Device for indicating loss of tire air pressure

Claim 1

IN A DEVICE FOR INDICATING A LOSS IN TIRE AIR PRESSURE ON A VEHICLE COMPRISING: (A) A BODY MEMBER HAVING (B) AN AIR INLET ORIFICE LEADING TO (C) A CYLINDER FORMED THEREIN; (D) MEANS FOR CONNECTING SAID AIR INLET ORIFICE TO THE VALVE STEM OF A TIRE, (E) A PISTON MOUNTED IN SAID CYLINDER AND HAVING (F) A ROD EXTENDING AXIALLY THEREFROM, (G) MEANS FOR INTRODUCING AIR INTO SAID AIR INLET ORIFICE TO ACTUATE SAID PISTON AND INFLATE A TIRE THROUGH SAID CONNECTING MEANS, (H) A BUSHING ADJUSTABLY MOUNTED IN SAID CYLINDER AND THROUGH WHICH SAID ROD FREELY EXTENDS, (I) AND INSULATOR MEMBER LOCATED ON SAID ROD, (J) A CONTACT MEMBER LOCATED ON SAID ROD, (K) A SIGNAL TRANSMITTER MOUNTED IN SAID BODY MEMBER HAVING A CONTACTOR MEMBER THEREON, (1) A COIL SPRING MOUNTED ON SAID ROD BETWEEN SAID PISTON AND SAID BUSHING URGING SAID PISTON AND ROD THEREON TOWARD SAID AIR INLET ORIFICE TO BRING SAID CONTACT IN CONTACT WITH SAID CONTACTOR TO THEREBY ENERGIZE SAID TRANSMITTER UPON A DECREASE IN PRESSURE ON SAID PISTON, SAID TRANSMITTER BEING DEENERGIZED AS A RESULT OF SAID INSULATOR ON SAID ROD CONTACTING SAID CONTACTOR DUE TO AN INCREASE IN AIR PRESSURE UPON SAID PISTON, AND (M) MEANS FOR MOUNTING SAID BODY MEMBER ON THE WHEEL OF A VEHICLE.