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:
Aug. 24, 2004
Filed:
Nov. 06, 2002
Masaki Nakamichi, Tokyo, JP;
Kohji Hashimoto, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An abnormality detector for motor drive system easily detects, using a CPU, abnormality such as short circuit or disconnection in magnetic field coils of a motor, wiring, an open/close element, etc., which are controlled by a microprocessor (CPU). The open/close elements conducting an open/close operation sequentially in response to pulse outputs P , P generated by the CPU, drive the magnetic field coils. Surge voltages generated upon interrupting the mentioned open/close elements are OR connected through a diode, and input to a temporary storage circuit. Then the CPU reads out, stores and resets the surge voltages using pulse edges of the pulse output P or P . When any generation of the surge voltage is not stored in the temporary storage circuit, the CPU operates an abnormality alarm display.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile