JPH0449540Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a rotary encoder, particularly to the configuration of a fixed slit plate and a rotating slit disk of an optical rotary encoder.

(Prior Art) Conventionally, this type of rotary encoder has a fixed slit plate configured as shown in Figs. 4 and 5 in order to be able to handle both high pulses and low pulses. be. In these figures, 41 is a fixed slit plate, 42 to 44 are slits, and 45 to 47 are light emitting elements or light receiving elements located at corresponding positions in the axial direction.

Fig. 4 is applied to high-pulse applications, in which light from the same slit of a rotating slit disk (see reference numeral 14 in Fig. 1) is transmitted to light-receiving elements 4 with different phases.
5 and 47 respectively receive position signal pulses with a 90° phase difference. However, in the case of low pulses, since the relative positions of the light receiving elements 45 and 47 are fixed, a pulse signal with a phase difference of 90° may not be obtained. For this reason, as shown in FIG. 5, light receiving elements 45 and 47 are provided on different diameters, and slits are provided in the rotating slit disk at positions corresponding to the light receiving elements, and light is received from the slits. As a result, position signal pulses with a 90° phase difference similar to the above are obtained.

(Problems to be solved by the invention) In the conventional rotary encoder as described above, three pairs of light emitting elements and light receiving elements can be attached, so that it can handle both high pulses and low pulses. It is configured.

However, when applying to low pulses and trying to detect the origin position further, the configuration shown in Fig. 5 cannot be used, and a configuration for attaching a light emitting element (or light receiving element) for origin detection is required. However, there was a problem in that the supporting part to which the light emitting element (or light receiving element) is attached had to be newly made.

This invention was made in order to solve this problem, and it can be used at low pulses without changing the structure of the support part of the conventional light emitting element and light receiving element.
The purpose of the present invention is to obtain a rotary encoder that can detect a 90° phase difference and an origin position.

(Means for Solving the Problems) The rotary encoder according to this invention has two pairs of support parts for a light emitting element and a light receiving element provided at a predetermined interval on the same diameter, and a support part for two pairs of light emitting elements and light receiving elements provided at a predetermined interval on the same diameter, In a rotary encoder having a pair of light emitting elements and a supporting part for a light receiving element provided on the rotary encoder,
A light emitting element and a light receiving element are respectively attached to the support parts for the two pairs of light emitting elements and light receiving elements and the supporting parts for the one pair of light emitting elements and light receiving elements.

A first slit corresponding to the outer peripheral half of one of the two pairs of light emitting elements and light receiving elements, a second slit corresponding to the center half of the other light emitting element, and a second slit corresponding to the center half of the other light emitting element; A fixed slit plate provided with a third slit corresponding to the element, and two rows of slits provided on a diameter corresponding to the first slit and the second slit with a predetermined phase difference from each other. , and a rotating slit disk provided with a slit for detecting the origin provided on a diameter corresponding to the third slit.

(Function) In this device, the two pairs of light emitting elements and light receiving elements transmit and receive position signal pulses with a 90° phase difference through the first slit and second slit of the rotating slit disk, respectively. At the same time, the pair of light emitting element and light receiving element transmit and receive through the third slit of the rotating slit disk to obtain an origin position signal pulse.

(Example) FIG. 1 is a diagram showing an example of this invention.
In the figure, 1 is the rotating shaft to be detected;
2, 3, 4 (3 refer to Figure 2) are light emitting elements; 5,
6 and 7 (6 is shown in FIG. 2) are light receiving elements. 8
1 is a support member for the light emitting elements, and holes for attaching the light emitting elements 2, 3, and 4 are provided. 9 is a support member for the light receiving elements 5, 6, and 7. 1 to 9 of the above
Each component is basically the same as the conventional one.

A fixed slit plate 10 is provided with slits 11, 12, and 13 as shown in FIG. The slit 11 is connected to the light emitting element 2 and the light receiving element 5.
It is provided at a position in the axial direction corresponding to the outer peripheral half of the fixed slit. The slit 12 is provided at a position in the axial direction corresponding to the central half of the fixed slit of the light emitting element 3 and the light receiving element 6. The slit 13 is provided at a position in the axial direction corresponding to the center of the light emitting element 4 and the light receiving element 7.

14 is a rotating slit disk, and as shown in FIG. 3, three rows of slits 15, 1 are arranged on different diameters.
6 and 17 are provided. The slit 15 is connected to the slit 11 of the fixed slit plate 10, and the slit 16
corresponds to slit 12, and slit 17
is provided at a position on the diameter corresponding to the slit 13.

The above configurations can be divided into the following three groups based on the light path from light emission to light reception. That is, the light emitting element 2, the slit 11 of the fixed slit plate 10,
A first group consisting of the slit 15 of the rotating slit disk 14 and the light receiving element 5, and a second group consisting of the light emitting element 3, the slit 12 of the fixed slit plate 10, the slit 16 of the rotating slit disk 14, and the light receiving element 6. and a third group consisting of the light emitting element 4, the slit 13 of the fixed slit plate 10, the slit 17 of the rotating slit disk 14, and the light receiving element 7.

The output of the first group of light receiving elements 5 and the output of the second group of light receiving elements 6 are 90° due to the phase difference between the mounting positions of these elements and the phase difference between the slits 15 and 16 of the rotating slit disk 14. Send position signal pulses with different phases. Also, the third
The output of the light receiving element 7 of the group sends out an origin signal pulse indicating the absolute position to the first group and the second group.

In the rotary encoder configured as described above, the rotary slit disk 14 rotates as the shaft 1 rotates. At this time, the light from each light emitting element 2, 3, 4 passes through each slit of the fixed slit plate 10 and the rotating slit disk 14,
It reaches each light receiving element 5, 6, and 7. Each light receiving element 5,
The timing of light reception of 6 and 7 differs according to the above groups. For this reason, the light receiving element 5
and 6 send out position pulse signals that are different from each other by 90 degrees, and the light receiving element 7 sends out an origin position signal pulse.

(Effects of the invention) As described above, according to this invention, the slits of the fixed slit plate can be made to correspond to the three rows of slits of the rotating slit disk, while maintaining the conventional positions of the light emitting element and the light receiving element. , two position signal pulses and an origin position signal pulse can be obtained without changing the supporting parts of the conventional light emitting element and light receiving element.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a rotary encoder showing an embodiment of this invention, Fig. 2 is an explanatory diagram showing the correspondence between the fixed slit plate slit in Fig. 1 and the light emitting element (light receiving element), Fig. 3 1 is an explanatory diagram of the rotating slit disc shown in FIG. 1, and FIGS. 4 and 5 are explanatory diagrams of the conventional fixed slit disc, respectively. In the figure, 2, 3, 4 are light emitting elements, 5, 6,
7 is a light receiving element, 10 is a fixed slit plate, 11, 1
2 and 13 are slits, 14 is a rotating slit disk,
15, 16, and 17 are slits. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims for Utility Model Registration] Support parts for two pairs of light emitting elements and light receiving elements provided on the same diameter at a predetermined interval, and a pair of light emitting elements provided on a different diameter from the above. and a light-receiving element support part, respectively, wherein the light-emitting element and the light-receiving element are attached to the two pairs of light-emitting element and light-receiving element support parts and the one pair of light-emitting element and light-receiving element support parts; A first slit corresponding to the outer peripheral half of one of the two light emitting elements and a light receiving element, a second slit corresponding to the center half of the other light emitting element, and a second slit corresponding to the pair of light emitting elements. a fixed slit plate provided with a third slit; two rows of slits provided with a predetermined phase difference between them on diameters corresponding to the first slit and the second slit, respectively; A rotary encoder comprising: a rotating slit disk having a slit for detecting the origin provided on a diameter corresponding to the third slit;