Average power control apparatus and method
US4377739A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 1979 |
| Grant date | Mar 22, 1983 |
| Priority date | — |
| Expiry date | Jul 6, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/2003
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A power control method and apparatus maintains a constant average power at an electrical load, such as a fuser in an electrophotocopy machine. A power monitor measures the average power delivered to the load and compares the measured power to a predetermined power. A digital network receives an input signal from the power monitor and controls the coupling of power from an ac source to the load. When load power is less than a predetermined level, the digital network couples every half cycle of the ac power source to the load. When the load power is equal to or greater than the predetermined power, the digital network couples every third ac half cycle to the load. As a result, only half cycles of sequentially opposite polarity are coupled to the load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.