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. 15, 1993
Filed:
Jan. 16, 1992
Osamu Yaguchi, Kashiwazaki, JP;
Mitsunori Arakawa, Kashiwazaki, JP;
Kabushiki Kaisha Riken, Tokyo, JP;
Abstract
A DC power supply for a DC motor is controlled by a drive transistor. An 'ON' state of the drive transistor is maintained by a comparator which compares a terminal voltage at a point between the DC motor and the drive transistor with a reference voltage supplied from the power supply. A clock pulse is applied to the drive transistor to make it periodically turn off in order to detect an induced voltage depending upon the rotation rate of the DC motor. The drive transistor returns to turn off upon stopping the rotating DC motor by force. A regulator is provided between the power supply and the reference voltage. A restraint torque and a rotation rate control means are also provided. Alternatively, a pulsating power supply is provided instead of the DC power supply and the clock.