Combination check and relief valve assembly for a blower manifold

A combination check and relief valve assembly for maintaining a predetermined pressure range at the fluid discharge outlet port of a blower comprising:

• a manifold having an inlet port for receiving the fluid discharge from an outlet port of the blower and a discharge port for discharge of the fluid discharge of the blower, a hollow interior chamber defining a passageway from said inlet port to said discharge port of said manifold for the fluid discharge from the blower and a relief vent port in communication with said interior chamber of said manifold and wherein said manifold has a side channel having an inner open end opening onto said interior chamber thereof and an outer open end which is internally-threaded and wherein said inner end thereof is dimensioned and configured to define a valve seat for a plunger;
• a check valve mounted in said manifold for preventing a backflow of the fluid discharge back through said inlet port upon an excessive pressure drop in said chamber of said manifold;
• and a relief valve mounted in said manifold for releasing and venting the fluid discharge of the blower through said relief vent port in said manifold to the atmosphere upon an excessive pressure buildup in said chamber of said manifold of the fluid discharge received from the blower, said relief valve comprising a plunger movable reciprocately between a normally closed position relative to said relief vent port in which it blocks the fluid discharge through said relief vent port and an open position in which it is spaced from said relief vent port to permit fluid discharge through said relief vent port and a coil spring for normally biasing said plunger into said closed position, and wherein said plunger has an enlarged disc-shaped plunger head having an inner face and an outer face, the latter of which is configured for mating sealing engagement with said valve seat defined by said inner open end of said side channel, and an axially-aligned shaft coupled to said inner face of said plunger head and wherein said coil spring is disposed on said shaft, and relief valve tension adjustment means for adjusting the compressive force applied by said coil spring on said plunger head, said relief valve tension adjustment means comprising a wheel having a threaded periphery for threaded engagement with said internally-threaded outer end of said side channel of said manifold and a central hub having an axially-extending throughbore in which said shaft of said plunger is slidably mounted so that said relief valve coil spring is disposed and extends between said adjustment wheel and said plunger head.