JP3238686B2 - Encoder signal processing method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an encoder signal processing method and apparatus, and more particularly to averaging a digital encoder signal after A / D conversion in a predetermined time unit and converting the averaged digital encoder signal into an absolute signal. Accordingly, the present invention relates to a novel improvement for averaging a noise component on an encoder signal and reducing the influence (error due to noise) on an absolute signal.

[0002]

2. Description of the Related Art As a conventional encoder signal processing method of this type, a method shown in FIG. 4 has been generally employed. That is, what is denoted by reference numeral 1 in FIG. 4 is an analog two-phase encoder signal obtained from a detection unit (not shown) of the encoder, and this encoder signal 1 is input to the A / D conversion unit 2 and I have. The digital encoder signal 1a that has been A / D converted by the A / D converter 2 is converted into an absolute signal by a well-known absolute signal generator 3, and an absolute signal 4 is generated.

[0003]

Since the conventional encoder signal processing method is configured as described above, there are the following problems. That is, since the encoder signal is an analog signal, for example, when an external noise 1b rides on the two-phase analog signal as shown in FIG. 2A, the noise 1b is different from the absolute signal. (A) as shown in FIG.
The noise 1b is generated at the timing corresponding to the noise 1b, and a serious erroneous process is performed in an absolute signal processing unit for processing the absolute signal. Was caused.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and in particular, averages a digital encoder signal after A / D conversion in a predetermined time unit and absolutely converts the averaged digital encoder signal. An object of the present invention is to provide an encoder signal processing method and apparatus in which a noise component on an encoder signal is averaged by signalization, and an influence on an absolute signal (error due to noise) is reduced.

[0005]

SUMMARY OF THE INVENTION An encoder signal processing method and apparatus according to the present invention is an encoder which generates a digital encoder signal obtained by A / D conversion of an encoder signal into an absolute signal via an absolute signal generator. In the signal processing method, the digital encoder signal is averaged in a predetermined time unit, and the absolute signal is obtained based on the averaged digital encoder signal obtained after averaging, and the encoder signal is A / D converted. In the encoder signal processing method in which the obtained digital encoder signal is generated as an absolute signal through an absolute signal generation unit, the digital encoder signal is averaged in a predetermined time unit, and the averaged digital signal obtained after averaging is obtained. Transmit the encoder signal to the absolute A structure having a time average circuit for applying to preparative signal generator.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an encoder signal processing method and apparatus according to the present invention will be described below with reference to the drawings. The same or equivalent parts as those in the conventional example will be described using the same reference numerals. In FIG. 1, what is indicated by reference numeral 1 is a two-phase encoder signal of an analog signal obtained from a detector (not shown) of the encoder, and the encoder signal 1 is input to the A / D converter 2. .

The digital encoder signal 1a that has been A / D converted by the A / D conversion section 2 is output to a time averaging circuit section 10
Has been entered. Since the level of the digital encoder signal 1a input to the time averaging circuit unit 10 is averaged in a predetermined time unit, the noise 1b is added to the encoder signal 1 shown in FIG. When the averaged digital encoder signal 1A averaged by the time averaging circuit unit 10 is converted into an absolute signal by the well-known absolute signal generation unit 3 and the absolute signal 4 is generated, (C), the level of the noise 1b is greatly reduced as compared with the related art, and the accuracy of the absolute signal 4 is greatly improved. As an example, the time averaging circuit unit 10 uses a four-stage register 100 that is clock-controlled as shown in FIG. 3 and adds the averaged digital encoder signal 1A after adding by the adder 101. It is a configuration to output.

[0008]

Since the encoder signal processing method and apparatus according to the present invention are configured as described above, the following effects can be obtained. That is, since the digital encoder signal is averaged in a predetermined time unit by the time averaging circuit unit, the noise itself is also averaged, the level is reduced, and the level of the noise on the absolute signal is close to a negligible state, and the It is possible to prevent a malfunction or the like from occurring.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an encoder signal processing method and apparatus according to the present invention.

FIG. 2 is a waveform diagram of an encoder signal and an absolute signal according to the present invention and the related art.

FIG. 3 is a specific block diagram of a main part of FIG. 1;

FIG. 4 is a block diagram of a conventional method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Encoder signal 1a Digital encoder signal 1A Digital encoder signal after averaging 3 Absolute signal generation part 4 Absolute signal 10 Time averaging circuit part

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) G01D 5/00-5/64 G01B 11/00-11/30 G01B 7/00-7/34 G01P 1 / 00-3/80 H03M 1/00-1/88

Claims (2)

(57) [Claims] An encoder signal processing method for generating a digital encoder signal (1a) obtained by A / D conversion of an encoder signal (1) into an absolute signal (4) via an absolute signal generator (3). Wherein the digital encoder signal (1a) is averaged for a predetermined time unit, and the absolute signal (4) is obtained based on the averaged digital encoder signal (1A) obtained after the averaging. Processing method. 2. An encoder signal processing method for generating a digital encoder signal (1a) obtained by A / D conversion of an encoder signal (1) into an absolute signal (4) via an absolute signal generator (3). A time averaging circuit for averaging the digital encoder signal (1a) in a predetermined time unit and applying the averaged digital encoder signal (1A) obtained after the averaging to the absolute signal generation unit (3). An encoder signal processing device having (10).