Title:
METHOD FOR DETECTING ABNORMALITY OF ENCODER
Document Type and Number:
Japanese Patent JPH05118871
Kind Code:
A
Abstract:
PURPOSE:To enable abnormality of an encoder to be detected easily by detecting whether an encoder output pulse between edge signals of at least one polarity position level signal matches a corresponding specified number or not. CONSTITUTION:A polarity position of a three-phase coil winding is detected by a polarity detector 2 of an AC servo motor 1, at least one out of them, for example leading and trailing edges of a V-phase signal are detected by an edge-detection circuit 7, and then a latch signal pulse is generated in synchronization with the edges. Then, a counter value latch circuit 5 counts and then stores a counter value of A-phase and B-phase pulse signals which are output from a 2-phase encoder 3 in synchronization with a pulse from the circuit 7. Then, a CPU 9 reads out a counter value which is stored in the circuit 5 in synchronization with a pulse from a synchronization interrupt clock 10, compares it with a specified numeric value which is stored previously, and then determines that the encoder is malfunctioning when they do not match.
Inventors:
MARUO SATOSHI
TATSUMI HIROYUKI
TATSUMI HIROYUKI
Application Number:
JP25306891A
Publication Date:
May 14, 1993
Filing Date:
September 03, 1991
Export Citation:
Assignee:
BROTHER IND LTD
International Classes:
G01D5/245; G01D5/244; (IPC1-7): G01D5/245
Attorney, Agent or Firm:
Takashi Tomizawa (2 outside)