JPH011912A - absolute encoder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention a. Field of Industrial Application The present invention relates to an absolute encoder, and in particular, by arranging a plurality of fixed slit portions each having a different number of fixed slits at the same circumferential position, small diameter Concerning a novel improvement to be able to obtain absolute values in the configuration.

b. Conventional technology Various configurations have been proposed for this type of absolute encoder that has been used in the past, but here we will discuss the most typical configurations. Although the figures are not disclosed, the rotating swan provided on the rotating disk is formed on the circumference, and forms a disk track corresponding to the number of bits of the output signal. In the radial direction where the disk tracks of the rotating slit correspond one-to-one, disk tracks corresponding to the number of output signal bits are parallel to each other?
It was formed with a diameter of Otsu.

Problems to be Solved by Invention C (Since the R-end absolute encoder was configured as described above, it had the following problems.

Unless the number of disk tracks corresponding to the number of output signal bits is formed, it is not possible to obtain the output signal for obtaining the absolute value, so multiple disk tracks with different diameters are formed on the rotating disk. For example, in a high precision high pitch encoder, the diameter of the rotating disk must be increased, and the outer shape of the encoder itself must also be increased.

In addition, it is extremely difficult to form multiple disk tracks on a compact rotating disk in response to the need for miniaturization with a configuration that can output absolute value signals. It is extremely difficult to arrange the fixed slit plate and the light receiving section corresponding to the disk track in the radial direction thereof, and it is extremely difficult to obtain a miniaturized absolute encoder.

The present invention has been made to solve the above-mentioned problems, and in particular, by arranging a plurality of fixed slit sections each containing a different number of fixed slits at the same circumferential position, small diameter An object of the present invention is to provide an absolute encoder that can obtain an absolute value with a configuration.

d1 Means for Solving Problems The absolute encoder according to the present invention includes a rotating disk having at least one disk track formed of a plurality of rotating slits, which is attached to a rotating shaft rotatably provided on a base; a plurality of light emitting parts facing each other on one side of the rotating disk and disposed at mutually different angular positions; a fixed slit plate fixedly installed on the other side of the rotating disk facing the same; a plurality of fixed slit parts having different numbers of fixed slits on the same circumferential position of the fixed slit plate and arranged at different angular positions;
It has a configuration in which a plurality of light receiving parts are arranged facing each light emitting part at an outer position of the fixed slit plate.

C9 action In the absolute encoder according to the present invention, the output signals 3 of different frequencies are brought into parallel state through each fixed slit part of the fixed slit plate formed corresponding to one disk track of the rotating disk. For example, in the case of a configuration with four fixed slits, it is possible to obtain the same number of output signal bits with the number of disk tracks using conventional rotating slits, and the outer size of the rotating disk can be increased. 111, and a smaller absolute encoder can be obtained.

[Embodiments] Hereinafter, preferred embodiments of the absolute encoder according to the present invention will be described in detail with reference to the drawings.

1 to 41 are for showing the configuration of the absolute encoder according to the present invention. First, the encoder indicated by the reference numeral 1 in FIG. 4 is rotatably mounted on the bearing 3 of the base 2. A plurality of rotating slits 1a are formed at an angular interval of 45 degrees from each other on the same circumferential position of the rotating disk 1. 1a forms one disk track.

On one side (upper side) of the rotating disk 1, there is a handle (not shown).
- A circuit board 6 having a processing circuit section 5 made of an IC is fixed by a means, and on the lower surface of this circuit board 6,
A plurality of light emitting units 7 are provided at 4g intervals at 90 degrees.
(Only two are shown in the drawing).

On the other side (lower side) of the rotating disk 1, there is a fixed slit plate having a plurality of fixed slit parts 01 to G4 formed at the same circumferential position and at 90 degree intervals as shown in FIG. 8 is fixedly provided via a mounting means (not shown).

Each of the fixed slit parts 1 to G1 to G4 has a different number of fixed slits 8a, as shown in FIG. , are arranged corresponding to each of the light emitting sections 7.

Four light-receiving sections 9 fixed by mounting means (not shown) are disposed at an outer position (below) of the fixed slit plate 8, and each of these light-receiving sections 9 connects to each of the fixed slit sections 61 to G.
4, respectively.

Further, a casing 10 is provided on the base 1, and an input/output line 11 connected to the processing circuit section 5 is configured as described above with a bush 12 provided on the casing 10. The operation will be explained.

First, by rotating the rotary disk 8, the output signal waveforms obtained in parallel from each light receiving section 9 via each fixed slit section 01 to G4 are as shown in FIG. is obtained by the fixed slit section G1, the output signal 2 is obtained by the fixed slit section G2, the output signal 3 is obtained by the fixed slit section G3, and the output signal 4 is obtained by the fixed slit section G4.

Therefore, the slit pattern of each fixed slit section 61 to G4 shown in FIG. 2 is a pattern for extracting a general alternating BCD signal. By arranging them at positions shifted by an integer multiple of the pitch of 8a, it is possible to extract an alternating #BCD signal having four signals.

In this embodiment, only the case where a plurality of fixed slit portions are provided at one and the same circumferential position has been described, but for example, when a plurality of disk tracks and fixed slit tracks are provided ( Similar effects can be obtained not with a large number of tracks as in the conventional case, but within the designable range allowed by the size of the diameter.

g0 Effects of the Invention Since the absolute encoder according to the invention is configured as described above, it is possible to obtain the following effects.

Rotating slit for multiple tracks (4 tracks in the example) by one track (disk track)
Therefore, the diameter can be made much smaller than the conventional configuration, and an ultra-compact absolute encoder can be obtained.

Further, the rotary slit does not have to form a special pattern unlike the conventional configuration, and a general incremental type slit pattern can be used, and the slit processing is extremely easy. Furthermore, the machining error can be reduced, the accuracy error of the encoder can also be reduced, and a highly accurate absolute encoder can be obtained.

[Brief explanation of the drawing]

The drawings are for showing an absolute encoder according to the present invention, and FIG. 1 is an enlarged plan view showing a rotating disk, and FIG. 2 is an enlarged plan view showing a rotating disk.
The figure is an enlarged shell IA showing the fixed slit plate, Fig. 3 is an enlarged side view of the main parts, Fig. 4 is a sectional view showing the overall configuration, and Fig. 5 is a configuration diagram showing the relationship between the output signal and each fixed slit. It is. 1 is a rotating disk, 1a is a rotating slit, 2 is a base, 4 is a rotating shaft, 7 is a light emitting part, 8 is a fixed slit plate, 8a is a fixed slit, 61 to G4 are fixed slit parts, 9 is a light receiving part be. Figure 1 Figure 3 Figure 4

Claims (3)

[Claims] (1) Rotating shaft (4) rotatably provided on the base (2)
a rotating disk having at least one disk track consisting of a plurality of rotating slits (1a); A plurality of light emitting parts (7), a fixed slit plate (8) fixedly installed on the other side of the rotating disk (1) opposite to this, and the same circumferential position of the fixed slit plate (8). Different numbers of fixed slits (8
a) and a plurality of fixed slit parts (G1 to G4) arranged at mutually different angular positions, and arranged opposite to each of the light emitting parts (7) at an outer position of the fixed slit plate (8). and a plurality of light receiving sections (9), and each of the fixed slit sections (G1) is arranged in parallel from each of the light receiving sections (9).
- G4) An absolute encoder characterized in that it outputs a signal corresponding to G4). (2) The absolute encoder according to claim 1, wherein each of the fixed slit portions (G1 to G4) consists of four pieces. (3) Each rotating slit (1a), each fixed slit section (G1 to G4), each light emitting section (7), and each light receiving section (9) are arranged at a plurality of the same circumferential positions. An absolute encoder according to claim 1 or 2, characterized in that: