US-12623525-B2 - Unit

US12623525B2US 12623525 B2US12623525 B2US 12623525B2US-12623525-B2

Abstract

A unit includes: a rotating electrical machine; an inverter located in an outer periphery of the rotating electrical machine; a first gear connected downstream of the rotating electrical machine; a second gear to mesh with the first gear; a third gear connected downstream of the second gear via a shaft; and a fourth gear to mesh with the third gear. The shaft has a portion that overlaps a stator of the rotating electrical machine when viewed in a radial direction, and the inverter has a portion that overlaps the second gear when viewed in an axial direction.

Inventors

Atsushi Maeda
Minoru SHOICHI
Hiroki Uehara
Akira Suwabayashi

Assignees

JATCO LTD

Dates

Publication Date: 20260512
Application Date: 20230512
Priority Date: 20220613

Claims (3)

1 . A unit comprising: a rotating electrical machine; an inverter located in an outer periphery of the rotating electrical machine; a first gear connected downstream of the rotating electrical machine; a second gear to mesh with the first gear; a third gear connected downstream of the second gear via a shaft; a fourth gear to mesh with the third gear; and a differential gear connected downstream of the fourth gear, wherein the shaft has a portion that overlaps a stator of the rotating electrical machine when viewed in a radial direction, the inverter has a portion that overlaps the second gear when viewed in an axial direction, the rotating electrical machine, the first gear, the fourth gear, and the differential gear are disposed on a first axis, the second gear and the third gear are disposed on a second axis, and the differential gear protrudes in a direction away from the stator with respect to the fourth gear.
2 . The unit according to claim 1 , wherein when viewed in a predetermined direction, the shaft has a portion that overlaps the stator, and the shaft and the inverter are offset from each other.
3 . The unit according to claim 1 , wherein a bearing that supports the shaft overlaps the differential gear when viewed in the radial direction.

Description

TECHNICAL FIELD The present invention relates to a unit. BACKGROUND ART Patent Document 1 discloses a vehicle drive device including a counter gear mechanism that reduces a speed. The vehicle drive device transmits output torque of a rotating electrical machine to a pair of wheels via a pair of output members to run a vehicle. PRIOR ART DOCUMENT Patent Document Patent Document 1: WO2021/131204 SUMMARY OF INVENTION The rotating electrical machine can be used in combination with a power transmission mechanism such as a reduction mechanism, an acceleration mechanism, and a transmission mechanism. However, when an attempt is made to provide the rotating electrical machine and the power transmission mechanism separately rather than as a unit, an efficient layout cannot be implemented, and as a result, an overall size may become larger. Therefore, a unit having a high layout property is desired. The present invention has been made in consideration of such a problem, and an object thereof is to improve the layout property of the unit. A unit according to an embodiment of the present invention includes: a rotating electrical machine; an inverter located in an outer periphery of the rotating electrical machine; a first gear connected downstream of the rotating electrical machine; a second gear to mesh with the first gear; a third gear connected downstream of the second gear via a shaft; and a fourth gear to mesh with the third gear. The shaft has a portion that overlaps a stator of the rotating electrical machine when viewed in a radial direction, and the inverter has a portion that overlaps the second gear when viewed in an axial direction. According to this embodiment, the second gear and the third gear are separated with respect to a shaft that passes through the outer periphery (outer peripheral space) of a main body of the rotating electrical machine. That is, the second gear and the third gear are separated by the shaft that extends to pass through the outer periphery of the main body of the rotating electrical machine. Accordingly, the interference between the second gear and a fourth gear or a component connected to the fourth gear (for example, a differential gear) can be avoided, and a dimension in the axial direction can be reduced, and further, the inverter is caused to overlap the second gear, that is, the inverter is disposed close to the shaft to overlap the second gear, which can contribute to reduce the unit in size. Therefore, a layout property of the unit can be improved. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic configuration diagram of a unit according to the present embodiment. FIG. 2 is a first diagram illustrating an arrangement of an inverter. FIG. 3 is a second diagram illustrating the arrangement of the inverter. DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of a unit 100 according to the present embodiment. A unit can also be referred to as, for example, a motor unit (a unit including at least a motor) or a power transmission device (a device including at least a power transmission mechanism). The motor is a rotating electrical machine having an electric motor function and/or a generator function (at least one of the electric motor function and the generator function). The power transmission mechanism is, for example, a gear mechanism and/or a differential gear mechanism. The device (unit) including the motor and the power transmission mechanism is included in concepts of both the motor unit and the power transmission device. The unit 100 includes a housing 10, a rotating electrical machine 20, a reduction mechanism 30, and a differential gear 40. The unit 100 is mounted on an electric vehicle, and the vehicle is an electric vehicle. The housing 10 includes a first cover 11, a second cover 12, a plate 13, and a case 14. The rotating electrical machine 20, the reduction mechanism 30, and the differential gear 40 are accommodated in the housing 10. The first cover 11 closes an opening of the cylindrical case 14 from one side in an axial direction (left side in FIG. 1), and the second cover 12 closes an opening of the case 14 from the other side in the axial direction via the plate 13. The rotating electrical machine 20 is provided in the case 14. The rotating electrical machine 20 is provided with one side in the axial direction as an output side. The rotating electrical machine 20 includes a rotor 21, a stator 22, and a rotation shaft 23, and constitutes a drive source of the vehicle. The rotor 21 is provided on an outer periphery of the rotation shaft 23. The stator 22 is provided in the case 14 and accommodates the rotor 21. The rotation shaft 23 protrudes from the rotor 21 toward both sides in the axial direction, and is supported by a bearing 51 provided on the first cover 11 and a bearing 52 provided on the plate 13. The rotation shaft 2