Power relay switching control device for microwave oven
US4833284A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1987 |
| Grant date | May 23, 1989 |
| Priority date | — |
| Expiry date | May 29, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S323/908
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A power relay for a switching control device of a microwave oven, designed to prolong the life of the power relay by alternately carrying out the drive of the power relay used for controlling the power in a microwave oven at the positive (+) cycle and the negative (-) cycle of the alternating current input voltage, respectively. The output signal of the 50 Hz/60 Hz clock generator for generating the clock signal corresponds to the frequency of the alternating current input voltage and is combined with the output signal of the power relay ON/OFF generator. The power relay ON/OFF control part is composed so as to alternately realize the ON-point and the OFF-point of power relay at the positive cycle and the negative cycle of the alternating current input voltage, respectively, so that no potential difference takespace in one direction between contact of the power relay, and the life is thereby prolonged.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.