VARIABLE DISPLACEMENT PUMP

PROBLEM TO BE SOLVED: To suppress the wear of a housing.SOLUTION: A variable displacement pump 1 is provided that has a piston 16 in a cylinder block 14 rotating integrally with a rotary shaft 20, the piston 16 reciprocating at a stroke corresponding to the inclination angle of a swash plate 30, and that sucks and discharges working fluid by the reciprocation of the piston 16. The variable displacement pump 1 comprises a piston part 58 which pressurizes the swash plate 30 to control the inclination angle of the swash plate 30, and a roller 32 which is arranged between the swash plate 30 and the piston part 58 and is pressurized to the side of the swash plate 30 by the piston part 58. The piston part 58 pressurizes the roller 32 to adjust the inclination angle of the swash plate between the maximum inclination angle and the minimum inclination angle, and when the inclination angle is an intermediate inclination angle at which the discharge volume of the working fluid is intermediate volume between the maximum and the minimum volume, a contact P between the piston part 58 and the roller 32 is located at a central portion 58aof an end face.SELECTED DRAWING: Figure 1 【課題】ハウジングの摩耗を抑制する。【解決手段】回転軸２０と一体的に回転するシリンダブロック１４内のピストン１６が斜板３０の傾角に応じたストロークで往復動することで、作動流体の吸入および吐出をおこなう可変容量型ポンプ１であって、斜板３０を押圧することで斜板３０の傾角を制御するピストン部５８と、斜板３０とピストン部５８との間に配置されており、ピストン部５８により斜板３０側へ押圧されるコロ３２と、を備え、ピストン部５８は、コロ３２を押圧して、最大傾角と最小傾角との間で斜板の傾角を調整し、斜板３０の傾角が、作動流体の吐出容量が最大と最小との中間となる中間傾角であるときに、ピストン部５８とコロ３２との接点Ｐは、ピストン部５８の端面５８ａの中央部分５８ａ１に位置している。【選択図】図１