US Patent 7278978 Respiratory vest with inflatable bladder

A vest for a supine human has a one-piece cover with a front panel secured to a bladder coupled to a pulsator operable to subject the vest to repeated pulses of air which applies and releases pressure to the front of the thorax of a person. The bladder has an air chamber and a bottom transverse portion having an air receiving passage and openings to allow air to flow from the air receiving passage into the air chamber. A coil spring within the air receiving passage maintains the air receiving passage open to allow air and air pressure pulses to flow into the air chamber.