Patent attributes
An apparatus for failsafe control of liquid material passage through a line is provided. The apparatus includes a dispensing control unit for coupling to the line, which includes a housing having an inlet, an outlet, and a conduction port extending therebetween for selectively passing the liquid material received from the line therethrough. A control port is disposed in the housing to direct a flow path of at least a portion of a pressurized fluid stream received thereby. A response valve portion also disposed in the housing is reconfigurable between first and second states responsive to the pressurized fluid stream directed thereto, such that in the first state it seals the conduction port against passage of the liquid material, and in the second state opens the conduction port for passage of the liquid material. The response valve portion is resiliently biased to the first state.