The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 21, 1977
Filed:
Feb. 11, 1976
Yoshio Adachi, Kodaira, JA;
Hitachi, Ltd., , JA;
Abstract
A system for driving a bipolar stepping motor by a pair of pulse driving currents wherein an output level of a control circuit is selected depending on one of the pulse drive currents applied just prior to the stoppage of the motor by a reset signal, switching of a set of signal transmitting paths for connecting between a reference signal generating circuit and a motor drive circuit is selected depending on an output level of the control circuit, that one of a pair of reference signals produced by the reference signal generating circuit during the operation of the motor which first appears after the release of the stop causes production of the other of the pulse drive currents by the selected path, and a predetermined time period after the release of the stop the pulse drive current of opposite polarity to that of the pulse drive current being applied to the motor which is just about to stop is applied to the motor to positively re-start the operation of the motor at a predetermined time.