Lube oil pump with relief valve

摘要

An oil pump has a split frame with the pump mechanism situated in a chamber in one of the frames or between the split frames. An inlet conduit extends from an inlet port to the low pressure side of the pump and an outlet conduit extends from the high pressure side of the pump to an outlet port. An excess pressure relief path is provided to permit fluid flow from the outlet conduit to the inlet conduit when the outlet conduit pressure exceeds the inlet conduit pressure by a predetermined difference. This is accomplished by providing a bypass channel formed in one frame and fluidly intersecting the outlet conduit, and a valve cavity formed in the other frame and fluidly intersecting the bypass channel and the inlet conduit. Valve means are situated in the valve cavity for isolating the bypass channel from the inlet conduit during normal pressure differences between the inlet and outlet conduits. Upon the occurrence of excess pressure in the outlet conduit, the valve opens to permit fluid flow from the outlet conduit to the inlet conduit.