Patent ID: 7566013

Claim:
A system for failsafe controlled dispensing of a liquid material comprising: a housing having an inlet, an outlet, and an intermediate portion extending therebetween, said intermediate portion having formed therein an admission port for admission of the liquid material therethrough; a control valve disposed in said intermediate portion for directing a pressurized fluid stream entering said inlet, said control valve being selectively disposed between at least open and closed configurations; and, a response valve disposed in a flow path between said control valve and said outlet, said response valve being actuable between active and inactive configurations responsive to said control valve direction of said pressurized fluid stream, said response valve being maintained in said active configuration by delivery of said pressurized fluid stream to said open control valve; wherein admission of the liquid material into said housing is enabled by said response valve being in said active configuration; wherein said response valve includes a displaceable assembly displaceable between active and inactive positions relative to said housing to assume said respective active and inactive configurations, said displaceable assembly being resiliently biased to one of said inactive and active positions; wherein said displaceable assembly includes a spring loaded piston member disposed in axially displaceable manner within a receiving compartment in said housing intermediate portion, said piston member having an interface end and a mixing chamber extending axially therefrom, said mixing chamber being in open communication with said admission port when said displaceable assembly is disposed in said active position; and, wherein said intermediate portion of said housing has formed therein a plurality of vent ports offset from said admission port, and said displaceable assembly includes a plurality of seal members disposed on said piston member axially displaced one from the other to isolate said vent ports one from the other in sealed manner when said displaceable assembly is disposed in said inactive position.