Inflatable pocket arrangement for selectively closing a passageway

Claim 1

Apparatus for selectively closing a passageway to the extent necessary to prevent passage of an object or person therethrough, comprising support means defining a passage-way, a pair of inflatable pockets mounted on said support means in opposed relationship on respective sides of the passageway, said pockets being dimensioned and spaced such that when both pockets are fully inflated the passageway is closed, control means for inflating and deflating said pockets including a supply chamber storing a fluid under pressure, an expansion chamber, and respective valved inflation and deflation conduit means for selectively connecting said pockets to said supply and expansion chambers, including valves selectively operable for inflating and deflating said pockets, said inflation conduit means terminating at the pocket end in means for distributing the compressed fluid in a substantially uniform manner over the internal surface of said pockets during inflation first means for detecting whether the object or person is to be permitted to pass through said passageway, second means for detecting the presence of the object or person, and third means for actuating said control means in accordance with the logical response of said first and second means, wherein said third means normally maintains said pocket in the deflated condition, said second means being connected to operate said control means to inflate said pocket in response to detecting the presence of the object or person in the absence of said first means detecting a characteristic indicating permission of the object or person to pass.