Bacon & Thomas
Tire pressure alarm system with centrifugal force-controlled power switch
 A tire pressure alarm system includes a tire pressure sensor and radio transmitter circuit, that detects the air pressure of a tire and sends the detected tire pressure value to a radio receiver and alarm circuit by radio transmission communication. A radio receiver and alarm circuit receives the radio signal from a tire pressure sensor and radio transmitter circuit having a tire pressure sensor and radio transmitter circuit that has a power supply circuit. The power supply circuit includes a power source and a power switch, and the power switch has first and second metal contacts respectively connected to the positive and negative terminals of the power source. A metal spring member has a fixed end connected to a first metal contact and a free end mounted with a metal weight and is spaced from a second metal contact. When the tire is rotated at a speed over a predetermined level, a centrifugal force is produced forcing the metal weight at the free end of the metal spring member to contact with the second metal contact. The power switch is switched on automatically and enables the tire pressure sensor and radio transmitter circuit to detect the tire pressure of the tire and sends the detected tire pressure value to the radio receiver and alarm circuit by radio transmission signals. 
B B
B60C B60C
inventional inventional
Tien-Tsai
Huang