Pneumatic actuator

Abstract

A pneumatic actuator adapted for placement between a pair of spaced members for controlling relative movement between said members is formed of two different hardness plastic materials and includes a rigid base and a flexible top member forming an internal air chamber therebetween. The top member is movable between collapsed and expanded positions by pressurized air introduced into the internal chamber for relative movement of the spaced members. The base has a sidewall terminating in a peripheral edge on which the top member is sealingly secured by a hot welded joint. A central portion of the top member has a raised thickened portion which engages one of the spaced members. A stop is located within the internal chamber to maintain the central portion of the top member above the peripheral edge of the base to prevent contact of the spaced member with the sealed joint when the top member is in the collapsed position. An air passage is formed in the base to enable the pressurized air to enter the internal chamber.

Dependencies are inferred from the claim text.