| 摘要 |
The present invention relates to an occupancy detector device that is capable of regulating the on/off status of electrical appliances, such as lights, depending on the presence of people in a given monitored area. The occupancy detector of the present invention relies on the combined functioning of a passive infrared sensor and a sound sensor. Signals from the passive infrared sensor or the sound sensor operate to maintain the electrical appliances in the on state. If no signals are received from these sensors after a predetermined time interval, the off state of the electrical appliances is initiated. Following the initiation of the off state there may be a predetermined grace period during which a sound signal can reinitiate the on state of the electrical appliance. If no sound signal is received during that grace period, only a signal from the passive infrared sensor can subsequently reinitiate the on state. The sound detector of the present invention may be adapted with an "automatic gain control" feature by which background noise is filtered out and does not maintain or initiate the on state of the electrical appliances.
|
