Power tool trigger assembly
US6749028B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 2003 |
| Grant date | Jun 15, 2004 |
| Priority date | — |
| Expiry date | May 22, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H9/52
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.