Pneumatic valve with acoustic alarm for a recipient under pressure

Claim 1

An acoustic alarm arrangement associatable with a pneumatic tire for generating a signal indicating that pressure of gas in the tire decreases from a predetermined magnitude, comprising a housing arranged to be connected with a tire and bounding an inner chamber; a signal element associated with said housing and actuated under the action of a strike; and actuating means operative to strike said signal element in response to a decrease of pressure in the tire, said actuating means including a striking element movable in said inner chamber between an inoperative position in which it is spaced from said signal element and an operative position in which it approaches and strikes the latter, said striking element subdividing said inner chamber into a first compartment located between said striking element and said signal element and communicating with the interior of the tire and a second compartment located at an opposite side of said striking element, said striking element having an inner passage extending between said compartments, said actuating means including a spring located in said second compartment and arranged for urging said striking element to said operative position, said actuating means further including valve means located in said inner passage of said striking element and movable to a closed position when gas at the predetermined pressure flows from the interior of the tire into said second compartment in which closed position said valve means closes said inner passage of said striking element and disconnects said compartments from one another whereby the gas admitted into said one compartment counteracts the force of said spring and retains said striking element in said inoperative position, and said valve means also being movable to an open position when gas under decreased pressure flows from the interior of the tire into said second compartment in which open position said inner passage is opened and said compartments communicate with one another so that gas flows further from said second compartment into said first compartment whereby gas pressures in said compartments become substantially equalized and said spring moves said striking element to said operative position.