JPH01303097A - Origin detection device - 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 Field of Industrial Application This invention relates to an origin detection device using a pulse motor for use in industrial robots, transfer device 2 positioning devices, and the like.

BACKGROUND ART FIG. 5 is a block diagram showing a conventional origin detection device. When a pulse motor 2 mounted on a support 1 rotates,
Sufu IJ connected to one end of the rotating shaft of the pulse motor 2
Since the j-u axis (a shaft with a spiral groove formed on the outer periphery) 3 also rotates, the slider 4 moves in the direction of arrow a, and the rotary shaft connected to the other end of the rotating shaft of the pulse smoke 2 rotates. The plate 6 also rotates in the direction of one arrow.

Therefore, when detecting the origin, the moving axis origin signal S1 shown in FIG. When a rotational origin signal S2 shown in FIG. 6(2) from the rotational axis origin detector 7 which detects a magnet in a predetermined section provided on the outer circumference of the rotary plate 6 is supplied to the ant circuit 8. An origin signal S3 is obtained as shown in FIG. 6(3).

However, in the conventional origin detector device described above, the detection range of the rotary axis origin detector 7 has a wide range, and the origin detection width is more sensitive than the resolution of the pulse smoke 23. -/ There was a problem that accurate origin detection and repeatable positioning accuracy could not be expected.

In some cases, an optical encoder is used as the rotational axis origin detector 7, but there is a problem in that it is very expensive compared to the detection accuracy that can be obtained.

The present invention solves these conventional problems, and aims to provide an origin detection device that can detect the origin position with high precision and can be manufactured at low cost.

Means for Solving the Problems In order to achieve the above object, the present invention has a configuration in which the phase origin signal of the phase origin detection means that encodes the excitation voltage of each phase of the pulse motor as a phase signal is also used to detect the origin. It is something.

Therefore, according to the present invention, the origin can be detected using a phase origin signal that has the same resolution as the pulse motor, which is obtained by encoding the excitation voltage of each phase of the pulse motor.

Embodiment FIG. 1 is a configuration diagram showing an origin detector according to an embodiment of the present invention.

In Fig. 1, 1 is a support (frame), 2 is a pulse motor attached to the support 1, and 3 is a spriller shaft connected to one end of the pulse smoke 2 and having a spiral groove formed on its outer periphery. and is rotatably supported by a support 1.

Reference numeral 4 indicates a movable element engaged with the screw shaft 3, which moves in the direction of arrow a as the screw shaft 30 rotates.

5 indicates a moving axis origin detector, and when the moving element 4 is detected,
It outputs a moving axis origin signal S1.

Reference numeral 6 denotes a rotating plate connected to the other end of the rotating shaft of the pulse motor 2, and a magnet, for example, is attached to a predetermined range of the outer circumferential portion corresponding to one revolution of the rotating shaft of the pulse motor 2.

7 is a rotary axis origin detector (Hall element) that detects the magnet attached to the rotary plate 6, and 9 is an encoder, which encodes the excitation voltage of each phase of the pulse motor 2 as a phase signal to generate a phase origin signal. 5 b/ No. S4 is obtained.

10 is a moving axis origin detector 55, a rotation axis origin detector 7, and an encoder 9 output signals S., S2. An AND circuit with S4 as an input is shown.

Next, the operation of the above embodiment will be explained using an example in which a two-phase pulse motor is used as the pulse motor.

In the above embodiment, the excitation sequence when driving the pulse motor 2 consists of 8 steps (
It is repeated at a cycle of 7.2 degrees - 〇9 degrees x 8), so the third
As an example of the configuration is shown in the figure, impark circuits 9L, 9
A of encoder 9 composed of I2 and AND circuit 9A
When the excitation voltages of the two-phase, B-phase, and government phase are encoded as phase signals, the phase origin signal S4 is generated once every 8 steps.
can be obtained from the encoder 9.

Note that the phase origin signal S4 obtained by the encoder 9 corresponds to one step of the pulse motor 2, that is, the minimum unit of resolution.

When the pulse motor 2 attached to the support 1 rotates, the scree shaft 3 connected to the -68-7 end of the rotation shaft of the pulse motor 2 also rotates, so that the slider 4 moves in the direction of arrow a. At the same time, the pulse motor 2
The rotating plate 6 connected to the other end of the rotating shaft also rotates in the direction of arrow 1].

Therefore, when detecting the origin, the moving axis origin signal S1 shown in FIG. The encoder 9 encodes the rotary shaft origin signal S2 shown in FIG.
The phase origin signal S4 shown in FIG. 4 (3) and the AND circuit 1
0, the origin signal S5 is obtained as shown in FIG. 4 (4).

In the above embodiment, the inverter circuit 9■1゜9I2
Although the example has been described using the AND circuit 9A, other circuit configurations that operate in the same manner may be used.

Effects of the Invention As is clear from the above embodiments, the present invention has the following advantages:
-7 Since the configuration is such that the phase origin signal of the phase origin detection means, which encodes the excitation voltage of each phase of the pulse motor as a phase signal, is also used to detect the origin, the origin can be detected using the phase origin signal of the resolution of the pulse motor itself. This has the effect of being able to detect the origin position with high accuracy.

Furthermore, since the origin position can be detected with high precision without using an optical encoder, there is an advantage that the device can be manufactured at low cost.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing an origin detection device according to an embodiment of the present invention, Fig. 2 (1) to (4) are timing charts showing excitation signals of two-phase pulse smoke, and Fig. 3 encodes phase signals. A circuit diagram showing an encoder, Fig. 4 (1) ~
(4) is a timing chart showing each signal of an embodiment of the present invention, FIG. 5 is a configuration diagram showing a conventional origin detection device, and FIGS. 6 (1) to (1) show each signal of the conventional example. FIG. 2 Pulse motor, 3 Sfreera shaft, 4/Scillator, 5
Moving origin detector, 6 Rotating plate, 7 Rotating axis origin detector, 9 Encoder, 10 Name of AND circuit agent Patent attorney Satoshi Nakao and 1 other person Procedural amendment (method)

Claims (1)

[Claims] a pulse motor, a movement origin detection means for detecting a movement origin of a moving part driven by the pulse motor, a rotation axis origin detection means for detecting a rotation axis origin of a rotation axis of the pulse motor, and each of the pulse motors. a phase origin detection means that detects a phase origin by encoding a phase excitation voltage as a phase signal, and when the moving origin detection means, the rotation axis origin detection means, and the phase origin detection means detect their respective origins; An origin detection device comprising an origin detection means for outputting an origin signal.