JP2021177675A - Rotor and rotary electric machine - Google Patents

Abstract

To provide a rotor which is capable of supplying a coolant from a shaft center passage to the inside of a rotor core and improves the fixture strength of the rotor core, and a rotary electric machine provided with the rotor.SOLUTION: A rotor comprises a shaft which is rotated around an axis O, and a rotor core 6 which is rotated integrally with the shaft. The shaft includes: a shaft center passage which extends in the axial direction and in which a coolant can be circulated; and a coolant supply path which extends in the radial direction and communicates the shaft center passage with the outer peripheral part of the shaft. The rotor core 6 includes: a first core 21 including a radial passage 25 communicating with the coolant supply path and extending in the radial direction; and a second core 22 which is laminated with the first core 21 in the axial direction and includes an axial passage 33 communicating with the radial passage 25 and extending in the axial direction. A press-fit part 34 in which the shaft is press-fitted is provided in the inner peripheral part of the second core 22, and a non-press-fit part 26 which is disposed without press-fitting of the shaft is provided in the inner peripheral part of the first core 21.SELECTED DRAWING: Figure 3

Description

The present invention relates to a rotor and a rotary electric machine.

Conventionally, a rotor configuration of a rotary electric machine having a shaft having an axial center flow path is known. In these rotors, various techniques have been proposed in which a core flow path through which a refrigerant can flow is formed inside the rotor core, and the rotor is cooled by supplying the refrigerant of the axial center flow path to the core flow path.

For example, Patent Document 1 describes a shaft having an axial flow path, an intermediate core plate that communicates with the axial center flow path and is provided with a notch that extends in the radial direction to allow a refrigerant to flow, and communicates with the notch. A configuration of a rotor including a slitted core plate provided with a slit for flowing a refrigerant in the rotor core is disclosed. According to the technique described in Patent Document 1, the refrigerant can be distributed in the order of the axial flow path in the shaft, the notch of the intermediate core plate, and the slit of the core plate with a slit.

JP-A-2017-701148

However, in the technique described in Patent Document 1, the rotor core and the shaft are fixed by press-fitting the shaft into the inner peripheral surface of the intermediate core plate having a notch formed on the shaft side. .. As described above, when the notch is formed on the inner peripheral surface of the rotor core, the strength of the inner peripheral portion of the rotor core is likely to decrease as compared with the case where the notch is not provided. Therefore, in the technique described in Patent Document 1, there is a possibility that the rotor core is deformed due to the stress at the time of press-fitting the shaft, and the fixing strength of the rotor core to the shaft is lowered.

Therefore, an object of the present invention is to provide a rotor capable of supplying a refrigerant from the axial flow path to the inside of the rotor core and having improved fixing strength of the rotor core, and a rotary electric machine provided with the rotor.

In order to solve the above problems, the rotor according to the invention according to claim 1 (for example, the rotor 4 in the first embodiment) has a shaft (for example, an axis O in the first embodiment) that rotates around an axis (for example, an axis O in the first embodiment). , The shaft 5) in the first embodiment and a rotor core (for example, the rotor core 6 in the first embodiment) attached to the outer peripheral portion of the shaft and rotating integrally with the shaft. (For example, the axial flow path 15 in the first embodiment) extending along the axial direction of the shaft and allowing the refrigerant to flow, and the axial flow path and the axial flow path extending along the radial direction of the shaft. The rotor core has a refrigerant supply path (for example, the refrigerant supply path 16 in the first embodiment) that communicates with the outer peripheral portion of the shaft, and the rotor core has a diameter that communicates with the refrigerant supply path and extends along the radial direction. A first core (for example, the first core 21 in the first embodiment) having a directional flow path (for example, the radial flow path 25 in the first embodiment) is laminated with the first core in the axial direction, and the said A second core (for example, the second core 22 in the first embodiment) having an axial flow path (for example, the axial flow path 33 in the first embodiment) that communicates with the radial flow path and extends along the axial direction. ), And the inner peripheral portion of the second core is provided with a press-fitting portion (for example, the press-fitting portion 34 in the first embodiment) into which the shaft is press-fitted. Is characterized in that a non-press-fitting portion (for example, the non-press-fitting portion 26 in the first embodiment) is provided in which the shaft is arranged without being press-fitted.

The rotor according to the second aspect of the present invention is characterized in that the inner diameter of the second core before press fitting into the shaft is smaller than the inner diameter of the first core.

を満たすように設定されることを特徴としている。 Further, in the rotor according to the invention according to claim 3, the length of the first core along the axial direction is defined as the first core shaft length B (for example, the first core shaft length B in the first embodiment). The length of the rotor core along the axial direction is defined as the rotor core axial length D (for example, the rotor core axial length D in the first embodiment), and the safety factor for slipping of the first core in the circumferential direction with respect to the shaft is the slip safety factor. When Z (for example, the slip safety factor Z in the first embodiment), the first core shaft length B, the rotor core shaft length D, and the slip safety factor Z are

It is characterized in that it is set to satisfy.

The rotor according to the fourth aspect of the invention is characterized by including a regulating member (for example, a regulating member 8 in the first embodiment) that regulates the movement of the first core with respect to the shaft in the circumferential direction. There is.

Further, in the rotor according to the fifth aspect of the present invention, the rotor core has through holes (for example, the first through hole 24 and the second through hole 32 in the first embodiment) penetrating along the axial direction. The regulatory member is formed such that the through hole formed in the first core (for example, the first through hole 24 in the first embodiment) and the through hole formed in the second core (for example, the first through hole). It is characterized in that it is inserted into the second through hole 32) in the embodiment.

Further, in the rotor according to the invention of claim 6, an insulating spacer (for example, in the first embodiment) is provided in the gap between the through hole and the regulating member (for example, the gap 39 in the first embodiment). It is characterized in that a spacer 40) is provided.

Further, the rotor according to the invention according to claim 7 is characterized in that the spacer is provided outside the restricting member in the radial direction.

Further, in the rotor according to the invention of claim 8, the regulating member (for example, the regulating member 208 in the second embodiment) is arranged adjacent to the first core in the axial direction and described above. It has an engaging portion (for example, an engaging portion 209 in the second embodiment) that engages with the first core, and the inner peripheral portion of the restricting member is press-fitted into the shaft.

Further, the rotor according to the invention according to claim 9 is characterized in that the regulating member is a non-magnetic material.

The rotary electric machine according to the invention according to claim 10 (for example, the rotary electric machine 1 in the first embodiment) is a stator (for example, the first embodiment) arranged at intervals between the above-mentioned rotor and the outer peripheral portion of the rotor. It is characterized by including a stator 3) in the form.

According to the rotor according to claim 1 of the present invention, the shaft has an axial flow path and a refrigerant supply path. The rotor core has a first core having a radial flow path and a second core having an axial flow path. The radial flow path of the first core communicates with the refrigerant supply path of the shaft, and the axial flow path of the second core communicates with the radial flow path of the first core. Therefore, the refrigerant in the axial flow path flows in the order of the refrigerant supply path, the radial flow path, and the axial flow path, and is supplied to the inside of the rotor core. As a result, the rotor core can be cooled.
A non-press-fitting portion is provided on the inner peripheral portion of the first core so that the shaft is not press-fitted. Since the radial flow path of the first core opens on the inner peripheral side where the shaft is located, by providing a non-press-fitting portion on the inner peripheral portion of the first core, the first core is deformed or damaged due to press-fitting. Occurrence can be suppressed. On the other hand, a press-fitting portion into which the shaft is press-fitted is provided on the inner peripheral portion of the second core. Since the axial flow path of the second core extends along the axial direction, the inner peripheral portion of the second core has higher rigidity than the inner peripheral portion of the first core. Therefore, by press-fitting the shaft into the inner peripheral portion of the second core, the second core can be firmly fixed to the shaft. Further, since the second core and the first core are laminated in the axial direction, the first core and the second core can be fixed by arranging the first core between the pair of second cores, for example. As a result, the first core can be indirectly fixed to the shaft even when the non-press-fitting portion is provided on the inner peripheral portion of the first core. Therefore, slippage of the first core with respect to the shaft in the circumferential direction can be suppressed.
Therefore, it is possible to provide a rotor in which the refrigerant can be supplied from the axial flow path to the inside of the rotor core and the fixing strength of the rotor core is improved.

According to the rotor according to claim 2 of the present invention, the inner diameter of the second core before the shaft press-fitting is smaller than the inner diameter of the first core. Therefore, when the shaft is press-fitted into the inner peripheral portion (press-fitting portion) of the second core, the inner diameter of the second core is slightly expanded by receiving the pressing force from the shaft. On the other hand, since the pressing force from the shaft does not act on the non-press-fitted portion of the first core, the inner diameter of the first core does not increase. As a result, only the inner diameter of the second core is expanded by press-fitting the shaft. In particular, when the inner diameter of the first core is set so that the non-press-fitted portion can come into contact with the shaft, the inner diameter of the first core after press-fitting can be made equal to the inner diameter of the second core. As a result, it is possible to prevent the refrigerant from entering the gap between the non-press-fitted portion of the first core and the shaft. Therefore, it is possible to suppress a decrease in the flow efficiency of the refrigerant from the axial flow path to the inside of the rotor core.

According to the rotor according to claim 3 of the present invention, the first core shaft length B, the rotor core shaft length D, and the slip safety factor Z are set so as to satisfy the equation (1). This makes it possible to secure a desired slip safety factor of the first core with respect to the shaft. Therefore, even when the first core having the non-press-fitted portion that is not press-fitted into the shaft is provided as a part of the rotor core, the slip of the first core with respect to the shaft can be suppressed. Equation (1) represents the relationship between the thickness of the entire rotor core (rotor core shaft length D), the thickness of the first core (first core shaft length B), and the slip safety factor. Therefore, as long as the equation (1) is satisfied, the axial position of the first core with respect to the entire rotor core can be set to an arbitrary position while ensuring a desired slip safety factor. In particular, when the end face plates are arranged at both ends of the rotor core, the first core can be arranged at the axial end of the rotor core. Therefore, the rotor can have an improved degree of freedom in design regarding the arrangement of the first core.

According to claim 4 of the present invention, the rotor includes a regulating member. The regulating member regulates the circumferential movement of the first core with respect to the shaft. Thereby, the slip of the first core can be effectively suppressed. Therefore, the fixing strength of the rotor core can be further increased.

According to the rotor according to claim 5 of the present invention, the regulating member is inserted into the through hole formed in the first core and the through hole formed in the second core. As a result, the relative movement of the first core and the second core along the circumferential direction is restricted. In other words, the first core and the second core rotate integrally. The second core is firmly fixed to the shaft by a press-fitting portion. Therefore, slippage of the first core and the second core with respect to the shaft can be suppressed, and the rotor core can be firmly fixed to the shaft.

According to the rotor according to claim 6 of the present invention, an insulating spacer is provided in the gap between the through hole and the regulating member. As a result, since the spacer plays the role of a cushioning material when the rotor rotates, it is possible to suppress wear or breakage between the regulating member and the rotor core when stress or the like due to vibration or centrifugal force during rotor rotation occurs. Therefore, the relative movement between the first core and the second core can be stably suppressed.

According to the rotor according to claim 7 of the present invention, the spacer is provided outside the regulating member in the radial direction. As a result, when the centrifugal force during rotor rotation acts on the regulating member, it is possible to suppress wear or chipping of the regulating member due to the regulating member being pressed against the rotor core.

According to claim 8 of the present invention, the regulating member is arranged adjacent to the first core in the axial direction. Thereby, for example, when the first core is arranged at the axial end of the rotor core, the first core can be sandwiched between the regulating member and the second core. The inner peripheral portion of the regulating member is press-fitted into the shaft, and the regulating member has an engaging portion that engages with the first core. As a result, the shaft and the regulating member rotate integrally, and the relative movement of the regulating member and the first core in the circumferential direction is restricted by the engaging portion. Therefore, the slip of the first core with respect to the shaft can be suppressed. Therefore, the rotor core can be firmly fixed to the shaft, especially when the first core is arranged at the end of the rotor core.

According to the rotor according to claim 9 of the present invention, the regulating member is a non-magnetic material. As a result, the fixing strength of the rotor core can be increased while suppressing the influence of the provision of the regulating member on the magnetic characteristics of the rotor.

According to the rotary electric machine according to claim 10 of the present invention, since the rotor is provided, the rotor can be effectively cooled by supplying the refrigerant of the axial center flow path to the inside of the rotor core. Further, the fixing strength of the rotor can be increased by suppressing deformation or breakage of the first core at the time of press-fitting the shaft.
Therefore, it is possible to provide a high-performance rotary electric machine provided with a rotor capable of supplying a refrigerant from the axial flow path to the inside of the rotor core and improving the fixing strength of the rotor core.

FIG. 3 is a partial cross-sectional view of a rotary electric machine according to the first embodiment. The perspective view of the rotor which concerns on 1st Embodiment. Exploded view of the rotor according to the first embodiment. The front view of the first core which concerns on 1st Embodiment. The front view of the 2nd core which concerns on 1st Embodiment. A partially enlarged view of the through hole according to the first embodiment. The perspective view of the rotor which concerns on 2nd Embodiment. FIG. 7 is a perspective view of a rotor in which the regulating member in FIG. 7 is omitted.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment)
(Rotating machine)
FIG. 1 is a partial cross-sectional view of the rotary electric machine 1 according to the first embodiment. In FIG. 1, the thickness of the first core 21 in the rotor core 6 is exaggerated for explanation.
The rotary 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 applicable not only to a traveling motor, but also to a power generation motor, a motor for other purposes, and a rotary electric machine 1 (including a generator) other than for vehicles.
The rotary electric machine 1 includes a case 2, a stator 3, and a rotor 4.

(Case)
The case 2 houses the stator 3 and the rotor 4. A refrigerant (not shown) is housed inside the case 2. The stator 3 and the rotor 4 described above are arranged inside the case 2 in a state where a part of the stator 3 and the rotor 4 is immersed in the refrigerant. As the refrigerant, ATF (Automatic Transmission Fluid) or the like, which is a hydraulic oil used for lubrication of a transmission, power transmission, or the like, is preferably used.
In the following description, the direction along the axis O, which is the center of rotation of the rotor 4, is simply referred to as the axial direction, the direction orthogonal to the axis O is referred to as the radial direction, and the direction around the axis O may be referred to as the circumferential direction.

(Stator)
The stator 3 is fixed to the inner wall surface of the case 2. The stator 3 is formed in an annular shape. The stator 3 has a stator core 11 and a coil 12.
The stator core 11 is a laminated core formed by laminating a plurality of steel plates in the axial direction. The stator core 11 is formed in an annular shape centered on the axis O. The outer peripheral portion of the stator core 11 is fixed to the inner wall surface of the case 2. The stator core 11 has teeth (not shown) protruding inward in the radial direction from the inner peripheral portion of the stator core 11. A plurality of teeth are provided in the circumferential direction. Slots (not shown) are provided between each teeth.

The coil 12 is inserted into the slot of the stator core 11. The coil 12 is mounted on the stator core 11, for example, by inserting a plurality of copper wire segments into the slots. The coil 12 has a coil insertion portion 12a inserted into the slot of the stator core 11 and coil ends 12b protruding from the stator core 11 on both sides in the axial direction.

(Rotor)
The rotor 4 is formed in a columnar shape centered on the axis O. The rotors 4 are arranged at intervals in the radial direction with respect to the stator 3. The rotor 4 includes a shaft 5, a rotor core 6, a permanent magnet 7, and a regulating member 8 (see FIG. 2).

The shaft 5 is formed in a cylindrical shape centered on the axis O. The shaft 5 is rotatably supported with respect to the case 2 via a bearing 17 attached to the case 2. The shaft 5 rotates about the axis O. The shaft 5 has an axial flow path 15 and a refrigerant supply path 16.
The axial flow path 15 extends inside the shaft 5 along the axial direction. The axial center flow path 15 is formed coaxially with the axis O. Refrigerant can flow through the axial flow path 15.
The refrigerant supply path 16 extends inside the shaft 5 along the radial direction. The radial inner end of the refrigerant supply path 16 is connected to the axial flow path 15. The radial outer end of the refrigerant supply path 16 is open to the outer peripheral portion of the shaft 5. A plurality of refrigerant supply paths 16 (six in the present embodiment) are provided in the circumferential direction. The refrigerant in the axial flow path 15 can flow into the refrigerant supply path 16.

FIG. 2 is a perspective view of the rotor 4 according to the first embodiment, and FIG. 3 is an exploded view of the rotor 4 according to the first embodiment. In FIGS. 2 and 3, the shaft 5 is not shown.
The rotor core 6 is fixed to the outer peripheral surface of the shaft 5 (see FIG. 1). The rotor core 6 is formed in an annular shape centered on the axis O. The rotor core 6 can rotate integrally with the shaft 5 around the axis O. The length (rotor core shaft length) of the entire rotor core 6 along the axial direction is D. The rotor core 6 is formed of a plurality of core members divided in the axial direction. Specifically, the rotor core 6 has a first core 21 and a pair of second cores 22.

FIG. 4 is a front view of the first core 21 according to the first embodiment.
As shown in FIGS. 1 and 2, the first core 21 is provided at the central portion of the rotor core 6 in the axial direction. As shown in FIG. 2, the length of the first core 21 along the axial direction (first core axial length) is B. As shown in FIGS. 3 and 4, the first core 21 is formed in an annular shape coaxial with the axis O. The first core 21 has a first magnet insertion hole 23, a first through hole 24, a radial flow path 25, and a non-press-fitting portion 26.

The first magnet insertion hole 23 is provided on the outer peripheral portion of the first core 21. The first magnet insertion hole 23 penetrates the first core 21 in the axial direction. A plurality of first magnet insertion holes 23 are provided in the circumferential direction. When viewed from the axial direction, each first magnet insertion hole 23 is formed in a rectangular shape. Of the plurality of first magnet insertion holes 23, a pair of first magnet insertion holes 23 adjacent to each other in the circumferential direction are formed in a V shape that is separated from each other in the circumferential direction toward the outside in the radial direction when viewed from the axial direction. ing.

The first through hole 24 is provided inside the first magnet insertion hole 23 in the radial direction. The first through hole 24 penetrates the first core 21 in the axial direction. The first through hole 24 is provided between the ends of the adjacent first magnet insertion holes 23 located inside in the radial direction in the circumferential direction. A plurality of first through holes 24 (6 in this embodiment) are provided in the circumferential direction. When viewed from the axial direction, the first through hole 24 is formed in a triangular shape with the apex facing outward in the radial direction. The first through hole 24 is provided, for example, in a place where the magnetic characteristics of the rotor 4 are not affected, that is, a place where the passage of magnetic flux is desired to be suppressed, a place where the amount of passage of magnetic flux is small, and the like.

The radial flow path 25 is provided between the adjacent first through holes 24 in the circumferential direction. A plurality of radial flow paths 25 are provided at equal intervals along the circumferential direction (six in the present embodiment). The radial flow path 25 penetrates the first core 21 in the axial direction. Seen from the axial direction, the radial flow path 25 extends along the radial direction. The radial outer end of the radial flow path 25 is terminated at a position between the first magnet insertion hole 23 and the first through hole 24 in the radial direction. A refrigerant reservoir 27 having a width wider than that of the radial flow path 25 is connected to the radial outer end of the radial flow path 25. The refrigerant reservoir 27 is formed in a triangular shape with the apex facing outward in the radial direction.

The radial inner end of the radial flow path 25 is open to the inner peripheral side of the first core 21. With the shaft 5 inserted into the inner peripheral portion of the first core 21, the radial inner end of the radial flow path 25 is connected to the radial outer end of the refrigerant supply path 16 of the shaft 5. There is. The refrigerant in the refrigerant supply path 16 can flow into the radial flow path 25.

The non-press-fitting portion 26 is provided on the inner peripheral portion of the first core 21. The shaft 5 is arranged on the inner peripheral portion of the first core 21 without being press-fitted. In other words, the inner peripheral portion of the first core 21 that faces the shaft 5 when the shaft 5 is inserted without being press-fitted is the non-press-fit portion 26. In the non-press-fitting portion 26, the first core 21 is in contact with the shaft 5.

As shown in FIGS. 2 and 3, the second core 22 is axially laminated with the first core 21. In the present embodiment, the second core 22 is arranged on both sides in the axial direction with respect to the first core 21. That is, the second core 22 is provided at both ends of the rotor core 6 in the axial direction. As shown in FIG. 2, the lengths (second core axial lengths) of the second cores 22 along the axial direction are A and C, respectively. In this embodiment, the two second cores 22 have the same configuration. That is, in this embodiment, A = C. In the following description, one of the two second cores 22 may be described in detail, and the other second core 22 may be omitted.

FIG. 5 is a front view of the second core 22 according to the first embodiment.
The second core 22 is formed in an annular shape coaxial with the axis O. The second core 22 has a second magnet insertion hole 31, a second through hole 32, an axial flow path 33, and a press-fitting portion 34.

The second magnet insertion hole 31 is provided on the outer peripheral portion of the second core 22. The second magnet insertion hole 31 penetrates the second core 22 in the axial direction. A plurality of second magnet insertion holes 31 are provided in the circumferential direction. When viewed from the axial direction, each second magnet insertion hole 31 is formed in a rectangular shape. Of the plurality of second magnet insertion holes 31, a pair of second magnet insertion holes 31 adjacent to each other in the circumferential direction are formed in a V shape that is separated from each other in the circumferential direction toward the outside in the radial direction when viewed from the axial direction. ing. With the first core 21 and the second core 22 laminated, the second magnet insertion hole 31 of the second core 22 is located at the same position as the first magnet insertion hole 23 of the first core 21 when viewed from the axial direction. It is provided.

The second through hole 32 is provided inside the second magnet insertion hole 31 in the radial direction. The second through hole 32 penetrates the second core 22 in the axial direction. The second through hole 32 is provided between the ends of the adjacent second magnet insertion holes 31 located inside in the radial direction in the circumferential direction. A plurality of second through holes 32 (6 in this embodiment) are provided in the circumferential direction. When viewed from the axial direction, the second through hole 32 is formed in a triangular shape with the apex facing outward in the radial direction. With the first core 21 and the second core 22 laminated, the second through hole 32 of the second core 22 is provided at the same position as the first through hole 24 of the first core 21 when viewed from the axial direction. ing.

The axial flow path 33 is provided between the adjacent second through holes 32 in the circumferential direction. A plurality of axial flow paths 33 (six in this embodiment) are provided in the circumferential direction. The axial flow path 33 is provided between the second magnet insertion hole 31 and the second through hole 32 in the radial direction. The axial flow path 33 extends along the axial direction by penetrating the first core 21 in the axial direction. When viewed from the axial direction, the axial flow path 33 is formed in a triangular shape with the apex facing outward in the radial direction. In a state where the first core 21 and the second core 22 are laminated, the axial flow path 33 of the second core 22 is provided at the same position as the refrigerant pool portion 27 of the first core 21. Therefore, the axial flow path 33 of the second core 22 communicates with the radial flow path 25 of the first core 21. The refrigerant in the radial flow path 25 can flow into the axial flow path 33.

The press-fitting portion 34 is provided on the inner peripheral portion of the second core 22. A shaft 5 is press-fitted and fixed to the inner peripheral portion of the second core 22. In other words, the inner peripheral portion of the second core 22 where the shaft 5 is press-fitted is the press-fitting portion 34. The second core 22 is firmly fixed to the shaft 5 by providing the press-fitting portion 34. The press-fitting portion 34 is formed without providing a notch (radial flow path 25) that opens on the inner peripheral portion side like the non-press-fitting portion 26 of the first core 21. Therefore, the inner peripheral portion of the second core 22 provided with the press-fitting portion 34 has higher rigidity than the inner peripheral portion of the first core 21 provided with the non-press-fitting portion 26.
The inner diameter of the second core 22 before the shaft 5 is press-fitted is smaller than the inner diameter of the first core 21. When the shaft 5 is press-fitted into the second core 22, the inner diameter of the second core 22 is increased. As a result, the inner diameter of the second core 22 and the inner diameter of the first core 21 are the same when the shaft 5 is press-fitted.

As shown in FIG. 2, the first core 21 and the second core 22 thus formed are laminated in the order of the second core 22, the first core 21, and the second core 22 along the axial direction. As a result, the rotor core 6 is formed. The rotor core shaft length D of the rotor core 6 is the sum of the first core shaft length B and the two second core shaft lengths A and C (D = A + B + C).
Here, the safety factor for slipping of the first core 21 with respect to the shaft 5 in the circumferential direction is defined as the slip safety factor Z. At this time, in order for the slip safety factor Z of the first core 21 with respect to the shaft 5 to be 1 times, the first core shaft length B, the rotor core shaft length D, and the slip safety factor Z satisfy the following equation (2). ..

From equation (2), the following equation (3) is derived.

Therefore, the first core shaft length B, the rotor core shaft length D, and the slip safety factor Z are set so as to satisfy the following equation (1). In the equation (1), the slip safety factor Z is a value of 1 or more (Z ≧ 1).

By setting the first core shaft length B so as to satisfy the equation (1), it is possible to form the rotor 4 in which the slip safety factor Z set at the time of design is ensured.

As shown in FIG. 3, the permanent magnet 7 is inserted into the first magnet insertion hole 23 formed in the first core 21 and the second magnet insertion hole 31 formed in the second core 22. The permanent magnet 7 extends inside the rotor core 6 along the axial direction. The length along the axial direction of the permanent magnet 7 is formed to be the same as the length along the axial direction of the rotor core 6 (rotor core axial length D). One permanent magnet 7 is provided over the first core 21 and the second core 22. The permanent magnet 7 is fixed to the rotor core 6 with, for example, an adhesive (not shown).

The regulating member 8 is attached to at least the first core 21. The regulating member 8 regulates the movement of the first core 21 with respect to the shaft 5 in the circumferential direction. In the present embodiment, the regulating member 8 is a pin member inserted into the first through hole 24 formed in the first core 21 and the second through hole 32 formed in the second core 22. The regulating member 8 extends along the axial direction. The length of the regulating member 8 along the axial direction is formed to be the same as the length of the rotor core 6 along the axial direction (rotor core axial length D). The regulating member 8 is provided over the first core 21 and the two second cores 22. A plurality of regulating members 8 (six in this embodiment) are provided in the circumferential direction. The regulating member 8 is made of a non-magnetic material. More preferably, the regulating member 8 is made of an insulating and non-magnetic material. In the present embodiment, the regulating member 8 is formed of a resin material that is both an insulator and a non-magnetic material. The regulating member 8 is fixed to the first core 21 and the second core 22, and makes it impossible for the first core 21 and the second core 22 to rotate relative to each other around the axis C. As a result, the regulating member 8 indirectly makes the first core 21 and the shaft 5 unable to rotate relative to each other via the second core 22 firmly fixed to the shaft 5.

FIG. 6 is a partially enlarged view of the through holes 24 and 32 according to the first embodiment.
When viewed from the axial direction, the regulating member 8 is formed in a triangular shape with the apex facing outward in the radial direction. The outer shape of the regulating member 8 is slightly smaller than the inner shape of the first through hole 24 and the second through hole 32 (hereinafter, may be simply referred to as through holes 24 and 32). Therefore, in a state where the regulating member 8 is inserted into the through holes 24 and 32, a gap 39 is formed between the regulating member 8 and the rotor core 6. The gap 39 is provided between two sides of the regulating member 8 located on the outer side in the radial direction and the rotor core 6. The gap 39 is filled with an insulating spacer 40. The spacer 40 is provided on the outer side in the radial direction with respect to the regulating member 8. The spacer 40 is made of an insulating and non-magnetic material. Specifically, the spacer 40 is made of a resin material. The spacer 40 fills the gap 39 between the regulating member 8 and the rotor core 6, and fixes the regulating member 8 to the rotor core 6.

(Distribution route of refrigerant circulating in the rotor)
Next, in the above-mentioned rotary electric machine 1, the distribution path of the refrigerant circulating in the rotor 4 will be described.
First, the refrigerant supplied to the shaft center flow path 15 by a pump or the like (not shown) circulates in the shaft center flow path 15 in the axial direction, and in the refrigerant supply path 16 due to the centrifugal force when the rotor is rotated four times. And move outward in the radial direction. Next, the refrigerant that has reached the radial outer end of the refrigerant supply path 16 flows into the radial flow path 25 provided in the first core 21. The refrigerant in the radial flow path 25 moves further outward in the radial direction in the first core 21 due to centrifugal force.

The refrigerant that has reached the radial outside of the radial flow path 25 is stored in the refrigerant reservoir 27 and then flows into the axial flow paths 33 of the second core 22 located on both sides of the first core 21 due to internal pressure. do. The refrigerant in the axial flow path 33 cools the rotor core 6 by flowing from the inside to the outside in the axial direction.
Next, the refrigerant is discharged to the outside of the rotor core 6 from both ends in the axial direction of the rotor core 6. The discharged refrigerant circulates in the case 2 and is supplied to the axial flow path 15 again.

(Action, effect)
Next, the actions and effects of the rotor 4 and the rotary electric machine 1 described above will be described.
According to the rotor 4 of the present embodiment, the shaft 5 has an axial flow path 15 and a refrigerant supply path 16. The rotor core 6 has a first core 21 having a radial flow path 25 and a second core 22 having an axial flow path 33. The radial flow path 25 of the first core 21 communicates with the refrigerant supply path 16 of the shaft 5, and the axial flow path 33 of the second core 22 communicates with the radial flow path 25 of the first core 21. .. Therefore, the refrigerant in the axial center flow path 15 circulates in the order of the refrigerant supply path 16, the radial flow path 25, and the axial flow path 33, and is supplied to the inside of the rotor core 6. As a result, the rotor core 6 can be cooled.
A non-press-fitting portion 26 is provided on the inner peripheral portion of the first core 21 so that the shaft 5 is not press-fitted. Since the radial flow path 25 of the first core 21 opens toward the inner peripheral portion where the shaft 5 is located, the first core 21 by press-fitting is provided by providing the non-press-fitting portion 26 on the inner peripheral portion of the first core 21. It is possible to suppress the occurrence of deformation and breakage of the. On the other hand, a press-fitting portion 34 into which the shaft 5 is press-fitted is provided on the inner peripheral portion of the second core 22. Since the axial flow path 33 of the second core 22 extends along the axial direction, the inner peripheral portion of the second core 22 has higher rigidity than the inner peripheral portion of the first core 21. Therefore, by press-fitting the shaft 5 into the inner peripheral portion of the second core 22, the second core 22 can be firmly fixed to the shaft 5. Further, since the second core 22 and the first core 21 are laminated in the axial direction, for example, by arranging the first core 21 between the pair of second cores 22, the first core 21 and the second core 22 are arranged. And can be fixed. As a result, the first core 21 can be indirectly fixed to the shaft 5 even when the non-press-fitting portion 26 is provided on the inner peripheral portion of the first core 21. Therefore, slipping of the first core 21 with respect to the shaft 5 in the circumferential direction can be suppressed.
Therefore, it is possible to provide the rotor 4 in which the refrigerant can be supplied from the axial flow path 15 to the inside of the rotor core 6 and the fixing strength of the rotor core 6 is improved.

The inner diameter of the second core 22 before press-fitting the shaft 5 is smaller than the inner diameter of the first core 21. Therefore, when the shaft 5 is press-fitted into the inner peripheral portion (press-fitting portion 34) of the second core 22, the inner diameter of the second core 22 is slightly expanded by receiving the pressing force from the shaft 5. On the other hand, since the pressing force from the shaft 5 does not act on the non-press-fitted portion 26 of the first core 21, the inner diameter of the first core 21 is not expanded. As a result, only the inner diameter of the second core 22 is expanded by press-fitting the shaft 5. In particular, when the inner diameter of the first core 21 is set so that the non-press-fit portion 26 can come into contact with the shaft 5, the inner diameter of the first core 21 after press-fitting and the inner diameter of the second core 22 can be made equal. can. As a result, it is possible to prevent the refrigerant from entering the gap between the non-press-fitted portion 26 of the first core 21 and the shaft 5. Therefore, it is possible to suppress a decrease in the flow efficiency of the refrigerant from the axial flow path 15 toward the inside of the rotor core 6.

The first core shaft length B, the rotor core shaft length D, and the slip safety factor Z are set so as to satisfy the equation (1). As a result, the desired slip safety factor Z of the first core 21 can be secured with respect to the shaft 5. Therefore, even when the first core 21 having the non-press-fitted portion 26 that is not press-fitted into the shaft 5 is provided as a part of the rotor core 6, the slip of the first core 21 with respect to the shaft 5 can be suppressed. Equation (1) represents the relationship between the thickness of the entire rotor core 6 (rotor core shaft length D), the thickness of the first core 21 (first core shaft length B), and the slip safety factor Z. Therefore, as long as the equation (1) is satisfied, the axial position of the first core 21 with respect to the entire rotor core 6 can be set to an arbitrary position while ensuring a desired slip safety factor Z. In particular, when the end face plates are arranged at both ends of the rotor core 6, the first core 21 can be arranged at the axial end of the rotor core 6. Therefore, the rotor 4 can have an improved degree of freedom in design regarding the arrangement of the first core 21.

The rotor 4 includes a regulating member 8. The regulating member 8 regulates the movement of the first core 21 with respect to the shaft 5 in the circumferential direction. Thereby, the slip of the first core 21 can be effectively suppressed. Therefore, the fixing strength of the rotor core 6 can be further increased.

The regulating member 8 is inserted into the first through hole 24 formed in the first core 21 and the second through hole 32 formed in the second core 22. As a result, the relative movement of the first core 21 and the second core 22 along the circumferential direction is restricted. In other words, the first core 21 and the second core 22 rotate integrally. The second core 22 is firmly fixed to the shaft 5 by the press-fitting portion 34. Therefore, the slip of the first core 21 and the second core 22 with respect to the shaft 5 can be suppressed, and the rotor core 6 can be firmly fixed to the shaft 5.

An insulating spacer 40 is provided in the gap 39 between the through holes 24 and 32 and the regulating member 8. As a result, the spacer 40 plays the role of a cushioning material when the rotor is rotated four times, so that when stress or the like due to vibration or centrifugal force when the rotor is rotated four times is generated, wear or chipping between the regulating member 8 and the rotor core 6 is suppressed. can. Therefore, the relative movement between the first core 21 and the second core 22 can be stably suppressed.

The spacer 40 is provided on the outer side in the radial direction with respect to the regulating member 8. As a result, when the centrifugal force during the rotation of the rotor 4 acts on the regulating member 8, it is possible to suppress wear or chipping of the regulating member 8 due to the regulating member 8 being pressed against the rotor core 6.

The regulating member 8 is a non-magnetic material. As a result, the fixing strength of the rotor core 6 can be increased while suppressing the influence of the provision of the regulating member 8 on the magnetic characteristics of the rotor 4.
Further, the through holes 24 and 32 into which the regulating member 8 is inserted are provided in a portion of the rotor core 6 where the influence of the magnetic flux is small. As a result, even when the regulation member 8 made of a non-magnetic material is arranged, the influence on the magnetic flux due to the provision of the regulation member 8 can be suppressed. Therefore, the performance of the rotor 4 can be maintained in a high state.

According to the rotary electric machine 1 of the present embodiment, since the rotor 4 described above is provided, the rotor 4 can be effectively cooled by supplying the refrigerant of the axial center flow path 15 to the inside of the rotor core 6. Further, the fixing strength of the rotor 4 can be increased by suppressing deformation or breakage of the first core 21 when the shaft 5 is press-fitted.
Therefore, it is possible to provide a high-performance rotary electric machine 1 provided with a rotor 4 capable of supplying a refrigerant from the axial center flow path 15 to the inside of the rotor core 6 and improving the fixing strength of the rotor core 6.

(Second Embodiment)
Next, a second embodiment according to the present invention will be described. FIG. 7 is a perspective view of the rotor 204 according to the second embodiment. FIG. 8 is a perspective view of the rotor 204 in which the regulation member 208 (end face plate) in FIG. 7 is omitted. In the following description, the same components as those in the first embodiment described above will be designated by the same reference numerals, and the description thereof will be omitted as appropriate. This embodiment is different from the above-described embodiment in that an end face plate is provided as the regulating member 8.

In the present embodiment, the first core 21 and the second core 22 are laminated in the order of the first core 21, the second core 22, and the second core 22 along the axial direction to form the rotor core 206. doing. That is, the first core 21 is provided at the axial end of the rotor core 206.
Further, in the present embodiment, the regulation member 208 is an end face plate arranged at an end portion of the rotor core 206. The regulating member 208 is arranged adjacent to the first core 21 in the axial direction. The regulating member 208 is formed in an annular shape coaxial with the rotor core 206. The outer diameter of the regulating member 208 is the same as the outer diameter of the rotor core 206. A shaft 5 is press-fitted and fixed to the inner peripheral portion of the regulating member 208. The regulating member 208 has an engaging portion 209 that engages with the first core 21. Specifically, the engaging portion 209 is a protruding portion protruding from the regulating member 208 toward the first core 21 in the axial direction. The engaging portion 209 is engaged with the first through hole 24 of the first core 21. As a result, the engaging portion 209 disables the relative rotation between the regulating member 208 and the first core 21.

According to this embodiment, the regulating member 208 is arranged adjacent to the first core 21 in the axial direction. Thereby, for example, when the first core 21 is arranged at the axial end of the rotor core 206, the first core 21 can be sandwiched between the regulating member 208 and the second core 22. The inner peripheral portion of the regulating member 208 is press-fitted into the shaft 5, and the regulating member 208 has an engaging portion 209 that engages with the first core 21. As a result, the shaft 5 and the regulating member 208 rotate integrally, and the engaging portion 209 regulates the relative movement of the regulating member 208 and the first core 21 in the circumferential direction. Therefore, the slip of the first core 21 with respect to the shaft 5 can be suppressed. Therefore, the rotor core 206 can be firmly fixed to the shaft 5 particularly when the first core 21 is arranged at the end of the rotor core 206.

The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in each of the above-described embodiments, the configuration in which the two second cores 22 are formed so that the shaft lengths A and C of the second cores have the same lengths is described, but the present invention is not limited to this. The second core shaft length A of one of the two second cores 22 and the second core shaft length C of the other of the two second cores 22 may be different.
The rotor core 6 may have, for example, three or more second cores 22. The rotor core 6 may have a plurality of first cores 21.

In the non-press-fitting portion 26 of the first core 21, the first core 21 and the shaft 5 may be arranged in a non-contact state.
The material of the regulating member 8 may be formed of a non-magnetic metal material including stainless steel and aluminum.
In the first embodiment, the number of the plurality of regulating members 8 provided in the circumferential direction, the number of the radial flow paths 25, the number of the refrigerant supply paths 16, and the like are not limited to the number of the above-described embodiments.

In each of the above-described embodiments, through holes 24 and 32 are formed in the rotor core 6 at a portion avoiding the magnetic path, and a non-magnetic regulating member 8 is inserted into the through holes 24 and 32. Not limited to. For example, a through hole may be formed in a portion of the rotor core 6 where the magnetic flux is desired to pass, and a magnetic regulating member 8 may be inserted into the through hole. However, since the influence on the magnetic characteristics of the rotor 4 can be further suppressed, through holes 24 and 32 are formed in places where magnetic flux does not pass, and the non-magnetic regulating member 8 is inserted into the through holes 24 and 32 as described above. The configuration of the embodiment has an advantage.
Further, for example, a magnetic flux control hole (flux barrier) formed in advance in the rotor core 6 in order to restrict the passage of magnetic flux may be used as a through hole. In this case, since it is not necessary to separately form the through holes 24 and 32 for arranging the regulating member 8, additional machining is not required and the number of steps during manufacturing can be reduced.

As the regulating member 8, the pin member in the first embodiment and the end face plate in the second embodiment may be used in combination.
In the first embodiment, end face plates may be separately provided at both ends of the rotor core 6.
In the second embodiment, as a method of fixing the regulating member 208 and the first core 21, a fixing method using a key groove and a key member (both not shown) may be applied.
In each of the above-described embodiments, the IPM motor in which the permanent magnet 7 is arranged inside the rotor 4 has been described as an example, but the present invention may be applied to an SPM motor in which the permanent magnet 7 is arranged on the outer peripheral surface of the rotor 4.

In addition, it is possible to replace the components in the above-described embodiments with well-known components as appropriate without departing from the spirit of the present invention, and the above-described embodiments may be combined as appropriate.

1 Rotating electric machine 3 Stator 4 Rotor 5 Shaft 6,206 Rotor core 8,208 Regulatory member 15 Axial center flow path 16 Refrigerant supply path 21 First core 22 Second core 24 First through hole (through hole)
25 Radial flow path 26 Non-press-fitted portion 32 Second through hole (through hole)
33 Axial flow path 34 Press-fitting part 39 Void 40 Spacer 209 Engaging part B First core shaft length D Rotor core shaft length O Axis line Z Slip safety factor

Claims (10)

A shaft that rotates around the axis and
A rotor core attached to the outer peripheral portion of the shaft and rotating integrally with the shaft,
With
The shaft
An axial flow path that extends along the axial direction of the axis and allows the refrigerant to flow through,
A refrigerant supply path that extends along the radial direction of the shaft and communicates the axial flow path and the outer peripheral portion of the shaft.
Have,
The rotor core
A first core having a radial flow path that communicates with the refrigerant supply path and extends along the radial direction.
A second core that is laminated in the axial direction with the first core and has an axial flow path that communicates with the radial flow path and extends along the axial direction.
With
A press-fitting portion into which the shaft is press-fitted is provided on the inner peripheral portion of the second core.
A rotor characterized in that a non-press-fitting portion is provided on the inner peripheral portion of the first core so that the shaft is not press-fitted. The rotor according to claim 1, wherein the inner diameter of the second core before press fitting into the shaft is smaller than the inner diameter of the first core. The length of the first core along the axial direction is defined as the first core axial length B.
The length of the rotor core along the axial direction is defined as the rotor core axial length D.
When the safety factor for slip of the first core in the circumferential direction with respect to the shaft is the slip safety factor Z,
The first core shaft length B, the rotor core shaft length D, and the slip safety factor Z are

The rotor according to claim 1 or 2, wherein the rotor is set to satisfy the above conditions. The rotor according to any one of claims 1 to 3, further comprising a regulating member that regulates the movement of the first core in the circumferential direction with respect to the shaft. The rotor core is formed with a through hole penetrating along the axial direction.
The rotor according to claim 4, wherein the regulating member is inserted into the through hole formed in the first core and the through hole formed in the second core. The rotor according to claim 5, wherein an insulating spacer is provided in the gap between the through hole and the regulating member. The rotor according to claim 6, wherein the spacer is provided outside the restricting member in the radial direction. The regulating member has an engaging portion that is arranged adjacent to the first core in the axial direction and engages with the first core.
The rotor according to claim 4, wherein the inner peripheral portion of the regulating member is press-fitted into the shaft. The rotor according to any one of claims 4 to 8, wherein the regulating member is a non-magnetic material. The rotor according to any one of claims 1 to 9,
A stator arranged at intervals on the outer peripheral portion of the rotor,
A rotary electric machine characterized by being equipped with.

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