JP2014087122A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary electric machine that prevents a reduction in detection accuracy of rotational position detection means due to electromagnetic waves.SOLUTION: A rotary electric machine 1 includes a rotor 2, a stator 3, and a resolver (rotational position detection means) 4. The rotor 2 has a rotor shaft 21, and a rotor core 22 fixed to the rotor shaft 21. The stator 3 has: a stator core 31 that is disposed on a radially outer side of the rotor core 22; and stator coils 32 that are wound around the stator core 31. The resolver 4 is disposed at an axial end of the rotor 2, and detects rotational position of the rotor 2. A shield member 5 includes non-magnetic material, and is disposed in at least part of the space between the stator 3 and the resolver 4. The shield member 5 is fixed to the rotor shaft 21, and is axially positioned and fixed between the rotor core 22 and the resolver 4.

Description

  The present invention relates to a rotating electrical machine mounted on a vehicle such as a hybrid vehicle or an electric vehicle.

  A rotary electric machine such as a motor used in a hybrid vehicle, an electric vehicle, or the like includes, for example, a rotor having a rotor shaft and a rotor core fixed to the rotor shaft, a stator core disposed on the outer peripheral side of the rotor core, and a winding around the stator core. And a stator having a rotated stator coil. Further, a resolver (rotational position detecting means) for detecting the rotational position (rotational angle) of the rotor is disposed on one end side in the axial direction of the rotor.

Conventionally, there has been a problem that electromagnetic waves from a stator (particularly, a stator coil) enter the resolver, thereby reducing the detection accuracy of the resolver.
For example, Patent Document 1 discloses a rotating electrical machine in which a shield member that shields (shields) electromagnetic waves is provided between a rotor core and a resolver in order to reduce the influence of electromagnetic waves received by the resolver.

JP 2010-154710 A

  However, in the rotating electrical machine disclosed in Patent Document 1, the rotor core side of the resolver is not sufficiently covered with the shield member in consideration of assembly of parts such as a housing to which the shield member is fixed. For this reason, electromagnetic waves from the stator or the like may enter the resolver from a portion not covered with the shield member, and the resolver could not be sufficiently protected against the electromagnetic waves.

  The present invention has been made in view of such a background, and an object of the present invention is to provide a rotating electrical machine capable of suppressing a decrease in detection accuracy of a rotational position detecting means due to electromagnetic waves.

One aspect of the present invention is a rotor having a rotor shaft and a rotor core fixed to the rotor shaft;
A stator having a stator core disposed on the outer peripheral side of the rotor core, and a stator coil wound around the stator core;
A rotational position detecting means disposed on one end side in the axial direction of the rotor and detecting the rotational position of the rotor;
A shielding member made of a non-magnetic material is disposed at least partly between the stator and the rotational position detecting means,
The shielding member is fixed to an axial position of the rotor shaft between the rotor core and the rotational position detecting means (Claim 1).

  In the rotating electrical machine, a shielding member made of a non-magnetic material is disposed at least at a part between the stator and the rotational position detecting means. Therefore, the electromagnetic wave entering the rotational position detecting means from the stator (particularly the stator coil) can be shielded (shielded) by the shielding member disposed between them. Thereby, it can suppress that the detection accuracy of a rotation position detection means falls by electromagnetic waves.

  Further, the shielding member is fixed at an axial position between the rotor core and the rotational position detecting means in the rotor shaft. For this reason, as in the prior art, a shielding member may be disposed so as to block between the stator disposed on the outer peripheral side of the rotor core and the rotational position detecting means, as compared with the case where it is fixed to a housing or the like described later. It becomes easy. Thereby, the electromagnetic waves from the stator can be sufficiently shielded (shielded) by the shielding member, and the rotational position detecting means can be sufficiently protected from the electromagnetic waves.

  Thus, the rotary electric machine which can suppress the detection accuracy fall of the rotation position detection means by electromagnetic waves can be provided.

Sectional explanatory drawing which shows the structure of the rotary electric machine in Example 1. FIG. Sectional explanatory drawing which shows the process of assembling the components which comprise the rotary electric machine in Example 1. FIG. Sectional explanatory drawing which shows the structure of the rotary electric machine in Example 2. FIG. Sectional explanatory drawing which shows the structure of the rotary electric machine in Example 3. FIG. Sectional explanatory drawing which shows the structure of the rotary electric machine in Example 4. FIG.

  In the rotating electric machine, as the nonmagnetic material constituting the shielding member, for example, aluminum, copper, an alloy thereof, or the like can be used. Examples of the aluminum alloy that can be used include aluminum bending materials such as A5052, A6061, and A7075, aluminum die-cast materials such as ADC10 and ADC12, and aluminum castings such as AC2B and AC4C.

The rotational position detecting means is a resolver including a resolver rotor fixed to the rotor shaft and a resolver stator disposed to face the resolver rotor, and the resolver stator includes the rotor and the stator. It is a part of the housing which accommodates, Comprising: It can be set as the structure fixed to the cover part which covers the axial direction one side of the said resolver (Claim 2).
In this case, the shield member and the resolver rotor are fixed to the rotor shaft, and the cover portion is assembled with the resolver stator fixed to the cover portion, so that the shield member and the resolver can be easily assembled without causing interference. It can be performed.
The resolver rotor and the resolver stator may be opposed in the radial direction or may be opposed in the axial direction.

Further, it is desirable that the cover portion is made of a nonmagnetic material.
In this case, it is possible to shield (shield) the electromagnetic waves that enter the rotational position detecting means from the outside (particularly one end side in the axial direction). Thereby, the fall of the detection accuracy of the rotation position detection means by electromagnetic waves can further be suppressed.
In addition, as a nonmagnetic material which comprises the said cover part, aluminum, copper, these alloys, etc. can be used similarly to the said shielding member, for example.

Further, the cover portion has a projection portion that covers the radially outer side of the resolver, the resolver stator is fixed to the projection portion, and the shielding member and the projection portion overlap in the radial direction. (Claim 4).
In this case, electromagnetic waves that enter the rotational position detecting means from the outside (particularly radially outside) can be shielded (shielded) by the shielding member and the protrusions of the cover portion. Thereby, the fall of the detection accuracy of the rotation position detection means by electromagnetic waves can be suppressed further.

The shielding member may be provided with a magnetic member made of a magnetic material.
In this case, the leakage magnetic flux from the stator coil can be induced and absorbed by the magnetic member, and the leakage magnetic flux can be prevented from entering the rotational position detecting means. Thereby, it can suppress that the detection accuracy of a rotation position detection means falls by leakage magnetic flux.
In addition, as a magnetic body which comprises the said magnetic member, iron (structural steel, carbon steel, spring steel etc.) etc. can be used, for example.

The shield member may include a holding portion that covers a radially outer side of the magnetic member, and the magnetic member may be held radially inward of the holding portion. .
In this case, it is possible to prevent the magnetic member provided on the shielding member from being scattered by the centrifugal force generated by the rotation of the rotor by the holding portion that covers the radially outer side of the magnetic member.

The shielding member is provided with a refrigerant passage through which a refrigerant flows, and the refrigerant passage is formed with a discharge port for discharging the refrigerant, and the discharge port is connected to the stator core in the stator coil. It can be set as the structure opened to radial direction toward the coil end part protruded from the axial direction one end surface (Claim 7).
In this case, the centrifugal force generated by the rotation of the rotor can cause the refrigerant in the refrigerant passage of the shielding member to be discharged from the discharge port toward the coil end portion of the stator coil and be brought into contact with the coil end portion. Thereby, the stator coil which generate | occur | produces heat can be cooled efficiently.

In addition, it is desirable that the discharge port of the refrigerant passage is located radially outside the rotor core.
In this case, the distance between the discharge port of the refrigerant passage of the shielding member and the coil end portion of the stator coil can be reduced, and the refrigerant discharged from the discharge port can be sufficiently brought into contact with the coil end portion. Thus, the stator coil that generates heat can be cooled more efficiently.

Further, it is desirable that the discharge port of the refrigerant passage is located radially outside the inner peripheral surface of the stator core.
In this case, the distance between the discharge port of the refrigerant passage of the shielding member and the coil end portion of the stator coil can be made closer, and the refrigerant discharged from the discharge port can be sufficiently and reliably brought into contact with the coil end portion. . Thereby, the stator coil which generate | occur | produces heat can be cooled much more efficiently.

Example 1
An embodiment according to the rotating electrical machine will be described with reference to the drawings.
As shown in FIG. 1, the rotating electrical machine 1 of this example includes a rotor 2 having a rotor shaft 21 and a rotor core 22 fixed to the rotor shaft 21, and a stator core 31 and a stator core 31 disposed on the outer peripheral side of the rotor core 22. A stator 3 having a wound stator coil 32 and a resolver (rotational position detecting means) 4 that is disposed on one axial end side of the rotor 2 and detects the rotational position of the rotor 2 are provided.
A shielding member 5 made of a non-magnetic material is disposed at least partly between the stator 3 and the resolver 4. The shielding member 5 is fixed to the axial position between the rotor core 22 and the resolver 4 in the rotor shaft 21.
This will be described in detail below.

As shown in FIG. 1, the rotating electrical machine 1 of this example is used for a motor of a hybrid vehicle, an electric vehicle, or the like, and includes a rotor 2 and a stator 3.
The rotor 2 includes a cylindrical rotor shaft 21 and a cylindrical rotor core 22 fixed to the outer peripheral surface of the rotor shaft 21. The rotor shaft 21 is rotatably disposed in the housing 10 that accommodates the rotor 2 and the stator 3 via bearings 13 provided on the outer peripheral surfaces of both axial end portions 211 and 212 thereof. The rotor core 22 is formed by laminating a plurality of annular silicon steel plates in the axial direction X.

  The stator 3 includes a cylindrical stator core 31 disposed so as to cover the radially outer side of the rotor core 22, and a stator coil 32 wound around the stator core 31. The stator core 31 is configured by laminating a plurality of annular silicon steel plates in the axial direction X. The stator core 31 is fixed to the housing 10. The stator coil 32 has coil end portions 321 and 322 protruding from both axial end surfaces of the stator core 31.

As shown in the figure, a resolver 4 as a rotational position detecting means for detecting the rotational position (rotational angle) of the rotor 2 is disposed on one end side in the axial direction of the rotor 2.
The resolver 4 includes a cylindrical resolver rotor 41 fixed to the outer peripheral surface of the axial end portion 211 of the rotor shaft 21 and a resolver stator 42 disposed on the outer peripheral side of the resolver rotor 41. The resolver rotor 41 is configured by laminating a plurality of annular silicon steel plates in the axial direction X. The resolver stator 42 is fixed to a cover portion 12 of the housing 10 described later. The resolver stator 42 includes a cylindrical resolver stator core 421 disposed so as to cover the radially outer side of the resolver rotor 41, and a resolver stator coil 422 wound around the resolver stator core 421.

  The housing 10 includes a housing main body portion 11 that covers the other axial side X2 and the radially outer side of the rotor 2 and the stator 3, and a cover portion 12 that covers the one axial side X1. The cover part 12 consists of aluminum which is a nonmagnetic material. Moreover, the cover part 12 has the projection part 121 which covers the resolver 4 from the radial direction outer side. The projecting portion 121 projects in the axial direction X from the cover portion 12 toward the rotor core 22. A resolver stator 42 (resolver stator core 421) is fixed to the radially inner side surface of the protrusion 121.

As shown in the figure, a shielding member 5 made of aluminum which is a non-magnetic material is disposed between the stator 3 and the resolver 4.
The shielding member 5 includes an annular shielding body 51 extending in the radial direction from the outer peripheral surface of the rotor shaft 21 and a cylindrical shielding protrusion 52 projecting from the tip of the shielding body 51 to the one axial side X1. . The shielding main body 51 is fixed to the axial position between the rotor core 22 and the resolver 4 on the outer peripheral surface of the rotor shaft 21. The shielding main body 51 is disposed so as to shield between the rotor core 22 and the resolver 4. The shielding protrusion 52 is disposed so as to shield between the coil end portion 321 and the resolver 4 on one axial side X <b> 1 of the stator coil 32. Moreover, the shielding protrusion 52 and the protrusion 121 of the cover part 12 partially overlap in the radial direction.

The stator 3 and the resolver 4 are shielded by the shielding main body 51 and the shielding protrusion 52 of the shielding member 5.
Further, the resolver 4 is covered on one side X <b> 1 in the axial direction by the cover portion 12 of the housing 10. Further, the resolver 4 is covered on the other axial side X <b> 2 by the shielding main body 51 of the shielding member 5. Further, the resolver 4 is covered on the outer side in the radial direction by the projection 121 of the cover 12 and the shielding protrusion 52 of the shielding member 5.

Next, the assembly of the housing 10 in the rotating electrical machine 1 of this example will be briefly described.
In this example, first, as shown in FIG. 2, the resolver rotor 41 and the shielding member 5 of the resolver 4 are fixed to the rotor shaft 21 accommodated in the housing body 11. Further, the resolver stator 42 of the resolver 4 is fixed to the protrusion 121 of the cover portion 12 of the housing 10.
Next, the cover 12 is assembled to the housing main body 11 so as to cover the one axial side X <b> 1 of the housing main body 11.
Thereby, the rotary electric machine 1 shown in FIG. 1 is obtained.

Next, the effect in the rotary electric machine 1 of this example is demonstrated.
In the rotating electrical machine 1 of this example, a shielding member 5 made of a non-magnetic material is disposed at least partially between the stator 3 and the resolver (rotational position detecting means) 4. Therefore, electromagnetic waves that enter the resolver 4 from the stator 3 (particularly the stator coil 32) can be shielded (shielded) by the shielding member 5 disposed between them. Thereby, it can suppress that the detection accuracy of the resolver 4 falls by electromagnetic waves.

  The shielding member 5 is fixed at an axial position between the rotor core 22 and the resolver 4 in the rotor shaft 21. Therefore, the shielding member 5 can be disposed so as to shield between the stator 3 and the resolver 4 disposed on the outer peripheral side of the rotor core 22 as compared with the conventional case where it is fixed to the housing 10 or the like. It becomes easy. Thereby, the electromagnetic waves from the stator 3 can be sufficiently shielded (shielded) by the shielding member 5, and the resolver 4 can be sufficiently protected from the electromagnetic waves.

  In this example, the rotational position detecting means is a resolver 4 including a resolver rotor 41 fixed to the rotor shaft 21 and a resolver stator 42 disposed on the outer peripheral side of the resolver rotor 41. The resolver stator 42 is a part of the housing 10 that houses the rotor 2 and the stator 3, and is fixed to the cover portion 12 that covers the one axial side X <b> 1 of the resolver 4. Therefore, the shield member 5 and the resolver rotor 41 are fixed to the rotor shaft 21, and the cover portion 12 is assembled in a state where the resolver stator 42 is fixed to the cover portion 12, thereby causing the shield member 5 and the resolver 4 to interfere with each other. And can be assembled easily.

  The cover 12 is made of a nonmagnetic material. Therefore, the electromagnetic waves that enter the resolver 4 from the outside (particularly one axial direction side X1) can be shielded (shielded) by the cover portion 12. Thereby, the detection accuracy fall of the resolver 4 by electromagnetic waves can further be suppressed.

  Further, the cover portion 12 has a protrusion 121 that covers the radially outer side of the resolver 4. The resolver stator 42 is fixed to the protrusion 121. Moreover, the shielding member 5 and the protrusion 121 are disposed so as to overlap in the radial direction. Therefore, electromagnetic waves that enter the resolver 4 from the outside (particularly radially outside) can be shielded (shielded) by the shielding member 5 and the protrusion 121 of the cover portion 12. Thereby, the detection accuracy fall of the resolver 4 by electromagnetic waves can be suppressed further.

  Thus, the rotary electric machine 1 which can suppress the detection accuracy fall of the resolver (rotation position detection means) 4 by electromagnetic waves can be provided.

(Example 2)
In this example, as shown in FIG. 3, the magnetic member 6 is provided on the shielding member 5.
In this example, as shown in the figure, the shielding member 5 is provided with a magnetic member 6 made of structural steel which is a magnetic body. Specifically, the shielding member 5 includes a holding portion (shielding protrusion) 52 that covers the radially outer side of the magnetic member 6. The magnetic member 6 is fixed to the radially inner side surface of the holding portion 52. That is, the magnetic member 6 is held inside the holding portion 52 in the radial direction.
Other basic configurations are the same as those in the first embodiment.

Next, the effect in the rotary electric machine 1 of this example is demonstrated.
In the rotary electric machine 1 of this example, the shielding member 5 is provided with a magnetic member 6 made of a magnetic material. Therefore, the leakage magnetic flux from the stator coil 32 can be induced and absorbed by the magnetic member 6, and the leakage magnetic flux can be prevented from entering the resolver 4. Thereby, it can suppress that the detection accuracy of the resolver 4 falls by leakage magnetic flux.

Further, the shielding member 5 has a holding portion (shielding protrusion) 52 that covers the outside in the radial direction of the magnetic member 6. The magnetic member 6 is held on the radially inner side of the holding portion 52. Therefore, it is possible to prevent the magnetic member 6 provided on the shielding member 5 from being scattered by the centrifugal force generated by the rotation of the rotor 2 by the holding portion 52 that covers the radially outer side of the magnetic member 6.
Other basic functions and effects are the same as those of the first embodiment.

(Example 3)
In this example, as shown in FIG. 4, the coolant passage 59 is provided in the shielding member 5.
In this example, as shown in the figure, the shielding member 5 is provided with a refrigerant passage 59 through which the refrigerant (cooling oil) A flows. Specifically, the refrigerant passage 59 is provided so as to penetrate the inside of the shielding main body 51 of the shielding member 5 in the radial direction.
The refrigerant passage 59 is formed with a discharge port 592 for discharging the refrigerant A. The refrigerant passage 59 communicates with a through hole 219 that penetrates the rotor shaft 21 in the radial direction. The refrigerant A is introduced into the refrigerant passage 59 from the inside of the rotor shaft 21 through the through hole 291.

As shown in the figure, the discharge port 592 of the refrigerant passage 59 opens in the radial direction toward the coil end portion 321 protruding from one axial end surface of the stator core 31 in the stator coil 32. Further, the discharge port 592 of the refrigerant passage 59 is on the radially outer side than the rotor core 22. Further, the discharge port 592 of the refrigerant passage 59 is located on the radially outer side than the inner peripheral surface 311 of the stator core 31.
Other basic configurations are the same as those in the first embodiment.

Next, the effect in the rotary electric machine 1 of this example is demonstrated.
In the rotary electric machine 1 of this example, the shielding member 5 is provided with a refrigerant passage 59 through which the refrigerant A flows. The refrigerant passage 59 is formed with a discharge port 592 for discharging the refrigerant A. Further, the discharge port 592 opens in the radial direction toward the coil end portion 321 protruding from one axial end surface of the stator core 31 in the stator coil 32. Therefore, the centrifugal force generated by the rotation of the rotor 2 causes the refrigerant A in the refrigerant passage 59 of the shielding member 5 to be discharged from the discharge port 592 toward the coil end portion 321 of the stator coil 32 and to contact the coil end portion 321. Can do. Thereby, the stator coil 32 that generates heat can be efficiently cooled.

  Further, the discharge port 592 of the refrigerant passage 59 is on the radially outer side than the rotor core 22. Therefore, the distance between the discharge port 592 of the refrigerant passage 59 of the shielding member 5 and the coil end portion 321 of the stator coil 32 is made closer, and the refrigerant A discharged from the discharge port 592 is sufficiently brought into contact with the coil end portion 321. Can do. Thus, the stator coil 32 that generates heat can be cooled more efficiently.

Further, the discharge port 592 of the refrigerant passage 59 is located on the radially outer side than the inner peripheral surface 311 of the stator core 31. Therefore, the distance between the discharge port 592 of the refrigerant passage 59 of the shielding member 5 and the coil end portion 321 of the stator coil 32 is made closer, and the refrigerant A discharged from the discharge port 592 is sufficiently and reliably supplied to the coil end portion 321. Can be contacted. Thereby, the stator coil 32 which generate | occur | produces heat can be cooled much more efficiently.
Other basic functions and effects are the same as those of the first embodiment.

(Example 4)
In this example, as shown in FIG. 5, one end plate 221 disposed on the rotor core 22 is used as the shielding member 5.
In this example, as shown in the figure, annular end plates 221 and 222 are disposed on both end surfaces of the rotor core 22 in the axial direction. The rotor core 22 is sandwiched from both sides in the axial direction X by a pair of end plates 221 and 222.
The end plate 221 disposed on one end surface in the axial direction of the rotor core 22 is the shielding member 5.
Other basic configurations and operational effects are the same as those in the first embodiment.

DESCRIPTION OF SYMBOLS 1 Rotating electrical machine 2 Rotor 21 Rotor shaft 22 Rotor core 3 Stator 31 Stator core 32 Stator coil 4 Resolver (rotation position detection means)
5 Shielding member

Claims (9)

A rotor having a rotor shaft and a rotor core fixed to the rotor shaft;
A stator having a stator core disposed on the outer peripheral side of the rotor core, and a stator coil wound around the stator core;
A rotational position detecting means disposed on one end side in the axial direction of the rotor and detecting the rotational position of the rotor;
A shielding member made of a non-magnetic material is disposed at least partly between the stator and the rotational position detecting means,
The rotating electrical machine, wherein the shielding member is fixed at an axial position between the rotor core and the rotational position detecting means on the rotor shaft.   2. The rotating electrical machine according to claim 1, wherein the rotational position detecting means is a resolver including a resolver rotor fixed to the rotor shaft and a resolver stator disposed to face the resolver rotor. The stator is a part of a housing that houses the rotor and the stator, and is fixed to a cover portion that covers one side in the axial direction of the resolver.   3. The rotating electrical machine according to claim 2, wherein the cover portion is made of a nonmagnetic material.   4. The rotating electrical machine according to claim 3, wherein the cover portion includes a protrusion that covers the resolver from a radially outer side, and the resolver stator is fixed to the protrusion, and the shielding member and the protrusion Is a rotating electrical machine characterized by being arranged so as to overlap in the radial direction.   The rotating electrical machine according to any one of claims 1 to 4, wherein the shielding member is provided with a magnetic member made of a magnetic material.   6. The rotating electrical machine according to claim 5, wherein the shielding member has a holding portion that covers the magnetic member from a radially outer side, and the magnetic member is held on a radially inner side of the holding portion. Rotating electric machine.   The rotating electrical machine according to any one of claims 1 to 6, wherein the shielding member is provided with a refrigerant passage through which a refrigerant flows, and an outlet for discharging the refrigerant is formed in the refrigerant passage. The rotating electrical machine is characterized in that the discharge port is opened in a radial direction toward a coil end portion protruding from one axial end surface of the stator core in the stator coil.   The rotating electrical machine according to claim 7, wherein the discharge port of the refrigerant passage is located radially outside the rotor core.   9. The rotating electrical machine according to claim 8, wherein the discharge port of the refrigerant passage is located radially outside the inner peripheral surface of the stator core.

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