# US 11,306,718 B2 · Vane pump

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- Number: US 11,306,718 B2
- Document ID: US11306718B2
- Status: Granted
- Kind: B2
- Application number: 16/345,972
- Filed: 2017-10-30
- Published: 2019-09-05
- Granted: 2022-04-19
- Earliest claimed: 2016-11-03
- Assignees: Taiho Kogyo Co., Ltd.; Toyota Jidosha Kabushiki Kaisha
- Applicants: TAIHO KOGYO Co., Ltd.; Toyota Jidosha Kabushiki Kaisha
- Inventors: Yuji Suzuki; Akihiro Uto; Naoyuki Miyara; Hiroki Hara; Shinsuke Kiyomiya; Akira Fujii
- Web page: https://patentgrep.com/patent/US11306718B2

## CPC

- F04C 18/344: with vanes reciprocating with respect to the inner member
- F04C 18/3441: {the inner and outer member being in contact along one line or continuous surface substantially parallel to the axis of rotation}
- F01C 21/108: {with an axial surface, e.g. side plates}
- F04C 25/02: for producing high vacuum (sealing arrangements F04C27/00; silencing F04C29/06)
- F04C 29/00: Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C 29/0028: {Internal leakage control}
- F04C 29/12: Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet
- F04C 29/124: {with inlet and outlet valves specially adapted for rotary or oscillating piston pumps}
- F01C 21/0809: {Construction of vanes or vane holders}
- F04C 2210/22: gaseous, i.e. compressible
- F04C: ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS (engines F03C); ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F01C: ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES (internal-combustion aspects F02B53/00, F02B55/00)

## Abstract

A vane pump includes a housing, a rotor, a vane and a reed valve. A position at which the sliding direction of the vane with respect to the rotor is inverted from outward to inward is defined as a reference position, and a section of the pump chamber on the discharge hole side with respect to the reference position is defined as a discharge section. A pressure relief groove is disposed in a portion of the bottom wall portion corresponding to the discharge section with a clearance secured between the peripheral wall portion and the pressure relief groove. When the vane overlaps the pressure relief groove, a pair of the working chambers communicate with each other via the pressure relief groove.

## Claims

### Claim 1

A vane pump including:
a housing disposed on a cover member of an engine, having a tubular peripheral wall portion and a bottom wall portion which is disposed at one end of the peripheral wall portion in an axial direction and in which a discharge hole that communicates with an internal space of the cover member is provided to open, and defining a pump chamber communicating with the discharge hole inside the housing;
a rotor that is disposed in the pump chamber and that is rotatable about a rotational axis of the rotor along with rotation of a camshaft of the engine;
a vane disposed so as to be slidable with respect to the rotor in a radial direction, the vane partitioning the pump chamber into a plurality of working chambers and causing capacities of the working chambers to increase and decrease along with rotation of the rotor; and
a reed valve that opens and closes the discharge hole to allow air compressed in the working chambers and lubricating oil to be intermittently discharged to the internal space of the cover member,
wherein a pressure relief groove that is continuous with the discharge hole is disposed in an inner surface of the bottom wall portion, a clearance is provided between an inner surface of the peripheral wall portion and the pressure relief groove such that a radial outer edge of the pressure relief groove is disposed apart from the inner surface of the peripheral wall portion by the clearance over an entire length in an extension direction of the pressure relief groove,
wherein a pair of the working chambers on both sides of the vane in a rotational direction communicate with each other via the pressure relief groove when the vane overlaps the pressure relief groove during forward rotation of the rotor,
wherein the pressure relief groove is arranged on an outer side of the rotor in the radial direction of the rotor
wherein the pressure relief groove extends in a circumferential direction about the rotational axis of the rotor, and
wherein a position at which a sliding direction of the vane with respect to the rotor is inverted from outward in the radial direction to inward is defined as a reference position, a line extending through the reference position and the rotational axis of the rotor is defined as a division line, and an angle about the rotational axis of the rotor with respect to the division line is defined as a center angle, such that the reference position is at the center angle of 0°, and the pressure relief groove extends between a first side and a second side in the rotational direction with reference to a position directly below the rotational axis of the rotor at the center angle of 90°.

### Claim 2

The vane pump according to claim I. wherein the cover member is a chain cover that houses a timing chain that transfers a rotational drive force to the camshaft.