Patent ID: 6082983
Filing Date: 2000-07-04
Classification: F01C,F04C

Abstract:
A vane pump comprising:a cam ring housing a rotor joined to a drive shaft, and vanes free to move in said rotor in a radial direction,a body supporting said drive shaft and housing said cam ring,a side plate provided between said body and said cam ring having a first low pressure port in a position corresponding to an intake area of said cam ring and a high pressure port connecting to a high pressure chamber in said body in a position corresponding to a discharge area, said ports being respectively arranged in symmetrical positions,an intake chamber formed inside said body as a gap between the inner circumference of said body and an upper part of the outer circumference of said cam ring, and connected to a low pressure passage for introducing hydraulic fluid from outside said pump,branch passages formed as a gap between the inner circumference of said body and the upper semicircular part of said cam ring, connecting said first low pressure port in said side plate and said intake chamber, anda cover having an end face joined to the open end of said body, and in contact with one face of said cam ring, a second low pressure port in a position corresponding to an intake area of said cam ring and low pressure distributing groove connected to said intake chamber, said groove being formed alongside the upper semicircular area of the outer circumference of said cam ring and extending towards said second low pressure port.