JP4641547B2 - Optical scanning device - Google Patents

Description

  The present invention relates to an optical scanning device that emits laser light onto a surface to be scanned and deflects and scans the surface to be scanned.

  An optical scanning device used in an image forming apparatus such as a laser beam printer reflects a laser beam such as a laser beam by a rotating polygon mirror that rotates at high speed, deflects and scans the laser beam, and condenses the obtained scanning light on a photosensitive drum. Forming an electrostatic latent image.

  Next, the electrostatic latent image on the photosensitive member is visualized as a toner image by a developing device, transferred to a recording medium such as a sheet material, sent to a fixing device, and the toner on the recording medium is heated and fixed to fix the image. Formation takes place.

  In such a configuration, if dust or the like enters the optical scanning device, the dust or the like may adhere to each optical member in the optical scanning device, thereby reducing the scanning accuracy of the scanning light. And when the precision of scanning light falls, image quality will fall.

  Therefore, conventionally, various measures have been taken for this type of optical scanning device to prevent dust or the like floating in the image forming apparatus main body from entering the optical scanning device. Patent Document 1 discloses an optical scanning device according to a conventional example.

The optical scanning device according to the conventional example eliminates a gap between the scanning lens and the lid by bringing an elastic member serving as a dust-proof member into contact with the outer peripheral portion of the scanning lens, and increases the sealing degree of the optical scanning device.
JP 2007-304165 A

  However, the optical scanning device according to the conventional example has the following problems.

  First, since the dustproof member is made of a soft urethane foam or the like having a low bending strength, there is a problem that the assembling workability to the optical scanning device is poor. In addition, it is common to use double-sided tape in fixing the dustproof member, and if there is an assembly error, if you try to peel off the tape and regenerate it, the dustproof member with low bending strength may be damaged, The problem of low recyclability also arises.

  In order to solve the above problems, for example, there is a means of attaching the dustproof glass to the opening of the optical box and closing the optical scanning device. However, when attaching the dustproof glass, the influence of the surface accuracy of the dustproof glass, etc. This causes another problem that the optical characteristics deteriorate.

  Another means of increasing the size of the dust-proof member and securing the bending strength to improve the assembly workability is also conceivable, but in that case, the optical scanning device is increased in size and the image forming apparatus main body is also increased in size. Problems arise.

  Therefore, in view of the present situation, the present invention is an optical scanning device to which a dustproof member having a simple configuration is attached, closes the inside of the device main body without deteriorating optical characteristics, and improves the workability of attaching the dustproof member. An object is to provide an optical scanning device excellent in recyclability.

In order to achieve the above object, the present invention provides:
A light source that emits laser light;
A deflecting member for deflecting the laser light emitted from the light source;
An imaging member for imaging a laser beam emitted from the light source;
An optical box for holding the light source, the deflection member, and the imaging member;
A lid of the optical box;
With
In an optical scanning device in which laser light is emitted from a plurality of openings formed in the lid to a scanned surface outside the apparatus main body, and the scanned surface is deflected and scanned.
The dustproof member unit dusts from the openings prevents from entering the inside of the apparatus main body, on the inner side of the lid, the first opening of the lid, one for two openings of the second opening is provided,
The dustproof member unit is
A first dustproof member having an opening having an opening width of d2, a second dustproof member,
The first dustproof member and the second dustproof member are attached, and an opening having an opening width d1 is formed at a position corresponding to the opening provided in each of the first dustproof member and the second dustproof member, and the dustproof One sheet member formed of a material having higher bending strength than the member;
D2 <d1, and
The opening of the first dustproof member and the opening of the second dustproof member are positioned so as to face the first opening and the second opening formed in the lid, and the first opening and the second opening And the sheet member is fixed between
The peripheral edge of the opening of the first dustproof member and the peripheral edge of the opening of the second dustproof member are
Among the imaging members, the first dust-proof member is located at the most downstream position on the optical path and is in contact with the first and second imaging members facing the first opening and the second opening. Part, the opening of the second dust-proof member is blocked by the first imaging member, the second imaging member,
Furthermore, the first dust-proof member and the second dust-proof member abut on the lid,
It is characterized by being capable of closing the inside of the apparatus main body.

  According to the present invention, an optical scanning apparatus to which a dustproof member having a simple configuration is attached, the inside of the apparatus main body is closed without deteriorating optical characteristics, the workability of attaching the dustproof member is improved, and recyclability is also achieved. An excellent optical scanning device can be provided.

  The best mode for carrying out the present invention will be exemplarily described in detail below based on the embodiments with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. Absent.

  An optical scanning device according to an embodiment of the present invention will be described with reference to FIGS.

(Schematic configuration of image forming apparatus)
A schematic configuration of an image forming apparatus to which the optical scanning device S according to the present embodiment is applied will be described with reference to FIG. FIG. 2 is a schematic configuration diagram of a cross section of the image forming apparatus according to the present embodiment.

The image forming apparatus according to the present embodiment includes four photosensitive drums (image carriers) 1Y, 1M, 1C, and 1Bk arranged at equal pitches in the vertical direction. (Magenta), C (cyan), and Bk (black) toners are supported. Then, the toner images formed on the surfaces of the respective photosensitive drums 1Y to 1Bk are superimposed and transferred to form an image having a desired color tone.

  When forming an image, first, the surfaces of the photosensitive drums 1Y to 1Bk are uniformly charged by the chargers 2Y to 2Bk. Thereafter, laser beams LY, LM, LC, and LBk deflected and scanned based on image information are emitted from the optical scanning device S according to the present embodiment (details will be described later) onto the surfaces of the photosensitive drums 1Y to 1Bk. An electrostatic latent image is formed on the surface of the photosensitive drum.

  The photosensitive drums 1Y to 1Bk on which the electrostatic latent images are formed rotate and move, and the electrostatic latent images are yellow and yellow by the developing devices 4Y, 4M, 4C, and 4Bk provided close to the photosensitive drums 1Y to 1Bk. Visualized in magenta, cyan, and black toner images.

  Thereafter, the photosensitive drums 1Y to 1Bk further rotate and move, and the formed toner images of the respective colors are successively superimposed on the transfer belt 8 sandwiched between the transfer rollers 5Y to 5Bk and the nip portions of the photosensitive drums 1Y to 1Bk to electrostatically. Transfer (primary transfer) is performed.

  Toner remaining on the surface of the photosensitive drums 1Y to 1Bk without being electrostatically transferred onto the transfer belt 8 is removed by cleaners 6Y, 6M, 6C, and 6Bk provided for the photosensitive drums 1Y to 1Bk. The photosensitive drums 1Y to 1Bk from which the residual toner has been removed are charged again by the chargers 2Y to 2Bk in order to form the next image.

  A plurality of sheet materials P used as a recording medium are stacked on a feeding tray 41 disposed at the lower part of the main body of the image forming apparatus, and are fed one by one by a feeding roller 42 at the timing of image formation. The

  The fed sheet material P is sequentially fed from the feeding roller 42 to the conveying belt 7, conveyed to the conveying belt 7, and reaches a contact portion (secondary transfer portion) with the transfer belt 8. Then, the multicolor toner image formed on the transfer belt 8 is secondarily transferred onto the sheet material P, and a color image is formed on the sheet material P.

  The sheet material P to which the color image has been transferred is then thermally fixed by the fixing device 45, conveyed by the discharge roller 46, etc., and output outside the image forming apparatus.

(Schematic configuration of the optical scanning device S)
A schematic configuration of an optical scanning device according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a perspective view of an optical scanning device S according to the present embodiment.

  In the optical scanning device S according to the present embodiment, a plurality of optical components (deflection members, imaging members, etc.) are arranged inside an optical box 21 as a casing, and four openings as laser light exits are provided. A lid 22 having the same is attached to the optical box 21. And the inside of the apparatus main body is obstruct | occluded by attaching one dustproof member unit U to two opening parts (a 1st opening part, a 2nd opening part) inside the lid | cover 22. FIG.

  The optical scanning device S includes light sources 50a, 50b, 50c, and 50d of laser light emitted to the surfaces (scanned surfaces) of the photosensitive drums 1Y to 1Bk provided outside the apparatus main body. Laser light emitted from the light sources 50 a to 50 d is deflected by deflectors (deflecting members) 19 and 20.

In the present embodiment, the laser light emitted from the light sources 50 a and 50 b is deflected by the deflector 19, and the laser light emitted from the light sources 50 c and 50 d is deflected by the deflector 20.

  The deflectors 19 and 20 are provided with rotary polygon mirrors 17 and 18 that are rotationally driven. When the laser light is deflected based on the image information, the laser light is incident on different surfaces of the rotary polygon mirrors 17 and 18, and the incident laser light is deflected and scanned in different directions.

  The four laser beams scanned by the rotary polygon mirrors 17 and 18 are imaged on the photosensitive drums 1Y to 1Bk as follows.

  First, the laser light deflected and scanned by the rotary polygon mirrors 17 and 18 is transmitted through the first scanning lenses (imaging members) 13a, 13b, 13c, and 13d. Then, the direction is changed by folding mirrors (deflection members) 14a, 14b, 14c, and 14d that are arranged at the same pitch as the photosensitive drums 1Y to 1Bk and inclined by approximately 45 ° with respect to the incident light.

  The laser light whose direction has been changed by the folding mirrors 14a to 14d is transmitted through the second scanning lenses 15a, 15b, 15c and 15d as the final imaging member located on the most downstream side on the optical path, and the optical scanning device S. It is injected from the opening of the lid 22. Then, an image is formed on the surfaces of the photosensitive drums 1Y to 1Bk.

  The light sources 50a to 50d, the deflectors 19 and 20, the first scanning lenses 13a to 13d, the folding mirrors 14a to 14d, and the second scanning lenses 15a to 15d are held in the optical box 21 with high accuracy. In the present embodiment, the optical box 21 is molded from resin.

  In addition, the second scanning lenses 15a to 15d adjust the positions in the directions of arrows A and B shown in FIG. 1, for example, in order to reduce the scanning line deviation (registration deviation) between the colors. The position of the scanning line is adjusted. The second scanning lenses 15a to 15d whose positions have been adjusted are fixed to the lens fixing portions 21a, 21b, 21c, and 21d of the optical box 21 with an adhesive or the like.

(About the sealing structure of the optical scanning device S)
The structure for closing the optical scanning device S according to the present embodiment will be described with reference to FIGS. 1 and 3 to 5.

  In the present embodiment, the dust-proof member unit U is attached to the inside of the lid 22 of the optical scanning device S, and the lid 22 to which the dust-proof member unit U is attached is attached to the optical box 21 to close the inside of the apparatus main body.

  As shown in FIG. 1, one dustproof member unit U is provided for two openings (first opening and second opening) among the four openings formed in the lid 22. That is, a total of two dustproof member units U are provided in the optical scanning device S according to the present embodiment.

  In addition, when attaching the cover 22, it attaches to the optical box 21 from the direction substantially parallel to the emission direction of the laser beam that has passed through the second scanning lenses 15a to 15d, and is fixed by a fixing means such as a screw or snap fit. Hereinafter, the lid 22 and the dustproof member unit U will be described.

  As shown in FIG. 4, dust-proof member accommodating portions 23 a to 23 d having a convex shape in the laser beam emission direction are formed on the lid 22. Each of the dust-proof member accommodating portions 23a to 23d has substantially the same shape as the dust-proof members 31a to 31d of the dust-proof member unit U described later, and accommodates these dust-proof members 31.

  FIG. 3 is a diagram showing the structure of the dustproof member unit U (the two dustproof member units U in the present embodiment have the same configuration, and only one dustproof member unit U will be described).

  The dustproof member unit U is composed of one sheet member 30 and two dustproof members (a first dustproof member 31a and a second dustproof member 31b). The sheet member 30 is made of a PET sheet having a thickness of about 0.2 mm, and the first dustproof member 31a and the second dustproof member 31b are made of a soft material such as soft urethane foam. That is, in the present embodiment, the sheet material 30 is formed of a material having higher bending strength than the dustproof member.

  The first dust-proof member 31a and the second dust-proof member 31b are provided with openings 35a and 35b through which laser light passes, and the sheet member 30 has openings 30a at positions corresponding to these openings. , 30b. Here, the opening of the sheet member 30 is formed to be a larger opening than the opening of the dust-proof member.

  The respective dustproof members are fixed to the sheet member 30 by the double-sided tape 32 in the regions 36 a and 36 b around the openings 30 a and 30 b of the sheet member 30. The sheet member 30 is provided with a round hole 30 c and a long hole 30 d that serve as a positioning reference for the lid 22. Further, a fixing tape 33 serving as a fixing means for the lid 22 is attached to the sheet member 30 between the opening 30a and the opening 30b.

  FIG. 4 is a diagram illustrating a state in which the dust-proof member unit U is attached to the inside of the lid 22.

  The lid 22 is provided with openings 22a to 22d at four locations corresponding to the second scanning lenses 15a to 15d, respectively, and a portion including the openings 22a to 22d has a dustproof member accommodating portion 23a. To 23d are formed. Here, the openings 22a and 22b are referred to as a first opening 22a and a second opening 22b, and the dust-proof member accommodating portions 23a and 23b are referred to as a first dust-proof member accommodating portion 23a and a second dust-proof member accommodating portion 23b. Give an explanation.

  A positioning pin 28c for positioning the dustproof member unit U is formed between the first opening 22a and the second opening 22b (the same applies between the opening 22c and the opening 22d).

  The dust-proof member unit U is positioned relative to the lid 22 by inserting the positioning pins 28c into the round holes 30c and the long holes 30d provided in the sheet member 30, and the first opening 22a and the first It is fixed between the two openings 22b.

  At this time, the first dustproof member 31a and the second dustproof member 31b are accommodated in the first dustproof member accommodating portion 23a and the second dustproof member accommodating portion 23b of the lid 22.

  Then, the optical box 21 is closed by fixing the lid 22 to which the two dustproof member units U are attached to the optical box 21 with fixing means such as screws, and the optical scanning device S is completed.

  FIG. 5 is a schematic configuration diagram in a cross section of the optical scanning device S according to the present embodiment, and a state in which the inside of the device main body is closed will be described.

The widths d1 of the openings 30a to 30d of the sheet member 30 are formed to be about several mm larger than the width d of the second scanning lenses 15a to 15d. Also, dustproof members 31a-3
The width d2 of each of the opening portions 35a to 35d of 1d is set to be about several mm smaller than the width d of the scanning lens. That is, the dimensional relationship is d2 <d <d1.

  Therefore, as shown in FIG. 5, the opening of the first dustproof member 31a and the second dustproof member 31b comes into contact with the second scanning lenses 15a and 15b so that the opening is scanned by the second sheet. The lens 15a, 15b is closed. Further, the first dustproof member 31a and the second dustproof member 31b may be slightly crushed by being sandwiched between the second scanning lenses 15a and 15b and the lid 22.

Therefore, without using a means such as a dust-proof glass that could cause of deterioration of the optical characteristics, dusts floating in the outside of the optical scanning device S is, the second sheet of the scanning lens 15a, 15b, 15c, the optical scanning from the surrounding 15d It is possible to prevent the inside of the device S from entering.

  Further, the sheet member 30 made of a material having a higher bending strength than the dust-proof member 31 does not contact the second scanning lenses 15a to 15d, and only the soft dust-proof member 31 is the second sheet. It contacts the scanning lenses 15a to 15d.

  Therefore, it is possible to prevent a large stress from being applied to the scanning lenses 15a to 15d whose positions have already been adjusted, and the scanning lines adjusted by adjusting the positions of the scanning lenses 15a to 15d vary due to the influence of the dustproof member unit U. The possibility can be reduced.

  Further, in the optical scanning device S according to the present embodiment, the dustproof member unit U unitized as described above is fixed to the lid 22, and the dustproof member is formed in a plurality of openings by one dustproof member unit U. Can be arranged.

  Therefore, compared with the conventional configuration in which the dustproof member itself is fixed to the lid, the mounting workability of attaching the dustproof member to the plurality of openings can be significantly improved.

  Further, since the dust-proof member 31 is fixed to the sheet member 30 made of a material having higher rigidity than the dust-proof member, it is necessary to enlarge the dust-proof member 31 in order to improve the assembling workability of the dust-proof member 31. There is no increase in the size of the optical scanning device.

  A fixing tape for fixing the dustproof member unit U to the lid 22 is affixed to a sheet member 30 having bending strength. Therefore, even if it is necessary to attach and detach the dustproof member unit U in the manufacturing process, the dustproof member 31 having low bending strength is not damaged when the dustproof member unit U is removed. Therefore, in this embodiment, an optical scanning device with excellent recyclability can be provided.

  As described above, the academic scanning device S according to the present embodiment first attaches the lid 22 to which the dustproof member unit U is attached to the optical box 21. The dust-proof member unit U includes a plurality of dust-proof members 31 and a highly rigid sheet member 30, and the dust-proof member 31 is attached to the sheet member 30. A low-rigidity (soft) dust-proof member 31 is in contact with the scanning lenses 15a to 15d as final imaging means located on the most downstream side in the optical path.

  In the present embodiment, the dust-proof member accommodating portion is provided on the lid 22, but the configuration of the optical scanning device according to the present invention is not limited to this. That is, even when using a lid on which no dustproof member accommodating portion is formed, it is possible to apply the dustproof member unit U described above, and therefore it is possible to achieve the same effects as the present embodiment. is there.

  Therefore, according to the optical scanning device of the present invention, it is possible to provide an optical scanning device that is low in cost, excellent in assembly workability, small in size, and excellent in dustproof performance.

Schematic configuration diagram of an optical scanning device according to the present embodiment Schematic configuration diagram of an image forming apparatus in the present embodiment Schematic configuration diagram of a dustproof member unit in the present embodiment Attachment diagram of the dustproof member unit to the lid in the present embodiment Schematic configuration diagram in cross section of the optical scanning device according to the present embodiment

Explanation of symbols

15 Second scanning lens (imaging member)
21 Optical Box 22 Lid 30 Sheet Member 31 Dustproof Member S Optical Scanning Device U Dustproof Member Unit

Claims (2)

A light source that emits laser light;
A deflecting member for deflecting the laser light emitted from the light source;
An imaging member for imaging a laser beam emitted from the light source;
An optical box for holding the light source, the deflection member, and the imaging member;
A lid of the optical box;
With
In an optical scanning device in which laser light is emitted from a plurality of openings formed in the lid to a scanned surface outside the apparatus main body, and the scanned surface is deflected and scanned.
The dustproof member unit dusts from the openings prevents from entering the inside of the apparatus main body, on the inner side of the lid, the first opening of the lid, one for two openings of the second opening is provided,
The dustproof member unit is
A first dustproof member having an opening having an opening width of d2, a second dustproof member,
The first dustproof member and the second dustproof member are attached, and an opening having an opening width d1 is formed at a position corresponding to the opening provided in each of the first dustproof member and the second dustproof member, and the dustproof One sheet member formed of a material having higher bending strength than the member;
D2 <d1, and
The opening of the first dustproof member and the opening of the second dustproof member are positioned so as to face the first opening and the second opening formed in the lid, and the first opening and the second opening And the sheet member is fixed between
The peripheral edge of the opening of the first dustproof member and the peripheral edge of the opening of the second dustproof member are
Among the imaging members, the first dust-proof member is located at the most downstream position on the optical path and is in contact with the first and second imaging members facing the first opening and the second opening. Part, the opening of the second dust-proof member is blocked by the first imaging member, the second imaging member,
Furthermore, the first dust-proof member and the second dust-proof member abut on the lid,
An optical scanning apparatus characterized in that the inside of the apparatus main body can be closed. The lid has
A first dustproof member, a first dustproof member accommodating portion that accommodates the second dustproof member, and a second dustproof member accommodating portion are provided in a portion including the first opening and the second opening,
The first dustproof member accommodating portion and the second dustproof member accommodating portion have a convex shape in a direction in which laser light is emitted, and are substantially the same shape as the first dustproof member and the second dustproof member. The optical scanning device according to claim 1.

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