Rotating Electric Machine

Abstract

To provide a rotary electric machine having an improved supply structure of oil to a bearing.SOLUTION: A rotary electric machine relating to one embodiment of the invention comprises: a rotor having a shaft that extends along a central axis; a stator arranged on a radially outside of the rotor via an air gap; a bearing for pivotally supporting the shaft; and a bracket arranged on a radially outside of the bearing. The bracket has ribs extending in radial directions. The ribs have an oil channel for supplying an oil to the bearing.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a rotating electric machine. [Background technology]

[0002] Conventionally, there is known a rotating electric machine that supplies oil to a stator or bearing for cooling and lubrication. In the invention described in Patent Document 1, an oil passage is provided so that the oil that has cooled the stator reaches the bearing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-30284 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the invention described in Patent Document 1 has the problem that the need to provide an oil passage for allowing oil to reach the bearings makes the structure complicated and increases the cost.

[0005] In addition, when oil is sprayed onto the bearings from above, if there is a distance to the bearings, the oil tends to spread, resulting in poor cooling and lubrication efficiency.

[0006] An object of the present invention is to provide a rotating electrical machine having an improved structure for supplying oil to a bearing. [Means for solving the problem]

[0007] A rotating electric machine according to one aspect of the present invention includes a rotor having a shaft extending along a central axis, a stator arranged with an air gap between the rotor, a bearing supporting the shaft, and a bracket arranged radially outward of the bearing, the bracket having a rib extending radially, the rib having an oil passage for supplying oil to the bearing. The bracket has a protrusion that determines the axial depth of the oil passage at a position axially opposing the oil passage on the surface opposite to the surface having the oil passage.

[0008] In the rotating electric machine according to the above aspect, the oil passage extends from a vertically upper side of the bearing toward the bearing.

[0010] In the rotating electric machine of one aspect described above, the bracket has a plurality of radial ribs extending radially from the radial inside to the radial outside, and a plurality of circular ribs that include within a circle the position at which the bearing is positioned.

[0011] In the rotating electric machine according to the above aspect, the bracket suppresses vibrations by the rib having the oil passage, the plurality of radial ribs, and the plurality of circular ribs.

[0012] In one aspect of the rotating electric machine described above, the bracket is a one-side bracket arranged on one axial side of the rotor, and the one-side bracket also serves as an inverter case that houses an inverter that controls the rotation of the rotor. Effect of the Invention

[0013] According to one aspect of the present invention, it is possible to provide a rotating electrical machine having an improved structure for supplying oil to a bearing. [Brief description of the drawings]

[0014] [Figure 1] 1 is a perspective view of a motor unit according to a first embodiment of the present invention. [Diagram 2] 2 is a side cross-sectional view of the motor unit 10 of FIG. 1 taken along a plane perpendicular to the X-axis and passing through a central axis J. [Diagram 3]4 is a side view of the inverter case 200 as viewed from the other axial side. FIG. [Figure 4] FIG. 2 is a side view of the bracket 300 as viewed from one axial side. [Diagram 5] 11 is a side view of the bracket 300 as viewed from the other axial side. FIG. [Figure 6] 6 is a cross-sectional view taken along the line CC' of the bracket 300 in FIG. 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of a rotating electric machine according to the present invention will be described with reference to the drawings. In the drawings, the scale and number of components may be different from the actual structure in order to make each component easier to understand.

[0016] In addition, in the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional Cartesian coordinate system. In the XYZ coordinate system, the Y axis direction is parallel to the axis of the central axis J shown in Fig. 1. The Z axis direction is the vertical direction in Fig. 1 among the radial directions with respect to the central axis J. The X axis direction is perpendicular to both the Y axis direction and the Z axis direction. In each of the X axis direction, the side indicated by the arrow in the drawing is the + side, and the opposite side is the - side.

[0017] In the following description, the positive side (+Y side) in the Y-axis direction is referred to as "one side," and the negative side (-Y side) in the Y-axis direction is referred to as "the other side." Note that one side and the other side are names used merely for the purpose of description and do not limit the actual positional relationship and direction. Furthermore, unless otherwise specified, the direction parallel to the central axis J (Y-axis direction) is simply referred to as "axial direction," the radial direction centered on the central axis J is simply referred to as "radial direction," and the circumferential direction centered on the central axis J, i.e., around the axis of the central axis J, is simply referred to as "circumferential direction." The side approaching the central axis J in the radial direction is referred to as the "radial inner side," and the side moving away from the central axis J is referred to as the "radial outer side."

[0018] In this specification, "extending in the axial direction" includes not only extending strictly in the axial direction (Y-axis direction) but also extending in a direction tilted at an angle of less than 45° to the axial direction. In addition, in this specification, "extending in the radial direction" includes not only extending strictly in the radial direction, i.e., in a direction perpendicular to the axial direction (Y-axis direction), but also extending in a direction tilted at an angle of less than 45° to the radial direction. Furthermore, "parallel" includes not only being strictly parallel but also being tilted at an angle of less than 45° to each other. EXAMPLES

[0019] Fig. 1 is a perspective view of a motor unit according to a first embodiment of the present invention. The motor unit 10 in Fig. 1 is an example of a rotating electric machine. Fig. 2 is a side cross-sectional view showing the motor unit 10 in Fig. 1 cut along a plane perpendicular to the X-axis and passing through a central axis J.

[0020] The motor unit 10 is configured by accommodating a motor 150 (see FIG. 2) in a motor case 100. The motor case 100 is a cylindrical member and is open on one axial side and the other axial side. The opening on one axial side of the motor case 100 is closed by an inverter case 200, and the opening on the other axial side of the motor case 100 is closed by a bracket 300. The motor unit 10 can be used, for example, as a drive motor for an electric vehicle.

[0021] The motor 150 includes a rotor 170 having a shaft 400 extending along a central axis J, and a stator 160 disposed radially outside the rotor 170 via an air gap. The shaft 400 is supported by bearings 501 and 502 so as to be rotatable about the central axis J as a rotation axis. The motor case 100 accommodates the motor 150 by covering the stator 160 from the radial outside. The stator 160 has a coil end 161 on one axial side and a coil end 162 on the other axial side.

[0022] The inverter case 200 is a hollow, substantially cubic case that houses an inverter (not shown) that controls the rotation of the rotor 170. The inverter case 200 is disposed so that the other axial surface of the inverter case 200 is perpendicular to the axial direction.

[0023] The wall on the other axial side of the inverter case 200 serves as a bracket that closes the opening on the one axial side of the motor case 100. The inverter case 200 has a hole 220 (see FIG. 3) that penetrates in the axial direction in the wall on the other axial side. The hole 220 has a large diameter portion 221 on the other axial side that is larger in diameter than the diameter on the one axial side. The outer ring of the bearing 501 is fitted into the large diameter portion 221 of the hole 220 and fixed. That is, the wall on the other axial side of the inverter case 200 covers the bearing 501 from the radial outside. The shaft 400 is fixed to the inner ring of the bearing 501. The inverter case 200 has a rib 211 on the wall on the other axial side that extends from the surface on the other axial side to the other axial side. The rib 211 reinforces the strength of the wall on the other axial side of the inverter case 200. The inverter case 200 has a surface 210 that contacts the motor case 100 at the end on the other axial side.

[0024] Bracket 300 closes the opening on the other axial side of motor case 100. Bracket 300 is substantially disk-shaped, and is disposed so that the surface of the disk is perpendicular to the axial direction.

[0025] Bracket 300 has hole 320 (see FIG. 4) penetrating in the axial direction. Hole 320 has large diameter portion 321 on one axial side, the diameter of which is larger than the diameter of the other axial side. The outer ring of bearing 502 is fitted into large diameter portion 321 of hole 320 and fixed. Shaft 400 is fixed to the inner ring of bearing 502. Bracket 300 has rib 311 extending from a surface on one axial side to one axial side. Rib 311 reinforces the strength of bracket 300. Bracket 300 has surface 310 at one axial end that contacts motor case 100.

[0026] Motor case 100 has a hole 102 that penetrates a cylindrical wall surface in the axial direction. Motor case 100 also has a hole 101 that extends from hole 102 to the -X side and penetrates the cylindrical wall surface. Hole 101 is a hole for supplying oil from the outside into motor case 100. Oil that flows from hole 101 to hole 102 flows in the direction indicated by arrow A in the figure (one axial side) and in the direction indicated by arrow B (the other axial side).

[0027] The motor unit 10 is installed in an operating environment with the hole 102 of the motor case 100 positioned vertically above the arrangement of the bearings 501 and 501. The motor case 100 has a hole 104 that penetrates from the hole 102 to the vertically upward side of the coil end 161. Oil that flows from the hole 102 to the hole 104 reaches the coil end 161 due to its own weight and cools the coil end 161. The motor case 100 has a hole 103 that penetrates from the hole 102 to the vertically upward side of the coil end 162. Oil that flows from the hole 102 to the hole 103 reaches the coil end 162 due to its own weight and cools the coil end 162.

[0028] Inverter case 200 has hole 201 penetrating from hole 102 to the vertically upper side of bearing 501. Oil that flows from hole 102 into hole 201 falls under its own weight. Bracket 300 has hole 301 penetrating from hole 102 to the vertically upper side of bearing 502. Oil that flows from hole 102 into hole 301 falls under its own weight.

[0029] 3 is a side view of inverter case 200 as viewed from the other axial side. Surface 210 of inverter case 200 is the surface that contacts motor case 100. Surface 210 has opening 201a that is an oil inlet opening where hole 201 opens toward hole 102 of motor case 100.

[0030] The inverter case 200 has ribs 251 and 252 protruding from the surface 250 on the other axial side. The ribs 251 are a plurality of circular ribs that include the large diameter portion 221, which is the position of the bearing, within a circle. The ribs 252 are a plurality of radial ribs that extend radially from the radial inside to the radial outside. The strength of the inverter case 200 is reinforced by the ribs 211, 212, 251, and 252, suppressing vibration. The ribs 211, 212, 251, and 252 of the inverter case 200 that serve as brackets have a structure in which a plurality of radial and circular ribs intersect from the center, and the weight is significantly reduced by reducing the thickness of the inverter case 200, while the rib structure ensures rigidity and suppresses vibration.

[0031] The ribs 211 and 212 are an example of the rib 252 which is a radial rib. The ribs 211 and 212 have an oil passage 213 therebetween. The oil passage 213 is recessed toward one axial side from the ribs 211 and 212. An upper opening of the oil passage 213 in the vertical direction is connected to the hole 201. The oil passage 213 extends vertically downward from the hole 201 and reaches the large diameter portion 221. A lower opening of the oil passage 213 in the vertical direction is connected to the large diameter portion 221. According to the present embodiment, the ribs 211 and 212 which reinforce the inverter case 200 have the oil passage 213, so that the structure is not complicated and an increase in costs can be prevented.

[0032] The large diameter portion 221 of the inverter case 200 is formed by recessing a radially inner portion of the surface 253 located on the other axial side of the surface 250 toward one axial side. The bearing 501 is fixed to the large diameter portion 221. The oil passage 213 supplies oil to the bearing 501. If the oil passage 213 does not exist, the oil flowing out from the hole 201 will scatter, and there is a risk that an amount of oil sufficient for lubricating the bearing 501 will not reach the bearing 501. According to this embodiment, the oil flowing out from the hole 201 flows down along the oil passage 213, so that an amount of oil sufficient for lubricating the bearing 501 reaches the bearing 501. According to this embodiment, since the distance from the oil passage 213 to the bearing 501 is short, the oil does not diffuse, and the efficiency of cooling and lubrication can be improved.

[0033] 4 is a side view of bracket 300 as viewed from one axial side. Surface 310 of bracket 300 is the surface that contacts motor case 100. Surface 310 has opening 301a that is an oil inlet opening of hole 301 that opens toward hole 102 of motor case 100.

[0034] The bracket 300 has ribs 351 and 352 protruding from the surface 350 on one side in the axial direction. The ribs 351 are a plurality of circular ribs that include the large diameter portion 321, which is the position where the bearing is arranged, within a circle. The ribs 352 are a plurality of radial ribs that extend radially from the inside in the radial direction to the outside in the radial direction. The strength of the bracket 300 is reinforced by the ribs 311, 312, 351, and 352, and vibration is suppressed. The ribs 311, 312, 351, and 352 of the bracket 300 have a structure in which a plurality of radial and circular ribs intersect from the center, and the weight is significantly reduced by reducing the thickness of the bracket 300, while the rib structure ensures rigidity and suppresses vibration.

[0035] The ribs 311 and 312 are an example of the rib 352 which is a radial rib. The ribs 311 and 312 have an oil passage 313 therebetween. The oil passage 313 is recessed toward one axial side from the ribs 311 and 312. An upper opening of the oil passage 313 in the vertical direction is connected to the hole 301. The oil passage 313 extends vertically downward from the hole 301 and reaches the large diameter portion 321. A lower opening of the oil passage 313 in the vertical direction is connected to the large diameter portion 321. According to this embodiment, the ribs 311 and 312 which reinforce the bracket 300 have the oil passage 313, so that the structure is not complicated and an increase in costs can be prevented.

[0036] The large diameter portion 321 of the bracket 300 is formed by recessing a radially inner portion of the surface 353 located on one axial side of the surface 350 toward the other axial side. The bearing 502 is fixed to the large diameter portion 321. The oil passage 313 supplies oil to the bearing 502. If the oil passage 313 is not provided, the oil flowing out from the hole 301 will scatter, and there is a risk that an amount of oil sufficient for lubricating the bearing 502 will not reach the bearing 501. According to this embodiment, the oil flowing out from the hole 301 flows down along the oil passage 313, so that an amount of oil sufficient for lubricating the bearing 502 reaches the bearing 502. According to this embodiment, the distance from the oil passage 313 to the bearing 502 is short, so that the oil does not diffuse, and the efficiency of cooling and lubrication can be improved.

[0037] Fig. 5 is a side view of bracket 300 as viewed from the other axial side. Fig. 6 is a CC' cross-sectional view of bracket 300 in Fig. 5. Bracket 300 has ribs 317 on surface 315, which is the surface on the other axial side, protruding from surface 315 to the other axial side. Ribs 317 are a plurality of radial ribs extending radially from the radial inside to the radial outside.

[0038] Bracket 300 also has protrusion 316 that protrudes from surface 315 to the other axial side at a position on the surface on the other axial side that faces oil passage 313 provided on one axial side in the axial direction. That is, bracket 300 has protrusion 316 on the surface opposite to the surface having oil passage 313. Providing protrusion 316 makes it possible to determine the axial depth of oil passage 313 in accordance with the axial position of bearing 502. Protrusion 316 also has the effect of reinforcing the strength of bracket 300.

[0039] The present invention is not limited to the above-mentioned embodiment, and various improvements and design changes may be made without departing from the spirit of the present invention. In addition, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0040] 10...motor unit 10...motor case, 200...inverter case, 300...bracket

Claims

1. a rotor having a shaft extending along a central axis; a stator disposed across a gap from the rotor; A bearing that supports the shaft; A bracket disposed radially outward of the bearing; Equipped with The bracket has a radially extending rib, the rib has an oil passage for supplying oil to the bearing, The bracket has a protrusion that determines the axial depth of the oil passage at a position axially opposite to the oil passage on a surface opposite to a surface having the oil passage. Rotating electric motor.

2. The oil passage extends from a vertically upper side of the bearing toward the bearing. The rotating electric machine according to claim 1 .

3. The bracket has a plurality of radial ribs extending radially from the radial inside to the radial outside, and a plurality of circular ribs including within a circle the arrangement position of the bearing.

3. A rotating electric machine according to claim 1 or 2.

4. The bracket suppresses vibrations by a rib having the oil passage, the plurality of radial ribs, and the plurality of circular ribs. The rotating electric machine according to claim 3 .

5. the bracket is a one-side bracket disposed on one axial side of the rotor, and the one-side bracket also serves as an inverter case that houses an inverter that controls rotation of the rotor. The rotating electric machine according to claim 1 .

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