Self-powered wireless tranducer

• Main Authors: MCCLANAHAN, DAVID LEE, TOTTEN, DAVID STANLEY, TARANOWSKI, MICHAEL GEORGE, KINSELLA, JAMES JOSEPH
• Format: Patent
• Language: English; French; German
• Published: 26.07.2000
• Edition: 7
• Subjects: CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; GENERATION; MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC ORINFRASONIC WAVES; MEASURING; PHYSICS; SIGNALLING; TESTING; TESTING STATIC OR DYNAMIC BALANCE OF MACHINES ORSTRUCTURES; TESTING STRUCTURES OR APPARATUS NOT OTHERWISE PROVIDED FOR; TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILARSIGNALS

A self-powered wireless transducer (10) is disclosed for monitoring external physical conditions, such as excessive vibrations in a bearing. The transducer includes an energy conversion source (16), such as a piezoelectric sensor to sense the external physical condition and create a power and characteristic signal that is used to power an RF transmitting circuit (28). A transmitter (30) is provided to transmit signals indicative of the external physical condition, or changes in that physical condition, such as increased vibrations in a bearing to detect bearing faults before a breakdown. In this manner, the monitored machinery can be shutdown in an orderly manner and preventative maintenance can be completed. The self-powered wireless transducer (10) includes an voltage storage device (24) to receive electrical voltage from the piezoelectric sensor (16) and a voltage detector (26) to detect the level of voltage on the voltage storage device (24). Once the voltage detector (26) detects a level of voltage at a predetermined level, an oscillating transmitting circuit (28) is activated for a brief hysteresis period of the voltage detector (26). The information transmitted not only includes any fault detection, it also includes an address of the origin of the transmission.