| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a vane pump having the excellent projection property of vane in the inner peripheral surface direction of a cam ring in an area between the final end of an intake area and the start end of a discharge area. <P>SOLUTION: This vane pump is formed so that a first and second intake side back pressure grooves 25 and first and second discharge side back pressure grooves 28 can be formed in the opposed inner surfaces of a rear body 3 and a pressure plate. A first intake side opening 18 leading a pump intake pressure therein is formed in the inner surface of the rear body, and a second intake side opening leading a pressure lower than the pump intake pressure is formed in the inner surface of the pressure plate. The length of the final point 18b of the first intake side opening relative to the final point 23b of the second intake side opening is made shorter at an angle of approximately 10° in the circumferential direction, and the tip parts of the vanes are pulled out beforehand by acting a low pressure near a negative pressure on the second intake side opening side (23b side) on the tip parts of the vanes immediately after the final point 18b to improve the projection property of the vanes in the discharge area B. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
