Patent · US Expired

Occupancy sensor and method of operating same

US5640143A · kind A · utility

121Cited by
44References
55Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 6, 1995
Grant dateJun 17, 1997
Priority date
Expiry dateFeb 6, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S250/01
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An occupancy sensor that provides improved performance by the inclusion of a microprocessor that controls the sensing transducers and processes the received signal to optimize desired detection performance. The occupancy sensor includes a quadrature detection technique and automatic sensitivity adjustment that reduce false detection caused by air flow, hallway traffic and other noise sources. A fault detection method executed periodically detects fault conditions in the sensor or sensing area caused by component failure or obstructions in front of the sensor. Transmitter power is varied depending on the size of the desired coverage area. Since various ambient parameters such as line voltage, light level, and temperature may be easily and usefully monitored, the microprocessor may use these variables to make intelligent decisions in controlling electrical loads, such as building lighting and ventilation.

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