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:
Jul. 20, 2004
Filed:
Apr. 02, 2002
Raymond Wai Hang Chu, Chai Wan, HK;
Defond Manufacturing Limited, Chai Wan, HK;
Abstract
A power supply module for use between an AC/DC power supply unit and an electrical power tool driven by an electric motor and powered by a rechargeable battery pack which has a normal operating voltage and a higher fully-charged terminal voltage. The module includes an input connectable to the supply unit and an output connectable in parallel to the battery pack, and an operating circuit for delivering DC power from the supply unit to the tool in parallel with the battery pack. The operating circuit provides a DC operating voltage at the output of a value between the normal operating voltage and the fully-charged terminal voltage of the battery pack, and provides an output current limited to a predetermined value. The circuit has a comparator for determining whether the output current is less than or is increasing toward exceeding the predetermined value provides a corresponding control signal. The circuit includes a switching device for controlling, in response to the control signal, the power delivered to the tool as a direct DC current when the output current is below the predetermined value or as a pulsating DC current when the output current is increasing toward exceeding the predetermined value.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile