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, 2004
Filed:
May. 22, 2003
Kai Chi Chan, Chaiwan, HK;
Man Ting Ho, Chaiwan, HK;
Defond Components Limited, Chaiwan, HK;
Abstract
A trigger assembly for controlling an electric power tool including a motor comprises a base for fixing within the power tool and a trigger supported by the base for inward and outward movement, the trigger being resiliently biassed outwards. The base has a housing including an opening open to the interior of the power tool. A switch provided in the housing is operable in response to the movement of the trigger to switch on and off the motor. An electronic operating circuitry provided in the housing includes a solid-state device for switching at a frequency having a variable duty cycle to control the operation of the motor when the switch is closed. Also included is a flywheel diode for the motor, which is operable when the solid-state device is non-conducting while switching. The diode is supported at or adjacent the housing opening to facilitate heat dissipation.