JPH0634902A - Scanning optical device - Google Patents

Abstract

PURPOSE:To stably hold an optical component such as a lens which is fixed by an elastic member even if the strong force due to a fall, etc., is received. CONSTITUTION:Elastic members 21 and 22 which fix optical components such as a spherical lens 6, a toric lens 7 and a reflecting mirror 10 are molded integrally with an optical box 1 and deformation restraint members 24, 25a, and 25b which requlate the deformation of those elastic members 21 and 22 are molded integrally with a lid body 23. The deformation requlating members 24, 25a, and 25b are so arranged that they are in the vicinity of the elastic members 21 and 22 when the optical box 1 is covered with the lid body 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning optical device used in laser beam printers, laser facsimiles and the like.

[0002]

2. Description of the Related Art In a scanning optical device used in a laser beam printer, a laser facsimile, etc.,
The light beam deflected and scanned by the deflector scans the photoconductor to form an electrostatic latent image. This electrostatic latent image is visualized as a toner image by a developing device, and this toner image is transferred to a recording paper,
After that, the fixing device heats and fixes the toner on the recording paper to print.

FIG. 4 is a plan view showing the structure of a scanning optical device used in a conventional laser beam printer.
FIG. 5 is a sectional view at the center of the optical axis. The scanning optical device is housed in an optical box 1 and comprises a collimator lens 3 for collimating the light flux generated from the semiconductor laser light source 2, a cylindrical lens 4 for condensing the parallel light flux from the collimator lens 3 on a line, and a cylindrical lens 4. It is composed of a rotary polygon mirror 5 having a deflecting / reflecting surface 5a arranged in the vicinity of a line image of a light beam formed by being condensed, and an fθ lens 8 in which a spherical lens 6 and a toric lens 7 are combined.

The spherical lens 6 and the toric lens 7 are elastically fixed to the optical box 1 by using a spring member 9.
One end of the spring member 9 has a shape for pressing the spherical lens 6 or the toric lens 7 in the mounting reference plane direction on the optical box 1, and is fixed on the optical box 1 by screwing the mounting portion of the spring member 9. ing. The fixing is to prevent the lens and the reflecting mirror from being stressed and damaged due to the difference in linear expansion coefficient due to heat.

The light beam deflected and reflected by the deflecting / reflecting surface 5a enters the reflecting mirror 10 through the fθ lens 8 and is reflected, and passes through the opening of the optical box 1 as shown in FIG. Irradiate. The reflecting mirror 10 is also elastically fixed to the optical box 1 by the spring member 12 in the same manner as the spring member 9. The fθ lens 8 is designed so that the light beam reflected by the deflecting / reflecting surface 5a becomes spot light on the photoconductor 11 and the scanning speed of the spot light is kept constant. The rotation of the rotary polygon mirror 5 causes the photoconductor 11 to perform main scanning with a light beam, and the photoconductor 11 is driven to rotate around the cylinder to perform sub-scanning.

[0006]

However, due to the recent cost reduction, productivity improvement, etc., the spring member 9,
There have been demands for alternative mounting methods to the Twelve. Based on these requirements, a snap-fit mounting method that uses the elastic force of the mold member has recently been known as an alternative, but this snap-fit fixing causes excessive force to act on the fixed part due to falling or the like. In that case, the fixed claw may escape, and there is a risk of problems such as falling of parts and permanent deformation of the claw.

An object of the present invention is to provide a scanning optical device capable of reliably and stably fixing optical components such as a lens by an extremely simple means.

[0008]

A scanning optical device according to the present invention for achieving the above object is a scanning optical device which utilizes an elastic member for fixing an optical component such as a lens. A deformation regulating means for regulating the deformation is provided in the vicinity.

[0009]

In the scanning optical device having the above-described structure, the deformation of the elastic member that fixes the lens and the like is restricted, so that the lens and the like are stably held even when a strong force acts due to a drop or the like.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in FIGS. FIG. 1 is a plan view of a first embodiment of the scanning optical device, and FIG. 2 is a sectional view. Since the basic structure of the device is the same as that of the conventional device described above with reference to FIGS. 4 and 5, members having the same functions are designated by the same reference numerals and the description thereof will be omitted. Eight elastic members 21 that fix the spherical lens 6 and the toric lens 7 respectively are integrally formed by rising from the optical box 1 at a position where the optical path is not shielded, and have a claw portion at the tip. . The spherical lens 6 is pushed downward from above the optical box 1 at the position of the elastic member 21, the elastic member 21 is deformed in the escape direction, and when further pushed to reach a predetermined position, the claw portion at the tip of the elastic member 21 is pushed. It is fixed by locking. Toric lens 7
Is fixed in the same way.

Since the reflecting mirror 10 is inclined with respect to the optical box 1 by an angle θ, the elastic member 22 for fixing the reflecting mirror 10 is also formed in a direction perpendicular to the mounting surface of the reflecting mirror 10.
The reflecting mirror 10 is fixed by being pushed in parallel to the elastic member 22 from the upper right of FIG.

As means for restricting the deformation of these elastic members 21, 22, the deformation restricting members 24, 2 are provided on the lid 23.
5a and 25b are molded respectively, and the optical box 1
When the lid 23 is attached to the deformation restricting members 24, the deformation restricting members 25a and 25b are located near the elastic member 21, respectively.
Is located near the elastic member 22.

When acceleration is applied to the optical box 1 by being dropped or the like, the spherical lens 6 may exert a force for bending the elastic member 21 in the opening direction. At this time, the deformation regulating member 24 acts to prevent the deformation of the elastic member 21. This also applies to the other deformation regulating members 25a and 25b.

FIG. 3 shows a second embodiment, (a) is a cross-sectional view of the main part in the optical axis direction, and (b) is a cross-sectional view of the main part in the direction perpendicular to the optical axis. Here, an example is shown in which the leaf spring 26 is used as an elastic member that fixes the reflecting mirror 10. In the leaf spring 26,
A locking portion 26a and a reflector holding portion 26b are formed, and a locking hole 1a is formed in the optical box 1. The leaf spring 26 puts the reflecting mirror 10 at a predetermined position of the optical box 1,
It is fixed by inserting the locking portion 26a into the locking hole 1a.

A deformation regulating member 27 is molded on the lid body 23 as a means for regulating the deformation of the leaf spring 26. When the lid body 23 is attached to the optical box 1, the deformation regulating member 27 is engaged. By being inserted into the stop hole 1a,
The locking portion 26a is prevented from coming off the optical box 1.

Although the above embodiments have been described by taking the scanning optical device used in the laser beam printer as an example, the present invention is applied to various other optical devices for fixing lenses and other parts by elastic members. It goes without saying that you can do it. Further, the deformation regulating member is not necessarily provided on the lid, and may be provided on the optical box 1 itself, for example.

[0017]

As described above, in the scanning optical device according to the present invention, since the deformation regulating member is provided in the vicinity of the elastic member fixing the optical component such as the lens, an excessive load such as a drop is applied. It is possible to prevent the optical components such as the lens from falling off even if the lens is damaged. In addition, it is possible to attach a lens or the like at a low cost and with good workability and with certainty by an extremely simple means.

[Brief description of drawings]

FIG. 1 is a plan view of a first embodiment.

FIG. 2 is a sectional view.

FIG. 3 is a cross-sectional view of essential parts of a second embodiment.

FIG. 4 is a plan view of a conventional example.

FIG. 5 is a sectional view.

[Explanation of symbols]

 1 Optical Box 2 Semiconductor Laser Light Source 5 Rotating Polygonal Mirror 6 Spherical Lens 7 Toric Lens 10 Reflecting Mirrors 21, 22 Elastic Member 23 Lid 24, 25a, 25b, 27 Restricting Member 26 Leaf Spring

Claims (2)

[Claims] 1. A scanning optical device that uses an elastic member to fix an optical component such as a lens, wherein a deformation restricting means that restricts deformation of the elastic member is provided in the vicinity of the elastic member. . 2. The scanning optical device according to claim 1, wherein the regulating means is provided on a lid of an optical box.