JP2003156705A - Optical scanner, image writing device, image forming device and image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical scanner, an image writing device and an image reader which are made very accurate by an optical element supporting member having light and simple structure, having high rigidity and capable of restraining vibration caused by impact. SOLUTION: Bending parts 41C are provided at both ends of plate material 41A constituting a supporting member 41 for supporting an optical element, and a vibration preventing member 42 is press-fit in a recessed part formed by the bending part 41C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning device for scanning with a light beam, an image writing device for writing an image with a light beam, an image reading device and an image forming device.

[0002]

2. Description of the Related Art An optical scanning device and an image writing device for scanning and exposing a photosensitive member by using a light beam composed of a laser are incorporated in a copying machine, a printer, a facsimile and the like.

In such an optical scanning device, a light beam is polarized by the light deflecting means to scan the object to be scanned in the main scanning direction, and by moving the object to be scanned in the sub scanning direction, the object to be scanned is scanned. The surface is uniformly scanned.

Surface scanning in image formation is 400 to 20.
Since it is a high-resolution scan such as 00 dpi (dots per 24.5 mm), vibration and deformation are extremely suppressed in the optical scanning device for image formation.

FIG. 1 shows a support structure for an optical element in a conventional optical scanning device. Reference numeral 40 is a unit frame body of the optical unit in which the optical elements are housed, and 41 is a support member for supporting the unit frame body 40. The support member 41 is composed of a plate-shaped plate member 41A having hook-shaped bent portions at both ends, and three reinforcing members 41B having a U-shaped cross section fixed to the plate member 41A by spot welding. Three reinforcing members 41
B has an effect of increasing the rigidity of the support member 41 and an effect of suppressing vibration due to impact.

[0006]

In the conventional supporting member 41 shown in FIG. 1, in order to ensure rigidity, it is necessary to increase the thickness of the plate member 41A or the reinforcing member 41B, and there is a problem that the mass increases accordingly. Also, there is a problem that vibration cannot be suppressed sufficiently. In order to suppress the vibration, measures such as fixing the vibration preventing member to the supporting member 41 with an adhesive are taken, but there is a problem that it becomes difficult to disassemble and it becomes difficult to use as a recycled component. .

Further, since the composite part as shown in FIG. 1 is manufactured through an assembling process, there is a problem that the cost becomes high.

Such a problem exists not only in an optical scanning device such as an image writing device but also in an image reading device which requires high accuracy.

An object of the present invention is to solve the above problems in the conventional optical scanning device and image reading device.

[0010]

The above-mentioned objects of the present invention are as follows.
It is achieved by the following invention.

1. In a scanning optical device having an optical element that constitutes a scanning optical system and a supporting member that supports the optical element, the supporting member is made of a plate material having a U-shaped cross section at least at one end. An optical scanning device characterized by.

2. 2. The optical scanning device according to the above 1, wherein a vibration prevention member is press-fitted into a concave portion formed by the bent portion.

3. 3. The optical scanning device according to 1 or 2 above, wherein the optical element constitutes a laser light source and the scanning optical system that scans an object to be scanned with a light beam from the laser light source.

4. 3. The optical scanning device according to 2, wherein the vibration prevention member is press-fitted into a plurality of portions of the bent portion.

5. 5. The optical scanning device according to any one of 1 to 4 above, wherein the bent portions are provided at both end portions.

6. 6. The optical scanning device according to any one of 1 to 5 above, wherein a hole into which a component other than the optical scanning device is inserted is provided in the plate material.

7. In an image writing apparatus having a light source for exposing a photosensitive member, an optical element forming a scanning optical system, and a supporting member for supporting the optical element, the supporting member has a U-shaped cross section at least at one end. An image writing device comprising a plate material having a bent portion.

8. 8. The image writing device as described in 7 above, wherein a vibration preventing member is press-fitted into a concave portion formed by the bent portion.

9. 9. The image writing device as described in 8 above, wherein the vibration preventing member is press-fitted into a plurality of portions of the bent portion.

10. 10. The image writing device according to any one of 7 to 9 above, wherein the bent portions are provided at both end portions.

11. 7 to 1 characterized in that the plate member is provided with a hole into which a part other than the image writing device is inserted.
The image writing device according to any one of 0.

12. 12. A photoconductor, the image writing device according to any one of 7 to 11 for writing an image on the photoconductor, a developing device for developing a latent image formed by writing by the image writing device, and the developing device. An image forming apparatus comprising: a transfer device that transfers the toner image formed by the method to recording paper; and a fixing device that fixes the toner image on the recording paper.

13. 12. A photoconductor, the image writing device according to any one of 7 to 11 for writing an image on the photoconductor, a developing device for developing a latent image formed by writing by the image writing device, and an intermediate transfer member. A primary transfer device for transferring the toner image formed by the developing device onto the intermediate transfer member, a secondary transfer device for transferring the toner image on the intermediate transfer member onto recording paper, and fixing the toner image on the recording paper. An image forming apparatus having a fixing device.

14. In an image reading apparatus having an image pickup device, a lens for forming an image on the image pickup device, and a support member for supporting the image pickup device and the lens, the support member has a U-shaped cross section at least at one end. An image reading apparatus comprising a plate material having a bent portion.

15. The vibration preventing member is press-fitted into a concave portion formed by the bent portion.
The image reading apparatus described in 1.

16. 16. The image reading device as described in 15 above, wherein the vibration preventing member is press-fitted into a plurality of portions of the bent portion.

17. 17. The image reading device described in any one of 14 to 16 above, wherein the bent portions are provided at both side end portions.

18. An image forming apparatus, comprising: the image reading device according to any one of 14 to 17; and an image forming unit that forms an image based on image data generated by the image reading device.

[0029]

FIG. 2 is a diagram showing an optical scanning device, an image writing device and an image forming apparatus according to an embodiment of the present invention.

As shown in FIG. 2, the image forming apparatus is called a tandem type color image forming apparatus, and includes an automatic document feeder 30, an image reading apparatus 50, an image writing apparatus 3Y,
3M, 3C, 3K, photoconductors 1Y, 1M, 1C, 1K, charging devices 2Y, 2M, 2C, 2K, developing devices 4Y, 4M,
4C, 4K, fixing device 24, belt-shaped intermediate transfer member 6,
It has a sheet feeding and conveying means.

The document automatic conveying means 30 is a means for automatically conveying a double-sided document. The image reading device 50 is a device in which image information is read by a movable optical system, and the contents of a large number of documents d fed from the document table are reflected by three movable mirrors 60C, and a condensing lens. The image is read by the image pickup device 60A composed of CCD by the image pickup device 60B.

Image forming section 1 for forming a yellow image
0Y has a charging device 2Y, an image writing device 3Y, a developing device 4Y, and a cleaning device 8Y which are arranged around a photoconductor 1Y as an image forming body. The image forming unit 10M that forms a magenta image includes a photoconductor 1 as an image forming body.
M, a charging device 2M, an image writing device 3M, a developing device 4M, and a cleaning device 8M. The image forming unit 10C that forms a cyan image includes a photoconductor 1 as an image forming body.
C, a charging device 2C, an image writing device 3C, a developing device 4C and a cleaning device 8C. The image forming unit 10K that forms a black image includes a photoconductor 1K as an image forming body, a charging device 2K, an image writing device 3K, a developing device 4K, and a cleaning device 8K. Charging device 2Y and image writing device 3Y, charging device 2M and image writing device 3M, charging device 2
C, the image writing device 3C, the charging device 2K, and the image writing device 3K form a latent image forming unit.

The intermediate transfer member 6 is an endless belt,
It is stretched by a plurality of rollers and is rotatably supported.

Image forming units 10Y, 10M, 10C and 1
The images of each color formed from 0K are transferred onto the rotating intermediate transfer member 6 by transfer devices 7Y, 7M, and 7C as primary transfer devices.
And 7K are sequentially transferred (primary transfer) to form a combined color image. Paper feed cassettes 20A, 20
The recording paper PE accommodated in B and 20C is fed by the paper feeding means 21.
Paper is fed by A, 21B, and 21C, and is conveyed through a conveying system 22 to a transfer device 7A as a secondary transfer device, and a color image is transferred onto the recording paper PE (secondary transfer). The recording paper PE on which the color image has been transferred is fixed by the fixing device 24, sandwiched by the paper discharge rollers 25, and placed on the paper discharge tray 26 outside the machine.

On the other hand, after the color image is transferred onto the recording paper PE by the transfer device 7A, the intermediate transfer body 6 from which the recording paper PE is separated is cleaned by the cleaning device 8A.

5Y, 5M, 5C and 5K are the developing device 4
It is a toner replenishing means for replenishing Y, 4M, 4C, and 4K with new toner.

The photoelectrically converted analog signal is subjected to analog processing, A / D conversion, shading correction, image compression processing, etc., in an image processing unit (not shown), and then to the image writing devices 3Y, 3M, 3C and 3K. Send a signal.

FIG. 3 shows a writing optical system. Reference numeral 31 is a semiconductor laser serving as a laser light source, and the light beam L emitted from the semiconductor laser 31 is formed into a scanning light beam by the optical elements 32 to 36 and is incident on the photoconductor 1 serving as a scanned body.

Reference numeral 32 is a collimator lens, 33 is a first cylindrical lens, 34 is a rotary polygon mirror, 35 is an fθ lens, and 36 is a second cylindrical lens. Main scanning is performed by high-speed rotation of the rotary polygon mirror 34 and sub-scanning is performed by moving the photoconductor 1 in a direction orthogonal to the paper surface, and the photoconductor 1 is uniformly surface-scanned.

FIG. 4 is an exploded perspective view of an optical scanning device as the image writing device 3. The scanning optical system shown in FIG. 3 is housed in the unit frame body 40 of the writing unit, and a light beam is emitted from the emission window 40A. The unit frame body 40, which is the frame body of the writing unit, is screwed to the support member 41 through the mounting hole 41E of the support member 41.

The support member 41 is made of a plate material 41A having a bent portion 41C having a U-shaped cross section at both ends, and a vibration preventing member 42 such as rubber or plastic is press-fitted into a groove formed in the bent portion 41C. It The plate member 41A is preferably made of metal, and the vibration preventing member 42 is formed of the plate member 4A.
It is made of a material having a vibration characteristic different from that of 1A. Further, since the vibration prevention member 42 is fixed to the groove of the bent portion 41C by press fitting, it is desirable that it be made of an elastic material. In this respect, rubber is used for the vibration preventing member 42, but plastic or the like may be used as long as it has elasticity enough to allow press fitting. In the illustrated example, four vibration prevention members 42 are attached, but one or more vibration prevention members 42 can be provided as needed.

Reference numeral 41D is a hole. The hole 41D reduces the weight of the image writing device 3, and the parts other than the image writing device 3 are arranged in the hole 41D, thereby downsizing the entire image forming apparatus. To be done.

FIG. 5 is an acceleration diagram in which the vibration characteristic of the image writing device 3 is measured by an accelerometer, and FIG. 5A shows the acceleration when a support member without the vibration prevention member 42 is used. FIG. 5B shows the acceleration when the support member 41 shown in FIG. 4 to which the vibration prevention member 42 is attached is used.

As is apparent from the figure, by attaching the vibration preventing member, the vibration characteristic of the image writing device 3 is remarkably improved, and the blurring of the light beam is prevented during the writing of the image so that the image of high quality can be obtained. Can be formed.

FIG. 6 shows a reading unit of the image reading apparatus according to the embodiment of the present invention. The reading unit 60 is a part of the fixed optical system of the image reading device 50, and has an image pickup element 60A composed of a CCD line sensor and a condenser lens 60B for forming an image on the image pickup element 60A. The support member 62 that supports the image sensor 60A and the condenser lens 60B is the image sensor 60.
A plate member 62A to which a support plate 63 that supports A and the condenser lens 60B is fixed is provided, and a bent portion 62B having a U-shaped cross section is provided at both ends of the plate member 62A.
Four vibration preventing members 62C are press-fitted into B. The unit frame 61 of the reading unit is fixed to the support member 62 with screws.

The vibration preventing member 62C includes a vibration preventing member 42.
Similarly to the above, it is made of a material having a vibration characteristic different from that of the plate material 62A such as rubber or plastic.

Although the image forming apparatus using the intermediate transfer member has been described above, the present invention is not limited to the photosensitive member, the image writing device,
It has a developing device, a transfer device, and a fixing device, and can be used in an image forming apparatus that forms an image by an image forming process in which a toner image formed on a photoconductor is transferred from a photoconductor to recording paper and fixed. Of course.

[0048]

The effects of the above 1, 3, 5, 6, 7, 10-14,
According to the seventeenth or eighteenth invention, since the optical element is supported by the supporting member that is lightweight and has high rigidity, it is possible to perform high-precision scanning without deterioration of image quality due to blurring of the light beam. Therefore, it becomes possible to form a high quality image by writing using the optical scanning device according to the present invention.

According to the invention of 2, 4, 8, 9, 15 or 16, vibration due to an external force or an impact generated in the apparatus is highly suppressed, so that the disturbance of scanning due to the vibration is satisfactorily prevented and the image writing is performed. It is possible to effectively prevent the deterioration of image quality due to scanning and the deterioration of reading accuracy during image reading. Further, since the vibration prevention member is attached by press fitting, the assembly time of the apparatus can be shortened, and it can be easily removed from the support member when disassembling the apparatus, which is easy to disassemble and can be disassembled in a short time. , An image writing device, an image reading device, or an image forming device is realized.

[Brief description of drawings]

FIG. 1 is a diagram showing a support structure of a conventional optical scanning device.

FIG. 2 is a diagram showing an optical scanning device, an image writing device, and an image forming device according to an embodiment of the present invention.

FIG. 3 is a diagram showing a writing optical system.

FIG. 4 is an exploded perspective view of the optical scanning device.

FIG. 5 is an acceleration diagram.

FIG. 6 is a diagram showing a reading unit.

[Explanation of symbols]

3, 3Y, 3M, 3C, 3K image writing device 40, 61 unit frame 41, 62 support members 41A, 62A plate material 41B, reinforcing member 41C, 62B Bent section 42, 62C Vibration prevention member

Claims (18)

[Claims] 1. A scanning optical device having an optical element forming a scanning optical system and a supporting member supporting the optical element, wherein the supporting member has a bent portion having a U-shaped cross section at least at one end. An optical scanning device comprising a plate material having the optical scanning device. 2. The optical scanning device according to claim 1, wherein a vibration preventing member is press-fitted into a concave portion formed by the bent portion. 3. The optical scanning according to claim 1, wherein the optical element constitutes a laser light source and the scanning optical system that scans the object to be scanned with a light beam from the laser light source. apparatus. 4. The optical scanning device according to claim 2, wherein the vibration preventing member is press-fitted into a plurality of portions of the bent portion. 5. The optical scanning device according to claim 1, wherein the bent portions are provided at both end portions. 6. The optical scanning device according to claim 1, wherein the plate member is provided with a hole into which a component other than the optical scanning device is inserted. 7. An image writing apparatus having a light source for exposing a photoreceptor, an optical element forming a scanning optical system, and a supporting member for supporting the optical element, wherein the supporting member has a cross section at least at one end. An image writing device comprising a plate material having a U-shaped bent portion. 8. The image writing device according to claim 7, wherein a vibration preventing member is press-fitted into a concave portion formed by the bent portion. 9. The image writing device according to claim 8, wherein the vibration preventing member is press-fitted into a plurality of portions of the bent portion. 10. The image writing device according to claim 7, wherein the bent portions are provided at both end portions. 11. The plate member is provided with a hole into which a part other than the image writing device is inserted.
The image writing device according to any one of 0. 12. A photoconductor, an image writing device according to claim 7, wherein an image is written on the photoconductor, and a latent image formed by writing by the image writing device is developed. An image forming apparatus comprising: a developing device; a transfer device for transferring a toner image formed by the developing device onto a recording sheet; and a fixing device for fixing the toner image on the recording sheet. 13. A photoconductor, an image writing apparatus according to claim 7, wherein an image is written on the photoconductor, and a latent image formed by writing by the image writing apparatus is developed. A developing device, an intermediate transfer member, a primary transfer device that transfers the toner image formed by the developing device to the intermediate transfer member, a secondary transfer device that transfers the toner image on the intermediate transfer member to recording paper, and a recording paper. An image forming apparatus having a fixing device for fixing the toner image of 1. 14. An image reading apparatus having an image sensor, a lens for forming an image on the image sensor, and a support member for supporting the image sensor and the lens, wherein the support member has a cross section at at least one end. An image reading apparatus comprising: a plate member having a U-shaped bent portion. 15. The anti-vibration member is press-fitted into a concave portion formed by the bent portion.
The image reading apparatus described in 1. 16. The image reading apparatus according to claim 15, wherein the vibration prevention member is press-fitted into a plurality of portions of the bent portion. 17. The image reading device according to claim 14, wherein the bent portions are provided at both end portions. 18. An image forming device, comprising: the image reading device according to claim 14; and an image forming unit that forms an image based on image data generated by the image reading device. apparatus.