Motor housing

Abstract

The invention provides a motor housing capable of promoting heat transfer from a motor to the motor housing. The motor housing includes: a housing inner wall; and an oil passage which is provided on the inner wall of the housing and through which lubricating oil flows, the inner wall of the housing being provided with: a plurality of wedge sections which are arranged side by side in the circumferential direction of the stator and which support the outer circumference of the stator; and a wave-shaped portion disposed on the outside in the radial direction of the stator with respect to the plurality of wedge-shaped portions and disposed around the plurality of wedge-shaped portions, the oil passage being provided between the plurality of wedge-shaped portions and the wave-shaped portion and extending in a curved manner such that the lubricating oil flows in the radial direction and the circumferential direction of the stator.

Description

Technical Field

[0001] The present disclosure relates to a motor housing. Background Art

[0002] Patent Document 1 discloses a structure in which a gap is formed between the inner peripheral surface of a motor case and the outer peripheral surface of a stator core, and a motor is cooled by allowing lubricating oil to flow through the gap.

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-122451 Summary of the invention

[0006] [Problems to be Solved by the Invention]

[0007] In the structure disclosed in Patent Document 1, the gap portion that becomes the oil path is thin and narrow, so the flow rate of the lubricating oil is limited. In addition, in the structure disclosed in Patent Document 1, the flow path of the lubricating oil in the oil path becomes a laminar flow with little disturbance, so the heat transfer from the motor to the motor housing is limited, and there is room for improvement.

[0008] The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a motor case that can promote heat transfer from a motor to the motor case.

[0009] [Methods for solving the problem]

[0010] The motor housing disclosed in the present invention comprises: a housing inner wall; and an oil passage, which is arranged on the housing inner wall and through which lubricating oil flows. The housing inner wall comprises: a plurality of wedge-shaped portions, which are arranged in a circumferential direction of a stator and support the outer periphery of the stator; and a corrugated portion, which is arranged radially outward of the stator relative to the plurality of wedge-shaped portions and is arranged around the plurality of wedge-shaped portions. The oil passage is arranged between the plurality of wedge-shaped portions and the corrugated portion and extends in a curved manner so as to allow the lubricating oil to flow in the radial and circumferential directions of the stator.

[0011] [Effects of the invention]

[0012] According to the present disclosure, the flow of lubricating oil is disturbed and stirred in the oil passage due to the curved extension of the oil passage, so that heat transfer from the motor to the motor case can be promoted. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a cross-sectional view showing the structure of the motor case according to the embodiment.

[0014] Figure 2It is a cross-sectional view showing the structure of a modified example of the motor case according to the embodiment. DETAILED DESCRIPTION

[0015] The motor housing according to the embodiment of the present disclosure will be described with reference to the drawings. It should be noted that the components in the following embodiment include components that can be easily replaced by those skilled in the art, or components that are substantially the same.

[0016] The motor housing of the embodiment is used to accommodate a motor composed of a stator and a rotor. The motor housing of the embodiment is formed of, for example, aluminum die casting. In addition, as described later, the motor housing of the embodiment contains lubricating oil that is in direct contact with the motor (stator).

[0017] like Figure 1 As shown, the motor case 1 includes a case inner wall 11 and an oil passage 12. In this figure, for convenience of explanation, a part of a cross section obtained by cutting the cylindrical motor case 1 and the cylindrical stator 2 at a predetermined position in the axial direction is selected and shown.

[0018] The housing inner wall 11 includes a plurality of wedge-shaped portions 111 and a corrugated portion 112. The plurality of wedge-shaped portions 111 and the corrugated portion 112 are integrally formed. Figure 1 As shown, the plurality of wedge-shaped portions 111 and the wave-shaped portions 112 are separately provided at predetermined positions in the axial direction of the stator 2, but are connected at positions at both ends (or one end) in the axial direction of the stator 2. However, the plurality of wedge-shaped portions 111 and the wave-shaped portions 112 may also be separately formed.

[0019] The plurality of wedge-shaped portions 111 are arranged on the outer periphery of the cylindrical stator 2. That is, the plurality of wedge-shaped portions 111 are arranged in a row in the circumferential direction of the stator 2. In addition, the plurality of wedge-shaped portions 111 are arranged at predetermined intervals in the circumferential direction of the stator 2. In addition, the front ends of the plurality of wedge-shaped portions 111 abut against the outer periphery of the stator 2 to support the outer periphery of the stator 2. In addition, although Figure 1 Although not shown in the figure, the stator 2 is also fixed by fastening members (bolts, etc.) not shown in the figure.

[0020] The corrugated portion 112 is arranged radially outside the stator 2 with respect to the plurality of wedge-shaped portions 111. In addition, the corrugated portion 112 is arranged around the stator 2 and the plurality of wedge-shaped portions 111.

[0021] The oil passage 12 is a flow passage for flowing lubricating oil. The oil passage 12 is provided in its entirety along the circumferential direction of the stator 2. That is, the lubricating oil in the oil passage 12 flows in its entirety along the circumferential direction of the stator 2.

[0022] In addition, the oil passage 12 is provided between the plurality of wedge-shaped portions 111 and the corrugated portion 112. That is, the oil passage 12 is formed by passing through the surfaces of the plurality of wedge-shaped portions 111 and the outer peripheral surface of the stator 2 between the wedge-shaped portions 111 (see Figure 1A portion), and the space divided by the surface of the corrugated portion 112.

[0023] In addition, if Figure 1 As shown in the B part of the figure, the oil passage 12 is curved and extended in such a manner that the lubricating oil flows in the radial direction and the circumferential direction of the stator 2. That is, when the oil passage 12 is cut at a predetermined position in the axial direction of the stator 2 as shown in the figure, the space extending in the radial direction (radially outside and radially inside) and the space extending in the circumferential direction are alternately connected. In other words, the oil passage 12 is formed in a maze shape (waveform) or a sawtooth shape. As a result, the lubricating oil in the oil passage 12 flows alternately in the radial direction and the circumferential direction as shown in the B part of the figure.

[0024] Here, in a general motor housing, for example, the outer periphery of the stator is supported by the cylindrical inner wall of the housing, and the inner wall of the housing is in close contact with the outer periphery of the stator. On the other hand, in the motor housing of the embodiment, the stator 2 is supported by the front ends of the plurality of wedge-shaped portions 111, such as Figure 1 As shown in the A portion of FIG. 1 , the lubricating oil directly contacts the stator 2 between the wedge-shaped portions 111 , and the area (liquid contact area) of direct contact between the stator 2 and the lubricating oil increases. This promotes heat transfer from the stator 2 to the motor housing 1 .

[0025] Furthermore, in the motor case of the embodiment, since the stator 2 is supported by the front ends of the plurality of wedge-shaped portions 111 , there is no need to separately provide a stator bracket or the like.

[0026] In addition, since the oil passage of a general motor housing is an oil passage in which lubricating oil flows only in the circumferential direction, for example, heat transfer from the stator to the motor housing is limited. On the other hand, in the motor housing of the embodiment, lubricating oil flows alternately in the radial direction and the circumferential direction in the oil passage 12, colliding with the side surface of the wedge-shaped portion 111, the outer periphery of the stator 2, and the surface of the corrugated portion 112. Thus, heat transfer from the stator 2 to the motor housing 1 is promoted.

[0027] In the motor case of the embodiment, the large surface area of ​​the corrugated portion 112 promotes heat transfer between the lubricant and the case inner wall 11 , thereby promoting heat transfer from the stator 2 to the case inner wall 11 and air cooling via the motor case 1 .

[0028] (Variation)

[0029] Reference Figure 2 A modified example of the motor housing of the embodiment of the present disclosure is described. The motor housing 1A involved in this modified example includes a housing inner wall 11, an oil passage 12, and a plurality of air-cooling fins 13. The structures of the housing inner wall 11 and the oil passage 12 are similar to those of the motor housing 1 described above (see Figure 1 ) are the same, so the description is omitted.

[0030] The plurality of air-cooling fins 13 are provided on the outer periphery of the motor case 1A. That is, the plurality of air-cooling fins 13 are arranged in a row in the circumferential direction of the stator 2. In addition, the plurality of air-cooling fins 13 are provided in the circumferential direction of the stator 2 at predetermined intervals.

[0031] Thus, by providing the motor case 1A with the plurality of air-cooling fins 13 , air cooling through the motor case 1A is further promoted.

[0032] According to the motor case of the above-described embodiment, the oil passage 12 extends in a curved manner, and the flow of lubricating oil is disturbed and stirred in the oil passage 12 , thereby promoting heat transfer from the motor (stator 2 ) to the motor case 1 .

[0033] In the motor housing of the embodiment, the oil passage 12 formed by a wide gap is provided between the wedge-shaped portion 111 and the corrugated portion 112, so that the lubricating oil flows at a large flow rate and at a high speed. As a result, the strong high-speed flow is disturbed with the outer periphery of the stator 2 (see FIG. 1 ) which constitutes a part of the oil passage 12. Figure 1 A part) directly collides with the stator 2 to promote heat transfer from the stator 2 to the motor housing 1.

[0034] In addition, in the motor housing of the embodiment, the lubricating oil that has received the heat of the motor (stator 2) and has become high temperature is sent to the outside of the motor housing 1 and cooled by, for example, an external oil cooler (water cooling or air cooling). As a result, a water jacket around the motor housing 1 is not required, so the structure can be simplified, miniaturization and cost reduction can be achieved.

[0035] Those skilled in the art can easily derive further effects and variations. Therefore, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Therefore, various changes can be made without departing from the spirit or scope of the general inventive concept defined by the attached claims and their equivalents.

[0036] [Explanation of Reference Numerals]

[0037] 1. 1A motor housing

[0038] 11 Inner wall of shell

[0039] 111 Wedge

[0040] 112 Waveform

[0041] 12 Oil circuit

[0042] 13 Air Cooling Fins

[0043] 2 Stator

Claims

1. A motor housing, comprising: the inner wall of the housing; and The oil passage is arranged on the inner wall of the housing for the lubricating oil to flow. The inner wall of the housing has: A plurality of wedge-shaped portions are arranged in a circumferential direction of the stator to support the outer circumference of the stator; and The corrugated portion is arranged radially outward of the stator relative to the plurality of wedge-shaped portions and is arranged around the plurality of wedge-shaped portions. The oil passage is provided between the plurality of wedge-shaped portions and the corrugated portion, and extends in a curved manner so as to allow the lubricating oil to flow in radial and circumferential directions of the stator.

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