JPH0519200A - Rotary polygon mirror - Google Patents

Abstract

PURPOSE:To decrease working labor and time for the surface of a reflection mirror and to reduce cost by attaching a sheet by which a surface side is finished as a mirror surface to the respective surfaces of the peripheral surface of a rotary polygon mirror substrate whose shape is polygonal so that the reflection mirror surface may be provided. CONSTITUTION:This rotary polygon mirror 1 is constituted of the rotary polygon mirror substrate 2 which is made of synthetic resin to be thick and in a polygonal shape by injection molding and a sheet 3 which is attached all over the peripheral surface of the substrate 2. The surface side of the sheet 3 is finished to be the mirror surface and reflection mirror surfaces 4 are formed on the respective surfaces in a state where the back surface side thereof is attached all over the peripheral surface of the substrate 2. Since the sheet 3 which has flexibility and whose surface is finished to be the mirror surface has only to be attached all over the respective surfaces of the peripheral surface of the substrate 2, it is unnecessary to directly perform mirror finishing work to the substrate 2. The substrate 2 is made of the synthetic resin by injection, so that cutting work which is performed to a material such as metallic material is unnecessitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary polygon mirror, which is used in a laser printer, for example, which deflects an incident beam by unidirectionally and reflects it, so-called polygon mirror.

[0002]

2. Description of the Related Art Recently, for example, when printing a print signal stored in a floppy disk on an actual paper surface,
Laser printers are widely used because they produce extremely clear prints at extremely high speeds.

A rotary polygon mirror K, which is a so-called polygon mirror, as shown in FIG. 4, is provided here. The rotary polygon mirror K is fitted into a rotary shaft (not shown) connected to a rotary drive source at its center.

The rotating polygon mirror K is formed as a reflecting mirror surface a by cutting, for example, a thick aluminum plate or glass plate into a regular polyhedron parallel to the rotation axis, and finishing each surface of the regular polygon. It was done.

A laser beam is always radiated from a constant portion on the reflecting mirror surfaces a of the rotary polygon mirror K which are rotationally driven at a constant speed. The laser beam incident on the reflecting mirror surface a is deflected as the rotary polygon mirror K rotates and the reflection angle gradually changes.

That is, on one reflecting mirror surface a, the angle of the reflected beam with respect to the incident beam gradually increases from the portion on the incident start side (Sakai or ridgeline) to the portion on the incident end side (boundary or ridgeline). When the rotating polygon mirror K rotates and the next reflecting mirror surface a receives the laser beam and reflects it, the angle of the reflected beam with respect to the incident beam becomes the original small angle again, and gradually increases with rotation. Become big.

After all, since the rotary polygon mirror K rotates in one direction, the incident laser beam is deflected once when one reflecting mirror surface a passes, and the polarized beam is regenerated at the moment when the next reflecting mirror surface a comes. Return to the incident position of. Such one-way deflection (scanning) is most suitable for the above laser printer, which requires high-speed deflection in one direction repeatedly at a constant speed.

[0008]

The reflecting mirror surface a of the rotary polygon mirror K must accurately reflect the laser beam as it is. Conventionally, high precision mirror finishing is performed on each of the peripheral surfaces by means such as ultra-precision diamond cutting. Therefore, it is very troublesome and causes a high cost. The invention of the invention has been filed for the purpose of reducing the cost by changing the above-mentioned precision cutting process to another means that does not require much labor.

For example, in Japanese Unexamined Patent Publication No. 63-15213, a rotary polygon mirror substrate made of synthetic resin having a reflecting mirror surface having a surface roughness of 0.5 μRmax or less is molded, and the reflecting mirror surface is coated with a metal thin film. A rotating polygon mirror is disclosed.

Further, for example, Japanese Patent Laid-Open No. 1-231014
In the publication, a mirror-finished glass plate is used as a reflector.
There is disclosed a rotary polygon mirror which is disposed at a predetermined position in a mold cavity, and a so-called insert molding is performed by injecting a synthetic resin material into the mold.

However, the former Japanese Patent Laid-Open No. 63-15213
The one disclosed in the publication does not require complicated machining for the rotating polygon mirror substrate, and enables injection molding of the rotating polygon mirror substrate, while ultra-precision machining the portion corresponding to the reflecting mirror surface of the injection molding die. , It is necessary to make a mirror finish. The metal thin film covering the reflecting mirror surface is preferably 1 μm, preferably 0.1 μm.
It is necessary to form a uniform and extremely thin film having a thickness of μ or less, and it is impossible to reduce the labor.

Also in the latter Japanese Patent Laid-Open No. 1-231014, it is not necessary to directly process the reflecting mirror surface of the rotating polygon mirror substrate, but one surface of the glass plate needs to be mirror-finished before insert molding. is there.

Moreover, when the number of reflecting mirror surfaces increases, it becomes necessary to prepare a larger number of glass plates having a smaller area and perform all mirror finishing. When arranging these at a predetermined position of the mold, it is necessary to make an accurate arrangement so that the synthetic resin does not leak from the abutting ends of each other, and it is also possible to reduce labor by blocking the weeding. It is impossible.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a rotary polygon mirror which is particularly useful for reducing the cost for reducing the cost of the reflecting mirror surface. is there.

[0015]

In order to achieve the above object, the first invention is a regular polygonal shape, which receives and sequentially reflects a beam on a reflecting mirror surface formed on each circumferential surface thereof, In a rotary polygon mirror that repeatedly deflects in one direction, a thick polygonal rotary polygon mirror base and a sheet attached to each peripheral surface of the rotary polygon mirror base and having its surface side mirror-finished It is a rotating polygon mirror characterized by consisting of and.

In a second aspect of the present invention, the rotary polygon mirror substrate is molded from a synthetic resin material by injection molding, and the sheet is
2. The rotary polygon mirror according to claim 1, wherein the rotary polygon mirror is a metal sheet whose surface is mirror-finished, and is adhered to each of the peripheral surfaces of the rotary polygon mirror base.

According to a third aspect of the present invention, the rotary polygon mirror substrate is molded from a synthetic resin material by injection molding, and the sheet is
The rotary polygonal mirror according to claim 1, wherein the rotary polygonal mirror is a resin sheet whose surface is mirror-finished, and is adhered to each of the peripheral surfaces of the rotary polygonal mirror base.

According to a fourth aspect of the present invention, the rotary polygon mirror substrate is molded from a synthetic resin material by injection molding, and the sheet is
The rotary polygon mirror according to claim 1, wherein the rotary polygon mirror base is insert-molded on each surface of the peripheral surface.

[0019]

[Function] A sheet having flexibility and having a mirror-finished surface is simply attached to each surface of the peripheral surface of the rotary polygon mirror base, and direct mirror-finishing of the rotary polygon mirror base is unnecessary. Is.

The rotary polygon mirror substrate is obtained by injection molding from a synthetic resin material, and does not require cutting such as a metal material. As the sheet, a sheet having a mirror-finished surface such as a metal sheet or a resin sheet can be used. By insert-molding the sheet on the rotating polygon mirror substrate, the labor can be further reduced.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a rotary polygon mirror 1 which is a completed polygon mirror. The rotary polygon mirror 1 is made of a synthetic resin material, is thick, and has a regular polygonal shape (here, a regular hexagon) that is injection-molded into a rotary polygonal mirror substrate 2 and an entire peripheral surface of the rotary polygonal mirror substrate 2. And the sheet 3 that is attached.

The front surface side of the sheet 3 is mirror-finished, and the rear surface side thereof is attached to the entire peripheral surface of the rotary polygon mirror base 2 to form reflecting mirror surfaces 4 ... Become.

A pivot hole 5 is provided at the center of the rotary polygon mirror base 2, and is fitted to a rotary shaft (not shown) in a state of being incorporated in an actual device such as a laser printer.
It is designed to be integrally rotated.

The sheet 3 is a metal sheet 3A made of aluminum, gold, copper or the like, or a resin sheet 3B made of acrylic or PET.

In the case of the metal sheet 3A, the one whose surface (one surface) side is mirror-finished in advance is used. Then, as shown in FIG. 2, the back surface (other surface) is adhered to the peripheral surface of the rotating polygon mirror base 2 with an adhesive such as an epoxy resin. The mirror-finished surface of the metal sheet 3A remains as the reflecting mirror surface 4.

In the case of the resin sheet 3B, the one whose surface (one surface) side is previously vapor-deposited with, for example, SiO ₂ , Au, or is mirror-finished by plating is used. Then, as shown in FIG. 2, the back surface (other surface) is bonded to the entire surface of the rotary polygon mirror base 2 with an adhesive material such as epoxy resin. The mirror-finished surface of the resin sheet 3B remains as the reflecting mirror surface 4.

Again, as shown in FIG. 1, in any case,
The mirror-finished surface of the sheet 3 is exposed on each of the peripheral surfaces of the rotary polygon mirror base 2, and these form the reflection mirror surfaces 4 ...

Since the rotary polygon mirror substrate 2 is an injection-molded product, its manufacturing speed is extremely high, it is suitable for mass production, and it is possible to maintain a high precision of dividing each peripheral surface. At the same time, the smoothness of each of the peripheral surfaces can be maintained at a high level, so that no sagging occurs when the sheet 3 is attached.

It is needless to say that the accuracy of attachment of the sheet 3 to the rotary polygonal mirror substrate 2 is maintained, but the accuracy of each reflecting mirror surface 4 can be easily adjusted as compared with the conventional mirror finishing. Can be secured.

In the above-mentioned embodiment, the continuous sheet 3 is attached over the entire circumference of the rotary polygon mirror base body 2, but the present invention is not limited to this, and each of the peripheral surfaces is attached. It is also possible to form a sheet piece having a shape area adapted to the above and attach it to each.

Further, in the above embodiment, the metal sheet 3A or the resin sheet 3B forming the reflecting mirror surface 4 is adhered to each circumferential surface of the injection-molded rotating polygon mirror base body 2, but the invention is not limited to this. For example, as shown in FIG. 3, the sheet 3 is previously arranged at a predetermined position in the cavity 11 of the mold 10, and later, the synthetic resin material is injected to fix the rotary polygon mirror substrate 2 to the rotary polygon mirror substrate 2. You may shape.

That is, the sheet 3 is insert-molded on the rotary polygon mirror substrate 2, and the bonding step using the adhesive as in the above embodiment is not required, and the rotary polygon mirror can be easily obtained in a shorter time. . In addition, various modifications can be made without departing from the scope of the present invention.

[0034]

As described above, according to the present invention, a sheet having a mirror-finished surface is attached to each of the peripheral surfaces of a polygonal polygonal mirror body to form a polygonal mirror having a reflecting mirror surface. As a result, it is possible to reduce the manufacturing cost, especially for the reflecting mirror surface, and it is possible to reduce the cost.

[Brief description of drawings]

FIG. 1 is a perspective view of a rotary polygon mirror showing an embodiment of the present invention.

FIG. 2 is a perspective view of the same embodiment during manufacturing of the rotary polygon mirror.

FIG. 3 is a perspective view showing another embodiment during manufacturing of the rotary polygon mirror.

FIG. 4 is a view for explaining the action of a rotary polygon mirror.

[Explanation of symbols]

2 ... Rotating polygon mirror substrate, 3 ... Sheet, 3A ... Metal sheet,
3B ... Resin sheet, 4 ... Reflective mirror surface, 10 ... Mold.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuyuki Matsuda             8th Shinsugita Town, Isogo Ward, Yokohama City, Kanagawa Prefecture             Ceremony company Toshiba Yokohama office

Claims (4)

[Claims] 1. A rotary polygonal mirror which is a regular polygonal shape and which receives and reflects a beam on a reflecting mirror surface formed on each circumferential surface thereof, and deflects the beam repeatedly in one direction. A rotary polygon mirror comprising: a rotary polygon mirror base body formed into a sheet; and a sheet attached to each circumferential surface of the rotary polygon mirror base body and having its surface side mirror-finished. 2. The rotary polygon mirror base is molded from a synthetic resin material by injection molding, and the sheet is a metal sheet whose surface is mirror-finished. The rotating polygon mirror according to claim 1, wherein the polygon mirror is adhered. 3. The rotary polygon mirror substrate is molded from a synthetic resin material by injection molding, and the sheet is a resin sheet whose surface is mirror-finished. The rotating polygon mirror according to claim 1, wherein the polygon mirror is adhered. 4. The rotary polygon mirror base body is formed by injection molding from a synthetic resin material, and the sheet is insert-molded on each side surface of the rotary polygon mirror base body. Rotating polygon mirror.