JPS63175725A - Rotary disk for reflection type rotary encoder - Google Patents

Abstract

PURPOSE:To eliminate problem points of machining technology and to improve performance as a rotary plate by providing a metallic disk which is formed by a photoelectroforming method, etc., and has a rotary shaft fitting hole in the center part. CONSTITUTION:The rotary disk R of a reflection type rotary encoder is composed of the metallic disk 2. Then a nonreflective material 6 is spread or applied over the top surface of the metallic disk 2 to form a nonreflection part 8. In this case, the nonreflective material is spread or applied on the metallic disk 2 except a thin beltlike body groups 10 without being spread nor applied on the top surfaces of the thin beltlike body group 10 present radially around the fitting hole 4 along the inside of the outer periphery of the metallic disk 2. Then, films are formed of a material with high reflecting ability, e.g. rhodium on the top surfaces of the thin beltlike body group 10, which serves as reflection parts 12. Consequently, the faults of the machining technology as to a conventional rotary disk which uses glass, etc., are eliminated.

Description

[Detailed description of the invention] (b) Industrial application field The present invention relates to a rotating plate for a reflective rotary encoder.

(o) Prior Art Conventionally, this type of rotary plate has been manufactured by depositing a metal with high reflectance on a mirror glass plate, and then forming reflective parts, e.g., strip-like bodies, in a radial pattern on the deposited surface using a method such as photo-etching. Reflective portions arranged in a pattern are formed, and non-reflective portions are formed by printing or the like in areas other than the reflective portions.

After that, attach the encoder's rotating shaft to the center of the radial reflection section.
A hole for attaching the encoder was provided, or the outer circumference of the rotary plate was formed, and the thus completed rotary plate was fitted and fixed to the rotary shaft of the encoder. This type of rotary plate is made of a glass body with a metal-deposited surface serving as a reflective portion and a black printed portion serving as a non-reflective portion.

(c) Problems to be Solved by the Invention Since the rotary plate of the conventional example is formed by processing the entire glass substrate, it has the following problems: A point occurred.

(a) Since the glass plate has thin strip-shaped reflective parts arranged radially, it is important to remember the exact center position of the reflective part when drilling a hole in the center of this reflective part to fit the rotary shaft of the encoder. Providing fitting holes in the glass plate and cutting the glass plate to form the outer circumference of the rotating plate require extremely advanced technology, and careful work is required to obtain the desired glass rotating plate. (b) In order to maintain the strength of the rotating glass plate by inserting it into the rotary shaft of the encoder, form the glass plate to an appropriate thickness. Therefore, the glass rotating plate has a considerable weight, and the moment of inertia during rotation together with the rotating shaft becomes relatively large.

(C) Since a glass body is used for the rotating plate, unnecessary vibrations and collisions occurring during high-speed rotation can cause damage to the glass body, which is dangerous.

The present invention aims to overcome the above-mentioned problems, and below, means and effects for solving the problems will be disclosed.

(b) Means and operation for solving the problem The rotary plate of the reflective rotary encoder of the present invention is composed of a metal circular plate9. The rotating shaft is mounted on a metal disk with a hole, and a non-reflective material on the top surface of the metal disk except for a group of thin strips arranged radially around the mounting hole along the inside circumference of the metal disk. Provided is a rotating plate for a reflective rotary encoder, which has a non-reflective part which is spread or coated by a method such as electrodeposition, and a reflective part which has a material film having high reflectivity formed on the upper surface of the group of narrow strips. . When this rotary plate is mounted on a rotary IH by fitting and fixing it onto a rotating shaft through a hole and rotating in a predetermined direction together with this rotating shaft, laser beams, etc. transmitted from a light emitting element through an optical waveguide, such as an outgoing optical fiber, etc., are transmitted to the rotating plate. The reflected light is guided to the light-receiving element through the return optical fiber ζ, etc., reaches the light-receiving element, and is subjected to photoelectric conversion by the photoelectric conversion means.

(e) Examples The present invention will be described in detail below with reference to the accompanying drawings.

The rotating plate a according to the present invention shown in FIGS. 1A and 1B is made of nickel or the like. A non-reflective portion 8 is formed by spreading or coating a non-reflective material 6 on the upper surface of this metal disk 2 by a technique such as electrodeposition. At this time, the non-reflective material 6 should not be spread or coated on the upper surface of the narrow strip-shaped body group 10 that exists radially along the inner side of the outer periphery of the metal disk 2 with the low alignment hole 4 as the center, that is, the narrow strip-shaped body Metal disk 2 excluding group 10
A non-reflective material is spread or coated on top. Next, by forming a coating 11 on the upper surface of the strip-shaped body group 10 by plating or the like using a material having high reflectivity, such as rhodium, the narrow strip-shaped body group 10 serves as the reflective section 12.

FIG. 2 illustrates another embodiment. The metal disc 14 is formed by a method such as electroforming, similar to the safe disc 2 shown in FIG. 1, and is made of a material having high reflectivity, such as rhodium.

The structure of the non-reflective part 8 is the same as that of the embodiment shown in FIG.
0 serves as the reflecting portion 12 as is without any processing on its upper surface.

In other words, the unprocessed portion of the strip group 10 of the rhodium metal disk 14 constitutes the reflecting section 12 as it is.

FIG. 3 illustrates yet another embodiment. A coating 16 of a highly reflective material such as rhodium is applied by plating or the like on the upper surface of a metal disk 2 made of nickel or the like and manufactured by a method such as photoelectroforming, similar to the metal disk 2 shown in FIG. form. Furthermore, this plating film 1
6, metal discs 2 are arranged radially around the fitting hole 4.
The non-reflective portion 8 is formed by spreading or applying the non-reflective material 6 by a method such as electrodeposition, except for the group of narrow strips 10 disposed inside the outer periphery. The strip group 10 which is not processed by spreading or coating the non-reflective material 6 forms the reflective part 12 as it is.

FIG. 4 is a route map of a rotary encoder employing a rotating plate according to the present invention.

The rotating plate R configured as described above is attached to the rotating shaft 20 and used as a rotating plate of a reflective rotary encoder. A laser beam etc. emitted from the light emitting element 22 passes through an optical waveguide, for example, an outgoing optical fiber 24, and passes through the slit 2 of the fixed plate 28.
Transmits 6. A rotary plate having a reflective part 12 made of a strip-like reflective group 10 on the side where a laser beam or the like is incident in contact with a fixed plate 28 has a rotating shaft 20 fitted and fixed in a fitting hole 4.
and rotate in a predetermined direction. During rotation, when the slit 26 of the fixed plate 28 and any one of the narrow strip reflecting groups 10 of the rotating plate a are synchronized, the laser beam passes through the slit of the fixed plate 28, is reflected by the reflecting part 12 of the rotating plate R, and Further, the light enters the return path optical fibers 30 through the slit 26 of the fixed plate 28, passes through the optical fibers 30, is blown to the light receiving element 32, and is photoelectrically converted by the photoelectric conversion means.

(f) Effects The present invention employs a metal disk manufactured by methods such as photoelectroforming, electrodeposition, and plating.1. Therefore, it overcomes the processing technology problems, inertia, breakage, etc. that are considered to be the defects of conventional rotary plates using glass substrates, and uses a metal disc with high reflective ability as a reflective part. This helps improve performance as a rotating plate.

[Brief explanation of the drawing]

FIG. 1(A) is a plan view of an embodiment of the rotating plate of the reflective rotary encoder according to the present invention, and FIG.
-A cross-sectional view taken along the line X. FIG. 2(A) is a plan view of a rotary plate of an encoder according to another embodiment. Same (B) is Y of same (A)
-A cross-sectional view taken along the line Y. FIG. 3(A) is a plan view of a rotating plate of an encoder according to another embodiment. The same (B) is the same (A)
A cross-sectional view along the line Z-Z of. Figure 4 is a route map of a rotary encoder that uses a rotating plate. R is a rotating plate, 2 is a metal disk, and 4 is a rotating shaft mounting hole. 6 is a non-reflective material, 8 is a non-reflective part, 10 is a group of narrow strips, 11
12 is a coating, 12 is a reflective part, 14 is a metal disk, 16 is a coating, 20 is a rotating shaft

Claims (1)

[Claims] 1. A metal disc formed by a method such as photoelectroforming and having a rotating shaft mounting hole in the center, and a metal disc that extends radially along the inside of the outer periphery of the metal disc around the rotating shaft mounting hole. A non-reflective part in which a non-reflective material is spread or coated on the upper surface of the metal disk excluding the group of thin strip-shaped bodies arranged thereon, and a reflective layer formed with a film of a substance having high reflectivity on the upper surface of the group of narrow strip-shaped bodies. A rotating plate of a reflective rotary encoder with a 2. A disc made of highly reflective metal formed by a method such as photoelectroforming and having a rotating shaft mounting hole in the center, and radially arranged around the rotating shaft mounting hole along the inside outer circumference of the metal disc. Rotation of a reflective rotary encoder comprising a non-reflective part in which a non-reflective material is spread or coated on the metal disk excluding the group of narrow strips provided, and a reflective part formed by the radial strips. Board. 3. A metal disc formed by a method such as photoelectroforming, with a rotating shaft mounting hole in the center, and a highly reflective material coated or spread on the top surface, and a rotating shaft mounting hole along the inside of the outer periphery of the metal disc. A non-reflective part in which a non-reflective material is spread or coated on the metal disc except for a group of narrow strips arranged radially around the center, and a reflective part formed by the radial strips as they are. Rotating plate of reflective rotary encoder. 4. The metal disk is made of nickel, etc. Claim 1
The rotary plate of the reflective rotary encoder according to item 1 or 3. 5. A rotary plate for a reflective rotary encoder according to claim 1, item 2 or 3, which has a non-reflective portion on which a non-reflective material is spread or coated by electrodeposition. 6. The rotary plate of a reflective rotary encoder according to claim 3, which has a metal disk on which a highly reflective material is spread or coated by plating or the like. 7. The rotary plate of the reflective rotary encoder according to claim 1, which has a reflective portion formed by plating or the like using rhodium or the like as a material having high reflectivity. 8. The rotary plate of a reflective rotary encoder according to claim 2, wherein the highly reflective metal disk is made of rhodium or the like.