Vehicle drive device for lubrication a power transmission and cooling a rotating electric machine

Patent metadata

Field	Value
Publication number	US-11114921-B2
Application number	US-201916256643-A
Country	US
Kind code	B2
Filing date	Jan 24, 2019
Priority date	Jan 24, 2018
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

A vehicle drive device is provided with a lubricating path including a first oil pump to pump up an oil stored in the casing by the first oil pump and to supply the oil to the power transmission mechanism for lubricating the power transmission mechanism, and a cooling path that is separated from the lubricating circuit and provided for the rotating electric machine, the cooling path including a second oil pump to pump up the oil stored in the casing by the second oil pump to supply the oil exclusively to the rotating electric machine for cooling the rotating electric machine, the second oil pump is an electric oil pump, and the cooling path is provided with an oil cooler cooling the oil to be supplied to the rotating electric machine.

First claim

What is claimed is:

1. A vehicle drive device comprising:
a rotating electric machine;
a power transmission mechanism transmitting a rotational drive power between the rotating electric machine and a plurality of wheels;
a casing housing the rotating electric machine and the power transmission mechanism, the vehicle drive device supplying an oil stored in the casing to the power transmission mechanism and the rotating electric machine to lubricate the power transmission mechanism and to cool the rotating electric machine;
a lubricating path including a first oil pump to pump an oil stored in the casing by the first oil pump and to supply the oil to the power transmission mechanism for lubricating the power transmission mechanism;
a cooling path separated from the lubricating path and provided for the rotating electric machine, the cooling path including: (i) a second electric oil pump to pump the oil stored in the casing by the second electric oil pump to supply the oil exclusively to the rotating electric machine for cooling the rotating electric machine, (ii) an oil cooler cooling the oil to be supplied to the rotating electric machine, and (iii) a cooling pipe, which is located downstream of the oil cooler and is arranged vertically above the rotating electric machine in a housing space of the casing, into which at least a portion of the oil discharged from the oil cooler and from the second electric oil pump is introduced, and the cooling pipe includes a first discharge hole and a second discharge hole that discharges the introduced oil to the rotating electric machine; and
a controller configured to control the second electric oil pump to supply oil to the rotating electric machine only when a temperature of a stator core of the rotating electric machine is greater than a predetermined temperature threshold value.

2. The vehicle drive device according to claim 1 , wherein the lubricating path includes a catch tank storing at least a portion of the oil discharged from the first oil pump and ejecting the stored oil to the power transmission mechanism.

3. The vehicle drive device according to claim 1 , further comprising a rotor disposed in the rotating electric machine rotatably supported by a cylindrical rotor shaft penetrating through and integrally fixed to the rotor such that at least a portion of the oil discharged from the second electric oil pump is introduced into an inside of the rotor shaft, wherein
the cooling path includes a radial oil passage formed in the rotor shaft to eject the oil introduced into the inside of the rotor shaft to the rotating electric machine.

4. The vehicle drive device according to according to claim 1 , further comprising a rotor disposed in the rotating electric machine rotatably supported by a cylindrical rotor shaft penetrating through and integrally fixed to the rotor such that at least a portion of the oil discharged from the second electric oil pump is introduced into an inside of the rotor shaft, wherein
the cooling path includes (i) a supply oil passage to supply the oil discharged from the second electric oil pump to an oil introduction port of the cooling pipe, (ii) a branch oil passage branched from the supply oil passage to introduce a portion of the oil supplied to the supply oil passage to the inside of the rotor shaft, and (iii) a radial oil passage formed in the rotor shaft to eject the oil introduced into the inside of the rotor shaft to the rotating electric machine.

5. The vehicle drive device according to claim 4 , further comprising an orifice located between the supply oil passage and the oil introduction port of the cooling pipe such that a cross-sectional area in flow-passage is smaller than in the supply oil passage.

Assignees

• Toyota Motor Co Ltd
• Aisin Aw Co
• Aisin Corp

Inventors

• Ito Eiji
• Takagi Kiyonori
• Jinnai Naoya
• Kato Takahiro

Classifications

• H02K9/19 Primary

  for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil · CPC title

• F16H57/0471

  Bearing · CPC title

• F16H57/0441

  Arrangements of pumps · CPC title

• F16H57/0436

  Pumps · CPC title

• F16H57/042 Primary

  Guidance of lubricant · CPC title