Low tire pressure warning system

Claim 1

A low tire pressure warning system for a trailer having tandem axles comprising: a frame for supporting the body of a trailer, tandem axles equipped with normally inflated pneumatic tires, suspension means for said axles including a walking beam that is pivoted on the frame for tilting movement in opposite directions from a normal position in accordance with the deflation of a tire of either one of said axles, signal means for indicating that one of said tires doesn't have enough air, a signal operating switch in circuit with said signal means, actuating means for said signal operating switch comprising a plurality of actuator rods that extend laterally with respect to the longitudinal axis of said frame, said actuator rods extend across the width of said frame and have their ends journaled in bearings, each of said actuator rods being associated with one of the axles, said actuator rods being mounted to said frame so that they may pivot about their longitudinal axis, first means on said actuator rods connected to said axles whereby said actuator rods pivot a predetermined arc in response to the axle dropping downwardly due to loss of air pressure in the tire, second means on said actuator rods connected to said signal operating switch whereby when said actuator rods pivot a predetermined arc in response to the axle dropping downwardly the switch will close completing the circuit and operate the signal means, and said first means on said actuator rode comprises a pair of arms located adjacent the opposite ends of said actuator rods that extend radially outward from the actuator rods and toward the front end of the trailer with the forward end of said arms normally being positioned vertically above the respective axles, a link chain is normally stretched taut between the end of said arms and said axle with its respective ends secured to said members.