JP2002131676A - Writing optical device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a writing optical device which is capable of efficiently cooling a rotary scanner without degrading its soundproof and dustproof performance by assuring the hermeticity of an optical housing for housing the rotary scanner and an image forming device mounted with this device. SOLUTION: The base surface of the optical housing (2) for housing the rotary scanner (1) is provided with an aperture (8) to enable the circulation of air in the optical housing (2), by which the heat generated by driving of the rotary scanner (1) is discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a writing optical device for improving the cooling efficiency of a rotary scanning device in a writing optical device for deflecting and scanning a laser beam using the rotary scanning device. The invention also relates to an image forming apparatus equipped with the writing optical device.

[0002]

2. Description of the Related Art In an image forming apparatus such as a laser beam printer and a laser facsimile, a rotary scanning device is used to deflect and scan a laser beam and write the obtained scanning light on a photosensitive member on a rotating drum. Optical devices are used. In a rotary scanning device including a polygon mirror, it is necessary to take measures against sound of the polygon mirror rotating at high speed and measures against dust of the optical components. For this reason, the rotary scanning device is in a substantially sealed state provided with an external device and a partition. At present, particularly, the speed of the apparatus is required to be increased, and the rotation of the polygon mirror is further increased. Therefore, heat generated from a motor for rotating the polygon mirror causes a rise in temperature around the rotary scanning apparatus. Since the rise in temperature causes a decrease in the optical performance of the surrounding optical components and the rotational performance of the drive motor, various studies have been made on this.

For example, in an optical deflection scanning device disclosed in Japanese Patent Application Laid-Open No. H11-52267, an air path is provided by providing a projection having a space at the bottom of an optical box and closing the opening with a lower lid. The temperature rise inside the optical box is prevented by forming and flowing cold outside air there.
In the deflection scanning device disclosed in Japanese Patent Application Laid-Open No. H11-218717, a bearing of a rotary polygon mirror, a driving IC
From the paper tray can be radiated through a sheet metal cover to an air passage provided in a gap between the sheet discharge tray.

[0004]

However, the above two deflection scanning devices have a problem that cooling efficiency is poor because cooling air flows outside the sealed optical box.

[0005] In view of the above problems, in the present invention, the sealing of the optical housing for accommodating the rotary scanning device is ensured, and the cooling of the rotary scanning device is efficiently performed without lowering the soundproofing and dustproof performance. It is an object of the present invention to provide a writing optical device which can be performed at a high speed and an image forming apparatus equipped with the writing optical device.

[0006]

According to a first aspect of the present invention, there is provided a writing optical apparatus for deflecting and scanning a laser beam using a rotary scanning apparatus. A writing optical device, wherein a cooling opening is provided at the bottom of the housing.
According to a second aspect of the present invention, a bottom plate of the image forming apparatus main body for installing the optical housing is provided by a sheet metal member, and the writing optical device has a cooling opening at the bottom of the optical housing according to the first aspect. The image forming apparatus has a structure in which a projection along the optical housing opening is provided on a bottom plate of the image forming apparatus main body. According to a third aspect of the present invention, in the image forming apparatus of the second aspect, a dustproof member is provided between the optical housing opening and the bottom plate protrusion.

According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects, a heating section of a rotary scanning device housed in the optical housing, and the image forming apparatus main body. Wherein the sheet metal bottom plate is connected with a heat conductive member. According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to fourth aspects, the image forming apparatus has a bottom plate provided with a duct portion connected to the optical housing opening. A forming device.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic sectional view of a storage portion of a rotary scanning device (1) of a writing optical device according to the first aspect of the present invention. In the optical housing (2),
A holding section (5) for positioning and holding a bearing section (4) of the rotary scanning device (1) is provided. The rotary scanning device (1) is housed in a substantially sealed state by an optical housing (2), a cover (3), and a soundproof glass (not shown).

When the rotary scanning device (1) is driven, a driving substrate (6) provided integrally with the rotary scanning device (1).
The electronic components mounted on the device generate heat. In particular, the drive IC (7) and the bearing (4) generate a large amount of heat. Since the rotary scanning device (1) is installed in the optical housing (2) in a hermetically sealed state, heat generated inside hardly escapes to the outside, and the temperature inside the optical housing (2) increases as the driving time becomes longer. Let me do it. The rotary scanning device (1), optical housing (2), and other optical components (not shown) include a drive IC (7) and a bearing unit (4).
, Heat is caused to expand by heat and the optical performance is degraded. If the temperature continues to rise, the rotary scanning device (1) will be damaged.

In the writing optical device according to the present invention, the opening (8) is provided on the bottom surface of the optical housing (2) so that air in the optical housing (2) can circulate. And the rotary scanning device (1)
The heat generated by the drive can be discharged.

FIG. 2 is a schematic sectional view of a writing optical device of the image forming apparatus according to the second aspect of the present invention. A projection (9) is provided on a bottom plate (10) of the image forming apparatus main body made of a sheet metal member along an opening (8) provided at the bottom of the optical housing (2). The heat inside the optical housing (2) is conducted from the protrusion (9) to the bottom plate (10) of the image forming apparatus main body, and the entire bottom plate (10) efficiently radiates heat. Further, by providing the protruding portion (9) on the bottom plate (10) of the image forming apparatus main body, the optical housing (2) for the toner scattered from the photoconductor unit, the developing unit and the like provided near the optical housing (2). It makes it difficult to get inside.

FIG. 3 is a schematic sectional view of a writing optical device of the image forming apparatus according to the third aspect of the present invention. An elastic dustproof member (1) is provided in the opening (8) of the optical housing (2).
2) is provided, and the bottom plate (10) of the image forming apparatus main body is provided.
When the optical housing (2) is set in the optical housing (2), the elastic dustproof member (12) hermetically closes and closes the gap between the opening (8) of the optical housing (2) and the projection (9) of the bottom plate. This prevents entry of scattered toner and the like from the opening (8).

FIG. 4 is a schematic sectional view of a writing optical device of an image forming apparatus according to a fourth aspect of the present invention. The bottom plate (10) of the image forming apparatus main body that supports the optical housing (2) at a predetermined position is made of a heat conductive member such as SECC. The bottom plate (10) of the image forming apparatus main body and the drive IC (7) of the rotary scanning device (1) are connected by a connecting member (13) made of a heat conductive and elastic member.
The heat generated by driving the rotary scanning device (1) receives the bottom plate (1) of the image forming apparatus main body by the connecting member (13) without warming the inside of the optical housing (2).
0), heat can be dissipated using the entire bottom plate (10) of the image forming apparatus main body.

FIG. 5 is a schematic sectional view of a writing optical device of an image forming apparatus according to a fifth aspect of the present invention. An optical housing (2) is provided on the bottom plate (10) of the image forming apparatus main body.
A duct (14) connected to the opening (8) is provided;
Suction fan (15) provided at outlet of duct (14)
As a result, the warmed air inside the optical housing (2) is directly discharged to the outside.

[0015]

As described above, in the writing optical device according to the first aspect, since the cooling opening is provided at the bottom of the optical housing, heat generated by driving the rotary scanning device is discharged. can do. Claim 2
In the image forming apparatus, the bottom plate of the image forming apparatus main body includes:
Since the protrusion is provided along the opening at the bottom of the optical housing, the warmed air inside the optical housing can be more effectively discharged. Further, it is possible to prevent scattered toner and the like from entering the inside of the housing. In the image forming apparatus according to the third aspect, since the dustproof member is provided between the optical housing opening and the bottom plate protrusion, it is possible to effectively prevent the scattering toner and the like from entering through the opening. In the image forming apparatus according to the fourth aspect, since the drive IC of the rotary scanning device, which is a heat source, and the bottom plate of the image forming apparatus main body are connected by a heat conductive member, the bottom plate of the image forming apparatus main body is used as a heat radiating member. It can be used and the generated heat can be efficiently dissipated. In the image forming apparatus according to the fifth aspect, since the duct is provided on the bottom plate of the image forming apparatus main body, the warmed air inside the optical housing can be directly discharged to the outside by the suction fan.

As described above, a writing optical device capable of efficiently cooling a rotary scanning device without deteriorating soundproofing and dustproofing performance by maintaining the airtightness of an optical housing, and an image mounted with the same. It is possible to provide a forming apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a rotary scanning device housing portion of a writing optical device according to the first embodiment of the present invention.

FIG. 2 is a schematic sectional view of a writing optical device of the image forming apparatus according to the second embodiment.

FIG. 3 is a schematic sectional view of a writing optical device of the image forming apparatus according to the third embodiment.

FIG. 4 is a schematic sectional view of a writing optical device of the image forming apparatus according to a fourth aspect of the present invention.

FIG. 5 is a schematic sectional view of a writing optical device of the image forming apparatus according to the invention of claim 5;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 rotary scanning device 2 optical housing 3 cover 4 bearing unit 5 holding unit 6 drive board 7 drive IC 8 opening 9 projecting unit 10 image forming apparatus main body bottom plate 12 dustproof member 13 connecting member 14 duct unit 15 suction fan

Claims (5)

[Claims] 1. A writing optical device for deflecting and scanning a laser beam using a rotary scanning device, wherein a cooling opening is provided at the bottom of an optical housing for housing optical components. 2. The image forming apparatus main body bottom plate for installing the optical housing is provided by a sheet metal member, and the writing optical device has a structure in which a cooling opening is provided at the bottom of the optical housing according to claim 1. An image forming apparatus, wherein a projection along the optical housing opening is provided on a bottom plate of the image forming apparatus main body. 3. The image forming apparatus according to claim 2, wherein a dustproof member is provided between the optical housing opening and the bottom plate protrusion. 4. The image forming apparatus according to claim 1, wherein a heat generating portion of the rotary scanning device housed in the optical housing and a sheet metal bottom plate of the image forming device main body are thermally conducted. An image forming apparatus comprising: an image forming apparatus; 5. The image forming apparatus according to claim 1, further comprising a duct connected to the optical housing opening in the bottom plate of the main body of the image forming apparatus.