Ladas & Parry
Pressure gauge for a pneumatic tire
 A pressure gauge has a pressure-sensing unit including an inner casing that contains a pressure-responsive contact unit, a conductive high-pressure contact unit and a conductive low-pressure contact unit. The pressure-responsive contact unit includes an air impervious and length variable tubular member, and a conductive contact member on one end of the tubular member. In the event of an over-inflated condition, the pressure-responsive contact unit moves in the inner casing to establish physical contact with the high-pressure contact unit, thereby controlling a signal-transmitting unit to transmit a first pressure signal. In the event of an under-inflated condition, the pressure-responsive contact unit moves in the inner casing to establish physical contact with the low-pressure contact unit, thereby controlling the signal-transmitting unit to transmit a second pressure signal. 
B B B
B60C B60C B60C
inventional inventional inventional
Tien-Tsai
Huang