The used paper 24 is discharged to the storage tray 67.

FIG. 3 shows details of the process cartridge 30 used in the present embodiment.
In the figure, a process cartridge 30 includes a photosensitive drum 31, a charging roll 32, a part of a developing device 33, and a cleaning device 34 as well as a light guide as a light guide for photostatic discharge of the photosensitive drum 31 before cleaning processing. A photosensitive cartridge 30a including a guide 35 and a lower portion of the photosensitive cartridge 30a are provided so as to be swingable and positioned with respect to the photosensitive cartridge 30a and include a main part of the developing device 33. And a developing cartridge 30b.

In particular, in the present embodiment, the developing device 33 includes a developing unit 100 that faces the photosensitive drum 31 and visualizes the electrostatic latent image on the photosensitive drum 31 with a developer including toner and a carrier. The toner supply units 110 and 120 for supplying toner to the developing unit 100 (in this embodiment, a separate type from the main toner supply unit 110 and the sub toner supply unit 120 are used) are provided.
The photosensitive cartridge 30a has a configuration in which a cleaning unit in which the cleaning device 34 is unitized and a sub-toner replenishment unit 120 are integrated in the horizontal direction, and the development cartridge 30b has a development unit 100 and a main toner replenishment unit 110. Are integrated in the horizontal direction. In the figure, reference numeral 103 denotes a developing roll for developing the photosensitive drum 31.

  Further, in the present embodiment, the developing cartridge 30b is provided so as to be swingable by the pivot shaft 30c of the developing unit 100 relative to the photosensitive cartridge 30a positioned and fixed to the apparatus housing 21, and the photosensitive cartridge 30a. A scanning passage 135 through which scanning light from the exposure device 40 can pass is secured between the developing cartridge 30b and an elastic member on both sides of each part cartridge 30a, 30b near the entrance of the scanning passage 135. A spacer 130 is interposed to pressurize the developing cartridge 30b against the photosensitive cartridge 30a. Of course, a biasing element such as a biasing spring may be used instead of or in addition to the spacer 130.

In the present embodiment, the sub-toner replenishment unit 120 of the photoconductor cartridge 30a extends in a direction orthogonal to the axial direction of the photoconductor drum 31, as shown in FIGS. 3 and 4A and 4B, for example. A pair of support protrusions 141 are provided.
When the process cartridge 30 is mounted in a cartridge receiving portion (not shown) of the apparatus housing 21, both ends of the support shaft of the photosensitive drum 31 are predetermined by a fixed receiving member (not shown) provided in the cartridge receiving portion. A drive transmission member (drive transmission gear) disposed at one end of the photosensitive drum 31 that is fixed in position and rotatable with respect to the support shaft is connected to a drive system (not shown) provided in the cartridge receiver. Connect and engage. The pair of support protrusions 141 are engaged with engaged portions (such as recesses and holes) of the cartridge receiving portion so that the photosensitive cartridge 30 a is positioned and fixed to the apparatus housing 21. Here, the cartridge receiving portion of the apparatus housing 21 may be any as long as it can accommodate and hold the process cartridge 30, and may be configured using the housing frame itself, or may be configured by providing another member on the housing frame. May be.
In particular, in the present embodiment, the support protrusion 141 is provided on the unit outer wall away from the photosensitive drum 31 and is positioned with respect to a direction different from the axial direction of the photosensitive drum 31. The photoreceptor cartridge 30a can be stably supported. Further, a pair of the support protrusions 141 are provided, the support points of the photosensitive cartridge 30a are set to four, the weight burden of the process cartridge 30 at each support point is reduced, and the twist deformation of the process cartridge 30 is also corrected. It is like that.
In FIG. 4, reference numeral 142 denotes a gripping arm used when the process cartridge 30 is attached and detached.

In particular, the light static eliminator in the present embodiment is composed of a light guide 35 disposed in the process cartridge 30 and a lamp unit 200 for supplying light to the light guide 35. FIG. ).
The light guide 35 is a rod-shaped member made of a translucent material such as acrylic resin, and a white cover 35b made of plastic such as ABS resin or PS resin, except for a portion of the peripheral surface thereof facing the photosensitive drum 31. The end surface on the lamp unit 200 side is an incident surface 35a. In this embodiment, the light guide 35 itself is not processed at all. However, for example, prism processing or the like may be performed to effectively guide light entering from the incident surface to the surface of the photosensitive drum 31. Absent.
Such a light guide 35 is accommodated on the process cartridge 30 side for each white cover 35 b and is disposed at a predetermined position with respect to the photosensitive drum 31. A part of the light guide 35 on the incident surface 35 a side protrudes from the process cartridge 30.

On the other hand, in the lamp unit 200, an LED 201 having a wavelength matching the photosensitivity of the photosensitive layer of the photosensitive drum 31 is fixedly accommodated in a lamp housing 202 made of an injection molded product such as ABS resin, and its two terminals. Is connected to a power source not shown.
Further, a ring-shaped protrusion 202a is provided on the outer peripheral surface of the lamp housing 202, and a coil spring 204 as an elastic member is interposed between the protrusion 202a and a stopper 203 fixedly disposed on the apparatus housing 21. Has been. Accordingly, the lamp housing 202 can be moved in the optical axis direction, and the LED 201 is also moved simultaneously. The ring-shaped protrusion 202a is restricted by a member (not shown) fixedly arranged on the apparatus housing 21 side so that the lamp housing 202 does not move too much to the light guide 35 side.
Further, in the present embodiment, an inclined portion 202b for facilitating the attachment / detachment of the light guide 35 is provided at both ends of the outer peripheral surface and the inner peripheral surface at a part of the end of the lamp housing 202 in the direction of the light guide 35. It has been.
In this embodiment, by adopting such a configuration, the lamp unit 200 side constitutes a positioning concave portion, and the light guide 35 side constitutes a positioning convex portion.

  5B and 5C, when the light guide 35 and the lamp unit 200 arranged in the state shown in FIG. 5A set the process cartridge 30 (see FIG. 3), the light guide 35 is moved to an arrow. It is the figure which showed the process of the change when moving to A direction, (b) shows the step which the light guide 35 contacted the lamp housing 202, (c), the light guide 35 was fitted to the lamp housing 202. The stage where the light guide 35 and the LED 201 are positioned is shown.

In (b), the light guide 35 slides on the inclined portion 202 b on the outer peripheral surface side of the lamp housing 202 and is positioned on the end surface of the lamp housing 202. At this time, the lamp housing 202 moves in the arrow B direction against the urging force of the coil spring 204. Further, when the light guide 35 moves in the direction of arrow A, the light guide 35 is positioned after sliding on the inclined portion 202b on the inner peripheral surface side of the lamp housing 202, as shown in (c). Then, the lamp housing 202 moves in the C direction, and the tip of the LED 201 and the incident surface 35a of the light guide 35 reach a predetermined position.
In the present embodiment, since a gap is provided between the lamp housing 202 and the stopper 203, the lamp housing 202 can move somewhat in the moving direction of the light guide 35, and the lamp housing 202 and the light Even if a deviation due to an assembly error or the like with the guide 35 occurs, the deviation can be absorbed, and the optical axis of the LED 201 can be aligned with the approximate center of the incident surface 35 a of the light guide 35.
Therefore, the amount of light emitted from the LED 201 can be effectively guided to the light guide 35, and an optical static eliminator effective for downsizing and power saving of the apparatus can be realized.
In this embodiment, it goes without saying that it is necessary to prevent the incident surface 35a of the light guide 35 from being damaged.

When the process cartridge 30 is removed, the positioning of the light guide 35 can be easily released by moving the light guide 35 in the direction opposite to the above-described direction.
In the present embodiment, the lamp unit 200 side is a positioning recess, and the light guide 35 side is a positioning projection. On the contrary, the lamp unit 200 side is a positioning projection and the light guide 35 side. It is also possible to configure so as to be a positioning recess, and it goes without saying that the same effect as the above-described configuration can also be obtained in this case.

Embodiment 2
6 (a) and 6 (b) show a second embodiment of an optical static eliminating device to which the present invention is applied. In the drawing, the alignment mechanism between the light guide 35 and the lamp unit 200 is substantially the same as that of the first embodiment. However, in this embodiment, the incident surface 35a of the light guide 35 does not contact the lamp housing 202 at the time of alignment. This is different from the first embodiment. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and the detailed description is abbreviate | omitted.

In the present embodiment, the cover 35b provided on the outer peripheral surface of the light guide 35 includes an inclined portion 35c on the outer peripheral surface of the end portion. Therefore, when the light guide 35 moves in the direction of arrow A (moves in accordance with the movement of the process cartridge 30 (not shown)), the inclined portion 35c and the inclined portion 202b on the outer peripheral surface side of the lamp housing 202 slide. As a result, the lamp housing 202 moves in the arrow B direction. Then, when the movement further continues and the inclined portion 35c on the outer peripheral surface of the cover 35b of the light guide 35 slides on the inclined portion 202b on the inner peripheral surface side of the lamp housing 202, the lamp housing 202 is moved by the biasing force of the coil spring 204 It moves in the opposite direction (moves in the direction opposite to arrow B in the figure).
When the peripheral surface of the cover 35b of the light guide 35 finally reaches the stopper portion 202c of the lamp housing 202, the movement is stopped. At this time, it goes without saying that the process cartridge 30 has been mounted in the apparatus housing 21.
As a result, the incident surface 35a of the light guide 35 is positioned at a position that matches the optical axis of the LED 201, as shown in FIG.

  Also in the present embodiment, since there is a gap between the lamp housing 202 and the stopper 203 that holds the coil spring 204, the positioning fit is good. Further, since the light guide 35 and the LED 201 maintain a substantially sealed space by the cover 35b and the lamp housing 202, respectively, the light of the LED 201 does not leak to the outside. For example, the photosensitive drum 31 (see FIG. 3). It becomes possible to prevent the influence on etc.

Furthermore, for example, when removing the process cartridge 30 from the apparatus housing 21, the light guide 35 may be moved in the direction opposite to the above-described direction (the direction of arrow A in FIG. 6A). In addition, the inclined portion 35c of the cover 35b of the light guide 35 and the inclined portion 202b on the inner peripheral surface side of the lamp housing 202 form a favorable sliding surface, and the lamp housing 202 easily moves against the urging force of the coil spring 204. By doing so, both positioning can be cancelled | released.
Thus, also in this embodiment, the same effect as in the first embodiment is obtained. Further, there is no fear of causing damage to the incident surface 35a of the light guide 35.

  In this embodiment, the lamp unit 200 side has a positioning recess and the light guide 35 side has a positioning projection. However, the lamp unit 200 side has a positioning projection and the light guide 35 side has a positioning recess. It goes without saying that it is also possible.

Embodiment 3
FIG. 7 shows an image forming apparatus on which the third embodiment of the light neutralizing apparatus to which the present invention is applied is mounted. In the figure, the image forming apparatus according to the present embodiment is configured in substantially the same manner as the image forming apparatus according to the first embodiment (see FIG. 2). In the present embodiment, for example, the process cartridge 30 is attached and detached. An opening / closing door 21a is provided in a part of the device casing 21, and the opening / closing door 21a is in an open state. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and detailed description is abbreviate | omitted here.

  In the present embodiment, the open / close door 21a can be opened with a pivot 21b provided below the apparatus housing 21 as a fulcrum. Further, on the opening / closing door 21a side, a conveying belt 53 stretched between two stretching rolls 51 and 52, and a transfer roll 50 arranged inside the conveying belt 53 are provided by a bracket or the like not shown. It is fixed. Further, on the side of the opening / closing door 21a, an interlocking plate 211 (211a to 211d) is provided so as to be positioned in the vicinity of the light guide 35 in the process cartridge 30 when the opening / closing door 21a is closed. 211 moves according to the movement of the door 21a.

FIGS. 8A and 8B show the positioning mechanism of the light static eliminator in the present embodiment. FIG. 8A shows a stage where the open / close door 21a is about to be closed after the process cartridge 30 is mounted. (B) has shown the stage where the door 21a was closed.
The light guide 35 in the present embodiment is provided with an inclined portion 35d along the inner peripheral surface at the end of the cover 35b. The inclined portion 35d has a concave shape that is recessed toward the incident surface 35a of the light guide 35. It has become.
On the other hand, in the lamp unit 200, unlike the first and second embodiments, the projection 202a of the lamp housing 202 is located in a direction away from the light guide 35 side, and a stopper fixedly disposed on the apparatus housing 21 on the light guide 35 side. 203 is provided.
Further, an inclined portion 202 d is provided on the peripheral surface on the light guide 35 side of the lamp housing 202, and the lamp housing 202 has a convex shape with respect to the light guide 35. Furthermore, the other end side of the lamp housing 202 has a convex shape (substantially conical shape) provided with an inclined portion 202e on the peripheral surface.

In addition, the interlocking plate 211 fixedly arranged on the opening / closing door 21a side is provided with an inclined portion 212 at a tip end portion directed toward the lamp unit 200 side.
In such a configuration, when the interlocking plate 211 is moved in the direction of arrow D in the figure by the closing operation of the open / close door 21a and the inclined portion 212 of the interlocking plate 211 reaches the inclined portion 202e of the lamp housing 202, the lamp housing 202 is moved. It moves in the direction of arrow E (moves in the direction of the light guide 35).
Then, when the inclined portion 212 of the interlocking plate 211 is passed, the movement of the lamp housing 202 is stopped as shown in (b). At this time, the positioning convex portion constituted by the lamp housing 202 fits into the positioning concave portion on the light guide 35 side and includes the inclined portions 202d and 35d, so that positioning fitting between both is easy. Will be made.

When the opening / closing door 21a is opened, the interlocking plate 211 moves in the opposite direction, and the lamp housing 202 is separated from the light guide 35 by the restoring force of the coil spring 204. There is no particular hindrance.
Also in this embodiment, since the LED 201 and the incident surface 35a of the light guide 35 are positioned well, an optical static elimination device that is reduced in size and power consumption can be achieved.
In the present embodiment, when the interlocking plate 211 is inserted, the movement amount of the lamp housing 202 is determined by the inclined portion 212 of the interlocking plate 211. If an elastic member is provided between 202 and the interlocking plate 211 (it is preferable that the interlocking plate 211 is slidable on the interlocking plate 211 side), errors due to assembly accuracy and the like can be absorbed. The shape at the time of fitting with the guide 35 can be further stabilized.

  Also in the present embodiment, it is needless to say that the lamp unit 200 side can be a positioning concave portion and the light guide side can be a positioning convex portion.

It is explanatory drawing which shows the optical static elimination apparatus which concerns on this invention. 1 is an explanatory diagram showing Embodiment 1 of an image forming apparatus according to the present invention. FIG. 3 is an explanatory diagram showing details of a process cartridge used in the first embodiment. (A) is the arrow view which looked at the process cartridge used in Embodiment 1 from the one side, (b) is the arrow view which looked at (a) from the other side of the opposite side. It is explanatory drawing which shows the outline | summary of the optical static elimination apparatus of Embodiment 1, (a)-(c) shows the progress order at the time of process cartridge mounting | wearing. (A) (b) is explanatory drawing which shows the outline | summary of the optical static elimination apparatus which concerns on Embodiment 2. FIG. 6 is an explanatory diagram illustrating an image forming apparatus according to Embodiment 3. FIG. FIG. 6 is an explanatory diagram showing an outline of an optical static elimination device used in a third embodiment. It is explanatory drawing which shows the outline | summary of the conventional optical static elimination apparatus. It is explanatory drawing which shows the outline | summary of the other conventional optical static elimination apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Photosensitive body, 2 ... Light source, 3 ... Light guide, 4 ... Positioning means, 5 ... Light source holding member, 6 ... Light guide guide member, 7 ... Positioning recessed part, 8 ... Positioning convex part

Claims (13)

A photostatic device that irradiates light on the surface of a photoconductor to neutralize residual charges on the photoconductor,
A light source floatingly supported on the image forming apparatus main body side;
A light guide that is positioned and fixed to a photoconductor support member that supports the photoconductor and guides light from the light source to the surface of the photoconductor;
An optical static elimination device comprising a positioning means provided between the light guide and the light source for positioning both. The light static eliminator according to claim 1,
The positioning means is composed of a light source holding member that holds a light source and a light guide guide member that guides and holds the light guide. The light static eliminator according to claim 2,
The light neutralizing device, wherein the light source holding member is elastically biased by an elastic member. The light static eliminator according to claim 2,
The positioning means has a positioning recess on one of the light source holding member and the light guide guide member, and has a positioning protrusion on the other, and is detachably fitted to each other. The light static eliminator according to claim 4.
At least a part of the positioning concave portion or the positioning convex portion is provided with an inclined portion that facilitates mutual attachment and detachment. In the aspect in which a light guide guide member is provided with a positioning convex part among optical static elimination devices according to claim 4,
The light-eliminating device, wherein the positioning convex portion is also used as a light guide. The light static eliminator according to claim 2,
The positioning means includes at least a photosensitive member and allows the light source holding member to guide the light source in conjunction with the opening / closing operation of the opening / closing cover on the image forming apparatus main body side that allows the removable process cartridge to be attached to the image forming apparatus main body side. An optical static eliminator capable of moving toward a guide member. The light static eliminator according to claim 7,
A plurality of process cartridges are detachably attached to the image forming apparatus main body, and the plurality of light source holding portions can be moved to the corresponding plurality of light guide guide members in conjunction with the opening / closing operation of the opening / closing cover. A characteristic light neutralizing device. The light static eliminator according to claim 7,
The positioning means includes a sliding member that slides on the side of the light source holding member far from the light guide in conjunction with the opening / closing operation of the opening / closing cover and moves the light source holding member to the light guide side. Photostatic device. The light static eliminator according to claim 9,
The light neutralizing device, wherein the light source holding member includes a slope on which a sliding member can slide. A process cartridge detachably attached to the image forming apparatus main body and including a photoconductor;
An image forming apparatus comprising: the light neutralizing apparatus according to claim 1 provided between the process cartridge and the image forming apparatus main body. A photoreceptor,
An image forming apparatus comprising: the light neutralizing device according to claim 1.   2. A process cartridge comprising a light guide and a positioning means for constituting the light neutralizing device according to claim 1.

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