EP 0250862 B1 19891129 - METHOD AND DEVICE FOR CONTROLLING A STEPPER MOTOR
Title (en)
METHOD AND DEVICE FOR CONTROLLING A STEPPER MOTOR
Publication
Application
Priority
CH 258586 A 19860626
Abstract (en)
[origin: US4754210A] The method and the device described are intended to avoid the dissipation of electrical energy that occurs in the coil of a stepping motor when the coil is short-circuited permanently between two drive pulses. The method comprises short-circuiting the coil at the end (t1) of the drive pulse, then putting it on open circuit at the instant (t2) when the current (Ic) flowing through it during the short-circuit becomes zero, and short-circuiting the coil again at the instant (t3) when the voltage induced in it by the rotation of the rotor while the coil is on open circuit becomes zero or reaches a predetermined value (Ud). The device is designed to carry out the method. The invention is applicable to the control of stepping motors of the type for instance that are fitted in electronic timepieces having a hand display.
IPC 1-7
IPC 8 full level
CPC (source: EP US)
G04C 3/14 (2013.01 - EP US)
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
EP 0250862 A1 19880107; EP 0250862 B1 19891129; CH 665084G A3 19880429; DE 3761064 D1 19900104; JP 2655645 B2 19970924; JP S637199 A 19880113; US 4754210 A 19880628
DOCDB simple family (application)
EP 87107571 A 19870525; CH 258586 A 19860626; DE 3761064 T 19870525; JP 15670087 A 19870625; US 5320187 A 19870522