Variable displacement vane pump

Abstract

A vane pump includes: a rotor connected to a driving shaft; a plurality of vanes provided so as to be capable of reciprocating in a radial direction with respect to the rotor; a cam ring having a cam face on which a tip-ends of the vanes slide with the rotation of the rotor, the cam ring being provided so as to be capable of being made eccentric with respect to the rotor; a second pump body configured to accommodate the cam ring; and a spring interposed between the cam ring and the second pump body in a compressed state, the spring being configured to bias the cam ring in the direction in which the amount of eccentricity with respect to the rotor is increased. The cam ring and the second pump body have seating surfaces on which the spring is seated and grooves formed in the seating surfaces.

1 . A variable displacement vane pump comprising:
 a rotor connected to a driving shaft;   a plurality of vanes provided so as to be capable of reciprocating in a radial direction with respect to the rotor;   a cam ring having an inner circumferential surface on which tip-ends of the vanes slide with rotation of the rotor, the cam ring being provided so as to be made eccentric with respect to the rotor;   an accommodating member configured to accommodate the cam ring; and   a biasing member interposed between the cam ring and the accommodating member in a compressed state, the biasing member being configured to bias the cam ring in a direction in which an amount of eccentricity with respect to the rotor is increased; wherein   at least one of the cam ring and the accommodating member has a seating surface on which the biasing member is seated and a groove formed in the seating surface.   
     
     
         2 . The variable displacement vane pump according to  claim 1 , wherein
 the groove is a jig insertion groove into which a jig for compressing the biasing member is inserted, the groove being formed at a position facing the biasing member.   
     
     
         3 . The variable displacement vane pump according to  claim 1 , wherein
 the cam ring has a main body portion and a lever portion provided with the seating surface, the main body portion being formed with the inner circumferential surface on which the tip-ends of the vanes slide, the lever portion being formed so as to extend from the main body portion in the radial direction.   
     
     
         4 . A variable displacement vane pump comprising:
 a rotor connected to a driving shaft;   a plurality of vanes provided so as to be capable of reciprocating in a radial direction with respect to the rotor;   a cam ring having an inner circumferential surface on which tip-ends of the vane slide with rotation of the rotor, the cam ring being provided so as to be capable of being decentered with respect to the rotor;   an accommodating member configured to accommodate the cam ring;   a biasing member interposed between the cam ring and the accommodating member in a compressed state, the biasing member being configured to bias the cam ring in a direction in which an amount of eccentricity with respect to the rotor is increased; and   a seating member on which the biasing member is seated, the seating member being provided between the biasing member and the cam ring, wherein   the seating member has a contacting portion, a seating portion on which the biasing member is seated, and an engagement portion, the contacting portion being configured to come into contact with the cam ring and the engagement portion being configured to engage with a jig for compressing the biasing member, and   the jig, which is engaged with the engagement portion, as well as the cam ring and the accommodating member are configured so as not to come into mutual contact in a state in which the contacting portion is in contact with the cam ring.   
     
     
         5 . (canceled)