JP2524907Y2 - Optical system mirror anti-vibration structure of image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vibration damping structure for suppressing bending vibration of an optical system mirror of an image forming apparatus.

[Conventional technology]

2. Description of the Related Art An image forming apparatus such as a copying machine scans a document by reciprocating an optical system mirror and exposes a photosensitive drum to form an electrostatic latent image.

In the meantime, when the optical system mirror continuously scans, a shock generated at the time of return every time scanning is completed may cause a bending vibration and an image (electrostatic latent image) on the photosensitive drum may be blurred. Further, this bending vibration is more likely to occur in an image forming apparatus that performs scanning at a higher speed.

As a countermeasure, it is conceivable to increase the rigidity of the mirror itself by increasing the thickness of the mirror or attaching a reinforcing member to the non-reflective surface (back surface) side of the mirror. Scanning becomes difficult,
The overload causes a rise in the temperature of the drive motor for the optical system mirror. Therefore, to ensure high-speed scanning,
It is necessary to increase the power of the driving motor.

On the other hand, as disclosed in Japanese Patent Application Laid-Open No. 60-244921, there has been proposed a mirror in which the vibration of the mirror is suppressed by superposing a buffer member and a metal member on the non-reflection surface side of the mirror.

[Problems to be solved by the invention]

However, in the anti-vibration structure disclosed in Japanese Patent Application Laid-Open No. 60-244921, the vibration of the mirror can be reduced by the cushioning member, but not only does the weight of the optical system mirror increase, but also the shock at the time of return causes a shock. It is not possible to sufficiently suppress the large amplitude flexural vibration that occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an optical system mirror anti-vibration structure of an image forming apparatus capable of suppressing bending vibration of a mirror caused by a return shock.

[Means for solving the problem]

In order to achieve the above object, the present invention is based on the idea that after the reflecting surface is directed in the backward movement direction, and the optical system mirror having a long length in a direction orthogonal to the backward movement direction moves forward to the return position,
In an image forming apparatus that performs exposure scanning of a document by moving backward, the image forming apparatus is capable of moving forward and backward, is provided on the back side of the reflection surface, and supports the mirror on both sides in the long direction. The supporting surface of the scale and the regulating member fixed to the supporting frame and located at a substantially intermediate position in the longitudinal direction of the mirror and abutting against the back surface of the reflecting surface are turned in the reflecting direction, and this After the optical system mirror having a long length in the direction perpendicular to the moving direction moves forward to the return position, the image forming apparatus performs exposure scanning of the original by moving backward, and is provided so as to be able to move forward and backward. A support frame for supporting the mirror in the elongate direction on the reversing direction side, and being fixed to the support frame, at a substantially intermediate position in the elongate direction of the mirror, and abutting against the back surface of the reflection surface. And a regulating piece member.

[Operation] At the time of return (when scanning at the return position is stopped and when starting at the return position) each time exposure scanning is completed, a shock due to the inertia of the optical system mirror causes the optical system mirror to bend in the forward direction,
As it vibrates in the reciprocating direction as it is, especially because the support frame supports the optical system mirror on both sides of the long length of the optical system mirror, the above bending becomes maximum near the middle of the long direction, but the above configuration In the image forming apparatus, the optical system mirror anti-vibration structure, that is, the regulating piece member abutting on the back surface of the reflection surface, that is, from the forward movement direction, is provided at a substantially intermediate position in the longitudinal direction, so that the structure is simple. In spite of this, the vibration in the forward movement direction, which occurs first due to the shock at the time of return, is restricted, and the vibration in the backward movement direction is also suppressed.

〔Example〕

FIG. 3 is a configuration diagram of an embodiment of an image forming apparatus provided with an optical system mirror anti-vibration structure according to the present invention.

The image forming apparatus has a contact glass 22 and a document holder 23 on an upper surface thereof, and includes an optical system L and an image forming unit P inside.

The optical system L includes a halogen lamp 14, a reflector 15, and a mirror.
The first moving body 1, the first mirror 3 and the second mirror 4 comprising 16
Moving body 2, fixed mirror 24 and lens unit 25
It is composed of

As shown in FIG. 4, the first and second moving bodies 1 and 2 are slidably supported at their front and rear ends on cylindrical guide rails 17 and 18, respectively, and include a driving motor 19 and driving mechanisms 20 and 21. With this, it is made to reciprocate along the guide rails 17 and 18. The light from the halogen lamp 14 (not shown in FIG. 4 for convenience) is reflected on the original on the contact glass 22 by the reciprocating movement of the first and second moving bodies 1 and 2, and the mirror 16 and the mirror 16 After being guided to the lens unit 25 through the mirrors 3 and 4, the photosensitive drum 26 described below is exposed through the fixed mirror 24.

The image forming means P includes a photosensitive drum 26, a charging device 27, a blank clamp 28, a developing device 29, a transfer device 30, a separating device.
31 and a cleaning device 32, etc.
Is transferred to a sheet of paper. further,
As the paper feed mechanism, a plurality of paper feed cassettes 33a, 33b, paper feed rollers 34a, 34b, pairs of transport rollers 35, 36, and pairs of registration rollers 37 are arranged in this order from the upstream in the feeding direction. Is supplied to the photosensitive drum 26 to perform transfer. A transport belt 38, a fixing device 39, a discharge roller 40, a paper discharge tray 41, and the like are provided as a fixing and discharging mechanism for the sheet after the transfer.

Next, the anti-vibration structure provided on the first moving body 1 will be described with reference to FIGS. 1 and 2. FIG. The mirror
Numerals 16 are fixed to the support frame 6 at both ends in the longitudinal direction by, for example, three-point support.

The regulating member 5 is made of a rigid body such as a metal and has a predetermined width and a substantially L-shaped cross section. In addition, the regulating member 5 has a long hole.
Screws 9 and 8 pass through these elongated holes 9 and 10 and are fixed to a mounting portion 11 protruding toward a mirror 16 at a substantially intermediate portion in the longitudinal direction of the support frame 6. ing. Further, the end surface 12 of the regulating member 5 is inclined in accordance with the inclination of the mirror 16, and the end surface 12 is configured to come into contact with the non-reflection surface (back surface) 13 of the mirror 16.

That is, when continuous scanning is performed, the mirror 16 is bent backward (to the right in FIG. 1) due to a shock (inertial force) generated at the time of return each time the scanning is completed, that is, at the time of scanning stop and at the time of restarting scanning. I do. This deflection amplitude is mirror 16
Becomes larger in the middle of the longitudinal direction. Therefore, by causing the regulating member 5 to abut on the rear surface of the mirror 16 and the intermediate portion in the longitudinal direction, it is possible to effectively regulate the bending vibration of the mirror 16 that occurs at the time of the return.

Note that a method of contacting the regulating member 5 with the mirror 16 will be described. That is, the regulating member 5 is brought into contact with the mirror 16 with a certain force using a spring or the like, and the screws 7 and 8 are tightened in this state. For this reason, the strength of the force applied to the mirror 16 can be restricted to an appropriate level by the regulating member 5, and the flatness of the mirror 16 can be maintained.

The number of the attachment portions 11 may be two or more as long as they are near the middle of the support frame 6 in the longitudinal direction. Further, in the above description,
Although the regulating member 5 is provided on the first moving body 1, the first and second mirrors 3 and 4 and the fixed mirror 24 of the second moving body 2 are also provided with the regulating member in the same manner, and the same effect as the mirror 16 described above is provided. You can also get

[Effect of the invention]

According to the present invention, it is possible to restrict the bending vibration of the mirror due to the shock at the return every time the scanning is completed, without substantially increasing the weight, by simply providing the restricting piece member that only comes into contact with the image. Blur can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along the line II of FIG. 2 showing an optical system mirror anti-vibration structure according to the present invention. FIG. 2 is a plan view showing one embodiment of the optical system mirror anti-vibration structure according to the present invention. FIG. 3 is a block diagram of an embodiment of an image forming apparatus using the vibration-proof structure according to the present invention, and FIG. 4 is a perspective view of an optical system of the image forming apparatus using the vibration-proof structure according to the present invention. . 1 1st moving body, 2 2nd moving body, 5 ... regulating member, 6 ... support frame, 7, 8 ... screw, 9, 10 ... elongated hole, 11 ...
... Mounting part, 16 ... Mirror, L ... Optical system.

Claims (1)

(57) [Scope of request for utility model registration] An exposure scan of a document is performed by moving a reflecting surface in a backward direction, moving an optical system mirror having a length in a direction orthogonal to the backward direction to a return position, and then returning. In the image forming apparatus to be performed, a forward and backward movement is possible, provided on the back side of the reflection surface, a long support frame that supports the mirror on both sides in the long direction, and the support frame An optical system anti-vibration structure for an image forming apparatus, comprising: a regulating member fixed at a substantially intermediate position in a longitudinal direction of the mirror and abutting on a back surface of the reflection surface.