JPH04281382A - Control method for position of motor using serial 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]

0001

[Industrial Application Field] The present invention relates to a method for controlling the position of a motor using a serial absolute encoder, and in particular, by controlling a motor driver using both incremental signals and absolute signals, high precision and high reliability can be achieved. This invention relates to a novel improvement for obtaining a motor rotation of .

0002

2. Description of the Related Art Conventionally, a motor position control method using this type of encoder is generally known, for example, in the case of a motor with an encoder disclosed in Japanese Unexamined Patent Publication No. 1-55041, as shown in FIG. The control method shown in was adopted.

That is, what is indicated by the reference numeral 1 in FIG. 2 is a motor with an encoder that integrally has an encoder 2 and a motor 3. An absolute signal 4 or an incremental signal 5 obtained from the encoder 2 is transmitted to a motor driver 6. The signal is input to the control device 7 via the control device 7.

In this control device 7, a control signal 8 is output based on the absolute signal 4 or the incremental signal 5, and this control signal 8 is input to a motor driver 6 to control the rotation and position of the motor 3. There is.

[0005]

[Problems to be Solved by the Invention] Since the conventional motor position control method was constructed as described above, the following problems existed. In other words, since the motor driver has been controlled using only either the absolute signal or the incremental signal obtained from the encoder, it is impossible to control the absolute position using only the incremental signal. It was difficult to distinguish errors due to noise, and it was impossible to prevent a decrease in reliability. In addition, if only absolute signals are used, the number of signal lines increases and reliability decreases.
As with the case of only incremental signals, it was difficult to distinguish errors due to noise. Furthermore, since only one of the signals is used, it is difficult to detect a wire breakage, and when a wire breakage occurs, motor control becomes impossible, making it extremely difficult to improve reliability.

The present invention has been made to solve the above-mentioned problems, and in particular, to obtain highly reliable motor rotation by controlling a motor driver using both incremental signals and absolute signals. The present invention aims to provide a method for controlling the position of a motor using a serial absolute encoder.

[0007]

[Means for Solving the Problems] A motor position control method using a serial absolute encoder according to the present invention is a motor position control method in which a rotation detection signal from an encoder is used as a control signal to control a motor driver to rotate the motor. In the position control method, the encoder is a serial absolute encoder, and the absolute signal and the incremental signal are converted into parallel signals as rotation detection signals, and then input to the control device.

[0008]

[Operation] In the motor position control method using a serial absolute encoder according to the present invention, the motor position data is detected by the serial absolute encoder, and the absolute signal and incremental signal obtained from the serial absolute encoder are used to control the motor driver. At the same time, it is converted into parallel by a serial/parallel converter.

The absolute signal and incremental signal after the parallel conversion are input to a control device, and the control device applies a control signal to the motor driver based on these signals to control the motor position.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a motor position control method using a serial absolute encoder according to the present invention will be described in detail below with reference to the drawings. Note that the same or equivalent parts as in the conventional example will be described using the same reference numerals. Figure 1
FIG. 1 is a block diagram showing a motor position control method using a serial absolute encoder according to the present invention.

The reference numeral 1 in the figure is a motor with an encoder that integrally includes a serial absolute encoder 2 and a motor 3, and an absolute signal 4 and an incremental signal 5, which are rotation detection signals obtained from the serial absolute encoder 2. is the serial/parallel converter 1 in the serial state via the motor driver 6.
It is entered as 0. The above-mentioned serial absolute encoder 2 is an encoder that serially outputs the incremental signal 5 and the absolute signal 4.

The signals 4 and 5 inputted to the serial/parallel converter 10 are converted into parallel signals and then inputted to the control device 7 as an absolute signal 4 and an incremental signal 5 in a parallel state.

In this control device 7, these two types of signals 4
, 5 to the motor driver 6 based on the control signal 8.
Enter. This motor driver 6 can control the position of the motor 3 using this control signal 8.

Therefore, since the control signal 8 is obtained based on the above-mentioned incremental signal 5 and absolute signal 4, if either signal 4 or 5 is abnormal, it can be determined by comparing both signals 4 and 5. The control signal 8 can be output based on only one of the signals 4 and 5.

In addition, in the above-mentioned serial absolute encoder, the code pattern of the rotating disk is, as is well known,
An optical encoder is used in which a pattern for generating an incremental signal 5 and a pattern for generating an absolute signal 4 are formed.

[0016]

Effects of the Invention Since the motor position control method using a serial absolute encoder according to the present invention is configured as described above, the following effects can be obtained. (1). Since both incremental and absolute signals are used simultaneously, absolute position control is possible. (2). If only incremental signals are used, there will be errors due to noise, but since two signals are used,
Noise errors can be determined using the absolute signal. (3). Since two signals are used, if there is a problem such as wire breakage in either one, it can be reliably detected by comparing both signals, and malfunction of the motor can be prevented. (4). Since two signals are used, even if one signal becomes abnormal, the motor can be controlled by using the other signal, and the redundancy (reliability) of the motor can be improved. (5). Since a serial absolute encoder is used as the encoder, the number of lead wires for outputting output signals is small, and both incremental signals and absolute signals can be obtained with one encoder.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a motor position control method using a serial absolute encoder according to the present invention.

FIG. 2 is a block diagram showing a conventional motor position control method using an encoder.

[Explanation of symbols]

2 Encoder (serial absolute encoder) 3
Motor 4 Absolute signal (rotation detection signal) 5
Incremental signal (rotation detection signal) 7
Control device 8 control signal

Claims (1)

[Claims] Claim 1: A rotation detection signal (4, 5) from an encoder (2) is input to a control device (7), and this control device (
The motor driver (6) is controlled by the control signal (8) from the
In the motor position control method, the encoder (2) is a serial absolute encoder, and the absolute signal (4) and the incremental signal (5) are used as the rotation detection signals in parallel. A method for controlling the position of a motor using a serial absolute encoder, characterized in that the converted data is input to the control device (7).