Positive-displacement pump i.e. single-stroke sliding vane pump, for servo-steering device of motor vehicle, has front surface with wall surface deformed so that gap is formed or enlarged, through which fluid is flown from work cell

摘要

The pump has a pumping pressure opening (11), and a housing supporting a rotor set, which is formed from a rotor and locking units (4). A work space is divided into work cells (8) by the locking units and laterally limited by front surfaces (9a). One of the front surfaces has a wall surface (13) that is deformable depending on pressure of a fluid in the cells such that a gap (18) is formed or enlarged between an element e.g. rotor, locking units and cam ring, limiting the work cells and the wall surface during increasing of the pressure. The fluid is flown from the work cell through the gap.