Patent ID: 8651828

Claim:
A vacuum pump for evacuating a system to a pressure below ambient, atmospheric pressure, said vacuum pump having a main body, an inlet arrangement, and a combined debris catcher and positive pressure relief valve to relieve pressure above ambient, atmospheric pressure to the ambient air, said inlet arrangement having first and second ports and said combined debris catcher and positive pressure relief valve being selectively movable between a sealing position with said inlet arrangement and an open position, said combined debris catcher and positive pressure relief valve in said sealing position forming a closed flow path from the first port of the inlet arrangement connectable in fluid communication with the system to be evacuated through the combined debris catcher and positive pressure relief valve and out through the second port of the inlet arrangement into the main body of the pump, said combined debris catcher and positive pressure relief valve in said open position exposing said flow path to ambient air, said combined debris catcher and positive pressure relief valve being spring biased toward said sealing position wherein in one mode of operation with the combined debris catcher and positive pressure relief valve in said sealing position, the main body of the pump draws fluid at pressure below said ambient, atmospheric pressure through the first port of the inlet arrangement from the system through the combined debris catcher and positive pressure relief valve and out through the second port of the inlet arrangement into the main body of the pump and wherein in another mode of operation with the fluid entering the first port at pressure above ambient, atmospheric pressure the combined debris catcher and positive pressure relief valve is moved to said open position to vent the fluid entering the first port at pressure above ambient, atmospheric pressure to the ambient air upstream of the second port wherein said combined debris catcher and positive pressure relief valve in said sealing position includes a tube to collect therein debris passing along said closed flow path from the first port of the inlet arrangement connectable in fluid communication with the system to be evacuated through the combined debris catcher and positive pressure relief valve including through the tube therein and out through the second port of the inlet arrangement into the main body of the pump, said tube extending between an open upper end and a closed lower end with said spring biasing said upper end toward said sealing position with said inlet arrangement.