Infrasonic switch
US4800293A · kind A · utility
Inventor
Key dates
| Filing date | Apr 16, 1987 |
| Grant date | Jan 24, 1989 |
| Priority date | — |
| Expiry date | Apr 16, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/94
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Infrasonic switch device to actuate an alarm in response to detection of infrasonic energy, including a multi-position switch circuit having a "standby" or "reset" position responsive to infrasonic signals, an infrasonic detection circuit to detect and pass selected levels of infrasonic energy, a trigger circuit to actuate an alarm such as a light or a buzzer for a predetermined time upon detection of the selected levels of infrasonic energy, and a timing circuit to permit actuation of the alarm for a predetermined time when the multi-position switch is in the "standby" or "reset" mode. The device also includes delay switching angle circuitry to consume the power to operate the device's internal components utilizing only selected portions of both the positive and negative AC power cycle and to utilize the balance of each AC cycle to operate the alarm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.