Deflation control valve for a sphygmomanometer has a control knob controlling the gas flow rate in which gas passes through the diaphragm port and between the closure disc face and diaphragm to control pressure drop in the chamber

摘要

A manually operable control knob (8) bearable on a platen (5) is used for controlling the rate of gas flow through a control valve. Gas passes from the valve chamber through a diaphragm port (4A) and between the closure disc face and diaphragm (4) to the exhaust such that pressure of the pressure chamber drops in a controlled manner. A cam and lever device reversibly urges the platen into closing position. A displacement device amplifies the movement of the knob. A small groove compensates for falling pressure in the pressure chamber and controls the rate of change of pressure in the chamber.