Kyb Corporation

Fumiyasu Kato

Koichiro Akatsuka

Tomoyuki Fujita

Masamichi Sugihara

Hiroki Gomi

A vane pump includes a rotor having slits, vanes received in the slits, a cam ring having an inner circumference cam face with which the vanes are brought into sliding contact, a side member, pump chambers formed by the rotor, the cam ring, and adjacent vanes, and back pressure chambers formed in the slits by the vanes. In the vane pump, the side member is provided with a back pressure opening portion opening at a sliding-contact surface in sliding contact with the rotor, the back pressure opening portion being configured to communicate with the back pressure chambers, and a protruding opening portion protruding along the rotating direction of the rotor from an end portion of the back pressure opening portion on the communication-finishing side. An inner-side inner circumferential surface of the protruding opening portion is connected to an inner-side inner circumferential surface of the back pressure opening portion.

Vane pump having a side member including a triangular-shaped protruding opening portion in communication with a back pressure opening portion for preventing wear of an inner circumference cam face

A vane pump used as a fluid pressure source includes: a rotor that is rotationally driven; a plurality of vanes that are inserted into the rotor in a freely slidable manner; a cam ring at which tip-end portions of the vanes slides as the rotor rotates; a pump chamber that is defined between the adjacent vanes; a suction port that guides working fluid to the pump chamber; a discharge port through which the working fluid discharged from the pump chamber is guided; a groove-like notch that extends from an opening edge of the discharge port in an opposite direction from rotation direction of the rotor, and the notch has a gradient-changing portion at which a rate of change of opening area is decreased in the rotation direction of the rotor.

Vane pump

A vane pump includes a rotor, vanes, pump chambers, a suction port, and a discharge port. The side member has a first transition section and a second transition section. The first transition section is a section from an end point of the suction port to a start point of the discharge port. The second transition section is a section from an end point of the discharge port to a start point of the suction port. An angle between the start point and the end point of the suction port is set such that a pressurizing timing is offset from a depressurizing timing. The pressurizing timing is a timing at which one pump chamber starts to communicate with the discharge port from the first transition section, and the depressurizing timing is a timing at which another pump chamber starts to communicate with the suction port from the second transition section.

Variable displacement vane pump

A variable displacement vane pump includes: a rotor to be rotatively driven; a plurality of vanes slidably housed in the rotor; a cam ring allowed of eccentric with respect to a center of the rotor, the cam ring having an inner circumferential cam surface in sliding contact with a distal end portion of the vane; a pump chamber defined by the adjacent vanes, the rotor, and the cam ring; a suction port to guide hydraulic fluid to be suctioned to the pump chamber; and a discharge port to guide hydraulic fluid to be discharged from the pump chamber. An outer circumference of an opening portion of the suction port is formed so as to be positioned along the inner circumferential cam surface of the cam ring or at an outside of the inner circumferential cam surface regardless of eccentricity of the cam ring with respect to the rotor.

A vane pump includes: a rotor; vanes; a cam ring; pump chambers; a suction port; a discharge port; back-pressure chambers; a discharge-side back pressure port configured to guide working fluid that is discharged from the discharge port to the back-pressure chambers; and suction-side back pressure ports configured to guide the working fluid to the back-pressure chambers. The suction-side back pressure ports are formed to be divided into a low-pressure port and a high-pressure port, the low-pressure port being configured to guide the working fluid in the suction port to the back-pressure chambers, and the high-pressure port being configured to guide the working fluid that is discharged from the discharge port to the back-pressure chambers. The high-pressure port is arranged at the forward-side of the low-pressure port in rotating direction of the rotor.

A variable displacement vane pump includes a rotor, vanes, a cam ring, pump chambers, a suction port, a discharge port, back pressure chambers, a plate that has a sliding contact surface and a penetrating hole, a suction-side back pressure port being configured to guide the working fluid in the suction port to the back pressure chambers in a suction section, a discharge-side back pressure port being configured to guide the working fluid that is discharged from the discharge port to the back pressure chambers in a discharge section, an additional groove provided on the sliding contact surface so as to extend from between the discharge-side back pressure port and the penetrating hole to between the suction-side back pressure port and the penetrating hole, and a connection groove that communicates the additional groove with the suction-side back pressure port.

Variable displacement vane pump having connection groove communicating with suction-side back pressure port thereof

In a variable capacity type vane pump in which a cam ring pivots, a discharge port is so formed that an absolute value of a difference between a discharge port start edge line inclination angle and a discharge port end edge line inclination angle is larger than a vane angle.

Variable capacity type vane pump

A variable displacement vane pump includes: an adapter ring (a cam ring housing member) that defines a first fluid pressure chamber and a second fluid pressure chamber relative to an outer periphery of a cam ring, the cam ring being moved relative to a rotor by a differential pressure between the first fluid pressure chamber and the second fluid pressure chamber; a seal housing groove formed in an inner periphery of the adapter ring; and a slipper seal which is inserted into the seal housing groove and with which an outer periphery of the cam ring comes into sliding contact when the cam ring moves, whereby the slipper seal partitions the first fluid pressure chamber from the second fluid pressure chamber, wherein the slipper seal is formed in a thin plate shape having a square cross-section.

A variable capacity type vane pump with a first fluid pressure chamber and a second fluid pressure chamber provided at opposite sides of a pivot point of a cam ring includes a control valve for controlling a drive pressure of working fluid introduced from a pump chamber to the second fluid pressure chamber, a suction pressure of the working fluid sucked into the pump chamber is constantly introduced to the first fluid pressure chamber, and the cam ring pivots in a direction to decrease a discharge capacity due to a pressure in the pump chamber acting on an inner peripheral cam surface during an operation to reduce the drive pressure, whereas the cam ring pivots in a direction to increase the discharge capacity during an operation to increase the drive pressure.

In a variable capacity vane pump in which a discharge capacity of a pump chamber is varied by varying an amount of eccentricity of a cam ring relative to a rotor, a port inner wall surface that extends around an inner peripheral cam surface of the cam ring when the cam ring moves in a direction for increasing the amount of eccentricity of the cam ring relative to the rotor is formed on an intake port.

Growing community of inventors

Aichi, Japan

Fumiyasu Kato