JP2017221024A - Rotor and rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor that is able to improve positional accuracy in mounting a permanent magnet on a rotor, and to provide a rotary electric machine.SOLUTION: In a circumferential direction of a rotor core 51, a permanent magnet 55 is sandwiched between a positioning projection 53 and a first leg part 57b of a first hold member. In the circumferential direction of the rotor core 51, the respective side faces of both ends of the permanent magnet 55 abut on the face 53c of a second projection 53a of the positioning projection 53 and on a face 57g of a first projection 57d of the first leg part 57b. In an axial direction of the rotor core 51, an inner face 55a of a permanent magnet 55 abuts on an abutting face 52a of the rotor core 51. In the axial direction of the rotor core 51, a first claw part 57f and a second claw part 53b abut on an external face 55b of the permanent magnet 55. A second leg part 58b of a second hold member abuts on a first groove 57e of the first leg part 57b with no gap between them.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a rotor and a rotating electrical machine.

  Conventionally, as described in Patent Document 1, there is provided a rotating electrical machine in which a plurality of salient poles having claw portions are provided along the circumferential direction on the outer circumferential surface of a rotor, and permanent magnets are inserted between adjacent salient poles. Are known. A resin material that is irreversibly thermally expandable is provided between an inner peripheral surface of the permanent magnet and a seating surface formed between adjacent salient poles. The permanent magnet is pressed toward the outside in the radial direction of the rotor by heating and expanding the resin material. The permanent magnet is fixed to the rotor by being kept pressed against the claw portion.

JP 2001-169485 A

  However, in the case of the above configuration, the expansion amount of the resin material may change depending on the degree of heating of the resin material. For this reason, there exists a possibility that dispersion | variation may arise in the attachment position of the permanent magnet with respect to a rotor.

  The objective of this invention is providing the rotor and rotary electric machine which can improve the precision of the attachment position of the permanent magnet with respect to a rotor.

  The rotor capable of achieving the above object is a rotor core having a plurality of positioning projections provided integrally with the outer circumferential surface at equal intervals along the circumferential direction, and the outer circumferential surface of the rotor core, A holding projection attached to a portion between the positioning projections adjacent in the circumferential direction, and the positioning projections provided on the outer peripheral surface of the rotor core and adjacent to each other in the circumferential direction of the rotor core And a plurality of permanent magnets provided between the holding projections, and the permanent magnets are in contact with the positioning projections and the holding projections in the circumferential direction of the rotor core. And

  According to the above configuration, in the circumferential direction of the rotor, the permanent magnet is sandwiched between the positioning protrusion and the holding protrusion, and the permanent magnet is positioned with respect to the rotor. For this reason, the dispersion | variation in the attachment position with respect to the rotor of each permanent magnet in the circumferential direction of a rotor core can be suppressed. Moreover, the position shift of the permanent magnet in the circumferential direction of the rotor core can be suppressed. Therefore, the mounting position accuracy of the permanent magnet with respect to the rotor is improved.

  The holding projection has a first claw that contacts the radially outer surface of the permanent magnet, and the positioning projection is a second claw that contacts the radially outer surface of the permanent magnet. It is preferable to have.

  According to the above configuration, the first claw portion and the second claw portion are in contact with the outer surfaces of the both sides of the permanent magnet in the circumferential direction of the rotor core in the radial direction of the rotor core. For this reason, it is possible to suppress the permanent magnets from being scattered radially outward due to the centrifugal force generated when the rotor is rotated.

  On the outer peripheral surface of the rotor core, a core groove extending along the axial direction of the rotor core is provided between the positioning protrusions adjacent in the circumferential direction, and one of the rotor cores in the axial direction is provided. A first base that abuts the end surface of the first base, and a first protrusion having a plurality of first legs that are provided on the peripheral edge of the first base as the holding protrusion and extend along the axial direction of the rotor core. A plurality of first members extending along the axial direction of the rotor core, the second base portion being in contact with the other end surface in the axial direction of the rotor core, and a peripheral portion of the second base portion. And a second holding member having two legs. The first leg portion includes an insertion portion that is fitted into the core groove portion, and a protruding portion that protrudes radially outward of the rotor core from the core groove portion in a state where the insertion portion is fitted into the core groove portion, A groove portion that is provided on a side surface opposite to the insertion portion in the radial direction of the rotor core of the protrusion, and into which the second leg portion is fitted, and the permanent magnet includes the first base portion and It is preferable that the second base portion is sandwiched in the axial direction of the rotor core and that the projecting portion and the positioning projection are sandwiched in the circumferential direction of the rotor core.

  According to the above configuration, in the axial direction of the rotor core, the permanent magnet is sandwiched between the first base portion of the first holding member and the second base portion of the second holding member. In addition, the permanent magnet is disposed between the positioning protrusion and the protrusion that is a portion that protrudes radially outward of the rotor core from the opening of the core groove in the first leg in the circumferential direction of the rotor core. It is caught. For this reason, the dispersion | variation in the attachment position with respect to the rotor core of the permanent magnet in the axial direction of a rotor core and the dispersion | variation in the attachment position in the axial direction of a rotor core can be suppressed.

It is preferable that the second leg portion elastically presses the first leg portion toward a radially inner side of the rotor core.
When the second leg is inserted into the groove of the first leg, the second holding member can be fixed with respect to the first holding member, but the second leg is the first leg. By elastically pressing the second holding member, the second holding member can be more strongly fixed to the first holding member. Therefore, it is possible to further maintain a state in which the positional deviation in the axial direction of the rotor core with respect to the permanent magnets of the first base of the first holding member and the second base of the second holding member is suppressed. .

  A plurality of different phases, comprising: the rotor described above; and a stator having a plurality of teeth facing the outer peripheral surface of the rotor and a winding wound around the teeth in the radial direction of the rotor. On the other hand, a rotating electrical machine to which each of the plurality of windings corresponds is assumed. The rotor core including the positioning protrusion is a magnetic body, the holding member is a non-magnetic body, the winding facing the positioning protrusion in the radial direction of the rotor, and the radial direction of the rotor It is preferable that the winding facing the holding projection corresponds to the same phase, and the plurality of windings of the same phase including the winding are connected in series.

  When the rotor having the above configuration is applied to a rotating electrical machine, there are concerns about the following. The phase that faces the positioning protrusion in the radial direction of the rotor core and the phase that faces the holding protrusion in the radial direction of the rotor core may be the same phase. In that case, the positioning protrusion 53, which is a magnetic substance, acts as a magnetic resistance, and the surface magnetic flux density distribution in the vicinity of the winding of the phase facing the positioning protrusion in the radial direction of the rotor core is disturbed. Therefore, a phase difference may occur in the induced voltage generated in each winding of each phase.

  In that respect, in the above configuration, the windings of the same phase are connected in series. By synthesizing and averaging the induced voltage generated in each winding of each phase, the phase difference of the induced voltage generated in each winding of each phase can be eliminated. That is, the magnetically unstable state of windings of the same phase can be eliminated. Therefore, the rotor can be smoothly rotated.

  The rotating electrical machine may be a three-phase brushless motor.

  According to the rotor and the rotating electrical machine of the present invention, it is possible to improve the accuracy of the attachment position of the permanent magnet with respect to the rotor.

Sectional drawing cut | disconnected along the axial direction in one Embodiment of a rotary electric machine. Sectional drawing of the rotary electric machine in embodiment seen from the direction cut | disconnected along 2-2 line of FIG. (A) is a disassembled perspective view of the rotor in embodiment, (b) is a perspective view after the assembly | attachment of the rotor in embodiment is completed. Sectional drawing which showed the attachment state of the permanent magnet with respect to the rotor core in the rotor in embodiment. (A) is the star connection figure of the rotary electric machine in embodiment, (b) is the schematic block diagram which showed arrangement | positioning of each U-phase coil | winding connected in series in the rotary electric machine of embodiment. In the rotary electric machine of embodiment, the wave form diagram which showed the relationship between the electrical angle of the induced voltage induced by the U-phase coil | winding, and an induced voltage value. Sectional drawing in other embodiment of a rotary electric machine.

  Hereinafter, an embodiment in which the rotating electrical machine is embodied as an inner rotor type three-phase brushless motor will be described. The rotating electrical machine of this example is mounted on a vehicle, for example, and used as a drive source of an electric power steering device that assists steering operation.

  As shown in FIG. 1, the rotating electrical machine 10 includes a bottomed cylindrical case 20 and a lid 70 that closes an opening of the case 20. A cylindrical stator 30 is fixed to the inner peripheral surface of the case 20. The stator 30 includes a cylindrical stator core 31, two insulators 35 provided at both ends in the axial direction of the stator core 31, and a plurality of windings 36 wound around the stator core 31 via these insulators 35. .

The stator core 31 is configured by laminating a plurality of disc-shaped electromagnetic steel plates along the axial direction thereof.
The stator 30 is provided with a cylindrical rotor 50 with a gap in the radial direction. An output shaft 71 is fitted on the inner periphery of the rotor 50. The output shaft 71 passes through the rotor 50. Both end portions of the output shaft 71 are rotatably supported through two bearings 72 and 73 provided in the inner bottom portion of the case 20 and the inside of the lid 70, respectively.

The insulator 35 is made of an insulating resin material. The insulator 35 prevents the winding 36 from directly contacting the stator core 31.
A disc-shaped holder 80 made of resin is provided at an end of the stator 30 on the lid 70 side. The holder 80 holds a plurality of bus bars 81. Each bus bar 81 is connected to a winding 36 of each phase. Three-phase AC power is supplied to the windings 36 of each phase via the bus bars 81.

  As shown in FIG. 2, the stator core 31 is provided on a cylindrical portion 32 fixed to the inner peripheral surface of the case 20, and a plurality of (cores) are provided on the inner peripheral surface of the cylindrical portion 32 and extend radially inward in the radial direction. In the embodiment, twelve teeth 33 are provided. Extending portions 33 a that extend in opposite directions in the circumferential direction of the rotor 50 are formed at the radially inner ends of the teeth 33.

  A winding 36 is wound around each tooth 33 in a concentrated manner through an insulator 35. An insulating member 37 made of synthetic resin is interposed between the windings 36 adjacent to each other in the circumferential direction of the rotor 50. The insulation member 37 ensures insulation between the windings 36 adjacent in the circumferential direction of the rotor 50.

Next, a method for connecting the windings 36 in the rotating electrical machine 10 will be described.
As shown in FIG. 2, the rotating electrical machine 10 is a three-phase brushless motor having 10 poles, three phases, and 12 coils. Four windings 36 correspond to each phase (U phase, V phase, W phase). Here, the four windings 36 of each phase are distinguished by assigning numbers 1 to 4 to alphabets (U, V, W) indicating the respective phases. In the four windings 36 of each phase, the first winding 36 and the third winding 36 and the second winding 36 and the fourth winding 36 are provided at positions facing each other in the radial direction of the stator 30. It has been.

  As shown in FIG. 5A, the windings 36 of each phase are star-connected through the bus bars 81. The windings 36 of the same phase are connected in series. As an example, a method of connecting four U-phase windings 36 will be described.

  As shown in FIG. 5B, in the circumferential direction of the stator 30, the first ends of two adjacent windings 36 (U1, U2) are connected to each other. Similarly, the first ends of the two windings 36 (U3, U4) are connected to each other. Further, the second ends of U2 and U32 are connected to each other. The second ends of U1 and U4 are each connected to a three-phase AC power source. Similarly, the V-phase and W-phase windings 36 are connected in series.

Next, the configuration of the rotor 50 will be described.
As shown in FIG. 3A, the rotor 50 is composed of a rotor core 51, which is a magnetic body, a plurality of permanent magnets 55 (in this embodiment, five N poles and five S poles, a total of 10), a composite A first holding member 57 and a second holding member 58 made of resin are provided.

  The outer peripheral surface of the rotor core 51 is provided with the same number of contact surfaces 52a as the permanent magnets 55, thereby forming a polygonal pyramid shape. A permanent magnet 55 is disposed on the contact surface 52a. Further, on the outer peripheral surface of the rotor core 51, a core groove portion 54 and positioning protrusions that form two sets at a boundary portion (a total of ten locations) between two contact surfaces 52a adjacent to each other in the circumferential direction. 53 are alternately provided in the circumferential direction of the rotor core 51.

  The permanent magnet 55 has a rectangular plate shape. In the permanent magnet 55, an inner surface 55a that is a side surface in contact with the contact surface 52a of the rotor core 51 is a flat surface. An outer surface 55 b that is a side surface opposite to the inner surface 55 a of the permanent magnet 55 is a curved surface that curves along the circumferential direction of the rotor core 51. The thickness of the permanent magnet 55 gradually decreases from the central portion of the permanent magnet 55 in the circumferential direction of the rotor core 51 toward both end portions. The lengths of the permanent magnet 55 in the vertical direction (axial direction of the rotor core 51) and the horizontal direction (circumferential direction of the rotor core 51) are the same as the vertical and horizontal lengths of the contact surface 52a.

The core groove portion 54 extends over the entire length of the rotor core 51 in the axial direction.
The positioning protrusion 53 is provided integrally with the rotor core 51. The two positioning protrusions 53 of each set are arranged along the axial direction of the rotor core 51. The two positioning projections 53 of each set are provided so as to correspond to each of the two parts divided on the basis of the midpoint of the length in the axial direction of the permanent magnet 55 arranged on the contact surface 52a. ing.

  As shown in FIG. 4, the positioning protrusion 53 has a second protrusion 53a and two second claws 53b. The second projecting portion 53 a projects outward in the radial direction from a boundary portion between two contact surfaces 52 a adjacent to each other in the circumferential direction of the rotor core 51. In addition, the second protrusion 53 a has two surfaces 53 c that come into contact with the permanent magnet 55 disposed on the contact surface 52 a in the circumferential direction of the rotor core 51. The 2nd nail | claw part 53b is extended toward the mutually opposite side along the circumferential direction from the front-end | tip of the 2nd protrusion part 53a. These second claw portions 53b face the outer peripheral surface (more precisely, the contact surface 52a) of the rotor core 51 in the radial direction of the rotor core 51.

The first holding member 57 includes a disk-shaped first base portion 57a that faces the rotor core 51 in the axial direction, and the same number (five in this example) of first leg portions 57b as the core groove portions 54. Have.
The outer diameter of the first base 57 a is set to be equal to the outer diameter of the virtual cylinder including the tip of the positioning protrusion 53 in the radial direction of the rotor core 51.

  Each first leg portion 57b is provided on a side surface of the first base portion 57a on the rotor core 51 side. The first leg portions 57 b are provided at equal intervals in the circumferential direction of the first base portion 57 a of the first holding member 57. Each first leg portion 57 b corresponds to the position of each core groove portion 54 in the circumferential direction of the rotor core 51. Each first leg portion 57 b extends along the axial direction of the rotor core 51. The length of each first leg portion 57b in the axial direction of the rotor core 51 is equal to the length of the core groove portion 54 of the rotor core 51 in the axial direction.

As shown in FIG. 4, the first leg portion 57b has a first projecting portion 57d, an insertion portion 57c, and two first claw portions 57f.
The insertion portion 57c is a portion on the inner side of the first protrusion 57d in the radial direction of the first base portion 57a, and is also a portion fitted into the core groove portion 54. The insertion portion 57 c has an outer shape corresponding to the groove shape of the core groove portion 54. Due to the concavo-convex relationship between the insertion portion 57 c and the core groove portion 54, the insertion portion 57 c is prevented from coming off in the radial direction of the rotor core 51.

  The first projecting portion 57d is a portion extending from the opening portion of the core groove portion 54 toward the radially outer side of the rotor core 51 in a state where the insertion portion 57c is fitted in the core groove portion 54. The first projecting portion 57d has two surfaces 57g that contact the side surfaces of the permanent magnet 55 in the circumferential direction of the rotor core 51.

  A first groove 57e is provided on the outer circumferential surface of the first leg 57b (more precisely, the first protrusion 57d) in the radial direction of the rotor core 51. The 1st groove part 57e is provided over the full length in the axial direction of the rotor core 51 of the 1st leg part 57b. As viewed from the axial direction of the rotor core 51, the first holding member 57 has an arcuate curved surface.

  The two first claw portions 57f are opposite to each other along the circumferential direction of the rotor core 51 at the radially outer tip portion of the first leg portion 57b (more precisely, the first protruding portion 57d). Projecting towards. The two first claw portions 57f face the outer peripheral surface (more precisely, the contact surface 52a) of the rotor core 51 in the radial direction of the rotor core 51.

  As shown in FIG. 3A, the number of the second holding members 58 is equal to the number of the disk-shaped second base portions 58a facing the rotor core 51 in the axial direction and the first groove portions 57e (in this example, 5) second leg portions 58b.

The outer diameter of the second base 58 a is set to be equal to the outer diameter of the virtual cylinder including the tip of the positioning protrusion 53 in the radial direction of the rotor core 51.
Each second leg 58b is provided on the side surface of the second base 58a of the second holding member 58 on the rotor core 51 side. The second leg portions 58b are provided at equal intervals in the circumferential direction of the second base portion 58a. Each second leg portion 58 b corresponds to the position of each first groove portion 57 e in the circumferential direction of the rotor core 51. Each second leg portion 58 b extends along the axial direction of the rotor core 51. The length of each second leg portion 58b in the axial direction is equal to the length of the first groove portion 57e in the axial direction of the rotor core 51. When viewed from the axial direction of the rotor core 51, the shape of the second leg portion 58b is a semicircular shape that fits almost exactly into the first groove portion 57e, specifically, slightly enlarged with respect to the first groove portion 57e. It has a similar semicircular shape.

Next, a method for assembling the rotor 50 will be described.
The rotor 50 is assembled through a temporary magnetizing process, an assembling process, and a permanent magnetizing process on the permanent magnet 55.

In the temporary magnetization process, the inner surface 55a of the permanent magnet 55 before magnetization is magnetized to such an extent that a slight attractive force is exerted on the rotor core 51.
In the assembly process, the permanent magnet 55 is directed toward the positioning protrusion 53 in the circumferential direction of the rotor core 51 while the inner surface 55a of the permanent magnet 55 that has undergone the temporary magnetization process is brought into contact with the contact surface 52a of the rotor core 51. And is pushed between the second claw portion 53b of the positioning projection 53 and the contact surface 52a. Along with this, the side surface (right side surface in FIG. 4) of the permanent magnet 55 in the circumferential direction of the rotor core 51 abuts on the surface 53c of the second protrusion 53a, whereby the permanent magnet 55 is Are positioned in the circumferential direction. When the permanent magnet 55 is pushed between the second claw portion 53b and the contact surface 52a, the radially inner surface of the rotor core of the second claw portion 53b and the outer surface 55b of the permanent magnet 55 are mutually connected. Slide. The permanent magnet 55 (the right side surface in FIG. 4) is applied by the reaction force from the second claw portion 53b when the permanent magnet 55 is pushed between the second claw portion 53b and the contact surface 52a. It is pressed against the contact surface 52a.

  In the permanent magnet 55, the portion pushed between the second claw portion 53b and the contact surface 52a is held in a state of being sandwiched in the thickness direction by the second claw portion 53b and the contact surface 52a. . The inner surface 55a of the permanent magnet 55 is temporarily magnetized. For this reason, it is adsorbed by the contact surface 52a. For this reason, the positioning state of the permanent magnet 55 with respect to the rotor core 51 is maintained. Similarly, all the permanent magnets 55 are attached to the contact surfaces 52a in the above-described positioning state.

Next, the first holding member 57 is assembled to the rotor core 51.
In a state where the positions of the first leg portions 57b of the first holding member 57 are aligned with the core groove portions 54 of the rotor core 51, the first holding member 57 is placed on the rotor core 51 along the axial direction thereof. Close. Then, the first leg portion 57b of the first holding member 57 is gradually fitted into the core groove portion 54 while being guided from the tip end while sliding with respect to the core groove portion 54 of the rotor core 51. At this time, the first leg portion 57b slides against the permanent magnet 55 in such a manner as to push the two permanent magnets 55 adjacent in the circumferential direction of the rotor core 51 to the opposite sides. Eventually, the first base 57a of the first holding member 57 comes into contact with the rotor core 51 and the permanent magnet 55 in the axial direction. At this timing, the insertion of the insertion portion 57c into the core groove portion 54 is completed. When the insertion portion 57c is fitted into the core groove portion 54, the first claw portion 57f of the first leg portion 57b slides with respect to the outer surface 55b in the radial direction of the rotor core 51 of the permanent magnet 55, It is slightly elastically deformed in the direction away from the contact surface 52a. In a state where the insertion of the insertion portion 57 c into the core groove portion 54 is completed, the first claw portion 57 f is kept in contact with the outer surface 55 b of the permanent magnet 55. The permanent magnet 55 (left side in FIG. 4) is pressed against the contact surface 52a also by the elastic force of the first claw portion 57f. Further, in the circumferential direction of the rotor core 51, the permanent magnet 55 is kept pressed by the first projecting portion 57d toward the second projecting portion 53a.

  Thereafter, in the axial direction of the rotor core 51, the second holding member 58 is brought close to the rotor core 51 from the side opposite to the mounting direction of the first holding member 57. Then, the second leg portion 58b of the second holding member 58 is guided from the tip while sliding with respect to the first groove portion 57e of the first holding member 57, and thus the first groove portion 57e. Will gradually fit into. At this time, each second leg 58b is slightly elastically deformed inward in the radial direction of the second base 58a. Eventually, the second base portion 58a comes into contact with the rotor core 51, the first leg portion 57b of the first holding member 57, and the permanent magnet 55 in the axial direction. At this timing, the insertion of the second leg portion 58b into the first groove portion 57e is completed. In a state where the insertion of the second leg portion 58b into the first groove portion 57e is completed, the second leg portion 58b is kept in contact with the entire first groove portion 57e without a gap. Each first leg portion 57b is maintained in a state of being pressed inward in the radial direction of the rotor core 51 by the elastic force of each second leg portion 58b. Further, the radially outer surface of the rotor core 51 in the second leg portion 58 b is substantially the same as the radially outer surface of the rotor core 51 in the first leg portion 57 b of the first holding member 57. 1 (state without steps).

  As shown in FIG. 3B, finally, in the main magnetization process, the temporarily magnetized permanent magnet 55, the first holding member 57, and the second holding member 58 are attached to the rotor core 51. In the assembled state, the permanent magnet 55 is fully magnetized. Specifically, the outer surface 55 b of each permanent magnet 55 is magnetized so as to be alternately N and S poles in the circumferential direction of the rotor core 51. When the permanent magnet 55 is completely magnetized, the assembly of the rotor 50 is completed.

As described in detail above, according to the rotor 50 and the rotating electrical machine 10 according to the present embodiment, the following operations and effects can be obtained.
(1) When the rotor 50 is assembled, in the circumferential direction of the rotor 50, the permanent magnet 55 is located between the second protrusion 53a of the positioning protrusion 53 and the first protrusion 57d of the first leg 57b. Sandwiched between. For this reason, the dispersion | variation in the attachment position with respect to the rotor 50 of the permanent magnet 55 in the circumferential direction of the rotor core 51 can be suppressed. In addition, after the rotor 50 is assembled, the displacement of the permanent magnet 55 in the circumferential direction of the rotor core 51 is also suppressed. Therefore, the mounting position accuracy of the permanent magnet 55 with respect to the rotor 50 is improved.

  (2) When the rotor 50 is assembled, in the axial direction of the rotor core 51, the permanent magnet 55 includes the first base portion 57 a of the first holding member 57 and the second base portion 58 a of the second holding member 58. It is sandwiched between. For this reason, the dispersion | variation in the attachment position with respect to the rotor core 51 of the permanent magnet 55 in the axial direction of the rotor core 51 is suppressed. Moreover, the position shift in the axial direction of the rotor core 51 can also be suppressed after the rotor 50 is assembled.

  (3) Further, when the rotor 50 is assembled, the outer surfaces of both side portions of the permanent magnet 55 in the circumferential direction of the rotor core 51 are arranged on the rotor core 51 by the second claw portion 53b and the first claw portion 57f. Is pressed against the contact surface 52a. For this reason, the dispersion | variation in the attachment position with respect to the rotor core 51 of the permanent magnet 55 in the radial direction of the rotor core 51 is suppressed. Further, after the rotor 50 is assembled, the radial displacement of the permanent magnet 55 relative to the rotor 50 is suppressed. In addition, the permanent magnet 55 is prevented from being scattered radially outward by the centrifugal force generated when the rotor 50 rotates.

  (4) The second leg portion 58 b elastically presses the first leg portion 57 b toward the inner side in the radial direction of the rotor core 51 through the first groove portion 57 e. As indicated by an arrow F1 in FIG. 4, the force (elastic force) by which the second leg portion 58b pushes the first leg portion 57b inward in the radial direction of the rotor core 51 is the arc surface of the first groove portion 57e. It travels radially along the contour. This pressing force acts as a force (arrow F2 in FIG. 4) that presses the side surface of the permanent magnet 55 in the circumferential direction of the rotor core 51 via the first protrusion 57d. Thereby, the permanent magnet 55 is pressed more strongly toward the second protrusion 53 a of the positioning protrusion 53. That is, the permanent magnet 55 is more strongly fixed to the rotor core 51 in the circumferential direction of the rotor core 51. Similarly, the pressing force indicated by the arrow F1 is a force that presses the outer surface 55b of the permanent magnet 55 in the radial direction of the rotor core 51 via the first claw portion 57f (the arrow in FIG. 4). F3). Thereby, the permanent magnet 55 is pressed more strongly toward the contact surface 52 a of the rotor core 51. That is, the permanent magnet 55 is more strongly fixed to the rotor core 51 in the radial direction of the rotor core 51. Therefore, after the rotor 50 is assembled, positional deviation in the circumferential direction and the radial direction of the permanent magnet 55 with respect to the rotor 50 can be suppressed.

  (5) One set of the two positioning protrusions 53 of each set is provided in each of the parts divided with reference to the midpoint of the length of the permanent magnet 55 in the axial direction. For this reason, when the permanent magnet 55 is attached when the rotor 50 is assembled, the permanent magnet 55 can be prevented from rotating around the positioning projection 53.

  (6) When the rotor 50 is applied to the rotating electrical machine 10, the following may be a concern. That is, in the circumferential direction of the rotor core 51, the five positioning protrusions 53 provided integrally with the rotor core 51 that is a magnetic body and the first holding member 57 that is a nonmagnetic body Leg portions 57b are provided at equal intervals. Therefore, the positioning projection 53 and the first leg portion 57b of the first holding member 57 face each other in the radial direction of the rotor core 51. That is, the phase in which the positioning projection 53 faces in the radial direction of the rotor core 51 and the phase in which the first leg 57b of the first holding member 57 faces in the radial direction of the rotor core 51 are the same. Become a phase. For example, as shown in FIG. 2, between two windings 36 (for example, U1 and U3) of the same phase that are opposed to each other in the radial direction of the rotor core 51, a positioning protrusion 53 that is a magnetic body and The first leg portion 57b of the first holding member 57 that is a non-magnetic material is disposed. For this reason, the positioning protrusion 53, which is a magnetic body, acts as a magnetic resistance, and the phase winding 36 (U1 in FIG. 2) provided at a position facing the positioning protrusion 53 and the rotor core 51 in the radial direction. ) Disturbance occurs in the surface magnetic flux density distribution in the vicinity. Therefore, as shown in an example in the graph of FIG. 6, a phase difference occurs in the induced voltage generated in each of the U-phase windings 36 (U 1, U 2, U 3, U 4), thereby preventing smooth rotation of the rotor 50. There is a risk that. The same applies to the V phase and the W phase.

  In that respect, according to the present embodiment, the four windings 36 of the same phase are connected in series. As shown by the thick solid line in the graph of FIG. 6, by connecting the four windings 36 of each phase in series, an induced voltage having a phase difference generated in each of the four windings 36 of each phase is synthesized. The For this reason, the phase difference of the induced voltage which generate | occur | produces in each phase can be eliminated. Therefore, the rotor 50 can be smoothly rotated.

  (7) As a method of assembling the permanent magnet to the rotor, a method of pressing the permanent magnet between the plurality of salient poles provided on the outer peripheral surface of the rotor core is also conceivable. However, in the case of this method, when the magnet is attached, it is necessary to strictly manage the positions between the salient poles and the magnet in the circumferential direction of the rotor core. This is because the permanent magnet may come into contact with the salient pole in the axial direction of the rotor core.

  In this regard, according to the method of assembling the rotor 50 of this example, the permanent magnet 55 is slid in the circumferential direction of the rotor core 51 while the inner surface 55a of the permanent magnet 55 is in contact with the contact surface 52a of the rotor core 51. The side surface in the circumferential direction of 55 is pressed against the positioning projection 53. Thereby, the permanent magnet 55 is easily positioned in the circumferential direction of the rotor core 51. For this reason, when assembling the permanent magnet 55 to the rotor core 51, it is not necessary to strictly manage the position of the permanent magnet 55 with respect to the rotor core 51. Therefore, the manufacturing efficiency of the rotor 50 is improved.

Note that the present embodiment may be modified as follows within a technically consistent range.
-In this Embodiment, if the material of the 1st holding member 57 and the 2nd holding member 58 is a nonmagnetic material which can be elastically deformed, you may change suitably. For example, you may be comprised with metals, such as aluminum and stainless steel.

  In the present embodiment, the number of positioning protrusions 53 provided at the boundary between the two contact surfaces 52a and 52a adjacent in the circumferential direction of the rotor core 51 may be changed as appropriate according to product specifications. For example, one or more positioning protrusions 53 may be provided along the axial direction of the rotor core 51 at the boundary between the two contact surfaces 52a and 52a. By doing so, the permanent magnet can be positioned in the circumferential direction of the rotor core.

  In the present embodiment, the second leg portion 58b of the second holding member 58 is inserted over the entire length of the first groove portion 57e, but is not limited thereto. That is, when the second base portion 58a comes into contact with the axial surface of the rotor core 51, the second leg portion 58b does not have to come into contact with the first base portion 57a. Even in this case, the second holding member 58 can be attached to the first holding member 57.

  In addition, a configuration in which the second holding member 58 is omitted may be employed as the rotor 50. Even in that case, the permanent magnet 55 is held between the first leg portion 57 b of the first holding member 57 and the positioning protrusion 53. Further, in this case, a configuration in which the first base 57a is omitted may be employed as the first holding member 57. Also in this case, the permanent magnet 55 can be held with respect to the rotor 50 between the first leg 57 b and the positioning projection 53 in the first holding member 57.

  Further, as the configuration of the first holding member 57, a configuration in which the two first claw portions 57f and the two second claw portions 53b are omitted may be employed. Even in this case, the permanent magnet 55 is sandwiched between the second protrusion 53a of the positioning protrusion 53 and the first protrusion 57d of the first leg 57b. For this reason, friction arises between the side surface of the permanent magnet 55 in the circumferential direction of the rotor core 51, the surface 57g of the first protrusion 57d, and the surface 53c of the second protrusion 53a. That is, the positional deviation of the permanent magnet 55 in the circumferential direction and the axial direction of the rotor core 51 can be suppressed. Moreover, it is good also as a structure which omitted the 1st nail | claw part 57f or the 2nd nail | claw part 53b.

  In the present embodiment, the first groove 57e of the first holding member 57 is an arcuate groove, but is not limited thereto, and may be a rectangular groove, for example. However, the outer diameter shape of the second leg portion 58b of the second holding member 58 is provided in a quadrangular prism shape corresponding to the first groove portion 57e.

  In the present embodiment, a brushless motor having three phases, 10 poles and 12 slots has been described as an example, but the present invention is not limited to this. For example, as shown in FIG. 7, it may be a three-phase 16-pole 18-slot brushless motor. (Compared with the present embodiment, the number of permanent magnets 55 and the number of windings 36 increases by six. For the winding 36, the number of windings 36 increases by two for each phase. As a specific example, U5 is U5. The number of the windings 36 of U and U6 increases, and the same applies to the V phase and the W phase.) However, as the number of permanent magnets 55 and the number of windings 36 is changed, the positioning projection 53 and the contact surface 52a of the rotor core 51 are increased. In addition, the number of first leg portions 57b of the first holding member 57 is appropriately changed.

  As shown in FIG. 7, for example, when 16 permanent magnets are used, different magnetic poles (N pole and S pole) on both sides in the circumferential direction of the positioning projection 53 are the first holding members 57 in the circumferential direction. The permanent magnet 55 may be arranged so that the same magnetic pole (N pole or S pole) is located on both sides of the first leg portion 57b. In that case, in the circumferential direction of the rotor core 51, the magnetism of each permanent magnet 55 is alternately different by two. Moreover, as shown in FIG. 7, in the circumferential direction of the rotor core 51, the windings 36 of the same phase may be provided separately every 120 degrees. Also in this case, it is preferable to connect six windings 36 of the same phase in series. Similar to the present embodiment, in the radial direction of the rotor core 51, a positioning protrusion 53 that can be a magnetic resistance and a first leg 57b of the first holding member 57 are provided at positions where the same phase is opposed. Therefore, by connecting the six windings 36 of the same phase in series, the induced voltages generated in the windings 36 of the same phase are combined, thereby eliminating the phase difference.

Next, a technical idea that can be grasped from the above embodiment will be described.
(A) In the above configuration, the cross-sectional shape obtained by cutting the second leg portion in a direction orthogonal to the axial direction of the rotor core is such that the first groove portion is orthogonal to the axial direction of the rotor core. A similar shape slightly enlarged relative to the cut cross-sectional shape.

  According to the above configuration, the second leg portion elastically presses the first leg portion toward the radially inner side of the rotor core via the first groove portion. The force by which the second leg portion elastically presses the first leg portion radially inward of the rotor core is transmitted to the permanent magnet along the contour of the first groove portion. This pressing force acts as a force for pressing the side surface of the permanent magnet in the circumferential direction of the rotor core via the protrusion. Thereby, a permanent magnet is pressed more strongly toward a positioning protrusion. That is, the permanent magnet is more strongly fixed to the rotor core in the circumferential direction of the rotor core. In addition, a first claw portion that abuts the holding projection on the outer surface in the radial direction of the rotor core of the permanent magnet, and a first claw portion that abuts on the outer surface in the radial direction of the rotor core of the permanent magnet on the positioning projection. Suppose that it has two nail parts. At that time, the force by which the second leg presses the first leg also acts as a force pressing the outer surface of the permanent magnet in the radial direction of the rotor core via the first claw. Thereby, a permanent magnet is pressed more strongly toward the outer peripheral surface of a rotor core. That is, the permanent magnet is more strongly fixed to the rotor core in the radial direction of the rotor core. That is, the variation in the attachment position of the permanent magnet with respect to the rotor in the circumferential direction and the radial direction of the rotor core can be further suppressed. Moreover, the position shift of the permanent magnet in the circumferential direction of the rotor core can be suppressed.

DESCRIPTION OF SYMBOLS 10 ... Rotary electric machine, 30 ... Stator, 33 ... Teeth, 36 ... Winding, 50 ... Rotor, 51 ... Rotor core, 53 ... Positioning protrusion, 53a ... 2nd protrusion, 53b ... 2nd nail | claw part 54 ... Core groove part, 55 ... Permanent magnet, 57 ... First holding member, 57a ... First base part, 57b ... First leg part, 57c ... Insertion part, 57d ... First protrusion part, 57e ... First 1 groove part, 57f ... 1st nail | claw part, 58 ... 2nd holding member, 58a ... 2nd base part, 58b ... 2nd leg part.

Claims (6)

A rotor core having a plurality of positioning protrusions provided at equal intervals along the circumferential direction on the outer peripheral surface; and
On the outer peripheral surface of the rotor core, a holding protrusion attached to a portion between the positioning protrusions adjacent in the circumferential direction;
A permanent magnet provided on the outer peripheral surface of the rotor core and provided between the positioning protrusion and the holding protrusion adjacent to each other in the circumferential direction of the rotor core;
The permanent magnet is a rotor in contact with the positioning protrusion and the holding protrusion in the circumferential direction of the rotor core. The holding projection has a first claw portion that comes into contact with a radially outer surface of the permanent magnet,
The rotor according to claim 1, wherein the positioning protrusion has a second claw portion that comes into contact with a radially outer surface of the permanent magnet. On the outer peripheral surface of the rotor core, a core groove portion extending along the axial direction of the rotor core is provided between the positioning protrusions adjacent in the circumferential direction,
A first base that abuts one end surface in the axial direction of the rotor core, and a plurality of protrusions that are provided on the peripheral edge of the first base as the holding projections and extend along the axial direction of the rotor core A first holding member having a first leg;
A second base that contacts the other end surface of the rotor core in the axial direction and a plurality of second legs that are provided on the peripheral edge of the second base and extend along the axial direction of the rotor core. A second holding member having
The first leg portion includes an insertion portion that is fitted into the core groove portion, and a protruding portion that protrudes radially outward of the rotor core from the core groove portion in a state where the insertion portion is fitted into the core groove portion, A groove portion provided on a side surface opposite to the insertion portion in the radial direction of the rotor core of the protrusion, and into which the second leg portion is fitted;
The permanent magnet is sandwiched in the axial direction of the rotor core by the first base and the second base, and is sandwiched in the circumferential direction of the rotor core by the protrusion and the positioning protrusion. The rotor according to claim 1 or claim 2.   The rotor according to claim 3, wherein the second leg portion elastically presses the first leg portion toward a radially inner side of the rotor core. The rotor according to any one of claims 1 to 4,
A stator having a plurality of teeth facing the outer peripheral surface of the rotor and a winding wound around the teeth in the radial direction of the rotor;
In a rotating electrical machine in which a plurality of windings respectively correspond to a plurality of different phases,
The rotor core including the positioning protrusion is a magnetic body, and the holding protrusion is a non-magnetic body,
The windings facing the positioning projections in the radial direction of the rotor and the windings facing the holding projections in the radial direction of the rotor correspond to the same phase and include the same The plurality of windings of the phase of the rotating electrical machine are connected in series.   The rotating electrical machine according to claim 5, wherein the rotating electrical machine is a three-phase brushless motor.

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