JPH06148550A - Optical scanning device - Google Patents

Abstract

PURPOSE:To prevent the attachment of dust on a polygon mirror by applying adhesive agent partly or wholly on an inner surface of an optical box containing the polygon mirror and an inner surface of a cover body covering the optical box. CONSTITUTION:Liquid binding agent 22 is applied to part of all of an inner surface of an optical box 11 and an inner surface of a cover body 12. A pressure sensitive adhesive double coated tape, for example, may be applied instead. In such a constitution, dust invading into the optical box 11 is scattered by air currents by the rotation of a polygon mirror 15 from a space between the optical box 11 and the cover body 12 or an aperture 11c to be attached to the binding agent 22. As a result, the quantity of floating dust in the optical box 11 can be reduced.

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 used in a laser beam printer or the like, and more particularly to an optical scanning device for preventing contamination of a polygon mirror which deflects and scans a laser beam.

[0002]

2. Description of the Related Art In a conventional optical scanning device, a laser oscillator 2 for emitting a laser beam and a polygon mirror 3 for deflecting and scanning the emitted laser beam are deflected in an optical box 1 as shown in FIG. An imaging lens 4 for forming an image of the laser beam, a folding mirror 5 for reflecting the formed laser beam to the outside of the optical box 1, and the folded laser beam outside the optical box 1. A photosensitive drum 7 for forming an image is provided below.
Further, on a part of the peripheral edge of the optical box 1, a locking claw 1a for locking the hook 7a of the cover 7 as shown in FIG.
Screw hole 1b for screwing a screw (not shown) through the hole 7b
And an opening 1c for passing the laser beam to the outside of the optical box 1.

On the other hand, the polygon mirror 3 housed in the optical box 1 is mounted on a flange 9 of a motor 8 and fixed by a leaf spring 10 as shown in FIG.

[0004]

However, in the above-mentioned conventional example, fine dust enters the optical box 1 through the gap between the optical box 1 and the cover 7 or the opening 1c, and the polygon mirror 3,
There is a problem that it adheres to the image forming lens 4, the folding mirror 5, etc., especially on the surface of the polygon mirror 3 to reduce the reflectance and deteriorate the image output. Further, when replacing the polygon mirror 3 to which dust is attached, a highly skilled person uses a tool or a measuring instrument to replace the optical scanning device for each unit in a complete dust-proof chamber to prevent dust from entering. The troublesome work is required.

An object of the present invention is to solve the above-mentioned problems and to provide an optical scanning device which reduces the adhesion of dust to a polygon mirror.

Another object of the present invention is to provide an optical scanning device which can easily replace a polygon mirror to which dust is attached.

[0007]

An optical scanning device according to a first invention for achieving the above object is an optical scanning device for deflecting and scanning a laser beam with a polygon mirror,
An adhesive material is applied to a part or all of the inner surface of the optical box that houses the polygon mirror and the inner surface of the lid that covers the optical box.

The optical scanning device according to the second invention is an optical scanning device for deflecting and scanning a laser beam with a polygon mirror, and a cap having light transmissivity is detachably attached to the polygon mirror to accommodate the polygon mirror. The lid body that covers the optical box is provided with a hole for replacing the cap and an opening / closing lid that covers the hole.

[0009]

In the optical scanning device according to the first aspect of the present invention having the above-mentioned structure, the adhesive is applied to a part or all of the inner surface of the optical box and the inner surface of the lid, and the dust in the optical box is rotated by the polygon mirror. Scatter with and adhere to the adhesive.

In the optical scanning device according to the second aspect of the present invention, the cap is detachably attached to the polygon mirror, the cover body is provided with a hole for replacing the cap, and an opening / closing cover for covering the hole. Open and replace the cap from the hole.

[0011]

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 perspective view of a first embodiment showing a state in which a lid 12 is opened from an optical box 11 as shown by an arrow. A laser oscillator 13 for emitting a laser beam is provided on the side of the optical box 11, and the emitted laser beam is parallel to the inside of the optical box 11 in the traveling direction of the laser beam emitted from the laser oscillator 13. There is provided a cylindrical lens 14 for performing the scanning, and a motor 16 having a polygon mirror 15 for deflecting and scanning the parallelized laser beam. Inside the optical box 11 in the traveling direction of the laser beam deflected by the polygon mirror 15, an image forming lens 17 for forming an image of this laser beam and the formed optical beam of the optical box 11 are formed.
A folding mirror 18 for reflecting the light to the outside is provided, and a photosensitive drum 19 for forming an image of the laser beam folded by the folding mirror 18 is provided below the optical box 11. Further, a BD sensor unit 20 and a BD mirror unit 21 are provided inside the optical box 11.

On the other hand, the optical box 11 has a locking claw 11a for mounting the lid 12, a screw hole 11b for screwing a screw (not shown), and a laser beam reflected by the folding mirror 18 to the optical box 11. Opening 1 for passing to the outside
1c and are provided. Further, the locking claw 1 is provided on the lid 12.
A hook 12a that locks to 1a and a mounting hole 12b for penetrating a screw are provided.

Further, a liquid adhesive 22 such as olivine is applied to a part or all of the inner surfaces of the optical box 11 and the lid 12 with a brush or the like. Although olivine was used as the adhesive 22 in the embodiment, for example, a double-sided adhesive tape may be attached instead.

With this structure, the dust that has entered the optical box 11 through the gap between the optical box 11 and the lid 12 or the opening 11c is scattered by the wind flow of the polygon mirror 15 and the adhesive 22 The amount of suspended dust is reduced.

FIG. 2 is a sectional view of the second embodiment, in which a polygonal mirror 15 is covered with an annular cap 23 made of a synthetic resin material having a light transmitting property. As shown in FIG. 3, the cap 23 has at least one locking claw 23a that locks with the peripheral edge of the lower surface of the polygon mirror 15.
The cap 23 is provided at more than one place, and the cap 23 is the polygon mirror 1.
It is designed so that it will not fall off due to an external force such as shock or vibration after it is mounted on 5. The polygon mirror 15 is mounted on the flange 24 of the motor 16 and is pressed and fixed by a leaf spring 25.

As shown in FIG. 4, the lid body 24a of the lid 24 is provided with a hole 24b used when replacing the cap 23 and an opening / closing lid 24c for covering the hole 24b. The lid 24c is patched to the lid body 24a.

With such a structure, in the cap 23, the lid 24 is removed from the optical box 11, or the open / close lid 24c of the lid 24 fixed to the optical box 11 is opened. , Attached to the polygon mirror 15. Therefore, since the polygon mirror 15 is covered with the cap 23, dust and the like are prevented from adhering thereto. Further, the cap 23 can be easily replaced through the hole 24b by opening the opening / closing lid 24c.

FIG. 5 is a sectional view of the optical scanning device of the third embodiment, which is provided with a sensor 25 and a detection circuit 26 for measuring the amount of light applied to the photosensitive drum 19.

As shown in FIG. 6, the detection circuit 26 displays the alarm signal S as an electric sound or on the operation panel when the level B of the light amount S detected by the sensor 25 with respect to the time T is equal to or lower than the slice level A. By doing so, the necessity of replacement of the cap 23 is instructed. In other words, if dust adheres to the cap 23 and exceeds a certain amount,
Since the reflection characteristic of the polygon mirror 15 is deteriorated, an alarm signal is output.

[0020]

As described above, in the optical scanning device according to the first aspect of the present invention, since the dust in the optical box is scattered by the rotation of the polygon mirror and adheres to the adhesive, the amount of dust in the optical box is reduced. The dirt on the polygon mirror is reduced.

In the optical scanning device according to the second aspect of the present invention, since the polygon mirror is detachably attached to the polygon mirror, dust is not directly attached to the polygon mirror. Further, since the lid is provided with the hole for replacing the cap and the opening / closing lid for covering the hole, it is not necessary to remove the lid from the optical box when replacing the cap, and the workability is improved. .

[Brief description of drawings]

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

FIG. 2 is a sectional view of a second embodiment.

FIG. 3 is a perspective view of a cap.

FIG. 4 is a perspective view of a lid body.

FIG. 5 is a configuration diagram of a third embodiment.

FIG. 6 is a graph showing the relationship between the amount of light and time.

FIG. 7 is a perspective view of a conventional example.

FIG. 8 is a perspective view of a lid of a conventional example.

FIG. 9 is a cross-sectional view of a conventional rotating device.

[Explanation of symbols]

 11 Optical Box 12, 24 Lid 15 Polygon Mirror 22 Adhesive 23 Cap 24c Open / Close Lid 25 Sensor 26 Light Quantity Detection Circuit

Claims (2)

[Claims] 1. An optical scanning device for deflecting and scanning a laser beam with a polygon mirror, wherein an adhesive material is applied to a part or all of an inner surface of an optical box accommodating the polygon mirror and an inner surface of a lid covering the optical box. An optical scanning device characterized by the above. 2. An optical scanning device for deflecting and scanning a laser beam with a polygon mirror, wherein a cap having optical transparency is removably attached to the polygon mirror, and a lid for covering an optical box containing the polygon mirror is attached to the lid. An optical scanning device comprising a hole and an opening / closing lid for covering the hole for replacing the cap.