Electromechanical chopper for speed control of battery powered devices
US4132933A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1976 |
| Grant date | Jan 2, 1979 |
| Priority date | — |
| Expiry date | Dec 23, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/937
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A chopper for adjustably controlling the average value of the voltage supplied from a D.C. battery source to a motor load for adjustable speed control. The chopper comprises manually-operable spring-biasing means for applying force to close a contact to energize the motor and electromagnetic means simultaneously energized for re-opening the contact. This occurs at a high repetition rate so that the average value of the voltage across the motor determines the motor speed. This average value of voltage is proportional to the closed-to-open time ratio of the contact and is adjustable by manual control. Two versions are disclosed. In the first version, the spring-biasing force is applied to the contact by depressing a trigger. In the second version, the spring-biasing force is applied to the contact by rotation of a knob. Both versions may use either tension or compression spring force.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.