Short range trapped miner locator

US4491971A · kind A · utility

Assignee

• The United States of America, as represented by The Secretary of The Interior · US

Inventors

• William E. Webb · Tuscaloosa, US
• Ronald H. Church · Birmingham, US

Key dates

• Filing date: Mar 8, 1983
• Grant date: Jan 1, 1985
• Expiry date: Mar 8, 2003

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S1/68
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A short range, low power, radio wave transmitter which acts as a miner locator. The transmitter is incorporated with the cap lamp circuitry for the miner. It utilizes the same self-contained power source and its wire connection thereto acts as the transmitter's antenna. No action on the miner's part is necessary in order to begin the transmission which may be on a specific identifying frequency for each miner. An electronic crowbar circuit may be used to conserve power for the transmitter by cutting off power to the cap lamp should the voltage across the self-contained power source fall below a preset level. This enables the transmitter to function for several days by reducing the load on the power source.