JP2005192076A - Optical writing apparatus and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the amount of toner or dust adhering to a dust protection member. <P>SOLUTION: Light emitted from an optical source accommodated in a cabinet 65 is irradiated on an image carrier via a dust protection member 69, which plugs up an aperture 68 of the cabinet 65. A shield member 87 covering the dust protection member 69 is arranged at the cabinet 65. The shield member 87 can move freely between a position for covering the dust protection member 69 and a position for exposing the dust protection member 69. Moving the shield member 87 to the position for covering the dust protection member 69 when light is not emitted from the optical source prevents the dust protection member 69 from toner and dust adhesion. Thereby, the amount of toner or dust adhering to the dust protection member 69 can be reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical writing device and an image forming apparatus.

  2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus such as a digital copying machine, high quality images, high speed, space saving, energy saving, and the like are required. Therefore, an optical system used in an optical writing device provided in the image forming apparatus. High-performance products are also being used.

  In an image forming apparatus, a developer such as toner is generally used, but toner scattering in the image forming apparatus cannot be completely eliminated. Further, dust is floating in the image forming apparatus. The optical writing device is very disliked by toner and dust because of its character, so the optical writing device stores each part of the light source etc. in the housing and seals the inside so that the toner and dust get inside the housing. Is preventing. The housing of such an optical writing device is provided with an opening through which a light beam emitted from the light source passes, and the opening is closed with a dustproof member through which light can pass.

  The dustproof member is exposed to the toner and dust in the image forming apparatus, and if the dust adheres to the dustproof member, the performance of the light forming apparatus may be deteriorated. Such a situation must be avoided because image quality may be deteriorated thereby.

  Patent Document 1 discloses a technique in which a cleaning member for a dust-proof member that is detachably provided in an opening is provided detachably on a holding portion.

  Patent Document 2 discloses a technique in which an optical member (dust-proof member) slidably provided in an opening and a cleaning member provided at one end of the opening are disclosed.

  According to these techniques, the dustproof member and the optical member can be cleaned by an operation of attaching and detaching the dustproof member and the optical member.

Japanese Utility Model Publication 1-155066 Japanese Patent No. 2949826

  However, since the techniques disclosed in Patent Document 1 and Patent Document 2 only remove toner and dust attached to the dust-proof member, the amount of toner and dust attached to the dust-proof member does not change.

  An object of the present invention is to reduce the amount of toner and dust adhering to a dustproof member.

  An object of the present invention is to enable cleaning of toner and dust adhered to a dustproof member with a simple configuration.

  According to a first aspect of the present invention, in the optical writing device for irradiating the image carrier with the light emitted from the light source accommodated in the housing through the dust-proof member that closes the opening of the housing, the dust-proof member is covered. A shielding member provided on the housing is movably provided between a position and a position at which the dustproof member is exposed.

  A second aspect of the present invention is the optical writing device according to the first aspect, further comprising a cleaning member attached to the shielding member and in contact with the dustproof member.

  According to a third aspect of the present invention, in the optical writing device according to the first or second aspect, a moving unit that moves the shielding member is provided.

  According to a fourth aspect of the present invention, there is provided the optical writing apparatus according to the third aspect, wherein the optical writing apparatus is attached to an image forming apparatus that forms an image by electrophotography, and the movement is performed when the image forming apparatus is not performing an image forming operation. The shielding member is positioned at a position that covers the dust-proof member by driving the part, and before the image forming apparatus starts an image forming operation, the shielding is performed at a position where the moving part is driven to expose the dust-proof member. Positioning means for positioning the member.

  According to a fifth aspect of the present invention, in the optical writing device according to the third or fourth aspect, the moving section biases the shielding member against the biasing force of the biasing means and the biasing force of the biasing means. And a drive unit that moves the shielding member.

  According to a sixth aspect of the present invention, in the optical writing device according to the third, fourth, or fifth aspect, when the image forming operation is not performed by the image forming apparatus, the position where the dustproof member is exposed and the dustproof member A cleaning means is provided for cleaning the dustproof member by reciprocating the shielding member using the moving portion between the position and the position covering the dust.

  According to a seventh aspect of the present invention, in an image forming apparatus that includes an image carrier on which a latent image is formed by irradiating light and performs image formation by an electrophotographic method, the image carrier is irradiated with light. The optical writing device according to 2, 3, 4, 5 or 6 is provided.

  According to the present invention, when the light is emitted from the light source, the shielding member can be moved to a position where the dust-proof member is exposed, and when the light is not emitted from the light source, the shielding member is moved to a position covering the dust-proof member. Can do. Then, by positioning the shielding member at a position covering the dustproof member, it is possible to prevent toner and dust from adhering to the dustproof member, thereby reducing the amount of toner and dust adhering to the dustproof member. it can. Further, since the dustproof member and the shielding member are provided in the casing, for example, the optical writing device can be easily assembled as compared with the case where they are provided on the main body case side of the image forming apparatus.

  According to the second aspect of the present invention, the cleaning member attached to the shielding member and in contact with the dustproof member is provided so that the toner or dust attached to the dustproof member is removed by moving the shielding member. Thus, the dustproof member can be cleaned with a simple configuration in which the cleaning member is simply attached to the shielding member.

  According to the fourth aspect of the present invention, when the image forming apparatus is not performing an image forming operation, the shielding member covers the dustproof member, so that it is possible to prevent toner and dust from adhering to the dustproof member. Thus, the amount of toner and dust adhering to the dustproof member can be reduced.

  According to the sixth aspect of the invention, since the dustproof member is cleaned when the image forming operation is not performed by the image forming apparatus, the dust on the dustproof member is removed and the image forming operation is performed well. can do.

  A first embodiment of the present invention will be described with reference to FIGS. 1 is a longitudinal sectional view schematically showing an image forming apparatus according to the present embodiment, FIG. 2 is a horizontal sectional view showing an optical writing apparatus, FIG. 3 is a longitudinal sectional view showing an optical writing apparatus, and FIG. 5 is an exploded perspective view showing the cover and the shielding unit of the writing device, FIG. 5 is an enlarged cross-sectional view showing a part of the mounting structure of the shielding unit in the cover, FIG. 6 shows the dustproof member and the shielding unit, ) Is a longitudinal sectional view showing a state in which the shielding member is in the open position, (b) is a longitudinal sectional view showing a state in which the shielding member is in the shielding position, and FIG. 7 is a plan view showing the drive unit.

  As shown in FIG. 1, four image forming units 3 (3Y, 3C, 3M, and 3K) and an optical writing device 4 that emits a light beam are provided at a substantially central portion inside the main body case 2 of the image forming apparatus 1. An intermediate transfer belt 5 is disposed. Each image forming unit 3 is a part that forms an image (toner image) of a different color. In the description of the present specification and drawings regarding these image forming unit 3 and the components of the image forming unit 3, Y, The subscripts C, M, and K indicate yellow, cyan, magenta, and black colors, respectively.

  The four image forming units 3Y, 3C, 3M, and 3K have different colors of images formed because the colors of toners used are different, and the basic structure is the same.

  Each image forming unit 3 includes a photoconductor 6 (6Y, 6C, 6M, 6K) which is an image carrier that is rotationally driven in the direction of the arrow in the figure, a charging unit 7 disposed around the photoconductor 6, and a developing unit 8. The cleaning unit 9 and the like are included.

  The photoreceptor 6 is formed in a cylindrical shape and is rotationally driven by a drive source (not shown). A photosensitive layer is provided on the outer peripheral surface portion of the photosensitive member 6, and the outer peripheral surface 6 a which is the surface of the photosensitive member 6 is a scanned surface. By irradiating the outer peripheral surface 6a of the photosensitive member 6 with the light beam emitted from the optical writing device 4, an electrostatic latent image corresponding to image information is written on the outer peripheral surface 6a of the photosensitive member 6.

  The charging unit 7 uniformly charges the outer peripheral surface 6 a of the photoconductor 6, and a non-contact type is used for the photoconductor 6.

  The developing unit 8 supplies toner to the photoconductor 6, and the supplied toner adheres to the electrostatic latent image written on the outer peripheral surface 6 a of the photoconductor 6, thereby causing the electrostatic latent image on the photoconductor 6. The toner image is visualized as a toner image, and a non-contact type is used for the photoreceptor 6.

  The cleaning unit 9 cleans residual toner adhering to the outer peripheral surface 6 a of the photoconductor 6, and a brush contact type in which a brush contacts the outer peripheral surface 6 a of the photoconductor 6 is employed.

  The intermediate transfer belt 5 is a loop belt formed with a resin film or rubber as a base, and a toner image formed on the photoreceptor 6 is transferred to the intermediate transfer belt 5. The intermediate transfer belt 5 is supported by rollers 11, 12, and 13 and is driven to rotate in the arrow direction. On the inner peripheral surface side (inside the loop) of the intermediate transfer belt 5, there are four pieces that press the intermediate transfer belt 5 against the photoreceptor 6 in order to transfer the toner image on each photoreceptor 6 onto the intermediate transfer belt 5. A transfer roller 14 is disposed. On the outer peripheral surface 6 a side (outside the loop) of the intermediate transfer belt 5, a cleaning unit 15 that cleans residual toner, paper dust, and the like attached to the outer peripheral surface 6 a of the intermediate transfer belt 5 is disposed.

  Below the four image forming units 3 and the optical writing device 4 in the main body case 2, a paper feed cassette 16 on which recording media (paper sheets) are stacked and held is disposed. The recording media stacked and held in the paper cassette 16 are separated and fed in order from the highest one.

  In the main body case 2, a conveyance path 17 is formed through which a recording medium separated and fed from the sheet feeding cassette 16 is conveyed. On the conveyance path 17, a paper feed roller 18a, a registration roller 18b, an intermediate transfer roller 19, a fixing unit 20, a paper discharge roller 21 and the like are arranged.

  The registration roller 18b is a roller that is rotationally driven intermittently at a predetermined timing. By intermittently driving the registration roller 18b, the recording medium that has been transported to the position of the registration roller 18b and stopped is sent to a transfer position sandwiched between the intermediate transfer belt 5 and the intermediate transfer roller 19. At this transfer position, the toner image on the intermediate transfer belt 5 is transferred to the recording medium. Here, the intermediate transfer belt 5 and the intermediate transfer roller 19 constitute a transfer portion.

  The fixing unit 20 is a part that fixes the toner image transferred onto the recording medium to the recording medium by applying heat and pressure. The recording medium on which the toner image is fixed in the process of passing through the fixing unit 20 is discharged onto a paper discharge tray 22 formed on the upper surface of the main body case 2 by a paper discharge roller 21.

  Such an image forming apparatus 1 is provided with a control unit 50 that includes a CPU, a ROM, and a RAM and also functions as a part of the optical writing device 4. The control unit 50 controls each unit of the image forming apparatus 1. Drive control intensively.

  Next, the optical writing device 4 will be described in detail. As shown in FIGS. 2 and 3, the optical writing device 4 is of a so-called counter scanning type, and has four laser light source units (LD units) 61 (61Y, 61C, 61M, 61K) that oscillate a light beam. And an optical deflector 62 that deflects and scans the light beam from each laser light source unit 61 in two symmetrical directions, and forms an image of the deflected and scanned light beam to a desired size on the photosensitive member 6, for example, an fθ lens. An image forming optical system 63, and a synchronization detecting means 64 for detecting the scanning start timing of the light beam. These parts are held in the housing 65. The housing 65 includes a housing main body 66 having an upper surface opening and a cover 67 that closes the upper surface of the housing main body 66. The cover 67 is provided with openings 68 through which the light beam passes, and a dustproof member 69 is attached to these openings 68. The dustproof member 69 is flat glass.

  In the laser light source unit 61, a semiconductor laser 70 that is a light source, a collimator lens (not shown) that substantially collimates the divergent light emitted from the semiconductor laser 70, and a semiconductor laser driving circuit board are held by a holding member 71. Configured.

  The optical deflector 62 includes a two-stage rotating polygon mirror 72, a polygon mirror motor 73 that rotates the rotating polygon mirror 72, a soundproof glass 74 that covers the rotating polygon mirror 72, and the like.

  The synchronization detection unit 64 includes an imaging lens 75, an electric circuit board 77 having a photoelectric element 76, and a holding member (not shown) that holds them.

  In this optical writing device 4, color-separated image data input from a document reading device (scanner) or an image data output device (personal computer, word processor, facsimile receiver, etc.) (not shown) is used as a light source driving signal. According to the conversion, the semiconductor laser 70 in each laser light source unit 61 is driven to emit a light beam. The light beam emitted from each laser light source unit 61 is deflected through the surface tilt correction aperture 78, the cylinder lens 79, and the mirror 80a (however, only for the light beams emitted from the laser light source units 61Y and 61K). The scanner 62 reaches the scanner 62 and is deflected and scanned in two symmetrical directions by a rotating polygon mirror 72 rotated at a constant speed by a polygon mirror motor 73.

  The light beams deflected and scanned in two directions by the rotating polygon mirror 72 of the optical deflector 62 pass through the imaging optical system 63, are folded back by the mirror 80b, and are passed through the dustproof member 69 for each color. The electrostatic latent image is written on the surface to be scanned of the photosensitive member 6 by irradiation. At this time, the irradiation angles of the four light beams to the photosensitive member 6 are substantially the same.

  On the other hand, the synchronization detection means 64 for determining the write start timing returns the light beam that has passed through the imaging optical system 63 by the synchronization detection mirror 81, and outputs a scanning start synchronization signal. Here, since the original meaning of the synchronization detection is to take the timing of the scanning light, the synchronization detection means 64 may be installed so as to receive the light beam prior to the normal scanning. In order to detect a change in the speed (or time) of one scan, a detection means may be provided at the rear end of the scan. FIG. 2 shows a configuration in which synchronization is obtained before and after such scanning.

  As shown in FIG. 3, a shielding unit 85 is attached to the cover 67 of the optical writing device 4.

  As shown in FIGS. 3 to 6, the shielding unit 85 includes a stay 86 made of sheet metal and a shielding member 87. The stay 86 is engaged with a pair of claw portions 88 provided on the cover 67, and is held by the claw portions 88 so as to be slidable with respect to the cover 67. The sliding direction guided by the claw portion 88 is an orthogonal direction B orthogonal to the deflection direction A in which the light beam is deflected by the optical deflector 62. A protrusion 89 that protrudes from the peripheral portion of the lower surface of the stay 86 is in contact with the upper surface of the cover 67. Thereby, the contact area between the stay 86 and the cover 67 is reduced, and the rigidity of the stay 86 is improved.

  The stay 86 is formed with four openings 90 facing the four dustproof members 69. The shielding member 87 is affixed to the cover 67 so as to extend to a part of the opening 90 for each of these openings 90, and the shielding member 87 is formed in a size that can cover the dust-proof member 69. ing. The shielding member 87 is a resin film, and an example of the resin film is black PET. The opening 90 of the stay 86 partially closed by these shielding members 87 is formed in such a size that the dust-proof member 69 can be exposed to the photosensitive member 6 side by the unblocked portion.

  As a result, the shielding member 87 exposes the dustproof member 69 through the opening 90 without covering the dustproof member 69 (FIG. 6A) and the position where the shielding member 87 covers the dustproof member 69 (FIG. 6B). ) Is slidable with respect to the cover 67.

  A cleaning member 91 that contacts the dust-proof member 69 is attached to the tip of the shielding member 87. The cleaning member 91 is formed of a non-woven fabric and contacts the entire area of the dustproof member 69 in the deflection direction A. The cleaning member 91 is pressed against the dust-proof member 69 due to the elasticity of the shielding member 87. The contact force of the cleaning member 91 with respect to the dust-proof member 69 can be changed by changing the inclination angle C of the stay 86 at the part where the shielding member 87 is attached.

  As shown in FIGS. 3 and 7, a drive unit 92 that is a moving unit is coupled to the stay 86 of the shielding unit 85. The drive unit 92 is attached to the housing 65. The drive unit 92 includes a motor 93 that is a power source and a gear group 94 that engages with the motor 93, and the pin 96 engages with a hole 95 formed in the stay 86 so that the gear 94 a rotates. By transmitting to the lever 97, the pin 96 is converted into a reciprocating motion in the orthogonal direction B of the pin 96. As a result, the stay 86 is moved in the orthogonal direction B. The drive unit 92 is not limited to this, and the stay 86 may be moved by a solenoid, for example.

  The drive unit 92 is provided with a sensor 98 that detects whether the stay 86 covers the dustproof member 69 or not. Specifically, the sensor 98 detects the position of the stay 86 by detecting a protrusion 99 provided on the upper surface of the stay 86. The controller 100 is connected to the motor 93 and the sensor 98 of the drive unit 92.

  The control unit 100 includes a CPU, a ROM, a RAM, and the like, and performs drive / stop control of the motor 93 based on a signal from the control unit 50 of the image forming apparatus 1 and a signal from the sensor 98.

  In such a configuration, each latent image formed on each photoconductor 6 by the optical writing device 4 is developed with each of the Y, M, C, and K toners of each developing unit 8 to be visualized. The visualized toner images of each color of Y, M, C, and K are transferred to a transfer material by the transfer unit. The transfer material onto which the four color images have been transferred is conveyed to the fixing unit 20, where the image is fixed by the fixing unit 20, and then discharged onto the paper discharge tray 22 by the paper discharge roller 21.

  The controller 100 of the optical writing device 4 drives the motor 93 to reciprocate the shielding unit 85 (cleaning means) before the image forming operation as described above is executed in the image forming apparatus 1. Specifically, the position where the shielding member 87 exposes the dustproof member 69 without covering the dustproof member 69 (see FIG. 6A), and the position where the shielding member 87 covers the dustproof member 69 (see FIG. 6B). The shielding unit 85 is reciprocated between the two. Thereby, the dust-proof member 69 reciprocates, whereby the cleaning member 91 removes the toner and dust on the dust-proof member 69. Finally, the shielding unit 85 is moved to a position where the shielding member 87 does not cover the dustproof member 69 and exposes the dustproof member 69 (positioning means, see FIG. 6A). As a result, the light beam can pass through the opening 90 of the stay 86.

  When the image forming operation is completed in the image forming apparatus 1, the motor 93 is driven to move the shielding unit 85 to a position where the shielding member 87 covers the dust-proof member 69 (positioning means, see FIG. 6B). ). Thereby, when the image forming operation is not performed, the dust-proof member 69 is covered with the shielding member 87. As the dust-proof member 69 moves in this way, the cleaning member 91 removes the toner and dust on the dust-proof member 69.

  The cleaning operation on the dust-proof member 69 by the reciprocating movement of the cleaning member 91 accompanying the reciprocating movement of the shielding member 87 is not limited to that performed before the image forming operation of the image forming apparatus 1 is executed. It may be executed after the image forming operation of the image forming apparatus 1.

  As described above, in the present embodiment, the dust-proof member 69 is covered with the shielding member 87, thereby preventing the toner and dust from adhering to the dust-proof member 69. The amount of dust can be reduced.

  Further, when the image forming apparatus 1 is not performing an image forming operation, the shielding member 87 is positioned at a position where the drive unit 92 covers the dustproof member 69. Therefore, when the image forming apparatus 1 is not performing an image forming operation, It is possible to prevent toner and dust from adhering to the member 69, thereby reducing the amount of toner and dust adhering to the dust-proof member 69.

  Further, the dust-proof member 69 can be cleaned with a simple configuration in which the cleaning member 91 is simply attached to the shielding member 87.

  In addition, since the dustproof member 69 is cleaned by the cleaning member 91 before or after the image forming operation by the image forming apparatus, the dust on the dustproof member is removed, and the image forming operation can be performed satisfactorily.

  In addition, since the dustproof member 69 and the shielding member 87 are collectively attached to the cover 67 constituting the housing 65, for example, compared with the case where they are provided on the main body case 2 side of the image forming apparatus 1, the optical writing The assembly of the insertion device is easy.

  In addition, since the drive unit 92 is provided in the optical writing device 4, the optical writing device 4 can be easily attached to the image forming apparatus 1.

  In the present embodiment, an example of a configuration in which a light beam is emitted from a single optical writing device 4 to a plurality of photoconductors 6 is shown, but the present invention is not limited to this. A configuration may be provided in which an individual optical writing device is provided for each. For example, four optical writing devices 4 are used for four photosensitive members 6.

  Next, although not particularly shown, a modification of the present embodiment will be described. In the present modification, the driving unit 92 that moves the shielding unit 85 of the optical writing device 4 is not the housing 65 of the optical writing device 4 but supports the main body side of the image forming apparatus 1, for example, the paper feed roller 18a. It is attached to the member 18c. Then, the control unit 50 of the image forming apparatus 1 controls the driving unit 92. Specifically, before executing the image forming operation, the motor 93 is driven to move the shielding unit 85 to a position where the shielding member 87 exposes the dust-proof member 69 without covering the dust-proof member 69. When the image forming operation is finished, the motor 93 is driven to move the shielding unit 85 to a position where the shielding member 87 covers the dust-proof member 69. Thereby, when the image forming operation is not performed, the dust-proof member 69 is covered with the shielding member 87.

  As described above, in this modification, it is not necessary to provide the drive unit 92 in the housing 65 of the optical writing device 4, so that the optical writing device 4 can be downsized. In addition, by doing this, it is possible to simplify the scooping of the motor 93 of the drive unit 92 and the harness of the sensor 98.

  Next, a second embodiment of the present invention will be described with reference to FIG. In addition, the part demonstrated in 1st embodiment is abbreviate | omitted with the same code | symbol. Here, FIG. 8 is a longitudinal sectional view showing the optical writing device 4 of the present embodiment.

  In the present embodiment, the structure for moving and positioning the shielding unit 85 is different from that of the first embodiment. As shown in FIG. 8, the optical writing device 4 of the present embodiment includes a coil spring 101 that is an urging means that is supported at both ends by a stay 86 and a housing body 66a of a shielding unit 85 and functions as a tension spring. Is provided. The coil spring 101 urges the stay 86 so that the shielding member 87 moves from a position where the dust-proof member 69 is exposed to a position where the dust-proof member 69 is covered. The coil spring 101 constitutes a moving unit 102 together with the driving unit 92. The housing body 66a is provided with a stopper member (not shown). The stopper member restricts the movement of the stay 86 in a direction from the position where the shielding member 87 exposes the dustproof member 69 toward the position covering the dustproof member 69 at the position where the shielding member 87 covers the dustproof member 69.

  In such a configuration, when positioning the shielding member 87 at a position where the dust-proof member 69 is exposed, the control unit 100 drives the drive unit 92 to move the stay 86 against the urging force of the coil spring 101. Thus, the shielding member 87 is positioned at a position where the dustproof member 69 is exposed. At this time, the driving force of the driving unit 92 and the biasing force of the coil spring 101 are balanced, and the shielding member 87 is maintained at a position where the dustproof member 69 is exposed.

  In addition, when the shielding member 87 is positioned at a position that covers the dustproof member 69 from this state, the control unit 100 stops driving the driving unit 92. As a result, the shielding member 87 is moved to a position that covers the dust-proof member 69 by the urging force of the coil spring 101 while receiving the resistance of the drive unit 92. Finally, the stay 86 is restrained from moving by a stopper member (not shown) at a position where the shielding member 87 covers the dust-proof member 69, so that the shielding member 87 is positioned at a position covering the dust-proof member 69.

  As described above, also in the present embodiment, the same operational effects as in the first embodiment can be obtained.

  In the present embodiment, the coil spring 101 has been described as an example of the urging unit. However, the urging unit is not limited to this, and the urging unit may be, for example, the weight of the shielding unit 85 that receives gravity.

  Further, in the present embodiment, the shielding member 87 is moved to a position where the dust prevention member 69 is exposed by the drive unit 92 and the shielding member 87 is moved to a position where the coil spring 101 covers the dust prevention member 69. Instead, the shielding member 87 may be moved to a position where the dust-proof member 69 is exposed by the coil spring 101, and the shielding member 87 may be moved to a position where the driving portion 92 covers the dust-proof member 69.

1 is a longitudinal sectional view schematically showing an image forming apparatus according to a first embodiment of the present invention. It is a horizontal sectional view showing an optical writing device. It is a longitudinal cross-sectional view which shows an optical writing device. It is a disassembled perspective view which shows the cover and shielding unit of an optical writing device. It is sectional drawing which expands and shows a part of attachment structure of the shielding unit in a cover. A dustproof member and a shielding unit are shown, (a) is a longitudinal sectional view showing a state where the shielding member is in the open position, and (b) is a longitudinal sectional view showing a state where the shielding member is in the shielding position. It is a top view which shows a drive part. It is a longitudinal cross-sectional view which shows the optical writing device of 2nd embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 4 Optical writing apparatus 6 Photosensitive body (image carrier)
65 Housing 68 Opening 69 Dust-proof member 70 Semiconductor laser (light source)
87 Shielding member 91 Cleaning member 92 Drive part (moving part)
101 Coil spring (biasing means)
102 Moving part

Claims (7)

In an optical writing apparatus that irradiates an image carrier with light emitted from a light source stored in a housing via a dustproof member that closes the opening of the housing,
An optical writing device, comprising: a shielding member provided in the housing so as to be movable between a position covering the dustproof member and a position exposing the dustproof member.   The optical writing device according to claim 1, further comprising a cleaning member attached to the shielding member and in contact with the dustproof member.   The optical writing apparatus according to claim 1, further comprising a moving unit that moves the shielding member. It is attached to an image forming apparatus that forms an image by electrophotography,
When the image forming apparatus is not performing an image forming operation, the moving unit is driven to position the shielding member at a position covering the dustproof member, and before the image forming apparatus starts the image forming operation, Positioning means for positioning the shielding member at a position where the dustproof member is exposed by driving a moving unit;
The optical writing device according to claim 3, further comprising:   The said moving part has a biasing means which biases the said shielding member, and a drive part which moves the said shielding member against the biasing force of this biasing means, The Claim 3 or 4 characterized by the above-mentioned. The optical writing device described.   When the image forming operation is not performed by the image forming apparatus, the dust-proof member is moved back and forth using the moving unit between the position where the dust-proof member is exposed and the position where the dust-proof member is covered. 6. The optical writing device according to claim 3, further comprising cleaning means for cleaning the member. In an image forming apparatus that includes an image carrier on which a latent image is formed by irradiating light and performs image formation by an electrophotographic method,
An image forming apparatus comprising the optical writing device according to claim 1, wherein the image bearing member is irradiated with light.

Images