Pressure operated by-pass valve disposed in the cover of a feed pump for reverse flow

摘要

A feed pump having a pair of gears that mesh with each other and are driven to rotate in a pump chamber. The gears supply a feed medium from an intake chamber connected to a storage tank, along a supply conduit constituted between the end face of the gears and the circumferential wall of the pump chamber. The feed medium is pumped into a pressure chamber, and a bypass conduit that connects the intake chamber to the pressure chamber can be opened by means of a pressure valve disposed in the bypass conduit. The bypass conduit that contains the pressure valve is disposed in a housing cover that closes the housing of the feed pump. The housing cover can be rotated 180 degrees in order to reverse the flow of the fluid medium within the pump.