Patent ID: 7703702

Claim:
A spray device, comprising: a housing assembly; a pneumatically operated spray control system disposed within the housing assembly and operable to control liquid flow though the spray device, wherein the pneumatically operated spray control system comprises a chamber, a piston movable in the chamber, a spring disposed on a first side of the piston and configured to bias the piston in a first direction, and an air passage leading to a second side of the piston and configured to selectively provide air pressure to bias the piston in a second direction opposite from the first direction, wherein the piston is coupled to a valve member leading to a spray formation section of the spray device; and an umbrella-type check valve disposed through an opening in the housing assembly, wherein the umbrella-type check valve is coupled to an outer wall of the chamber of the housing assembly, wherein the umbrella-type check valve has only a one-way direction of flow out of the housing assembly to enable air to vent from within the housing assembly and to block external liquid from entering the housing assembly, and the umbrella-type check valve is configured to enable the air to vent in response to operation of the pneumatically operated spray control system to control the liquid flow.