Electric oil pump

Patent metadata

Field	Value
Publication number	US-11920591-B2
Application number	US-201917290305-A
Country	US
Kind code	B2
Filing date	Sep 20, 2019
Priority date	Nov 9, 2018
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

An electric oil pump includes a motor including a motor shaft, a pump assembly including a vane pump driven by the motor to suction and discharge oil, and an inverter to drive the motor. The motor includes a rotor, a stator on a side outward from the rotor in a radial direction, and a motor housing containing the rotor and the stator. The motor housing includes a suction port through which the vane pump suctions oil from outside, and a discharge port through which the vane pump discharges oil to outside. The motor housing includes flat surface portions in a portion of an outer periphery thereof. The suction port and the discharge port are located in a first surface of side surfaces which are the flat surface portions of the motor housing and are parallel or substantially parallel to the axial direction.

First claim

The invention claimed is:

1. An electric oil pump comprising:
a motor including a motor shaft extending along a central axis extending in an axial direction;
a pump assembly including a vane pump which is on one side of the motor in the axial direction and is driven by the motor via the motor shaft to suction and discharge oil; and
an inverter which is on another side of the motor in the axial direction to drive the motor; wherein
the motor includes:
a rotor which is rotatable together with the motor shaft;
a stator which is on a side outward from the rotor in a radial direction that intersects the axial direction; and
a motor housing which houses the rotor and the stator;

the pump assembly includes a pump body that is connected to one side of the motor housing in the axial direction;
the vane pump is housed within the pump body;
the motor housing includes:
a suction port through which the vane pump suctions oil from outside;
a discharge port through which the vane pump discharges oil to outside;
a suction oil passage leads from the suction port to the vane pump; and
a discharge oil passage leads from the vane pump to the discharge port;

the suction oil passage and the discharge oil passage include:
an axial oil passage extending from the pump assembly towards the motor in the axial direction; and
a radial oil passage extending in the radial direction and leading to the suction port or the discharge port;

the axial oil passage overlaps the stator when viewed along the radial direction;
the motor housing includes a flat surface portion in a portion of an outer peripheral shape thereof;
the flat surface includes a first surface which extends in parallel to the axial direction; and
the suction port and the discharge port are located on the first surface.

2. The electric oil pump according to claim 1 , wherein an outer shape of the motor housing is a quadrangular column shape.

3. The electric oil pump according to claim 2 , wherein
the suction oil passage includes a parallel suction oil passage parallel or substantially parallel to the axial direction; and
the discharge oil passage includes a parallel discharge oil passage parallel or substantially parallel to the axial direction.

4. The electric oil pump according to claim 1 , wherein
the suction oil passage includes a radial suction oil passage extending in the radial direction; and
the discharge oil passage includes a radial discharge oil passage extending in the radial direction.

5. The electric oil pump according to claim 2 , wherein
the suction oil passage includes a radial suction oil passage extending in the radial direction; and
the discharge oil passage includes a radial discharge oil passage extending in the radial direction.

6. The electric oil pump according to claim 1 , wherein
the suction oil passage includes an orthogonal suction oil passage orthogonal or substantially orthogonal to the axial direction; and
the discharge oil passage includes an orthogonal discharge oil passage orthogonal or substantially orthogonal to the axial direction.

7. The electric oil pump according to claim 2 , wherein
the suction oil passage includes an orthogonal suction oil passage orthogonal or substantially orthogonal to the axial direction; and
the discharge oil passage includes an orthogonal discharge oil passage orthogonal or substantially orthogonal to the axial direction.

8. The electric oil pump according to claim 1 , wherein
at least a portion of the suction oil passage is between a first side which is a side of the side surfaces which is parallel or substantially parallel to the axial direction and the central axis;
at least a portion of the discharge oil passage is between a second side which is a side of the side surfaces which is parallel or substantially parallel to the axial direction and the central axis; and
the first side is a side different from the second side.

9. The electric oil pump according to claim 8 , wherein the first side and the second side are sides of the first surface.

10. The electric oil pump according to claim 1 , wherein a diameter of the suction port is larger than a diameter of the discharge port.

11. The electric oil pump according to claim 1 , wherein a volume of the suction oil passage is larger than a volume of the discharge oil passage.

12. The electric oil pump according to claim 1 , wherein
the pump assembly is fixed to the motor housing through a bolt; and
the bolt is at a position not overlapping the suction oil passage and the discharge oil passage in the axial direction.

13. The electric oil pump according to claim 12 , wherein three bolts are provided at intervals in a circumferential direction.

Assignees

• Nidec Tosok Corp
• Kyb Corp

Inventors

• Higuchi Koji
• Hashimoto Yutaka
• Maki Yoshiyuki
• Kubo Kohei

Classifications

• F04C2/102 Primary

  the two members rotating simultaneously around their respective axes · CPC title

• F04C11/008 Primary

  Enclosed motor pump units · CPC title

• F04C13/002

  for homogeneous viscous liquids · CPC title

• F04C15/06

  Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet · CPC title

• F04C2210/206

  Oil · CPC title