Rotator of motor

Abstract

To provide a rotator of a motor with suppressed deformation of a rotator core having a rotating shaft press-fitted therein.SOLUTION: A rotator 10 of a motor 100 comprises: a rotating shaft 15 which extends in a vertical direction Z; a rotator core 20, made of a plurality of rotator-side electromagnetic steel plates 25 laminated in the vertical direction Z, which has a press-fitting hole 28 extending in the vertical direction Z and having the rotating shaft 15 press-fitted therein, and a magnet insertion hole 30 located further on the outside in the radial direction than the press-fitting hole 28 and extending in the vertical direction Z; and a magnet 40 inserted into the magnet insertion hole 30. The press-fitting hole 28 has a recess 28A which is recessed to the outside in the radial direction. The rotator core 20 has a first hole 31 which is located further on the outside in the radial direction than the press-fitting hole 28, and is located on a straight line LN1 passing through the center 28C of the press-fitting hole 28 and the center 28AC in the circumferential direction S of the recess 28A.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a rotor of a motor.

Background Art

[0002] For example, Patent Document 1 discloses a rotor of a motor including a rotating shaft, a rotor core composed of a plurality of electromagnetic steel sheets, and a magnet inserted into a magnet insertion hole formed in the rotor core. The rotating shaft of Patent Document 1 is press-fitted into a press-fitting hole formed in the center of the rotor core.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, by press-fitting the rotating shaft into the press-fitting hole formed in the rotor core, a load is applied to the rotor core toward the outside in the radial direction. Due to this load, there is a possibility that the magnet insertion hole and the outer diameter portion of the rotor core may be deformed. For example, when the magnet insertion hole is deformed, there is a possibility that the magnet cannot be inserted into the magnet insertion hole or the magnet cannot be arranged at an appropriate position.

[0005] The present invention has been made in view of such a point, and an object thereof is to provide a rotor of a motor in which deformation of a rotor core into which a rotating shaft is press-fitted is suppressed.

Means for Solving the Problems

[0006] The rotor of the motor according to the present invention has a rotating shaft extending in a first direction, a press-fitting hole extending in the first direction into which the rotating shaft is press-fitted, and a magnet insertion hole located radially outside the press-fitting hole and extending in the first direction. The rotor core is composed of a plurality of electromagnetic steel sheets laminated in the first direction, and a magnet inserted into the magnet insertion hole. A recess recessed radially outward is formed in the press-fitting hole. The rotor core has a first hole located radially outside the press-fitting hole and on a straight line passing through the center of the press-fitting hole and the circumferential center of the recess.

[0007] According to the rotor of the motor according to the present invention, a recess recessed radially outward is formed in the press-fitting hole. As a result, the contact area between the rotating shaft and the press-fitting hole is reduced, so that the load generated when the rotating shaft is press-fitted into the press-fitting hole is reduced. Further, the rotor core has a first hole located radially outside the press-fitting hole and on a straight line passing through the center of the press-fitting hole and the circumferential center of the recess. Here, although the radially outer side of the recess is a portion where a load is likely to be applied, since the first hole is provided in this portion, the load is absorbed at the first hole and the load is suppressed from being transmitted to the radially outer side of the first hole. Thus, by providing the recess and the first hole, deformation of the rotor core can be suppressed.

Effects of the Invention

[0008] According to the present invention, it is possible to provide a rotor of a motor in which deformation of a rotor core into which a rotating shaft is press-fitted is suppressed.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

[0010] Hereinafter, embodiments of the motor according to the present invention will be described with reference to the drawings. It should be noted that the embodiments described herein are not intended to limit the present invention in particular. In addition, members and parts having the same function are denoted by the same reference numerals, and overlapping descriptions are omitted or simplified as appropriate.

[0011] FIG. 1 is a side view of the motor 100. As shown in FIG. 1, the motor 100 includes a rotor 10 and a stator 60 disposed outside the rotor 10 in the radial direction.

[0012] As shown in FIG. 3, the rotor 10 includes a rotating shaft 15, a rotor core 20, a magnet insertion hole 30, a magnet 40, an end plate 50, a first bearing 58, and a second bearing 59.

[0013] As shown in FIG. 3, the rotating shaft 15 extends in the vertical direction Z. The vertical direction Z is an example of the first direction. Here, the downward direction D is an example of one side of the first direction, and the upward direction U is an example of the other side of the first direction. Note that the direction in which the rotating shaft 15 extends is not limited to the vertical direction Z. The protruding length L1 of the rotating shaft 15 downward D from the rotor core 20 is longer than the protruding length L2 of the rotating shaft 15 upward U from the rotor core 20. As shown in FIG. 1, a part (here, the lower end portion 15B) of the rotating shaft 15 protrudes downward D from the stator 60. An output member is attached to the lower end portion 15B of the rotating shaft 15. That is, the lower end portion 15B of the rotating shaft 15 is configured to be able to attach an output member.

[0014] As shown in FIG. 3, the rotor core 20 is an annular member centered on the axis 15C of the rotating shaft 15. The rotor core 20 is fixed to the rotating shaft 15. The rotor core 20 is composed of a plurality of rotor-side electromagnetic steel sheets 25 laminated in the vertical direction Z. The plurality of laminated rotor-side electromagnetic steel sheets 25 are fixed to each other by, for example, caulking, adhesion, welding, etc. The plurality of rotor-side electromagnetic steel sheets 25 are fixed to each other by, for example, caulking. The rotor core 20 has a press-fitting hole 28, a magnet insertion hole 30, a first hole 31 (see FIG. 4), a second hole 32 (see FIG. 4), and a through hole 33 (see FIG. 4). The press-fitting hole 28, the magnet insertion hole 30, the first hole 31, the second hole 32, and the through hole 33 extend in the vertical direction Z.

[0015] As shown in FIG. 3, the thickness T of one rotor-side electromagnetic steel sheet 25 in the vertical direction Z is, for example, 0.15 mm to 0.5 mm. The rotor-side electromagnetic steel sheet 25 is processed into a predetermined shape by punching using a press die. The rotor-side electromagnetic steel sheet 25 includes a plurality of first rotor-side electromagnetic steel sheets 25A laminated in the vertical direction Z and a second rotor-side electromagnetic steel sheet 25B. As will be described later, the second rotor-side electromagnetic steel sheet 25B has the same configuration as the first rotor-side electromagnetic steel sheet 25A except that it does not have the magnet insertion hole 30 and instead has a dropout prevention portion 38 (see FIG. 5). Therefore, for the common part between the first rotor-side electromagnetic steel sheet 25A and the second rotor-side electromagnetic steel sheet 25B, the first rotor-side electromagnetic steel sheet 25A will be described as an example.

[0016] As shown in FIG. 4, the first rotor-side electromagnetic steel sheet 25A is formed in an annular shape. The first rotor-side electromagnetic steel sheet 25A has a press-fitting hole 28, a plurality of magnet insertion holes 30, a plurality of first holes 31, a plurality of second holes 32, and a plurality of through holes 33.

[0017] As shown in FIG. 3, the press-fitting hole 28 is a hole into which the rotating shaft 15 is press-fitted. As shown in FIG. 4, the press-fitting hole 28 is substantially circular in a plan view (i.e., when viewed from the vertical direction Z). A plurality of recesses 28A that are recessed outward in the radial direction are formed in the press-fitting hole 28. The recesses 28A are arranged at equal intervals in the circumferential direction S. The recesses 28A are semi-circular in a plan view. Note that the shape of the recess 28A is not limited to semi-circular.

[0018] As shown in FIG. 3, the magnet insertion hole 30 is a hole into which the magnet 40 is inserted. As shown in FIG. 4, the magnet insertion hole 30 is located outside the press-fitting hole 28 in the radial direction. The magnet insertion hole 30 includes a first magnet hole 30A and a second magnet hole 30B. The first magnet hole 30A is formed in a V shape in a plan view so as to expand toward the outside in the radial direction. The first magnet hole 30A has a first portion 30AA into which one magnet 40 is inserted and a second portion 30AB into which another magnet 40 is inserted. The first portion 30AA, the second portion 30AB, and the second magnet hole 30B are continuous. The second magnet hole 30B extends radially inward from the radially inner end of the first magnet hole 30A. The second magnet hole 30B is located on a straight line LN2 passing through the center 28C of the press-fitting hole 28 and the second hole 32. The straight line LN2 is an example of another straight line. The plurality of magnet insertion holes 30 are arranged at equal intervals in the circumferential direction S. Note that the shape of the magnet insertion hole 30 and the number of magnets 40 inserted into the magnet insertion hole 30 are not limited to those described above. Also, FIG. 4 shows a state in which two magnets 40 are inserted only into the first magnet hole 30A of one magnet insertion hole 30.

[0019] As shown in FIG. 4, the first hole 31 is located outside the press-fitting hole 28 in the radial direction. The first hole 31 is located inside the magnet insertion hole 30 in the radial direction. The first hole 31 is located on a straight line LN1 passing through the center 28C of the press-fitting hole 28 and the center 28AC of the recess 28A in the circumferential direction S. The first hole 31 is substantially trapezoidal in a plan view. The circumferential length SA1 of the radially inner portion of the first hole 31 is longer than the circumferential length SA2 of the radially outer portion of the first hole 31. The plurality of first holes 31 are arranged at equal intervals in the circumferential direction S.

[0020] As shown in Fig. 4, the second hole 32 is located radially outside the press-fitting hole 28. The second hole 32 is located radially inside the magnet insertion hole 30. The second hole 32 is located between the press-fitting hole 28 and the magnet insertion hole 30 in the radial direction. The second hole 32 is substantially trapezoidal in plan view. The length SB1 of the circumferential direction S of the inner portion in the radial direction of the second hole 32 is shorter than the length SB2 of the circumferential direction S of the outer portion in the radial direction of the second hole 32. The plurality of second holes 32 are arranged at equal intervals in the circumferential direction S.

[0021] As shown in Fig. 4, in the circumferential direction S, the first hole 31 and the second hole 32 are alternately arranged. In the circumferential direction S, a part of the first hole 31 and a part of the second hole 32 overlap. The radially inner end 31H of the first hole 31 is located radially inside the radially inner end 32H of the second hole 32. The radially outer end 31J of the first hole 31 is located radially inside the radially outer end 32J of the second hole 32. The length SA1 of the circumferential direction S of the inner portion in the radial direction of the first hole 31 is longer than the length SB1 of the circumferential direction S of the inner portion in the radial direction of the second hole 32. The length SA2 of the circumferential direction S of the outer portion in the radial direction of the first hole 31 is shorter than the length SB2 of the circumferential direction S of the outer portion in the radial direction of the second hole 32.

[0022] As shown in Fig. 4, the through-hole 33 is located radially outside the press-fitting hole 28. The through-hole 33 is located on the straight line LN1. The through-hole 33 is circular in plan view. The through-hole 33 overlaps the first hole 31 in the radial direction. The through-hole 33 overlaps the second magnet hole 30B of the magnet insertion hole 30 in the circumferential direction S. The through-hole 33 includes a first through-hole 33A and a second through-hole 33B that are arranged point-symmetrically with respect to the center 28C of the press-fitting hole 28. The plurality of through-holes 33 are arranged at equal intervals in the circumferential direction S. In the circumferential direction S, the through-hole 33 and the magnet insertion hole 30 are alternately arranged.

[0023] As shown in FIG. 4, the rotor core 20 includes an outer peripheral edge 20A having a plurality of arc portions 20H arranged in the circumferential direction S and a plurality of protruding portions 20B respectively located between adjacent arc portions 20H. The plurality of protruding portions 20B are arranged at equal intervals in the circumferential direction S. The protruding portion 20B is located on the straight line LN1. The protruding portion 20B is located between adjacent magnet insertion holes 30 with respect to the circumferential direction S. The plurality of arc portions 20H are arranged at equal intervals in the circumferential direction S. The arc portion 20H is located on the straight line LN2. The outermost diameter portion 20HM having the largest radius with the center 28C of the press-fitting hole 28 as the center point among the arc portions 20H is located on the straight line LN2. In this embodiment, the radius of the outermost diameter portion 20HM is the same as the radius of the protruding portion 20B, but they may be different.

[0024] As shown in FIG. 3, the second rotor-side electromagnetic steel sheet 25B is provided above U of the uppermost first rotor-side electromagnetic steel sheet 25U among the plurality of laminated first rotor-side electromagnetic steel sheets 25A. Above the second rotor-side electromagnetic steel sheet 25B U the end face plate 50 is not provided. That is, the second rotor-side electromagnetic steel sheet 25B is exposed to the outside. As shown in FIG. 5, the second rotor-side electromagnetic steel sheet 25B has a press-fitting hole 28, a plurality of first holes 31, a plurality of second holes 32, and a plurality of through holes 33. The second rotor-side electromagnetic steel sheet 25B does not include a magnet insertion hole 30 (see FIG. 4). The second rotor-side electromagnetic steel sheet 25B includes a dropout prevention portion 38 that suppresses the dropout (popping out) of the magnet 40 inserted into the magnet insertion hole 30 from the magnet insertion hole 30. The dropout prevention portion 38 overlaps the magnet insertion hole 30 in a plan view. The dropout prevention portion 38 overlaps the entire magnet insertion hole 30 in a plan view.

[0025] As shown in FIG. 3, the magnet 40 is inserted into the magnet insertion hole 30. The magnet 40 extends in the upward direction Z. The magnet 40 is formed in a flat plate shape. The magnet 40 is, for example, a permanent magnet. The magnet 40 is, for example, a rare earth magnet. The magnet 40 is, for example, a neodymium magnet containing neodymium (Nd), iron (Fe), and boron (B).

[0026] As shown in FIG. 3, the length Z1 of the rotor core 20 in the vertical direction Z is longer than the length Z2 of the magnet 40 in the vertical direction Z. The first distance in the vertical direction Z between the lower end 40D of the magnet 40 and the lower end 20D of the rotor core 20 is shorter than the second distance in the vertical direction Z between the upper end 40U of the magnet 40 and the upper end 20U of the rotor core 20. The lower end 40D is an example of one end on one side in the first direction of the magnet 40, and the upper end 40U is an example of one end on the other side in the first direction of the magnet 40. The lower end 20D is an example of one end on one side in the first direction of the rotor core 20, and the upper end 20U is an example of one end on the other side in the first direction of the rotor core 20. The first distance is, for example, 2T or less (i.e., the thickness in the vertical direction Z of two laminated rotor-side electromagnetic steel sheets 25). The second distance is, for example, 3T to 6T. In the present embodiment, the first distance is 0 and the second distance is 5T (i.e., the thickness in the vertical direction Z of five laminated rotor-side electromagnetic steel sheets 25), but the first distance and the second distance are not limited to this.

[0027] As shown in FIG. 3, the end face plate 50 is provided below D of the rotor core 20. The end face plate 50 is provided below the first rotor side electromagnetic steel plate 25D which is located at the lowermost position D among the plurality of first rotor side electromagnetic steel plates 25A of the rotor core 20. The end face plate 50 is fixed to the rotating shaft 15 by press fitting, for example. Note that the end face plate 50 may be fixed to the rotating shaft 15 when the rotor core 20 is press-fitted into the rotating shaft 15. At this time, the end face plate 50 is not press-fitted into the rotating shaft 15. As shown in FIG. 7, the end face plate 50 is formed in a disc shape. The diameter of the end face plate 50 is smaller than the diameter of the rotor side electromagnetic steel plate 25. The end face plate 50 overlaps the entire magnet insertion hole 30 in plan view. The end face plate 50 suppresses the magnet 40 inserted into the magnet insertion hole 30 from dropping (popping out) from below D of the magnet insertion hole 30. The end face plate 50 is made of a non-magnetic material (for example, stainless steel (for example, SUS303)). The thickness H in the vertical direction of the end face plate 50 (see FIG. 3) is thicker than the thickness T of one rotor side electromagnetic steel plate 25. As shown in FIG. 6, a press-fitting hole 52 and a plate hole 54 are formed in the end face plate 50. The press-fitting hole 52 is a hole into which the rotating shaft 15 is press-fitted. The plate hole 54 is a hole into which a mounting jig (not shown) is inserted. The plate hole 54 includes a first plate hole 54A and a second plate hole 54B which are arranged point-symmetrically with respect to the center 52C of the press-fitting hole 52. As shown in FIG. 7, the plate hole 54 overlaps the through hole 33 in plan view. The plate hole 54 does not overlap the magnet insertion hole 30. The first plate hole 54A overlaps the first through hole 33A in plan view, and the second plate hole 54B overlaps the second through hole 33B in plan view. The diameter of the press-fitting hole 52 is larger than the diameter of the plate hole 54.

[0028] As shown in FIG. 1, the stator 60 houses the rotor 10. The stator 60 rotatably supports the rotor 10. As shown in FIG. 2, the stator 60 includes a stator core 70 and a plurality of windings 75 wound around the stator core 70. The stator core 70 is an annular member centered on the axis 15C (see FIG. 3) of the rotating shaft 15. The stator core 70 is fixed to a cover (not shown) of the motor 100. The stator core 70 is composed of a plurality of stator-side electromagnetic steel sheets 80 laminated in the vertical direction Z. The stator-side electromagnetic steel sheets 80 are processed into a predetermined shape by punching using a press die. As shown in FIG. 1, the connection portions 75A between the plurality of windings 75 are located above the rotating shaft 15 (the other side of the vertical direction Z). Note that the plurality of windings 75 may be star-connected or delta-connected. As shown in FIG. 2, the difference between the length Z1 of the rotor core 20 in the vertical direction Z and the length Z3 of the stator core 70 in the vertical direction Z is equal to or less than the thickness 2T of the two laminated rotor-side electromagnetic steel sheets 25 in the vertical direction Z. In the present embodiment, the length Z1 of the rotor core 20 in the vertical direction Z is equal to the length Z3 of the stator core 70 in the vertical direction Z.

[0029] As shown in FIG. 1, the motor 100 includes a rotation sensor 90 that detects the rotation angle of the rotating shaft 15. The rotation sensor 90 is provided on the side of the upper end portion 15A of the rotating shaft 15. The rotation sensor 90 is fixed to the stator 60. Examples of the rotation sensor 90 include a resolver, an encoder, an MR sensor, and the like.

[0030] As shown in FIG. 3, the first bearing 58 and the second bearing 59 are rolling bearings. The first bearing 58 and the second bearing 59 are, for example, ball bearings. The first bearing 58 is a bearing on the load side. The first bearing 58 rotatably supports the rotating shaft 15. The second bearing 59 is a bearing on the non-load side. The second bearing 59 rotatably supports the upper end portion 15A of the rotating shaft 15. The first bearing 58 and the second bearing 59 are fixed to the stator 60 (see FIG. 1).

[0031] As described above, according to the rotor 10 of the motor 100 of the present embodiment, a concave portion 28A that is recessed outward in the radial direction is formed in the press-fitting hole 28. Thereby, since the contact area between the rotary shaft 15 and the press-fitting hole 28 is reduced, the load generated when the rotary shaft 15 is press-fitted into the press-fitting hole 28 is reduced. Further, the rotor core 20 has a first hole 31 that is located radially outside the press-fitting hole 28 and is located on a straight line LN1 passing through the center 28C of the press-fitting hole 28 and the center in the circumferential direction S of the concave portion 28A. Here, although the outside in the radial direction of the concave portion 28A is a portion where a load is likely to be applied, since the first hole 31 is provided in this portion, the load is absorbed in the first hole 31 and the load is transmitted to the outside in the radial direction from the first hole 31. Is suppressed. Thus, by providing the concave portion 28A and the first hole 31, deformation of the rotor core 20 can be suppressed.

[0032] In the rotor 10 of the motor 100 of the present embodiment, the rotor core 20 has a second hole 32 that is located between the press-fitting hole 28 and the magnet insertion hole 30 in the radial direction, and in the circumferential direction S, a part of the first hole 31 and a part of the second hole 32 overlap. According to the above aspect, since the load generated when the rotary shaft 15 is press-fitted into the press-fitting hole 28 is absorbed in the second hole 32, the load is transmitted to the magnet insertion hole 30 located outside the second hole 32 in the radial direction. Is suppressed. Further, in the circumferential direction S, since a part of the first hole 31 and a part of the second hole 32 overlap, compared with the case where the first hole 31 and the second hole 32 are completely displaced in the circumferential direction S, the first hole 31 and the second hole 32 are more radially displaced. The transmission of the load to the outside is suppressed.

[0033] In the rotor 10 of the motor 100 of the present embodiment, the length SA1 in the circumferential direction S of the inner portion in the radial direction of the first hole 31 is longer than the length SB1 in the circumferential direction S of the inner portion in the radial direction of the second hole 32. According to the above aspect, the load generated when the rotary shaft 15 is press-fitted into the press-fitting hole 28 is better absorbed in the first hole 31.

[0034] In the rotor 10 of the motor 100 according to the present embodiment, the radially inner end portion 31H of the first hole 31 is located radially inward of the radially inner end portion 32H of the second hole 32, and the radially outer end portion 31J of the first hole 31 is located radially inward of the radially outer end portion 32J of the second hole 32. According to the above aspect, the load generated when the rotary shaft 15 is press-fitted into the press-fitting hole 28 is better absorbed in the first hole 31.

[0035] In the rotor 10 of the motor 100 according to the present embodiment, the first hole 31 and the second hole 32 are substantially trapezoidal in plan view. According to the above aspect, the load generated when the rotary shaft 15 is press-fitted into the press-fitting hole 28 is better absorbed in the first hole 31 and the second hole 32.

[0036] In the rotor 10 of the motor 100 according to the present embodiment, the length SA1 in the circumferential direction S of the radially inner portion of the first hole 31 is longer than the length SA2 in the circumferential direction S of the radially outer portion of the first hole 31, and the length in the circumferential direction S of the radially inner portion of the second hole 32 is shorter than the length SB2 in the circumferential direction S of the radially outer portion of the second hole 32. According to the above aspect, the load generated when the rotary shaft 15 is press-fitted into the press-fitting hole 28 is absorbed in a well-balanced manner in the first hole 31 and the second hole 32.

[0037] In the rotor 10 of the motor 100 according to the present embodiment, the rotor core 20 has a through hole 33 that is located radially outside the first hole 31 and is located on the straight line LN1. According to the above aspect, it is possible to suppress the load generated when the rotary shaft 15 is press-fitted into the press-fitting hole 28 from being absorbed in the through hole 33 and transmitted radially outside the through hole 33. As a result, deformation of the outer peripheral portion (for example, the outer peripheral edge 20A) of the rotor core 20 is more reliably suppressed. Further, when the magnet 40 is inserted into the magnet insertion hole 30, the through hole 33 can be used as a hole for positioning the magnet 40.

[0038] In the rotor 10 of the motor 100 according to this embodiment, the rotor core 20 includes an outer peripheral edge 20A having a plurality of arc portions 20H arranged in the circumferential direction S and a plurality of protruding portions 20B respectively located between adjacent arc portions 20H. The protruding portions 20B are located on the straight line LN1. According to the above aspect, deformation of the protruding portions 20B is more reliably suppressed.

[0039] In the rotor 10 of the motor 100 according to this embodiment, the through hole 33 is circular in plan view. According to the above aspect, the load generated when the rotary shaft 15 is press-fitted into the press-fitting hole 28 is better absorbed in the through hole 33.

[0040] In the rotor 10 of the motor 100 according to this embodiment, the through hole 33 includes a first through hole 33A and a second through hole 33B that are arranged point-symmetrically with respect to the center 28C of the press-fitting hole 28. The plate hole 54 includes a first plate hole 54A that overlaps the first through hole 33A and a second plate hole 54B that overlaps the second through hole 33B in plan view. According to the above aspect, when magnetizing the magnet 40, the first through hole 33A and the first plate hole 54A and the second through hole 33B and the second plate hole 54B can be used for positioning the magnetizing coil and the magnet 40.

[0041] In the rotor 10 of the motor 100 according to this embodiment, the magnet insertion hole 30 includes a first magnet hole 30A formed in a V shape in plan view so as to widen toward the outer side in the radial direction, and a second magnet hole 30B extending from the radially inner end of the first magnet hole 30A toward the radially inner side. The second magnet hole 30B is located on a straight line LN2 passing through the center 28C of the press-fitting hole 28 and the second hole 32. According to the above aspect, when the rotary shaft 15 is press-fitted into the press-fitting hole 28, the load generated is absorbed in the second magnet hole 30B, and it is suppressed that the load is transmitted to the first magnet hole 30A located more radially outside than the second magnet hole 30B. Thereby, deformation of the first magnet hole 30A is more reliably suppressed.

[0042] In the rotor 10 of the motor 100 of the present embodiment, the outermost diameter portion 20HM having the largest radius with the center 28C of the press-fitting hole 28 as the center point among the arc portions 20H is located on the straight line LN2. According to the above aspect, deformation of the outermost diameter portion 20HM is more reliably suppressed.

[0043] In the rotor 10 of the motor 100 of the present embodiment, the protruding portion 20B is located on the straight line LN1, and the outermost diameter portion 20HM having the largest radius with the center 28C of the press-fitting hole 28 as the center point among the arc portions 20H is located on the straight line LN2. According to the above aspect, deformation of the protruding portion 20B and the outermost diameter portion 20HM is more reliably suppressed. That is, deformation of the outer peripheral edge 20A is more reliably suppressed.

[0044] In the rotor 10 of the motor 100 of the present embodiment, the recessed portion 28A is semi-circular in plan view. According to the above aspect, it is possible to ensure the strength of the press-fitting hole 28 while reducing the contact area between the rotary shaft 15 and the press-fitting hole 28.

[0045] The preferred embodiments of the present invention have been described above. However, the above-described embodiments are merely examples, and the present invention can be implemented in various other forms.

[0046] In the above-described embodiment, the rotor 10 includes the end face plate 50 provided below the rotor core 20, but the rotor 10 may include another end face plate having the same configuration as the end face plate 50 above the rotor core 20.

[0047] In the above-described embodiment, the inner end portion 31H in the radial direction of the first hole 31 is located more radially inward than the inner end portion 32H in the radial direction of the second hole 32, and the outer end portion 31J in the radial direction of the first hole 31 is located more radially inward than the outer end portion 32J in the radial direction of the second hole 32, but it is not limited thereto. For example, the inner end portion 31H in the radial direction of the first hole 31 may be located more radially outward than the inner end portion 32H in the radial direction of the second hole 32, and the outer end portion 31J in the radial direction of the first hole 31 may be located more radially outward than the outer end portion 32J in the radial direction of the second hole 32.

[0048] In the above-described embodiment, the length SA1 in the circumferential direction S of the inner portion in the radial direction of the first hole 31 is longer than the length SB1 in the circumferential direction S of the inner portion in the radial direction of the second hole 32, and the length SA2 in the circumferential direction S of the outer portion in the radial direction of the first hole 31 is shorter than the length SB2 in the circumferential direction S of the outer portion in the radial direction of the second hole 32. However, the present invention is not limited thereto. For example, the length SA1 in the circumferential direction S of the inner portion in the radial direction of the first hole 31 may be shorter than the length SB1 in the circumferential direction S of the inner portion in the radial direction of the second hole 32, and the length SA2 in the circumferential direction S of the outer portion in the radial direction of the first hole 31 may be longer than the length SB2 in the circumferential direction S of the outer portion in the radial direction of the second hole 32.

Explanation of Signs

[0049] 10 Rotor 15 Rotation shaft 20 Rotor core 25 Rotor-side electromagnetic steel sheet 28 Press-fit hole 28C Center 28A Recess 28AC Center 30 Magnet insertion hole 30A First magnet hole 30B Second magnet hole 31 First hole 32 Second hole 33 Through hole 33A First through hole 33B Second through hole 40 Magnet 50 End plate 52 Press-fit hole 54 Plate hole 54A First plate hole 54B Second plate hole 60 Stator 70 Stator core 75 Coil 75A Connection part 90 Rotation sensor 100 Motor

Claims

1. A rotating shaft extending in a first direction, a press-fitting hole extending in the first direction into which the rotating shaft is press-fitted, and a magnet insertion hole located radially outside the press-fitting hole and extending in the first direction, and a rotor core composed of a plurality of electromagnetic steel sheets laminated in the first direction, a magnet inserted into the magnet insertion hole, a recess recessed radially outward is formed in the press-fitting hole, The rotor core has a first hole located radially outside the press-fitting hole and on a straight line passing through the center of the press-fitting hole and the circumferential center of the recess, and is a rotor of a motor.

2. The rotor core has a second hole located between the press-fitting hole and the magnet insertion hole in the radial direction, In the circumferential direction, a part of the first hole and a part of the second hole overlap, and the rotor of the motor according to claim 1.

3. The circumferential length of the radially inner portion of the first hole is longer than the circumferential length of the radially inner portion of the second hole, and the rotor of the motor according to claim 2.

4. The radially inner end of the first hole is located radially inward of the radially inner end of the second hole, The radially outer end of the first hole is located radially inward of the radially outer end of the second hole, and the rotor of the motor according to claim 2 or 3.

5. The first hole and the second hole are substantially trapezoidal when viewed from the first direction, and the rotor of the motor according to claim 2 or 3.

6. The circumferential length of the radially inner portion of the first hole is longer than the circumferential length of the radially outer portion of the first hole, The circumferential length of the radially inner portion of the second hole is shorter than the circumferential length of the radially outer portion of the second hole, and the rotor of the motor according to claim 5.

7. The rotor core has a through hole located radially outside the first hole and on the straight line, and the rotor of the motor according to claim 1 or 2.

8. The rotor core has an outer peripheral edge having a plurality of arc portions arranged in the circumferential direction and a plurality of protruding portions respectively located between adjacent arc portions, The protruding portion is located on the straight line, and the rotor of the motor according to claim 7.

9. The through hole is circular when viewed from the first direction, and the rotor of the motor according to claim 7.

10. It is provided on one side of the rotor core in the first direction and includes an end face plate that suppresses the magnet inserted into the magnet insertion hole from falling off from one side in the first direction. The end face plate is formed with the press-fitting hole and a plate hole that overlaps the through hole when viewed from the first direction. The through hole includes a first through hole and a second through hole that are arranged point-symmetrically with respect to the center of the press-fitting hole. The plate hole includes a first plate hole that overlaps the first through hole when viewed from the first direction and a second plate hole that overlaps the second through hole. The rotor of the motor according to claim 7.

11. The rotor core has a second hole located between the press-fitting hole and the magnet insertion hole in the radial direction. The magnet insertion hole includes a first magnet hole formed in a V shape when viewed from the first direction so as to expand toward the outside in the radial direction, and a second magnet hole extending inward in the radial direction from the inner end in the radial direction of the first magnet hole. The rotor of the motor according to claim 1. The second magnet hole is located on a straight line passing through the center of the press-fitting hole and the second hole.

12. The rotor core includes an outer peripheral edge having a plurality of arc portions arranged in the circumferential direction. The outermost diameter portion having the largest radius with the center of the press-fitting hole as the center point among the arc portions is located on the other straight line. The rotor of the motor according to claim 11.

13. The rotor core includes a second hole located between the press-fitting hole and the magnet insertion hole in the radial direction, a through hole located outside the first hole in the radial direction and on the straight line, and an outer peripheral edge having a plurality of arc portions arranged in the circumferential direction and a plurality of protruding portions respectively located between adjacent arc portions. The protruding portion is located on the straight line. The outermost diameter portion having the largest radius with the center of the press-fitting hole as the center point among the arc portions is located on a straight line passing through the center of the press-fitting hole and the second hole. The rotor of the motor according to claim 1.

14. The recess is semicircular when viewed from the first direction. The rotor of the motor according to claim 1 or 2.

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