CONTROL APPARATUS FOR PRESSURIZED GAS/LIQUID SYSTEMS

摘要

CONTROL APPARATUS FOR PRESSURIZED GAS/LIQUID SYSTEMS Control apparatus for purging the pressure in conduits or hoses of pressurized gas/liquid systems such as hot melt foam generating equipment. The control includes a selectively actuable "purge valve" which upon actuation applies an output pressure to reverse the direction of rotation of the motor driving the gas/liquid mixing pump, or alternatively to operate a diverter valve that connects the pump outlet side back to the liquid supply line. Simultaneously, the purge valve cuts off the supply of gas to the mixing pump. The control desirably also includes a selectively actuable "start-up valve" for supplying gas to the gas/liquid mixing pump at higher than normal operating pressure, in order to overcome any internal blockage and prime the pump for starting operation.