Dual stage air compressor

Claim 1

A dual stage throttled, portable air compressor, comprising: a cylinder, a piston reciprocal within said cylinder, an electric motor, means interconnecting said motor and said piston for producing reciprocal movement of said piston, a housing in fluid communication with said cylinder, intake and release valves in said housing for controlling air flow into and out of said cylinder upon reciprocal movement of said piston, a throttling valve, operative when actuated to limit air flow to said intake valve, said throttling valve being actuated in response to outlet air pressure from said release valve above a predetermined level, said housing comprising a cylinder head supported on said cylinder and a valve housing supported on said cylinder head, said intake and release valves being cooperative with intake and release valve seats respectively in said cylinder head and said throttling valve being supported in said valve housing, and a cap forming one end of said valve housing, said cap having first and second openings therein, and a boss thereon forming a seat for said throttling valve, said first and second openings in said cap being in fluid communication with said intake valve for admitting inlet air to said cylinder, said throttling valve being operable when actuated to close said first opening to limit the flow of air to said intake valve, thereby reducing the charge of air in said cylinder.