JP2022155159A - Rotor and manufacturing method thereof - Google Patents

Abstract

To provide a rotor and a manufacturing method thereof that can reduce the stress on a cylindrical portion of a rotor core support member near a keyway when the cylindrical portion is fixed radially inwardly of the rotor core by interference fit.SOLUTION: A rotor 100 includes a rotor core 10 and a rotor hub 30 (rotor core support member). The rotor hub 30 includes a cylindrical portion 40 that supports rotor core 10 on the R1 side (radially inward) of the rotor core 10. The rotor core 10 includes a clearance fit portion 17 in which the cylindrical portion 40 is loosely fitted in the vicinity of a key portion 15 in the C direction (circumferential direction), and an interference fit portion 18 in which the cylindrical portion 40 is tightly fitted except in the vicinity of the key portion 15 in the C direction.SELECTED DRAWING: Figure 3

Description

The present invention relates to rotors and methods of manufacturing rotors.

2. Description of the Related Art Conventionally, a rotor is known that includes a rotor support member including a cylindrical portion that supports the rotor core radially inside the rotor core (see, for example, Patent Document 1).

The aforementioned Patent Document 1 discloses a rotor in which a flange-like member (rotor core support member) is fitted in a rotor core. In the rotor disclosed in Patent Document 1, the rotor core is provided with a key protruding radially inward. A cylindrical portion (hereinafter referred to as a cylindrical portion) of the flange-like member radially facing the rotor core is provided with a key groove so as to be recessed radially inward at a position facing the key. The key of the rotor core and the key groove of the flange member are engaged. In addition, in the cylindrical portion of the flange-shaped member, the portion where the key groove is provided so as to be recessed radially inward has a smaller radial thickness than the portion where the key groove is not provided.

Japanese Patent Application Laid-Open No. 2005-102460

Here, although not specified in Patent Document 1, in the conventional rotor as described in Patent Document 1, the cylindrical portion of the flange-shaped member (rotor core support member) is radially inward of the rotor core by interference fit. It may be pinned and fixed. In this case, an external force directed radially inward from the rotor core is applied to the cylindrical portion, and stress is generated in the cylindrical portion. However, in the rotor disclosed in Patent Document 1, the portion of the cylindrical portion of the flange-shaped member provided with the key groove so as to be recessed radially inward is thicker than the portion not provided with the key groove. Due to the smaller size, the strength (allowable stress) is smaller than that of the portion where the keyway is not provided. Therefore, when the cylindrical portion of the flange-shaped member (rotor core supporting member) is fixed radially inwardly of the rotor core by interference fit, the stress generated in the vicinity of the key groove (key groove portion) of the cylindrical portion can be reduced. It would be desirable to have a rotor and a method of manufacturing a rotor that is capable of

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and one object of the present invention is to provide a rotor core supporting member having a cylindrical portion fixed radially inwardly of a rotor core by an interference fit. An object of the present invention is to provide a rotor and a rotor manufacturing method capable of reducing stress generated in a portion of a cylindrical portion near a keyway portion.

To achieve the above object, a rotor according to a first aspect of the present invention includes a rotor core and a rotor core support member including a cylindrical portion that supports the rotor core radially inward of the rotor core, the rotor core radially inward. The cylindrical portion includes a key groove portion that is recessed radially inward at a position facing the key portion and engages with the key portion, and the rotor core includes a key portion in the circumferential direction of the rotor core. It includes a clearance fit portion in which the cylindrical portion is loosely fitted in the vicinity thereof, and an interference fit portion in which the cylindrical portion is tightly fitted except in the vicinity of the key portion in the circumferential direction. In the specification of the present application, "a portion of the cylindrical portion in the vicinity of the key portion (key groove portion)" includes, in the circumferential direction, the portion of the cylindrical portion provided with the key portion (key groove portion) and the key portion of the cylindrical portion. It is a concept that includes both the portion near the portion where the portion (key groove portion) is provided. In the specification of the present application, the term "interference fit" is a concept that includes both an interference fit and an intermediate fit, which is an intermediate state between the interference fit and the clearance fit.

In the rotor according to the first aspect of the present invention, as described above, the rotor core includes the clearance fitting portion in which the cylindrical portion is loosely fitted in the vicinity of the key portion in the circumferential direction. As a result, when the cylindrical portion is fitted to the rotor core, in the vicinity of the key portion in the circumferential direction, there is a gap in the radial direction between the clearance fitting portion of the rotor core and the portion of the cylindrical portion facing the clearance fitting portion Since the clearance is formed, the portion of the cylindrical portion that faces the clearance fitting portion is not subjected to an external force directed radially inward from the rotor core. As a result, when the cylindrical portion is fitted into the rotor core, it is possible to reduce the stress generated in the portion of the cylindrical portion in the vicinity of the key groove portion that faces the portion in the vicinity of the key portion provided with the clearance fit portion. In addition, in the rotor according to the first aspect, as described above, the rotor core includes the interference fit portion in which the cylindrical portion is tightly fit except in the vicinity of the key portion in the circumferential direction. As a result, the cylindrical portion of the rotor core support member can be fixed radially inwardly of the rotor core by the interference fit portion at a portion other than the vicinity of the key portion. As a result, when the cylindrical portion of the rotor core support member is fixed radially inwardly of the rotor core by an interference fit, the stress generated in the portion of the cylindrical portion near the keyway portion can be reduced. The effect of this stress reduction has already been confirmed by a simulation conducted by the inventor of the present application.

In order to achieve the above object, a rotor manufacturing method according to a second aspect of the present invention provides a rotor including a rotor core and a rotor core supporting member including a cylindrical portion that supports the rotor core radially inside the rotor core. In the manufacturing method, a rotor core including a key portion projecting radially inward is fitted with a cylindrical portion including a key groove portion provided so as to be recessed radially inwardly at a position facing the key portion and engaged with the key portion. The fitting step is a step of performing clearance fitting in the vicinity of the key portion in the circumferential direction of the rotor core and interference fitting in areas other than the vicinity of the key portion in the circumferential direction.

In the method of manufacturing a rotor according to the second aspect of the present invention, as described above, the fitting step is a step of loose fitting in the vicinity of the key portion in the circumferential direction of the rotor core. As a result, in the fitting step, in the vicinity of the key portion in the circumferential direction, there is a gap in the radial direction between the portion of the rotor core that is loosely fitted and the portion of the cylindrical portion that faces the portion of the rotor core that is loosely fitted. Since the gap is formed, no external force directed radially inward from the rotor core is applied to the portion of the cylindrical portion that faces the portion that is loosely fitted. As a result, as in the case of the rotor in the first aspect, when the cylindrical portion is fitted into the rotor core, it is generated in the portion of the cylindrical portion near the key groove portion that faces the portion near the key portion that is loosely fitted in the cylindrical portion. Stress can be reduced. Further, in the rotor manufacturing method according to the second aspect, as described above, the fitting step is a step of performing interference fitting in areas other than the vicinity of the key portion in the circumferential direction. As a result, in the fitting step, the cylindrical portion of the rotor core support member can be fixed radially inward of the rotor core by interference fitting in a portion other than the vicinity of the key portion. As a result, similar to the rotor in the first aspect, when the cylindrical portion of the rotor core supporting member is fixed radially inwardly of the rotor core by an interference fit, the portion of the cylindrical portion near the keyway portion is affected. Stress can be reduced.

According to the present invention, as described above, when the cylindrical portion of the rotor core supporting member is fixed radially inwardly of the rotor core by an interference fit, the stress generated in the portion of the cylindrical portion near the keyway portion is reduced. It is possible to provide a method for manufacturing a rotor and a rotor core that can achieve this.

1 is a cross-sectional view showing part of a vehicle drive system that includes a rotor according to one embodiment; FIG. FIG. 3 is an axial cross-sectional view of the rotor core and cylindrical portion of the rotor according to one embodiment; 3 is a partially enlarged sectional view of FIG. 2; FIG. FIG. 4 is a diagram showing a manufacturing flow of a rotor according to one embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

[Rotor configuration]
The configuration of a rotor 100 according to one embodiment will be described with reference to FIGS. 1 to 3. FIG.

In the following description, the axial direction, radial direction and circumferential direction of the rotor 100 (rotor core 10 (see FIG. 1)) are defined as Z direction, R direction and C direction, respectively. Also, one side and the other side in the Z direction are defined as the Z1 side and the Z2 side, respectively. Also, one side (radial direction inner side) and the other side (radial direction outer side) in the R direction are defined as the R1 side and the R2 side, respectively.

(Overall configuration of rotor)
As shown in FIG. 1 , the rotor 100 constitutes part of the rotating electric machine 102 together with the stator 101 . The rotating electric machine 102 is, for example, a motor, a generator, or a motor/generator. Rotor 100 and stator 101 are each formed in an annular shape. Rotor 100 is configured to rotate about rotation axis 90 . Rotor 100 is arranged on the R1 side of stator 101 so that the outer peripheral surface of rotor 100 and the inner peripheral surface of stator 101 face each other in the R direction. That is, the rotor 100 is configured as part of an inner rotor type rotating electric machine 102 .

The rotary electric machine 102 is provided in a vehicle drive device 103 as a drive source for driving the vehicle together with an engine (not shown). The vehicle drive device 103 is provided with a clutch portion 104 for transmitting and interrupting driving force. The clutch portion 104 is provided on the R1 side of the cylindrical portion 40 (described later) of the rotor 100 . The clutch portion 104 includes a first clutch portion 104a provided on the Z2 side and a second clutch portion 104b provided on the Z1 side of the cylindrical portion 40 of the rotor 100 on the R1 side.

Rotor 100 includes rotor core 10 , end plate 21 , end plate 22 , and rotor hub 30 . The rotor hub 30 is an example of a "rotor core supporting member" in the claims.

A rotor hub insertion hole 11 extending in the Z direction (axial direction) is formed in the rotor core 10 . As shown in FIG. 2, the rotor hub insertion hole 11 is provided in the central portion of the rotor core 10 when viewed in the Z direction. The rotor hub 30 is inserted into the rotor hub insertion hole 11 . That is, the rotor hub 30 is provided on the R1 side of the rotor core 10 . As will be described later, the rotor hub 30 is fixed to the rotor core 10 .

As shown in FIG. 1, the rotor core 10 is formed by laminating a plurality of electromagnetic steel sheets. The rotor core 10 is formed with a magnet insertion hole 12 extending in the stacking direction (Z direction) of the electromagnetic steel sheets. The magnet insertion hole 12 is arranged in a portion of the rotor core 10 on the R2 side. As shown in FIG. 2 , a plurality of (32 in this embodiment) magnet insertion holes 12 are provided in the rotor core 10 . The plurality of magnet insertion holes 12 are arranged at equal angular intervals along the C direction when viewed in the Z direction.

A permanent magnet 13 is accommodated (arranged) in each of the plurality of magnet insertion holes 12 . That is, the rotary electric machine 102 is configured as an interior permanent magnet motor (IPM motor). The permanent magnet 13 has a rectangular cross section perpendicular to the Z direction. The permanent magnet 13 is configured, for example, such that its magnetization direction (magnetization direction) is the transverse direction.

In the rotor core 10, magnetic poles 14 are formed by a pair of permanent magnets 13 adjacent in the C direction. That is, a plurality of (16 in this embodiment) magnetic poles 14 are formed in the rotor core 10 . A pair of permanent magnets 13 that form the magnetic pole 14 are arranged in a V shape protruding toward the R1 side. The shape of the pair of permanent magnets 13 forming the magnetic poles 14 is not limited to this.

The rotor core 10 includes a key portion 15 that protrudes from the inner peripheral surface of the rotor core 10 to the R1 side (radially inward). The key portion 15 has a rectangular shape when viewed in the Z direction. Two key portions 15 are provided in the rotor core 10 . The two key portions 15 are arranged at equal angular intervals (180 degrees) along the C direction when viewed in the Z direction. As shown in FIG. 3, the key portion 15 is provided at a position corresponding to the d-axis of the rotor core 10 in the C direction (circumferential direction). The key portion 15 is provided over the entire Z direction of the rotor core 10 .

As shown in FIG. 1, the end plate 21 is provided on the Z1 side of the rotor core 10 so as to abut on the end surface 10a of the rotor core 10 on the Z1 side. The end plate 22 is provided on the Z2 side of the rotor core 10 so as to abut on the end surface 10b of the rotor core 10 on the Z2 side. End plate 21 and end plate 22 are provided to prevent permanent magnet 13 from protruding from magnet insertion hole 12 .

Rotor hub 30 includes a cylindrical portion 40 and a flange portion 50 . As shown in FIG. 2, the cylindrical portion 40 has a cylindrical shape. Cylindrical portion 40 is provided on the R1 side of rotor core 10 such that the inner peripheral surface of rotor core 10 and the outer peripheral surface of cylindrical portion 40 face each other. The cylindrical portion 40 supports the rotor core 10 on the R1 side (radial inner side) of the rotor core 10 . As shown in FIG. 1, the flange portion 50 is joined to the end portion 41 of the cylindrical portion 40 on the Z1 side. The flange portion 50 is provided on the R1 side of the cylindrical portion 40 . A cylindrical portion side portion 51 of the flange portion 50 provided on the cylindrical portion 40 side (R2 side) extends from a joint portion 51a joined to the Z1 side end portion 41 of the cylindrical portion 40 toward the R1 side.

Cylindrical portion 40 includes a keyway portion 42 that engages key portion 15 . The key groove portion 42 is provided at a position facing the key portion 15 on the outer peripheral surface of the cylindrical portion 40 so as to be recessed toward the R1 side (inward in the radial direction). The key groove portion 42 is recessed in a rectangular shape toward the R1 side so as to engage with the rectangular key portion 15 projecting toward the R1 side. Two key groove portions 42 are provided in the cylindrical portion 40 . The two key groove portions 42 are arranged at equal angular intervals (180 degrees) along the C direction when viewed in the Z direction. As shown in FIG. 3, the key groove portion 42 is provided at a position corresponding to the d-axis of the rotor core 10 in the C direction. The key groove portion 42 is provided over the entire Z direction of the cylindrical portion 40 .

The rotor core 10 includes a relief portion 16 that is recessed toward the R2 side (radially outward) at a position adjacent to the key portion 15 in the C direction (circumferential direction). Specifically, the relief portions 16 are provided on both sides of the key portion 15 so as to be adjacent to the key portion 15 in the C direction. The relief portion 16 is provided to prevent the R2-side corner portion of the key groove portion 42 that engages with the key portion 15 from coming into contact with the base of the key portion 15 .

As shown in FIG. 2, the cylindrical portion 40 includes a plurality of spline recesses 43 recessed toward the R2 side (radially outward) so as to engage with the clutch portion 104 (see FIG. 1). Specifically, the clutch portion 104 includes a plurality of spline protrusions (not shown) projecting toward the R2 side at positions facing the plurality of spline recesses 43 of the cylindrical portion 40 on the outer peripheral surface of the clutch portion 104 . Each of the plurality of spline recesses 43 of the cylindrical portion 40 is engaged with the plurality of spline projections of the clutch portion 104 . The plurality of spline recesses 43 are provided over the entire cylindrical portion 40 in the Z direction (axial direction).

In addition, the key groove portion 42 is arranged between a plurality of spline recess portions 43 adjacent to each other in the C direction (circumferential direction). Specifically, as shown in FIG. 3, each of the plurality of spline recesses 43 is provided at a position corresponding to the q-axis of the rotor core 10 in the C direction. Further, as described above, the key groove portion 42 is provided at a position corresponding to the d-axis of the rotor core 10 in the C direction.

As a result, a key groove portion 42 provided so as to be recessed toward the R1 side (radially inward) in the cylindrical portion 40 and a plurality of spline recesses 43 provided so as to be recessed toward the R2 side (radial direction outward) in the cylindrical portion 40. However, it becomes difficult to overlap in the R direction (radial direction). As a result, the portion where the thickness in the R direction of the cylindrical portion 40 becomes excessively small (the strength is lowered) due to the overlapping of the key groove portion 42 and the plurality of spline recesses 43 in the R direction is wide in the C direction. can be prevented from occurring.

In addition, each of the plurality of spline recesses 43 includes a bottom surface portion 43a extending along the C direction (circumferential direction) and inclined side surface portions 43b that are continuous with the bottom surface portion 43a at both ends of the bottom surface portion 43a in the C direction. Specifically, in the plurality of spline recesses 43, the inclined side surface portion 43b, the bottom surface portion 43a, and the inclined side surface portion 43b are arranged in this order in the C direction. In addition, the inclined side surface portion 43b is inclined so that the width in the C direction (circumferential direction) increases toward the R1 side (diameter direction inner side). That is, each of the plurality of spline protrusions of the clutch portion 104 that engage with each of the plurality of spline recesses 43 has a width in the C direction that increases toward the R1 side. An end portion 42a of the key groove portion 42 in the C direction (circumferential direction) is provided at a position overlapping the inclined side surface portion 43b in the R direction (radial direction) in the C direction. Specifically, the end portion 42a of the key groove portion 42 in the C direction overlaps the central portion of the inclined side surface portion 43b in the R direction (radial direction) in the C direction.

As a result, the inclined side surface portion 43b, which is the end portion on the key groove portion 42 side in the C direction (circumferential direction) of the spline recess portion 43, overlaps the key groove portion 42 in the R direction (radial direction). That is, the key groove portion 42 and the spline recess portion 43 slightly overlap in the R direction. Further, since the bottom surface portion 43a is inclined so that the width in the C direction increases toward the R1 side (radially inward), even if the key groove portion 42 and the spline recessed portion 43 slightly overlap in the R direction, , a constant gap is formed between the key groove portion 42 and the spline recess portion 43 . As a result, the key groove portion 42 and the plurality of spline recesses 43 overlap in the R direction (radial direction), which causes the thickness of the cylindrical portion 40 in the R direction (radial direction) to become excessively small (strength is reduced). The width of the spline concave portion 43 in the C direction can be made relatively large while preventing the occurrence of a wide area in the C direction. Since the thickness of the spline recesses 43 in the C direction is relatively large, by engaging the clutch portion 104 (see FIG. 1) with the plurality of spline recesses 43 of the cylindrical portion 40 over a relatively wide range in the C direction, Torque can be efficiently transmitted between the cylindrical portion 40 (flange portion 50 ) and the clutch portion 104 .

(Fixation structure between rotor core and cylindrical portion)
Here, the rotor core 10 includes a clearance fitting portion 17 in which the cylindrical portion 40 is loosely fitted in the vicinity of the key portion 15 in the C direction (circumferential direction) of the rotor core 10 . That is, in the vicinity of the key portion 15 in the C direction (circumferential direction), there is a gap in the R direction between the clearance fitting portion 17 of the rotor core 10 and the portion of the cylindrical portion 40 facing the clearance fitting portion 17. always formed. In addition, the gap of the loose fit is, for example, several hundred micrometers to several meters.

As a result, when the cylindrical portion 40 is fitted into the rotor core 10, the clearance fitting portion 17 of the rotor core 10 and the clearance fitting portion 17 of the cylindrical portion 40 face each other in the vicinity of the key portion 15 in the C direction (circumferential direction). Since a gap in the R direction (radial direction) is formed between the portion where the rotor core 10 is located, the portion facing the clearance fitting portion 17 of the cylindrical portion 40 has a gap from the rotor core 10 toward the R1 side (radially inward). No external force is applied. As a result, when the cylindrical portion 40 is fitted into the rotor core 10, the stress generated in the portion of the cylindrical portion 40 near the key groove portion 42 facing the portion near the key portion 15 provided with the clearance fit portion 17 is reduced. can be reduced (effect 1). The effect of this stress reduction has already been confirmed by a simulation conducted by the inventor of the present application.

Further, the rotor core 10 includes an interference fit portion 18 in which the cylindrical portion 40 is tightly fit except in the vicinity of the key portion 15 in the C direction (circumferential direction). That is, in the interference fit portion provided outside the vicinity of the key portion 15 in the C direction, the portion of the cylindrical portion 40 that faces the interference fit portion 18 is tightened in the R direction by the interference fit portion 18 of the rotor core 10. It is As a result, the cylindrical portion 40 of the rotor hub 30 can be fixed to the R1 side (radially inward) of the rotor core 10 by the interference fit portion 18 except for the vicinity of the key portion 15 (Effect 2).

As a result of the effects 1 and 2, when the cylindrical portion 40 of the rotor hub 30 is fixed to the R1 side of the rotor core 10 by interference fit, the stress generated in the portion of the cylindrical portion 40 near the key groove portion 42 is reduced. can be done.

Further, the clearance fitting portion 17 is provided so as to be adjacent to the relief portion 16 on the side opposite to the key portion 15 in the C direction (circumferential direction). Specifically, in the rotor core 10, the key portion 15, the relief portion 16, and the clearance fitting portion 17 are arranged in this order in the C direction. The relief portion 16 is provided over the entire Z direction of the rotor core 10 .

As a result, when the cylindrical portion 40 is fitted into the rotor core 10 , the relief portion of the rotor core 10 is added between the clearance fitting portion 17 of the rotor core 10 and the portion of the cylindrical portion 40 facing the clearance fitting portion 17 . A gap in the R direction (radial direction) is also formed between 16 and a portion of the cylindrical portion 40 that faces the relief portion 16 . As a result, when the cylindrical portion 40 is fitted into the rotor core 10 , in addition to the portion of the cylindrical portion 40 facing the clearance fitting portion 17 , the portion of the cylindrical portion 40 facing the relief portion 16 is also provided with the rotor core. No external force is applied from 10 toward the R1 side (radially inward). As a result, the stress generated in the vicinity of the key groove portion 42 can be further reduced compared to the case where the escape portion 16 is not provided at the position adjacent to the key portion 15 in the C direction.

The rotor core 10 is adjacent to the clearance fitting portion 17 on the side opposite to the relief portion 16 in the C direction (circumferential direction) and is recessed toward the R2 side (radially outward). includes a coolant channel recess 19 through which the Specifically, in the rotor core 10, the key portion 15, the relief portion 16, the clearance fitting portion 17, and the coolant channel recess portion 19 are arranged in this order in the C direction. The coolant channel recesses 19 are provided over the entire Z direction of the rotor core 10 .

As a result, when the cylindrical portion 40 is fitted into the rotor core 10 , the space between the clearance fitting portion 17 of the rotor core 10 and the portion of the cylindrical portion 40 facing the clearance fitting portion 17 , and the relief portion 16 of the rotor core 10 . and the portion of the cylindrical portion 40 that faces the relief portion 16, the recessed portion 19 for the coolant flow path of the rotor core 10, and the portion of the cylindrical portion 40 that faces the recessed portion 19 for the coolant flow channel. A gap in the R direction (radial direction) is also formed between . Accordingly, when the cylindrical portion 40 is fitted into the rotor core 10, in addition to the portion of the cylindrical portion 40 facing the clearance fitting portion 17 and the portion of the cylindrical portion 40 facing the relief portion 16, the cylindrical portion An external force directed from the rotor core 10 toward the R1 side (radially inward) is not applied to the portion of the portion 40 that faces the coolant channel recess 19 . As a result, the stress generated in the vicinity of the key groove portion 42 is less than that in the case where the coolant passage recess portion 19 is not provided at a position adjacent to the clearance fitting portion 17 on the side opposite to the relief portion 16 in the C direction. can be further reduced.

Further, the clearance fitting portions 17 are provided near both sides of the key portion 15 in the C direction (circumferential direction). Specifically, in the rotor core 10 , the coolant passage recess 19 , the clearance fitting portion 17 , the relief portion 16 , the key portion 15 , the relief portion 16 , the clearance fitting portion 17 , and the coolant passage recess 19 are arranged in the C direction in this order. Note that the clearance fitting portion 17, the relief portion 16, and the coolant channel recess portion 19 provided on one side of the key portion 15 in the C direction, and the gap provided on the other side of the key portion 15 in the C direction. The fitting portion 17, the relief portion 16, and the coolant passage recess 19 are provided symmetrically with respect to the central position (d-axis) of the key portion 15 in the C direction.

As a result, when the cylindrical portion 40 is fitted to the rotor core 10 , the clearance fitting portion 17 of the rotor core 10 and the portion of the cylindrical portion 40 facing the clearance fitting portion 17 are formed in the vicinity of both sides of the key portion 15 . A gap in the R direction (radial direction) is formed between the . As a result, compared to the case where the clearance fitting portion 17 is provided only in the vicinity of one side of the key portion 15 in the C direction (circumferential direction), the gap is formed in the portion of the cylindrical portion 40 in the vicinity of the key groove portion 42 . Stress can be further reduced.

Further, the clearance fitting portion 17 is provided on the d-axis side of the q-axis of the rotor core 10 adjacent to the d-axis on which the key portion 15 is provided in the C direction (circumferential direction). Specifically, the coolant channel recess 19 is provided at a position corresponding to the q-axis of the rotor core 10 in the C direction. In the C direction, the clearance fitting portion 17 is provided closer to the key portion 15 provided at the position corresponding to the d-axis than the coolant passage recess 19 provided at the position corresponding to the q-axis. Thereby, the distance in the C direction (circumferential direction) between the clearance fitting portion 17 and the key portion 15 is made smaller than the distance between the d-axis and the q-axis that are adjacent to each other in the C direction (circumferential direction). Therefore, the clearance fitting portion 17 can be easily arranged in the vicinity of the key portion 15 in the C direction.

Further, the clearance fitting portion 17 is positioned so as to overlap in the R direction (radial direction) the portion of the spline recessed portion 43 adjacent to the key groove portion 42 in the C direction (circumferential direction) on the key groove portion 42 side. is provided. Specifically, the clearance fitting portion 17 is provided at a position overlapping the portion of the bottom surface portion 43a on the side of the inclined side surface portion 43b in the R direction (radial direction). As a result, the clearance fit portion 17 can be provided at a position where it overlaps a portion relatively close to the key groove portion 42 in the R direction (radial direction) in the C direction (circumferential direction). , C direction, it can be easily arranged in the vicinity of the key portion 15 .

[Manufacturing method of rotor]
A method of manufacturing the rotor 100 according to one embodiment will be described with reference to FIG.

First, in step S1, a preparatory step of preparing the rotor core 10 and the rotor hub 30 is performed. Specifically, in the preparation step (S1), the rotor core 10 including the key portion 15 projecting to the R1 side is prepared. Further, a rotor hub 30 having a cylindrical portion 40 including a key groove portion 42 that engages with the key portion 15 recessed toward the R1 side at a position facing the key portion 15 is prepared. Key portion 15 and key groove portion 42 are formed in rotor core 10 and cylindrical portion 40, respectively, by cutting, for example.

Next, in step S2, a fitting step of fitting the cylindrical portion 40 of the rotor hub 30 to the rotor core 10 is performed. Specifically, in the fitting step ( S<b>2 ), the cylindrical portion 40 of the rotor hub 30 is inserted (fitted) into the rotor hub insertion hole 11 extending in the Z direction of the rotor core 10 .

Here, the fitting step (S2) is a step of loose fitting in the vicinity of the key portion 15 in the C direction (circumferential direction) of the rotor core 10 . Specifically, in the preparation step (S1), the inner diameter of the portion (clearance fitting portion 17) of the rotor core 10 near the key portion 15 in the direction C to be clearance-fitted is adjusted to the clearance-fitting portion of the cylindrical portion 40. A rotor core 10 and a rotor hub 30 are prepared, which are larger than the external shape of the portion facing the one facing the rotor core 10 . Then, in the fitting step (S2), in the vicinity of the key portion 15 in the direction C, the portion of the rotor core 10 to be loosely fitted (the clearance fitting portion 17) and the portion of the cylindrical portion 40 facing the portion to be loosely fitted. A gap in the R direction is always formed between .

As a result, in the fitting step (S2), in the vicinity of the key portion 15 in the C direction (circumferential direction), the portion of the rotor core 10 to be loosely fitted (the clearance fitting portion 17) and the clearance between the rotor core 10 of the cylindrical portion 40 is formed. Since a clearance in the R direction (radial direction) is formed between the fitted portion and the opposed portion, the portion of the cylindrical portion 40 opposed to the clearance fitted portion has R1 from the rotor core 10 . No external force directed toward the side (inward in the radial direction) is applied. As a result, when the cylindrical portion 40 is fitted into the rotor core 10, the stress generated in the portion of the cylindrical portion 40 near the key groove portion 42 that faces the portion near the key portion 15 that is loosely fitted can be reduced. Yes (Effect 1).

Further, the fitting step (S2) is a step of performing interference fitting in areas other than the vicinity of the key portion 15 in the C direction (circumferential direction). Specifically, in the preparation step (S1), the inner diameter of the portion (interference fit portion 18) of the rotor core 10 other than the vicinity of the key portion 15 in the direction C to which the interference fit is performed is equal to the interference fit portion of the cylindrical portion 40. A rotor core 10 and a rotor hub 30, which are smaller than the outer shape of the portion facing the part to be welded, are prepared. Then, in the fitting step (S2), the inner diameter of the rotor core 10 is temporarily increased by heat expansion of the rotor core 10 by shrink fitting, for example, so that the cylindrical portion of the rotor hub 30 is inserted into the rotor hub insertion hole 11 extending in the Z direction of the rotor core 10. 40 is inserted. Due to the cooling shrinkage of the rotor core 10, the portion of the cylindrical portion 40 that faces the portion (interference fit portion 18) to which the interference fit is performed is the portion of the rotor core 10 other than the vicinity of the key portion 15 in the C direction. It is tightened to the part where

As a result, in the fitting step (S2), the cylindrical portion 40 of the rotor hub 30 can be fixed to the R1 side (diameter direction inner side) of the rotor core 10 by interference fitting at a portion other than the vicinity of the key portion 15 (Effect 2).

As a result of the effects 1 and 2, when the cylindrical portion 40 of the rotor hub 30 is fixed to the R1 side of the rotor core 10 by interference fit, the stress generated in the portion of the cylindrical portion 40 near the key groove portion 42 is reduced. can be done.

[Modification]
It should be noted that the embodiments disclosed this time should be considered as examples and not restrictive in all respects. The scope of the present invention is indicated by the scope of the claims rather than the description of the above-described embodiments, and includes all modifications (modifications) within the meaning and scope equivalent to the scope of the claims.

For example, in the above-described embodiment, the clearance fitting portion 17 is provided at a position overlapping the portion of the bottom surface portion 43a on the side of the inclined side surface portion 43b in the R direction (radial direction). It is not limited to this. In the present invention, the clearance fitting portion may be provided at a position that does not radially overlap the portion of the bottom portion on the inclined side surface portion side.

In the above-described embodiment, the end portion 42a of the key groove portion 42 in the C direction (circumferential direction) is provided at a position overlapping the inclined side surface portion 43b in the R direction (radial direction) in the C direction (circumferential direction). Although an example is shown, the present invention is not limited to this. In the present invention, the circumferential end portion of the key groove portion may be provided at a position that does not radially overlap the inclined side surface portion in the circumferential direction.

In the above embodiment, each of the plurality of spline recesses 43 includes an inclined side surface portion 43b that is inclined so that the width in the C direction (circumferential direction) increases toward the R1 side (radially inward). However, the present invention is not limited to this. In the present invention, each of the plurality of spline recesses may be configured to include a side surface portion whose width in the circumferential direction does not increase as it goes radially inward.

In the above embodiment, the clearance fitting portion 17 is provided closer to the d-axis than the q-axis of the rotor core 10 adjacent to the d-axis on which the key portion 15 is provided in the C direction (circumferential direction). Although shown, the invention is not so limited. In the present invention, the clearance fitting portion may be provided on the side opposite to the d-axis in the circumferential direction with respect to the q-axis of the rotor core adjacent to the d-axis on which the key portion is provided.

Further, in the above-described embodiment, the key portion 15 is provided at a position corresponding to the d-axis of the rotor core 10 in the C direction (circumferential direction), but the present invention is not limited to this. In the present invention, the key portion may be provided at a position that does not correspond to the d-axis of the rotor core in the circumferential direction.

Further, in the above-described embodiment, an example in which the clearance fitting portions 17 are provided in the vicinity of both sides of the key portion 15 in the C direction (circumferential direction) was shown, but the present invention is not limited to this. In the present invention, the clearance fitting portion may be provided only in the vicinity of one side of the key portion in the circumferential direction.

Further, in the above-described embodiment, the clearance fitting portion 17 is arranged in the R direction (radial direction) with the key groove portion 42 side portion of the spline recessed portion 43 provided so as to be adjacent to the key groove portion 42 in the C direction (circumferential direction). Although the example provided in the overlapping position was shown, this invention is not limited to this. In the present invention, the clearance fitting portion may be provided at a position that does not radially overlap the key groove portion side portion of the spline recess portion provided so as to be adjacent to the key groove portion in the circumferential direction.

Further, in the above-described embodiment, an example in which the key groove portion 42 is arranged between a plurality of mutually adjacent spline recess portions 43 in the C direction (circumferential direction) was shown, but the present invention is not limited to this. . In the present invention, the key groove portion may be arranged at a position other than between the plurality of spline recesses adjacent to each other in the circumferential direction.

In the above embodiment, the cylindrical portion 40 includes a plurality of spline recesses 43 recessed toward the R2 side (radially outward) so as to engage with the clutch portion 104, but the present invention is not limited to this. do not have. In the present invention, the cylindrical portion may be configured so as not to include a plurality of spline recesses recessed radially outward to engage with the clutch portion.

Further, in the above-described embodiment, the rotor core 10 is adjacent to the clearance fitting portion 17 on the side opposite to the relief portion 16 in the C direction (circumferential direction) and is recessed toward the R2 side (radially outward). Although the example including the coolant channel recess 19 through which the cooling coolant to be cooled flows has been shown, the present invention is not limited to this. In the present invention, the rotor core is configured so as not to include the coolant channel recess through which the cooling coolant for cooling the rotor core flows, which is provided so as to be adjacent to the clearance fit portion on the opposite side of the relief portion in the circumferential direction. may be

Further, in the above-described embodiment, an example in which the clearance fitting portion 17 is provided adjacent to the escape portion 16 on the opposite side of the key portion 15 in the C direction (circumferential direction) was shown, but the present invention is similar to this. is not limited to In the present invention, the clearance fitting portion may be provided on the opposite side of the key portion in the circumferential direction so as to be spaced apart from the relief portion.

In the above embodiment, the rotor core 10 includes the relief portion 16 provided so as to be recessed toward the R2 side (outside in the radial direction) at a position adjacent to the key portion 15 in the C direction (circumferential direction). , the present invention is not limited to this. In the present invention, the rotor core may be configured so as not to include the relief portion provided so as to be recessed radially outward at a position adjacent to the key portion in the circumferential direction.

Further, in the above-described embodiment, an example is shown in which the clutch portion 104 is applied to the rotor hub 30 provided on the R1 side (radial direction inner side) of the cylindrical portion as the "rotor core support member" in the scope of claims. The present invention is not limited to this. In the present invention, the "rotor core support member" in the claims may be applied to a rotor shaft having no clutch portion provided radially inward.

Further, in the above-described embodiment, an example in which two key portions 15 and two key groove portions 42 are provided in each of the rotor core 10 and the cylindrical portion 40 was shown, but the present invention is not limited to this. In the present invention, one key portion and one key groove portion may be provided in each of the rotor core and the cylindrical portion, or three or more thereof may be provided.

Further, in the above-described embodiment, the key portion 15 and the key groove portion 42 are provided over the entire Z direction (axial direction) of the rotor core 10 and the cylindrical portion 40, respectively. is not limited to In the present invention, the key portion may be provided only partially in the axial direction of the rotor core, and the key groove portion may be provided only partially in the axial direction of the cylindrical portion.

DESCRIPTION OF SYMBOLS 10... Rotor core 15... Key part 16... Relief part 17... Gap fitting part 18... Interference fitting part 19... Refrigerant channel recessed part 30... Rotor hub (rotor core support member) 40... Cylindrical part 41... Keyway portion 42 Spline concave portion 100 Rotor 104 Clutch portion

Claims (5)

a rotor core;
a rotor core support member including a cylindrical portion that supports the rotor core radially inside the rotor core;
The rotor core includes a key portion protruding radially inward,
the cylindrical portion includes a key groove portion that is recessed inward in the radial direction at a position facing the key portion and that engages with the key portion;
The rotor core has a clearance fitting portion in which the cylindrical portion is loosely fitted in the vicinity of the key portion in the circumferential direction of the rotor core, and the cylindrical portion is tightly fitted in portions other than the vicinity of the key portion in the circumferential direction. and an interference fit. The rotor core further includes a relief portion recessed radially outward at a position adjacent to the key portion in the circumferential direction,
2. The rotor according to claim 1, wherein said clearance fitting portion is provided so as to be adjacent to said relief portion on the opposite side of said key portion in said circumferential direction. The rotor core is adjacent to the clearance fitting portion on the opposite side of the relief portion in the circumferential direction and is recessed radially outward, through which a cooling coolant for cooling the rotor core flows. 3. The rotor of claim 2, further comprising: the cylindrical portion further includes a plurality of spline recesses recessed radially outward so as to engage with a clutch portion provided radially inwardly of the cylindrical portion;
The key groove portion is arranged between the plurality of spline recesses adjacent to each other in the circumferential direction,
The clearance fitting portion is provided at a position that radially overlaps with a portion of the spline recess that is adjacent to the key groove in the circumferential direction and is located on the side of the key groove. 4. The rotor according to any one of 3. A rotor manufacturing method comprising a rotor core and a rotor core support member including a cylindrical portion that supports the rotor core radially inside the rotor core,
Fitting for fitting the cylindrical portion including a key groove portion that is provided at a position facing the key portion so as to be recessed radially inward and engages with the key portion to the rotor core including the key portion that protrudes radially inward. Equipped with a process,
The fitting step is a step of performing clearance fitting in the vicinity of the key portion in the circumferential direction of the rotor core, and performing interference fitting in areas other than the vicinity of the key portion in the circumferential direction.

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