阅读说明：本技术 旋转电机 (Rotating electrical machine ) 是由 田中修平 于 2021-04-29 设计创作，主要内容包括：提供不产生NV而能够抑制轴承的烧伤的旋转电机。旋转电机具备：旋转轴,其以沿着水平方向的轴线为中心进行旋转；轴承,其将旋转轴支承为能够旋转并且能够供从位于轴线的轴向的一方的上游部供给的冷却介质朝向位于轴向的另一方的下游部流通；保持部,其保持轴承；空间部,其设置于比保持部的外周部靠外侧的位置,且与下游部连续并且能够供冷却介质流通；冷却介质承接部,其设置于比轴承的下游部靠轴向的另一方的位置,限制在轴承流通后的冷却介质从空间部的流出量；冷却介质引导部,其设置于空间部,在轴向上从冷却介质承接部朝向轴承的上游部引导冷却介质；冷却介质供给部,其将由冷却介质引导部进行了引导的冷却介质向轴承的上游部供给。(Provided is a rotating electric machine which can suppress bearing seizure without causing NV. The rotating electric machine is provided with: a rotating shaft that rotates around an axis line along a horizontal direction; a bearing that rotatably supports the rotary shaft and allows the cooling medium supplied from one upstream portion in the axial direction of the axis to flow toward the other downstream portion in the axial direction; a holding portion that holds a bearing; a space section provided outside the outer peripheral section of the holding section, continuous with the downstream section, and through which a cooling medium can flow; a cooling medium receiving portion provided at the other axial side of the downstream portion of the bearing, for limiting the outflow amount of the cooling medium from the space portion after flowing through the bearing; a cooling medium guide portion provided in the space portion and guiding the cooling medium from the cooling medium receiving portion toward an upstream portion of the bearing in the axial direction; and a cooling medium supply unit that supplies the cooling medium guided by the cooling medium guide unit to an upstream portion of the bearing.)

1. A rotating electric machine, wherein,

the rotating electric machine includes:

a rotating shaft that rotates around an axis line along a horizontal direction;

a bearing that is attached to an outer peripheral portion of the rotary shaft, rotatably supports the rotary shaft, and allows a cooling medium supplied from one upstream portion in an axial direction of the axis to flow toward the other downstream portion in the axial direction;

a holding portion that holds the bearing;

a space portion provided at a position outside an outer peripheral portion of the holding portion in a radial direction of the rotary shaft, continuous with the downstream portion, and through which the cooling medium can flow;

a cooling medium receiving portion provided at the other side in the axial direction than the downstream portion of the bearing, for limiting an outflow amount of the cooling medium flowing through the bearing from the space portion;

a cooling medium guide portion provided in the space portion and configured to guide the cooling medium from the cooling medium receiving portion toward the upstream portion of the bearing in the axial direction; and

and a cooling medium supply unit configured to supply the cooling medium guided by the cooling medium guide unit to the upstream portion of the bearing.

2. The rotating electric machine according to claim 1,

an outer peripheral surface of the holding portion is a cooling medium guide surface that guides the cooling medium toward the upstream portion of the bearing by a centrifugal force when the rotary shaft rotates.

3. The rotary electric machine according to claim 1 or 2,

the space portion is formed so that the cooling medium can flow from the cooling medium receiving portion toward the upstream portion of the bearing, and is formed in a ring shape centered on the axis when viewed in the axial direction.

4. The rotary electric machine according to claim 1 or 2,

the space portion is provided with a guide portion that is inclined from the downstream portion side to the upstream portion side of the bearing in the axial direction as going from an upstream side to a downstream side in a rotational direction of the rotary shaft,

the induction portion is one of a convex portion protruding toward the inside in the radial direction and a concave portion recessed toward the outside in the radial direction.

5. The rotary electric machine according to claim 1 or 2,

the cooling medium guide portion is provided above the holding portion so as to intersect with the circumferential direction of the rotating shaft.

6. The rotary electric machine according to claim 1 or 2,

the rotating electric machine includes:

a rotor core attached to an outer peripheral portion of the rotating shaft;

a stator having a stator core disposed with a gap from an outer peripheral portion of the rotor core and a conductive member attached to the stator core; and

a covering member that covers a lap portion of the conductive member that protrudes outward in the axial direction from the stator core and is formed in a ring shape centered on the axis when viewed in the axial direction,

the space portion is provided between an inner peripheral surface of the cover member and an outer peripheral surface of the holding portion.

7. The rotating electric machine according to claim 6,

the cooling medium receiving portion protrudes from the inner peripheral surface of the cover member toward the inside in the radial direction.

8. The rotating electric machine according to claim 6,

the inner peripheral surface of the cover member is inclined such that an inner diameter thereof becomes larger as it goes from the downstream portion side to the upstream portion side of the bearing in the axial direction.

Technical Field

The present invention relates to a rotating electric machine.

Background

Conventionally, a structure of a rotating electric machine or the like in which a rotor is supported by a rolling bearing is known. In the rotating electrical machine and the like described above, various techniques have been proposed for supplying an appropriate amount of cooling medium to the bearing in order to prevent seizure of the bearing.

For example, patent document 1 (japanese patent application laid-open No. 2019 and 218947) discloses a structure of a vacuum pump including: a bearing supporting a rotating shaft of the rotor; a storage unit that stores a cooling medium supplied to the bearing; a micro flow pump which discharges the cooling medium in a droplet form to a circulation path on the rotating shaft side among circulation paths between the bearing and the storage part; and a flow path having a capillary structure for moving the cooling medium in the storage unit to the micro flow pump by capillary force. According to the technique described in patent document 1, the coolant that has moved from the storage section to the micro flow pump through the flow path of the capillary structure is discharged in the form of droplets from the micro flow pump to the member on the rotation axis side. The cooling medium is transferred to the surface of the member on the rotating shaft side and moves to the bearing. This makes it possible to stably supply the cooling medium to the bearing.

Disclosure of Invention

Problems to be solved by the invention

However, in the technique described in patent document 1, the cooling medium is supplied to the bearing by using the surface tension, and therefore the amount of the cooling medium that can be supplied to the bearing is limited. Therefore, if the cooling medium is insufficient, the cooling medium is concentrated on the outer peripheral portion of the bearing by centrifugal force, and there is a possibility that the cooling medium is not distributed on the inner peripheral portion of the bearing, thereby causing seizure of the bearing.

Further, a structure of a horizontally-placed rotary electric machine in which a rotary shaft of the rotary electric machine is arranged along a horizontal direction is known. In such a horizontally-placed rotating electrical machine, it is considered to increase the amount of cooling medium in order to prevent burning of the bearing. However, when the cooling medium is added, although the cooling medium is distributed in the inner peripheral portion of the bearing, a part of the cooling medium may enter an air gap between the rotor and the stator located downstream of the bearing in the cooling medium flow path, and nv (noise vibration) may occur.

Accordingly, an object of the present invention is to provide a rotating electric machine capable of suppressing seizure of a bearing without generating NV.

Means for solving the problems

The rotating electric machine of the present invention has the following configuration.

(1) A rotating electric machine according to an aspect of the present invention includes: a rotating shaft that rotates around an axis line along a horizontal direction; a bearing that is attached to an outer peripheral portion of the rotary shaft, rotatably supports the rotary shaft, and allows a cooling medium supplied from one upstream portion in an axial direction of the axis to flow toward the other downstream portion in the axial direction; a holding portion that holds the bearing; a space portion provided at a position outside an outer peripheral portion of the holding portion in a radial direction of the rotary shaft, continuous with the downstream portion, and through which the cooling medium can flow; a cooling medium receiving portion provided at the other side in the axial direction than the downstream portion of the bearing, for limiting an outflow amount of the cooling medium flowing through the bearing from the space portion; a cooling medium guide portion provided in the space portion and configured to guide the cooling medium from the cooling medium receiving portion toward the upstream portion of the bearing in the axial direction; and a cooling medium supply unit that supplies the cooling medium guided by the cooling medium guide unit to the upstream portion of the bearing.

(2) In the rotating electrical machine according to the aspect (1), the outer peripheral surface of the holding portion may be a cooling medium guide surface that guides the cooling medium toward the upstream portion of the bearing by a centrifugal force when the rotating shaft rotates.

(3) In the rotating electrical machine according to the aspect (1) or (2), the space portion may be formed in a ring shape centered on the axis when viewed in the axial direction, so that the cooling medium can flow from the cooling medium receiving portion toward the upstream portion of the bearing.

(4) In the rotating electrical machine according to any one of the above (1) to (3), the space portion may be provided with a guide portion that is inclined from the downstream portion side to the upstream portion side of the bearing in the axial direction as going from an upstream side to a downstream side in a rotation direction of the rotating shaft, and the guide portion may be one of a convex portion that protrudes inward in the radial direction and a concave portion that is concave outward in the radial direction.

(5) In the rotating electrical machine according to any one of the above aspects (1) to (4), the cooling medium guide portion may be provided so as to intersect with a circumferential direction of the rotating shaft at a position above the holding portion.

(6) In the rotating electrical machine according to any one of the aspects (1) to (5), the rotating electrical machine may include: a rotor core attached to an outer peripheral portion of the rotating shaft; a stator having a stator core disposed with a gap from an outer peripheral portion of the rotor core and a conductive member attached to the stator core; and a covering member that covers a bridge portion of the conductive member that protrudes outward in the axial direction from the stator core, and that is formed in a ring shape centered on the axis when viewed in the axial direction, the covering member having the space portion provided between an inner peripheral surface of the covering member and an outer peripheral surface of the holding portion.

(7) In the rotating electrical machine according to the aspect (6), the cooling medium receiver may protrude from the inner circumferential surface of the cover member toward the inside in the radial direction.

(8) In the rotating electrical machine according to the aspect (6) or (7), the inner peripheral surface of the cover member may be inclined such that an inner diameter thereof increases from the downstream portion side toward the upstream portion side of the bearing in the axial direction.

Effects of the invention

According to the aspect (1), in the horizontally arranged rotating electrical machine, the space portion that is continuous with the downstream portion of the bearing and through which the cooling medium can flow is formed in the outer peripheral portion of the holding portion that holds the bearing. The space portion is provided with a cooling medium guide portion that guides the cooling medium from the cooling medium receiving portion toward the upstream portion of the bearing. Thus, the cooling medium that flows through the bearing and is discharged from the bearing toward the downstream portion circulates through the space portion by the cooling medium guide portion, passes through the cooling medium supply portion, and is supplied again to the upstream portion of the bearing. By reusing a part of the cooling medium in this manner, the amount of the cooling medium supplied to the bearing can be ensured much more constantly. Therefore, the cooling medium can be stably supplied, and seizure of the bearing can be suppressed.

The cooling medium receiving portion is provided at the other axial position than the downstream portion of the bearing, and limits the amount of the cooling medium flowing through the bearing to flow out from the space portion to the outside. This can suppress the cooling medium discharged from the downstream portion of the bearing from entering the air gap between the rotor and the stator. Therefore, the amount of the cooling medium supplied to the bearing can be increased while suppressing the generation of NV due to the cooling medium entering the air gap.

Therefore, the rotating electric machine in which seizure of the bearing can be suppressed without causing NV can be provided.

According to the aspect of (2), the outer peripheral surface of the holding portion is the cooling medium guide surface that guides the cooling medium toward the upstream portion of the bearing by a centrifugal force, and the cooling medium that is transferred to the upstream portion of the bearing by the cooling medium guide surface flows from the upstream portion toward the downstream portion in the bearing, thereby cooling and lubricating the bearing. This makes it possible to supply a large amount of cooling medium to the bearing at all times, and thus to suppress seizure of the bearing. Since the outer peripheral surface of the holding portion that holds the bearing can be used as the cooling medium guide surface, it is not necessary to add a new member for guiding the cooling medium to the upstream portion of the bearing. Therefore, the cooling medium can be efficiently supplied to the bearing by centrifugal force while suppressing an increase in the number of components.

According to the aspect (3), the space portion is formed in a ring shape with the axis as the center, and the cooling medium can flow through the space portion. Thus, the cooling medium moves in the annular circumferential direction in the space portion by the centrifugal force obtained when the bearing flows. The cooling medium moving in the circumferential direction reaches the cooling medium supply portion and is then supplied to the upstream portion of the bearing. Thereby, the cooling medium cools and lubricates the bearing. Therefore, the cooling medium can be stably supplied from the cooling medium receiving portion to the upstream portion of the bearing by effectively utilizing the centrifugal force of the cooling medium, and the seizure of the bearing can be effectively suppressed.

According to the aspect (4), the guide portion provided in the space portion is inclined from the downstream portion side to the upstream portion side of the bearing in the axial direction as going from the upstream side to the downstream side in the rotation direction of the rotary shaft. Therefore, when the cooling medium discharged from the bearing moves in the circumferential direction in the rotation direction of the rotating shaft in the space portion by the centrifugal force, the cooling medium moves from the downstream side to the upstream side of the bearing in the axial direction along the guide portion. Therefore, the cooling medium can be more efficiently supplied to the upstream portion of the bearing. The induction part is a convex part or a concave part. Thus, the induction portion can be provided with a simple structure, and the cooling medium can be efficiently supplied to the bearing.

According to the aspect (5), the cooling medium guide portion is provided above the holding portion. The centrifugal force of the cooling medium is minimized at the upper portion of the holding portion. The cooling medium guide portion is provided so as to intersect with the circumferential direction. Therefore, the cooling medium that moves in the circumferential direction in the space portion due to the centrifugal force reaches the cooling medium guide portion in a state where the momentum is weakened at the upper portion of the holding portion. The cooling medium that has reached the cooling medium guide portion is guided to the upstream portion of the bearing while being restricted from moving in the circumferential direction by the cooling medium guide portion. As a result, compared to the case where the coolant reaches the coolant guide portion in a state where the coolant is very strong, scattering of the coolant can be suppressed, and the coolant can be more efficiently supplied to the upstream portion of the bearing.

According to the aspect (6), the annular covering member is provided to cover the lap portion of the conductive member. Thereby, the periphery of the lap portion is covered with the covering member. Therefore, for example, by supplying the cooling medium between the covering member and the lap portion, the cooling medium can be supplied to the entire lap portion, and the lap portion can be cooled efficiently.

A space is provided between the inner peripheral surface of the cover member and the outer peripheral surface of the holding portion. This allows the space to be formed without adding a new member. Therefore, the cooling medium can be stably supplied to the bearing while suppressing an increase in the number of components.

According to the aspect (7), the cooling medium receiving portion protrudes radially inward from the inner peripheral surface of the cover member. In this way, since the covering member is formed integrally with the cooling medium receiver, it is not necessary to add a new member for providing the cooling medium receiver. Therefore, the cooling medium can be stably supplied to the bearing while suppressing an increase in the number of components.

According to the aspect of (8), the inner peripheral surface of the cover member is inclined such that the inner diameter increases as going from the downstream side toward the upstream side of the bearing in the axial direction. Thereby, the cooling medium discharged from the bearing is transferred to the inner circumferential surface of the cover member by the centrifugal force and moves in the circumferential direction, and moves from the downstream portion side to the upstream portion side of the bearing in the axial direction along the inclined inner circumferential surface. Therefore, the cooling medium can be more efficiently supplied to the upstream portion of the bearing.

Drawings

Fig. 1 is a sectional view of a rotating electric machine according to a first embodiment.

Fig. 2 is a sectional view of the cover member of the first embodiment.

Fig. 3 is a sectional view of a cover member of the second embodiment.

Fig. 4 is a sectional view of a cover member of the third embodiment.

Fig. 5 is a sectional view of a cover member of the fourth embodiment.

Fig. 6 is a sectional view of a cover member of the fifth embodiment.

Description of reference numerals:

1 rotating electrical machine

4 stator

5. 205, 305, 405, 505 cover member

14 coolant receiving part

16 guide for cooling medium

17. 517 cooling medium supply unit

23 holding part

31 rotating shaft

32 rotor core

37 upstream part

38 downstream portion

41 stator core

42 conductive member

46 lap joint part

50 space part

51. 251 cooling medium induction surface

352. 452 inducer part

The C axis.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

(first embodiment)

(rotating electric machine)

Fig. 1 is a sectional view of a rotating electric machine 1 according to a first embodiment.

The rotating electric machine 1 is a traveling motor mounted on a vehicle such as a hybrid vehicle or an electric vehicle. However, the configuration of the present invention is not limited to the motor for running, and may be used as a motor for power generation, a motor for other applications, and a rotating electrical machine 1 (including a generator) other than a vehicle. The rotating shaft 31 of the rotating electric machine 1 of the present embodiment is disposed substantially parallel to the horizontal direction. In the following description, a direction along the axis C of the rotary shaft 31 in the rotary electric machine 1 is sometimes referred to as an axial direction, a direction perpendicular to the axis C is sometimes referred to as a radial direction, and a direction about the axis C is sometimes referred to as a circumferential direction. The axis C of the rotary shaft 31 is arranged along the horizontal direction.

The rotating electric machine 1 includes a housing 2, a rotor 3, a stator 4, and a cover member 5.

(outer cover)

The housing 2 includes a housing main body 21 and a side cover 22.

The housing main body 21 is formed in a box shape that opens in one axial direction. The housing main body 21 accommodates the rotor 3, the stator 4, and the cover member 5.

The side cover 22 covers the opening of the housing main body 21. The side cover 22 is fixed to the case main body 21 using a fastening member such as a bolt. A part of the side cover 22 protrudes in the axial direction toward the inside of the housing 2. The protruding portion serves as a holding portion 23 for holding a bearing 33 described later. The holding portion 23 is formed in an annular shape centered on the axis C when viewed in the axial direction.

The cooling medium is accommodated in the housing 2 formed in this manner. The rotor 3 and the stator 4 are disposed in the casing 2 in a state in which a part thereof is immersed in the cooling medium. As the cooling medium, atf (automatic Transmission fluid) or the like, which is a working oil used for lubrication of a Transmission, power Transmission, or the like, is preferably used.

(rotor)

The rotor 3 is configured to be rotatable about an axis C. The rotor 3 includes a rotating shaft 31 and a rotor core 32.

The rotary shaft 31 is formed in a cylindrical shape centered on the axis C. The rotary shaft 31 is configured to be rotatable with respect to the housing 2.

The rotor core 32 is provided on the outer periphery of the rotating shaft 31. The rotor core 32 is formed in a ring shape. The rotor core 32 is configured to be rotatable around the axis C integrally with the rotary shaft 31. A permanent magnet, not shown, is disposed on the outer periphery of the rotor core 32. The permanent magnet is, for example, a rare-earth magnet. Examples of the rare-earth magnet include neodymium magnet, samarium-cobalt magnet, and praseodymium magnet. The permanent magnets extend in the axial direction inside the rotor core 32, for example. The permanent magnets are formed in plurality at intervals in the circumferential direction. The permanent magnets may be disposed on the outer peripheral surface of the rotor core 32, for example.

The rotor formed in this way is supported rotatably with respect to the housing 2 by a bearing 33 attached to the outer periphery of the rotating shaft 31. The bearing 33 is a rolling bearing 33 having an inner ring 34, an outer ring 35, and rolling elements 36. The bearings 33 are provided in a pair on the outer side in the axial direction than both end portions in the axial direction of the rotor core 32. The pair of bearings 33 has the same structure. Therefore, in the following description, the bearing 33 provided on the side cover 22 side in the axial direction with respect to the rotor core 32 will be described in detail, and the description of the bearing 33 provided on the side opposite to the side cover 22 in the axial direction will be omitted.

The inner race 34 of the bearing 33 is inserted and fixed into the outer peripheral portion of the rotary shaft 31. The outer ring 35 of the bearing 33 is fixed to the inner peripheral portion of the holding portion 23 formed in the side cover 22 of the housing 2 (see also fig. 2). Therefore, the rotary shaft 31 is rotatably supported with respect to the housing 2 via the bearing 33. Inside the bearing 33, the cooling medium can flow from an upstream portion 37 located on the outer side in the axial direction (side cover 22 side) toward a downstream portion 38 located on the inner side in the axial direction (rotor core 32 side) than the upstream portion 37. In the present embodiment, the upstream portion 37 is provided at a position corresponding to an upper portion of the bearing 33, out of the end surfaces of the bearing 33 located on the outer side in the axial direction. The entire axially inner end surface of the bearing 33 is a downstream portion 38. Therefore, the cooling medium flowing through the bearing 33 moves at least from the upstream portion 37 to the downstream portion 38 in the axial direction, and a part of the cooling medium moves in the circumferential direction in the bearing 33 from the upper portion to the lower portion of the bearing 33.

(stator)

The stator 4 is disposed at a radial outer side with a space with respect to the rotor 3. An air gap G is formed between the stator 4 and the rotor 3. The stator 4 is formed in a ring shape. The outer peripheral portion of the stator 4 is fixed to the inner wall surface of the housing. The stator 4 includes a stator core 41 and a conductive member 42.

The stator core 41 is a laminated core formed by laminating a plurality of steel plates in the axial direction. The stator core 41 is formed in a ring shape with the axis C as the center. The stator core 41 has not-shown teeth and slots. The teeth protrude radially inward from the inner peripheral portion of the stator core 41. The teeth extend in the axial direction. The teeth are provided in plurality at intervals in the circumferential direction. The slots are disposed between circumferentially adjacent teeth.

The conductive member 42 is inserted into each slot. The conductive member 42 is, for example, a coil formed by winding a plurality of windings around teeth. An insulating paper, not shown, is provided between the conductive member 42 and the stator core 41. The conductive member 42 is attached to the stator core 41 in a state of being insulated from the stator core 41 by insulating paper. The conductive member 42 includes a through portion 45 inserted into the stator core 41 and extending in the axial direction, and bridging portions 46 protruding from the stator core 41 to both sides in the axial direction.

(covering Member)

Fig. 2 is a sectional view of the cover member 5 of the first embodiment.

The cover members 5 are provided in a pair on both sides in the axial direction with respect to the stator core 41 (see fig. 1). The pair of cover members 5 have the same structure. In the following description, the covering member 5 provided on the side cover 22 side is sometimes described in detail and the description of the covering member 5 provided on the side opposite to the side cover 22 is omitted.

As shown in fig. 1, the covering member 5 covers the lap portion 46 of the conductive member 42. The cover member 5 is fixed to the stator core 41 by adhesion. As shown in fig. 2, the cover member 5 is formed in an annular shape centered on the axis C when viewed from the axial direction. The cover member 5 has a conductive member cooling portion 6 and a bearing cooling portion 7.

As shown in fig. 1 and 2, the conductive member cooling portion 6 is provided so as to surround the periphery of the lap portion 46 of the conductive member 42. The conductive member cooling unit 6 has a function of cooling the lap portion 46 of the conductive member 42. The conductive member cooling portion 6 is formed in an annular shape. Specifically, the conductive member cooling portion 6 has an outer wall 11, an inner wall 12, and an end wall 13.

The outer wall 11 is provided at a position corresponding to the outer peripheral portion of the lap portion 46. The outer wall 11 is formed in an annular shape centered on the axis C.

The inner wall 12 is provided at a position corresponding to the inner peripheral portion of the lap portion 46. The inner wall 12 is formed in an annular shape coaxial with the outer wall 11 at a position radially inward of the outer wall 11. The bearing 33 and the holding portion 23 are disposed radially inward of the inner wall 12. The bearing 33 and the holding portion 23 are arranged at a distance from the inner wall 12 in the radial direction. The width of the inner wall 12 in the axial direction is larger than the width of the bearing 33 in the axial direction. In the present embodiment, the width dimension of the inner wall 12 in the axial direction is about 3 to 4 times the width dimension of the bearing 33 in the axial direction. The bearings 33 are provided at positions inward of both ends of the inner wall 12 in the axial direction.

The end wall 13 connects axially outer ends of the outer wall 11 and the inner wall 12 to each other. The conductive member cooling portion 6 is formed in a U-shaped cross section with the outer wall 11, the inner wall 12, and the end wall 13 opening toward the rotor core 32 in the axial direction when viewed in the radial direction. Gaps 10 through which a cooling medium can flow are provided between the outer wall 11, the inner wall 12, and the end wall 13 and the lap portions 46 of the conductive member 42.

In a state where the rotating electric machine 1 is horizontally arranged, a communication hole, not shown, is provided in a lower portion of the conductive member cooling portion 6. The communication hole penetrates the conductive member cooling portion 6. The communication hole communicates the gap 10 between the conductive member cooling portion 6 and the lap portion 46 with the outside of the covering member 5. The coolant is supplied into the gap 10 through the communication holes to cool the lap portion 46.

As shown in fig. 2, the bearing cooling unit 7 is provided radially inward of the conductive member cooling unit 6. The bearing cooling unit 7 has a function of cooling a bearing 33 that rotatably supports a rotary shaft 31 (see fig. 1). Specifically, the bearing cooling portion 7 includes the cooling medium receiving portion 14, the protruding wall portion 15, the cooling medium guide portion 16, the cooling medium supply portion 17, and the cooling medium guide surface 51.

The cooling medium receiving portion 14 protrudes radially inward from the inner wall 12 of the conductive member cooling portion 6. In other words, the cooling medium receiving portion 14 extends from the inner wall 12 of the conductive member cooling portion 6 toward the bearing 33 side in the radial direction. The cooling medium receiving portion 14 is formed integrally with the inner wall 12 of the conductive member cooling portion 6. The coolant receiving portion 14 is formed in an annular shape that is continuous in the circumferential direction. In the present embodiment, the radially inner tip portion of the coolant receiving portion 14 extends in the radial direction to a position corresponding to the outer peripheral portion of the holding portion 23. The cooling medium receiver 14 is provided axially inward of the downstream portion 38 of the bearing 33. Specifically, the cooling medium receiver 14 is provided so as to be spaced further inward in the axial direction than the axially inner end surface of the bearing 33. The coolant receiving portion 14 restricts the outflow of the coolant flowing through the bearing 33 from the upstream portion 37 toward the downstream portion 38 to the outside of the cover member 5.

The projecting wall portion 15 is provided axially outward of the coolant receiving portion 14. Specifically, the projecting wall portion 15 is provided so as to be spaced axially outward from an axially outward end surface of the bearing 33. The projecting wall portion 15 projects radially inward from the inner wall 12 of the conductive member cooling portion 6. In other words, the projecting wall portion 15 extends from the inner wall 12 of the conductive member cooling portion 6 toward the bearing 33 side in the radial direction. The protruding wall portion 15 is formed integrally with the inner wall 12 of the conductive member cooling portion 6. The projecting wall portion 15 is formed in an annular shape continuous in the circumferential direction. The radially inner front end portion of the projecting wall portion 15 extends radially to the same position as the front end portion of the cooling medium receiving portion 14. The front end of the projecting wall 15 contacts the outer peripheral surface of the holding portion 23.

A space 50 surrounded by the inner wall 12 of the conductive member cooling portion 6, the outer peripheral surface of the holding portion 23, the cooling medium receiving portion 14, and the projecting wall portion 15 is formed radially outward of the outer peripheral portion of the holding portion 23. Space portion 50 is formed in a ring shape centered on axis C when viewed in the axial direction. The space portion 50 is continuous with the downstream portion 38 of the bearing 33. In space portion 50, the cooling medium can flow in the circumferential direction from cooling medium receiving portion 14 toward upstream portion 37 of bearing 33. The outer peripheral surface of the holding portion 23 and the inner peripheral surface of the inner wall 12 of the conductive member cooling portion 6 face the space portion 50, and serve as a cooling medium guide surface 51 that guides the cooling medium toward the upstream portion 37 of the bearing 33 by a centrifugal force when the rotary shaft 31 rotates.

Cooling medium guide 16 is provided above space 50. The cooling medium guide portion 16 guides the cooling medium from the cooling medium receiver 14 toward the upstream portion 37 of the bearing 33 in the axial direction. The cooling medium guide portion 16 is provided above the holding portion 23. Specifically, the cooling medium guide portion 16 protrudes radially inward from the inner wall 12 of the conductive member cooling portion 6. The cooling medium guide portion 16 is formed integrally with the inner wall 12 of the conductive member cooling portion 6. The cooling medium guide 16 is formed in a plate shape intersecting the circumferential direction of the rotating shaft 31. The cooling medium guide 16 is inclined from the inside to the outside in the axial direction as going from the upstream side to the downstream side in the rotation direction of the rotary shaft 31 (hereinafter, sometimes referred to as the rotation direction of the bearing 33). The axially outer end of the cooling medium guide 16 is connected to the projecting wall 15. The axially inner end of the cooling medium guide 16 is connected to the cooling medium receiver 14.

The cooling medium supply portion 17 is provided at a position corresponding to the upstream portion 37 of the bearing 33 in the holding portion 23. The cooling medium supply unit 17 supplies the cooling medium guided by the cooling medium guide unit 16 to the upstream portion 37 of the bearing 33. In the present embodiment, the cooling medium supply portion 17 is a hole formed in the holding portion 23. The cooling medium supply portion 17 penetrates the holding portion 23 in the radial direction. In a state where the rotating electric machine 1 is horizontally arranged, the cooling medium supply portion 17 extends in the vertical direction. The cooling medium supply portion 17 is provided on the upstream side of the cooling medium guide portion 16 in the rotation direction of the bearing 33 in the circumferential direction. Thereby, the cooling medium supply unit 17 supplies the cooling medium flowing through the space portion 50 and reaching the cooling medium guide unit 16 to the bearing 33.

(operation of Cooling Medium in bearing Cooling part)

Next, the operation of the cooling medium in the bearing cooling portion 7 of the cover member 5 will be described with reference to fig. 1 and 2.

First, when the rotor 3 rotates, the cooling medium in the housing 2 is lifted upward by an oil pump, a gear, or the like, and a part of the cooling medium is supplied to the bearing 33. The cooling medium supplied to the bearing 33 flows through the bearing 33 from the outside toward the inside in the axial direction, and is then discharged from the downstream portion 38 of the bearing 33 to the outside of the bearing 33 (see arrow S1 in fig. 2).

Part of the cooling medium discharged from bearing 33 passes through cooling medium receiving portion 14 and is discharged to the outside of space portion 50. The cooling medium discharged to the outside of the space portion 50 moves downward of the housing 2 by gravity, and then is lifted upward again by an oil pump, a gear, or the like.

On the other hand, the remaining part of the cooling medium discharged from the bearing 33 is captured by the cooling medium receiving portion 14 of the cover member 5, and thus the outflow from the space portion 50 is suppressed and remains in the space portion 50. At this time, a force toward the outside in the radial direction acts on the cooling medium discharged from the bearing 33 due to a centrifugal force, and a force toward the downstream side in the rotational direction acts due to the rotation of the bearing 33. Therefore, the cooling medium remaining in the space portion 50 is transferred to the cooling medium guide surface 51 provided in the holding portion 23 or the inner wall 12 and moves in the circumferential direction (see arrow S2 in fig. 2).

Next, the cooling medium moves from below to above in space portion 50 along the circumferential direction, and reaches the upper portion of space portion 50 (see arrow S3 in fig. 2). The cooling medium reaching the upper portion of space portion 50 is weakened in the circumferential direction by the increase in potential energy and the contact with cooling medium guide portion 16. The cooling medium with reduced potential flows into the cooling medium supply portion 17 by its own weight, and flows through the cooling medium supply portion 17 to be supplied to the upstream portion 37 of the bearing 33 (see arrow S4 in fig. 2). The cooling medium supplied to the upstream portion 37 of the bearing 33 flows again from the upstream portion 37 toward the downstream portion 38 in the bearing 33.

In this way, the cooling medium circulating in the bearing 33 is circulated by the cover member 5 and supplied again to the upstream portion 37 of the bearing 33, so that a sufficient amount of the cooling medium can be supplied to the bearing 33 at all times. Thus, the covering member 5 suppresses the seizure of the bearing 33 due to the decrease in the amount of the cooling medium supplied to the bearing 33. In particular, the cover member 5 suppresses the seizure at the inner peripheral portion of the bearing 33 caused by the cooling medium concentrating on the outer peripheral portion of the bearing 33 by the centrifugal force and the shortage of the cooling medium at the inner peripheral portion of the bearing 33.

(action, Effect)

Next, the operation and effect of the rotating electric machine 1 will be described.

According to the rotating electrical machine 1 of the present embodiment, in the rotating electrical machine 1 horizontally arranged, a space portion 50 that is continuous with the downstream portion 38 of the bearing 33 and through which the cooling medium can flow is formed in the outer peripheral portion of the holding portion 23 that holds the bearing 33. In space portion 50, cooling medium guide portion 16 is provided for guiding the cooling medium from cooling medium receiving portion 14 toward upstream portion 37 of bearing 33. Thus, the cooling medium that has flowed through the bearing 33 and discharged from the bearing 33 toward the downstream portion 38 is circulated through the space portion 50 by the cooling medium guide portion 16, and is supplied again to the upstream portion 37 of the bearing 33 by the cooling medium supply portion 17. By reusing a part of the cooling medium in this way, the amount of the cooling medium supplied to the bearing 33 can be ensured much more at all times. Therefore, the cooling medium can be stably supplied, and seizure of the bearing 33 can be suppressed.

The cooling medium receiving portion 14 is provided at a position axially inward of the downstream portion 38 of the bearing 33, and restricts the amount of the cooling medium flowing through the bearing 33 from flowing out of the space portion 50 to the outside. This can suppress the cooling medium discharged from the downstream portion 38 of the bearing 33 from entering the air gap G between the rotor 3 and the stator 4. Therefore, the amount of the cooling medium supplied to the bearing 33 can be increased while suppressing the occurrence of NV of the rotating electric machine 1 caused by the cooling medium entering the air gap G.

Therefore, the rotating electric machine 1 can be provided in which seizure of the bearing 33 can be suppressed without causing NV.

The outer peripheral surface of the holding portion 23 is a cooling medium guide surface 51 that guides the cooling medium toward the upstream portion 37 of the bearing 33 by centrifugal force. The cooling medium transferred to the upstream portion 37 of the bearing 33 by the cooling medium guide surface 51 flows from the upstream portion 37 toward the downstream portion 38 in the bearing 33, thereby cooling and lubricating the bearing 33. This can suppress the seizure of the bearing 33. Since the outer peripheral surface of the holding portion 23 that holds the bearing 33 can be used as the cooling medium guide surface 51, it is not necessary to add a new member for guiding the cooling medium to the upstream portion 37 of the bearing 33. Therefore, the cooling medium can be efficiently supplied to the bearing 33 by the centrifugal force while suppressing an increase in the number of components.

Like the outer peripheral surface of the holding portion 23, the inner peripheral surface of the inner wall 12 of the covering member 5 serves as a cooling medium guide surface 51. The inner wall 12 of the cover member 5 is a member constituting the conductive member cooling portion 6, and the lap portion 46 can be efficiently cooled by the conductive member cooling portion 6. In this way, the inner peripheral surface of the inner wall 12 provided to cool the lap portion 46 can be used as the cooling medium introducing surface 51, and therefore, it is not necessary to add a new member to introduce the cooling medium to the upstream portion 37 of the bearing 33. Therefore, the cooling medium can be efficiently supplied to the bearing 33 by the centrifugal force while suppressing an increase in the number of components.

The space 50 is formed in an annular shape with the axis C as the center, and the cooling medium can flow through the space 50. Thereby, the cooling medium moves in the annular circumferential direction in space portion 50 by the centrifugal force obtained when bearing 33 flows. The cooling medium moving in the circumferential direction reaches the cooling medium supply portion 17, and then is supplied to the upstream portion 37 of the bearing 33. Thereby, the cooling medium cools and lubricates the bearing 33. Therefore, the coolant can be stably supplied from the coolant receiving portion 14 to the upstream portion 37 of the bearing 33 by effectively utilizing the centrifugal force of the coolant, and seizure of the bearing 33 can be effectively suppressed.

The cooling medium guide portion 16 is provided above the holding portion 23. The centrifugal force of the cooling medium is minimized at the upper portion of the holding portion 23. The cooling medium guide portion 16 is provided so as to intersect the circumferential direction. Therefore, the cooling medium that moves in the circumferential direction in space 50 by the centrifugal force reaches cooling medium guide 16 in a state where the potential head of the upper portion of holding portion 23 is weakened. The cooling medium that has reached the cooling medium guide portion 16 is guided to the upstream portion 37 of the bearing 33 while being restricted from moving in the circumferential direction by the cooling medium guide portion 16. This can suppress scattering of the cooling medium and supply the cooling medium to the upstream portion 37 of the bearing 33 more efficiently than in the case where the cooling medium reaches the cooling medium guide portion 16 in a state where the cooling medium is very strong.

The rotating electrical machine 1 is provided with an annular covering member 5 that covers the lap portion 46 of the conductive member 42. Thereby, the periphery of the lap portion 46 is covered with the covering member 5. Therefore, for example, by supplying the cooling medium to the gap 10 between the covering member 5 and the lap portion 46, the cooling medium can be supplied to the entire lap portion 46, and the lap portion 46 can be cooled efficiently.

A space portion 50 is provided between the inner peripheral surface of the covering member 5 and the outer peripheral surface of the holding portion 23. This allows the space 50 to be formed without adding a new member. Therefore, the cooling medium can be stably supplied to the bearing 33 while suppressing an increase in the number of components.

The cooling medium receiving portion 14 protrudes radially inward from the inner peripheral surface of the cover member 5. In this way, since the covering member 5 is formed integrally with the cooling medium receiver 14, it is not necessary to add a new component in order to provide the cooling medium receiver 14. Therefore, the cooling medium can be stably supplied to the bearing 33 while suppressing an increase in the number of components.

(second embodiment)

Next, a second embodiment of the present invention will be described. Fig. 3 is a sectional view of the cover member 205 of the second embodiment. The present embodiment is different from the above-described embodiments in that the inner peripheral surface of the inner wall 12 of the covering member 205 is inclined.

In the present embodiment, the inner peripheral surface of the inner wall 12 of the cover member 5, that is, the cooling medium introducing surface 251 of the inner wall 12 is inclined such that the inner diameter increases as it goes from the downstream portion 38 side to the upstream portion 37 side of the axial bearing 33. The inclined cooling medium guide surfaces 251 are provided continuously along the entire circumference in the circumferential direction.

According to the present embodiment, the cooling medium discharged from the bearing 33 is thereby transferred by the centrifugal force on the inner circumferential surface of the cover member 5 to move in the circumferential direction, and moves from the downstream portion 38 side to the upstream portion 37 side of the bearing 33 in the axial direction along the inclined inner circumferential surface (cooling medium inducing surface 251). Therefore, the cooling medium can be more efficiently supplied to the upstream portion 37 of the bearing 33.

(third embodiment)

Next, a third embodiment of the present invention will be described. Fig. 4 is a sectional view of the cover member 305 of the third embodiment. The present embodiment differs from the above-described embodiments in that a guide portion 352 is provided in the space portion 50.

In the present embodiment, the space portion 50 is provided with the induction portion 352. The guide portion 352 is a convex portion of the cover member 5 that protrudes radially inward from the inner peripheral surface of the inner wall 12. The inductive portion 352 is formed integrally with the inner wall 12. The guide portion 352 is formed in a spiral shape inclined from the downstream portion 38 side to the upstream portion 37 side of the bearing 33 in the axial direction as going from the upstream side to the downstream side in the rotational direction of the rotary shaft 31. Preferably, the inclination angle of the guiding portion 352 is set to an inclination angle such that the length dimension along the axial direction of the section of one circumferential circle is shorter than the dimension between the coolant receiving portion 14 and the projecting wall portion 15. In addition, a notch or the like through which the cooling medium can flow in the circumferential direction may be separately formed in the induction portion 352.

According to the present embodiment, the inducing portion 352 provided in the space portion 50 is inclined from the downstream portion 38 side to the upstream portion 37 side of the bearing 33 in the axial direction as going from the upstream side to the downstream side in the rotation direction of the rotary shaft 31. Therefore, when the cooling medium discharged from the bearing 33 moves in the circumferential direction along the rotation direction of the rotary shaft 31 in the space portion 50 by the centrifugal force, the cooling medium moves from the downstream portion 38 side to the upstream portion 37 side of the bearing 33 in the axial direction along the guide portion 352. Therefore, the cooling medium can be more efficiently supplied to the upstream portion 37 of the bearing 33.

The inductive portion 352 is a convex portion. This allows the induction portion 352 to be provided with a simple configuration, and the cooling medium to be efficiently supplied to the bearing 33.

(fourth embodiment)

Next, a fourth embodiment of the present invention will be described. Fig. 5 is a sectional view of the cover member 405 of the fourth embodiment. The present embodiment is different from the third embodiment described above in that the inducing portion 452 is a concave portion.

In the present embodiment, the space portion 50 is provided with the induction portion 452. The guide portion 452 is a recess portion of the cover member 405 that is recessed radially outward from the inner circumferential surface of the inner wall 12. The guide portion 452 is formed in a spiral shape inclined from the downstream portion 38 side to the upstream portion 37 side of the bearing 33 in the axial direction as going from the upstream side to the downstream side in the rotational direction of the rotary shaft 31. That is, the inducing portion 452 is a groove formed in the inner wall 12. The inclination angle of the inducing portion 452 in the fourth embodiment is the same as the inclination angle of the inducing portion 352 in the third embodiment.

According to the present embodiment, the concave portion is formed instead of the convex portion, and thereby the same operation and effect as those of the third embodiment can be obtained.

The width of the inducing portion 352 (concave portion) in the third embodiment and the groove width of the inducing portion 452 (concave portion) in the fourth embodiment are not limited to the illustrated widths.

(fifth embodiment)

Next, a fifth embodiment of the present invention will be described. Fig. 6 is a sectional view of the cover member 505 of the fifth embodiment. The present embodiment differs from the above-described embodiments in that a pipe for supplying the cooling medium in space 50 to upstream portion 37 of bearing 33 is provided as the cooling medium supply portion.

In the present embodiment, the cooling medium supply unit 517 is a pipe that communicates the space portion 50 with the upstream portion 37 of the bearing 33. The cooling medium supply unit 517 supplies the cooling medium that has reached the upper portion of the space portion 50 to the upstream portion 37 of the bearing 33. An oil catcher 516 is provided on the downstream side in the rotation direction in the circumferential direction of the cooling medium supply unit 517. The oil catcher 516 has the same function as the cooling medium guide 16 in each of the above embodiments. In the present embodiment, the oil catcher 516 is provided to completely block the movement of the cooling medium in the circumferential direction after reaching the upper portion of the space portion 50.

According to the present embodiment, since the movement of the cooling medium in the circumferential direction is blocked by the oil catcher 516, the cooling medium can be efficiently flowed into the cooling medium supply unit 517 even when the momentum of the cooling medium is strong. The cooling medium supply unit 517 is a pipe. Therefore, the flow direction of the cooling medium captured by the oil catcher 516 can be easily set. Therefore, the cooling medium can be supplied to the upstream portion 37 of the bearing 33 more reliably.

The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

For example, in the above-described embodiment, the bearing 33 disposed on the side of the side cover 22 in the axial direction is described as an example, but it is preferable that a similar configuration is applied to a bearing disposed on the opposite side of the side cover 22 in the axial direction. In this case, for example, a second holding portion (not shown) protruding from the housing main body 21 toward the inside of the housing 2 may be provided. Alternatively, a cylindrical case main body 21 having openings on both sides in the axial direction and a pair of side covers 22 covering openings at both ends of the case main body 21 may be provided, and the holding portions 23 may be formed on the side covers 22. A separate member may be provided for the side cover 22 and the housing main body 21, and the holding portion 23 may be formed in these members.

The distal end of the coolant receiving portion 14 may extend radially inward of the outer peripheral portion of the holding portion 23. The distal end of the coolant receiving portion 14 may terminate outside the outer peripheral portion of the holding portion 23.

The stator 4 may be provided with a cooling passage (not shown) for flowing a cooling medium in the axial direction, for example. The cooling passage may communicate with the gap 10 provided in the conductive member cooling portion 6.

The cover member 5 may not have the conductive member cooling portion 6. That is, the outer wall 11 and the end wall 13 may not be present. However, the structure of the present embodiment in which the covering member 5 includes the conductive member cooling unit 6 and the bearing cooling unit 7 is advantageous in that the entire rotating electrical machine 1 can be cooled efficiently by actively cooling not only the bearing 33 but also the land portion 46 of the conductive member 42.

In addition, the components in the above embodiments may be replaced with known components as appropriate without departing from the scope of the present invention, and the above embodiments may be combined as appropriate.