Patent · US Expired

Programmable wall switch for controlling lighting times and loads

US4521843A · kind A · utility

58Cited by
16References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 16, 1982
Grant dateJun 4, 1985
Priority date
Expiry dateAug 16, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/40
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A programmable wall switch for controlling the time for turning on and for turning off an incandescent light includes a rectifying circuit for producing from the AC power line a selected DC voltage. The switch includes a microprocessor powered by this DC voltage for turning on a light at any one of several selected times and for turning off the light at one of an additional corresponding several selected times. A time display is provided for displaying the time as well as for allowing a user to review the programmed status of the switch at any one of several selected times. A signal is generated at each zero crossing of the AC power line which is supplied to the microprocessor. The microprocessor produces output signals which turn on, turn off or dim the light at selected times. The ability of the microprocessor to dim the light further enhances the appearance of human occupancy when the switch is used to simulate occupancy of a vacant building.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.