JPH0742744Y2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to an image forming apparatus such as a printer or a digital copying machine which forms an image by forming a light beam on a photoconductor.

[Conventional technology]

FIG. 5 is a conceptual diagram showing an overall configuration of an image forming apparatus such as a laser printer, FIG. 6 is a perspective view showing a conventional example of an optical frame, and FIG. 7 is a sectional view showing an example of an attached state of the optical frame. . In the figure, 1 is a light source, 2 is a deflector, 3 and 4 are image forming lens systems, 5 is an optical frame, 6 is a mounting member, 7 is a photoconductor, 8 is a fulcrum shaft, 9 is a basic frame, and 11 is a subframe. , 12 is a paper feeding mechanism, and 13 is a paper ejection tray.

In an image forming apparatus such as a laser printer, generally, a light beam is repeatedly scanned in the main scanning direction by a deflecting unit such as a rotary polygon mirror, and the photoconductor is moved in the sub-scanning direction at an exposure position to thereby make the photoconductor uniform. An image corresponding to an image signal is formed by drawing a large number of scanning lines with a pitch.

In addition, especially in a small-sized image forming apparatus, a basic frame that can be pivotally divided around a predetermined fulcrum axis for maintenance and inspection of peripheral devices of the photoconductor, removal of transfer material jammed during transfer material transfer, etc. The main body is divided into subframes.

As shown in FIG. 5, the image forming apparatus main body is configured to be divided into the upper side (sub-frame) and the lower side (basic frame), and the free end side is lifted. FIG. 6 shows a perspective view.

In FIG. 5, the main body is divided into a basic frame 9 and a sub-frame 11, and the sub-frame 11 can be opened and closed by driving around a fulcrum shaft 8. Then, a paper feed mechanism 12 and a paper discharge tray 13 are attached to the basic frame 9,
The optical frame 5 and the photoconductor 7 are attached to the sub-frame 11.

In general, the optical frame 5 includes a light source 1 as shown in FIG.
A deflection device 2 for scanning the light beam emitted from the light source 1, a lens system 3, 4 for forming an image of the light beam scanned by the deflection device 2, and the like are housed. The optical frame 5 is integrally provided with a rigid attachment member 6, and is attached to the subframe 11 together with the photoconductor 7 or the paper feed mechanism 12
It is fixed to the basic frame 9 directly with screws together with the paper ejection tray 13 and the like.

[Problems to be solved by the invention]

However, since the conventional image forming apparatus is directly fixed with the screws as described above, it has the following drawbacks.

For example, when the optical frame 5 must be attached to the basic frame 9 or the sub-frame 11 in the state originally shown in FIG. 7A, when the basic frame 9 or the sub-frame 11 is deformed, Accordingly, the optical frame 5 is also deformed as shown in FIG. 7 (b), and the relative positions of the lens system 4, the light source 1, the deflecting device 2, and the like change, so that the initial performance cannot be maintained.

If the accuracy of the optical frame receiving portion 10 (see FIG. 4 (b)) of the basic frame 9 or the sub-frame 11 is poor, the optical frame 5 is deformed by the fixing and the same trouble as that occurs.

The present invention solves the above problems, and minimizes the influence on the optical frame due to the deformation of the basic frame or the sub-frame or the inaccuracy of the optical frame mounting portion, and the above-mentioned adverse conditions. It is an object of the present invention to provide an image forming apparatus that can maintain the initial performance even under the conditions.

[Means for solving problems]

Therefore, the present invention uses an elastic member as a mounting member for each fixing portion in an image forming apparatus including a scanning optical device in which a light source, a deflection unit, an imaging lens system, and a mirror are assembled in one optical frame. The optical frame is fixed in combination with a restriction member that restricts deformation of the elastic member. The frame configuration of the entire image forming apparatus is divided into a basic frame and a sub-frame supported by the basic frame so as to be opened and closed by being driven around a predetermined axis,
In the scanning optical device, as shown in FIGS. 1 and 2, the light source 1, the deflecting device 2, the imaging lens systems 3 and 4, the mirror 8 and the like are assembled into one optical frame.

[Action]

Conventionally, the mounting member 6 is an optical frame 5 as shown in FIG.
While the image forming apparatus of the present invention is an integral rigid body, the mounting member 6 is formed of an elastic member as shown in FIGS. 1 and 3. Therefore, even if the basic frame 9 or the sub-frame 11 is deformed as shown in FIG. 4 or the optical frame receiving portion 10 (see FIG. 4 (b)) is inaccurate, these influences are not affected. 6 disappears because it is deformed and absorbed. As a result, in the image forming apparatus,
The initial performance can be maintained regardless of the accuracy and installation conditions of the basic frame 9 or subframe 11.

〔Example〕

 Hereinafter, embodiments will be described with reference to the drawings.

FIG. 1 is a perspective view of an optical frame of an image forming apparatus according to the present invention, FIG. 2 is a side sectional view, and FIG. 3 is a view for explaining the operation of a mounting member.

In FIG. 1, the mounting member 6 is formed of an elastic member. Except for this mounting member 6, it has the same structure as the optical frame of FIG. 6 described above. In particular, the mounting member 6 is, for example, in the shape of an inverted L as shown in FIG. 3, has a mounting hole for mounting to the basic frame 9 or the sub-frame 11 on the upper surface A, and has a vertical portion C. It is inserted into the fixed groove of the optical frame 5. A claw B is provided in the vertical portion C, and when the claw B is inserted into the fixing groove, the claw B is bitten and fixed in the groove. When the upper surface A of the mounting member 6 is mounted on the basic frame 9 or the sub-frame 11, the mounting member 6 formed of an elastic member has the upper surface A with a restoring force in a vertical (β) direction as shown in FIG. And can be deformed in the twisting direction (α in the drawing).

Therefore, as shown in FIG. 1, mounting members 6 are provided on three sides of the optical frame 5, and when the mounting members 6 are mounted on the basic frame 9 and the sub-frame 11, the optical frame 5 is mounted as shown in FIG. Even if the basic frame 9 is deformed like an arch, this deformation is absorbed by the deformation of the mounting member 6. Therefore, the optical frame 5 is not affected by the deformation of the basic frame 9, and it is possible to prevent the optical paths of the deflecting device 2, the imaging lens systems 3 and 4, and the mirror 8 from being displaced as shown in FIG. The initial properties of the system can be maintained. This is because the mounting member 6 is deformed as shown by the dotted lines (α, β) in FIG. 3 to absorb the deformation of the basic frame 9 and the sub frame 11. In this way, the mounting member 6 is displaced not only in the vertical direction but also in the left and right twisting directions with a restoring force, so that the deformation of the optical frame 5 as shown in FIG. 7B can be prevented. .

4A and 4B are views showing another embodiment of the mounting member of the present invention, wherein FIG. 4A is a perspective view and FIG. 4B is a sectional view taken along line XX. The difference from FIGS. 1 to 3 is that the stopper 6 ′, which is made of one or more elastic bodies or rigid bodies, is placed on the mounting member 6 and is positioned above the optical frame 5 without contacting the optical frame 5. It is the point installed in.

The stopper 6'has a collar 6'-1 with which the upper end of the optical frame 5 abuts when the mounting member 6 is largely displaced, as shown in the sectional view of FIG. 4 (b). The relative movement of the optical frame 5 in the vertical direction due to the elasticity of the mounting member 6 is restricted to a predetermined stroke range by the collar 6'-1.

By doing so, it becomes possible to further protect the mounting member 6 against a shock applied to the optical frame 5. Also, the harder it is to transmit the deformation and inaccuracy of the basic frame 9 to the optical frame 5, the smaller the spring constant of the mounting member 6 must be made. Deformation and damage of the product easily occur. Therefore, by providing a rigid stopper 6 ', the deformation of the mounting member 6 can be limited to the elastic deformation region. Further, by providing the elastic stopper 6 ', this can be used as a non-linear spring whose spring constant changes when the mounting member 6 is constantly deformed.

[Effect of device]

As is clear from the above description, according to the present invention, the optical frame is mounted using the mounting member formed of the elastic member, so that the deformation of the base frame or the sub-frame which is the mounting base does not affect the optical frame. The relative positional relationship among the light source 1, the deflection device 3, the imaging lens system 4, the mirror 8 and the like can be maintained. As a result, the initial performance can be stably exhibited. Further, since the mounting member absorbs the vibration and shock caused by the opening and closing of the subframe, it is possible to prevent the displacement of the mounting position due to the vibration and shock caused by the opening and closing operation of the subframe.

[Brief description of drawings]

FIG. 1 is a perspective view of an optical frame of an image forming apparatus according to the present invention, FIG. 2 is a side sectional view, FIG. 3 is a view for explaining the operation of a mounting member, and FIG. 4 is a mounting member of the present invention. FIG. 5 is a conceptual view showing the overall structure of the image forming apparatus, FIG. 6 is a perspective view showing a conventional example of an optical frame, and FIG. 7 is an example of an attached state of the optical frame. It is sectional drawing shown. 1 ... Light source, 2 ... deflecting device, 3 and 4 ... imaging lens system, 5 ... optical frame, 6 ... mounting member, 7 ... photoreceptor, 8 ... fulcrum shaft, 9 ... basic frame , 11 …… Subframe.

Claims (1)

[Scope of utility model registration request] 1. An image forming apparatus comprising a scanning optical device in which a light source, a deflection means, an imaging lens system and a mirror are assembled in one optical frame, and an elastic member is used as a mounting member for each fixing portion. An image forming apparatus characterized in that an optical frame is fixed in combination with a limiting member for limiting deformation of a member.