WO2023176199A1

WO2023176199A1 - Rotor and electric motor

Info

Publication number: WO2023176199A1
Application number: PCT/JP2023/004025
Authority: WO
Inventors: 宏之吉村; 崇弘大橋
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2022-03-14
Filing date: 2023-02-07
Publication date: 2023-09-21

Abstract

Provided are a rotor and an electric motor with which it is possible to increase the adhesive strength between permanent magnets and a rotor core. A rotor (3) comprises a rotor core (9), permanent magnets (11), an adhesive (16), and a rotary shaft. The adhesive (16) is positioned between the rotor core (9) and the permanent magnets (11), and fixes the permanent magnets (11) to the rotor core (9). The rotary shaft (10) is fixed to the rotor core (9), and rotates about an axis (14). The adhesive (16) includes a first adhesive layer (31) and a second adhesive layer (32). The first adhesive layer (31) and the second adhesive layer (32) are arranged one after the other in the direction of extension of the axis of the rotary shaft, and have a bottom edge (33) and a top edge (34) that are opposite one another with a distance therebetween.

Description

Rotor and electric motor

The present disclosure relates to a rotor and an electric motor, and particularly relates to a rotor including a permanent magnet and an electric motor including a rotor.

Patent Document 1 describes a rotor that includes permanent magnets. A magnet embedding hole (magnet placement hole) is formed in the rotor core of the rotor. A permanent magnet is fixed to the magnet embedding hole with an adhesive.

JP2017-192222A

However, when the rotor described in Patent Document 1 becomes longer in the axial direction of the rotating shaft, the area of the adhesive also becomes longer in the axial direction. When the length of the adhesive exceeds a certain length in the axial direction, the increase in strength against stress becomes saturated in the axial direction due to stress concentration at the end of the adhesive layer in the axial direction. In other words, as the adhesive application area increases, the stress increases, but the adhesive strength does not change. Therefore, the adhesive strength per unit area of the adhesive decreases.

The present disclosure has been made in view of the above points, and an object of the present disclosure is to provide a rotor and a motor that can increase the adhesive strength between a permanent magnet and a rotor core.

A rotor according to one aspect of the present disclosure includes a rotor core, a permanent magnet, an adhesive, and a rotating shaft. The permanent magnet is arranged close to the rotor core. The adhesive is placed between the rotor core and the permanent magnet, and fixes the permanent magnet to the rotor core. The rotation shaft is fixed to the rotor core, and has an axis as the center of rotation. The adhesive has multiple adhesive layers. The plurality of adhesive layers are arranged in a line in a direction in which the axial center of the rotating shaft extends, and each has at least partially opposite edges spaced apart from each other.

An electric motor according to another aspect of the present disclosure includes the rotor and stator.

According to the rotor and electric motor according to the above aspects of the present disclosure, the adhesive strength between the permanent magnet and the rotor core can be increased.

FIG. 1 is a schematic top view of the electric motor according to the first embodiment. FIG. 2 is a perspective view of the rotor of the electric motor according to the first embodiment. FIG. 3 is a partial sectional view of the rotor of the electric motor according to the first embodiment. FIG. 4 is a partial cross-sectional view of the rotor according to the first modification. FIG. 5 is a partial sectional view of a rotor according to a second modification. FIG. 6 is a partial sectional view of a rotor according to a third modification. FIG. 7 is a schematic top view of the electric motor according to the second embodiment. FIG. 8 is a perspective view of the rotor of the electric motor according to the second embodiment. FIG. 9 is a partial sectional view of the rotor of the electric motor according to the second embodiment. FIG. 10 is a partial sectional view of a rotor according to a fourth modification. FIG. 11 is a partial sectional view of a rotor according to a fifth modification. FIG. 12 is a partial sectional view of a rotor according to a sixth modification. FIG. 13 is a schematic diagram of the electric motor and the power source that supplies current to the electric motor according to the first embodiment.

(Embodiment)
Hereinafter, a rotor and an electric motor according to embodiments of the present disclosure will be described in detail with reference to the drawings. However, each figure described in the following embodiments is a schematic diagram, and the respective ratios of the sizes and thicknesses of each component do not necessarily reflect the actual size ratios. Note that the configuration described in the embodiments below is only an example of the present disclosure. The present disclosure is not limited to the following embodiments, and various changes can be made depending on the design etc. as long as the effects of the present disclosure can be achieved.

(First embodiment)
(1) Overview of Electric Motor An electric motor 1 according to a first embodiment of the present disclosure will be described using FIGS. 1 to 3. The electric motor 1 is an inner rotor type motor.

FIG. 1 is a schematic top view of the electric motor 1 according to the first embodiment. FIG. 2 is a perspective view of the rotor 3 of the electric motor 1 according to the first embodiment. FIG. 3 is a partial sectional view of the rotor 3 of the electric motor 1 according to the first embodiment.

The electric motor 1 has a stator 2 and a rotor 3. In the following description, the direction in which the axis 14 (described later) of the rotating shaft 10 (described later) extends is referred to as an axial direction A1, and the circumferential direction of the rotor 3 is referred to as a circumferential direction C1. Further, a direction along a line segment connecting a point on a plane perpendicular to the axis 14 and an intersection of the plane and the axis 14 is referred to as a radial direction F1. At any one point included in the electric motor 1, the axial direction A1, the circumferential direction C1, and the radial direction F1 are orthogonal to each other.

The stator 2 is a stator that has a stator core 4 and a plurality of (nine in FIG. 1) coil windings 6. The stator core 4 is a laminated core in which a plurality of steel plates are laminated in the thickness direction. The stator core 4 is formed into a substantially cylindrical column shape. The stator core 4 includes an annular core back 7 and a plurality of (nine in FIG. 1) core backs arranged on the inner peripheral surface of the core back 7 at regular intervals along the circumferential direction C1 and extending in the radial direction F1 and toward the axis 14. It has teeth 8. Each coil winding 6 is wound around one corresponding tooth 8.

The rotor 3 is an IPM (Interior Permanent Magnet) type rotor in which a permanent magnet is embedded inside the rotor core. The rotor 3 is arranged closer to the axis 14 than the stator 2 in the radial direction F1, and includes a rotor core 9, a rotating shaft 10, and a plurality of permanent magnets 11.

FIG. 13 shows a schematic diagram of a power supply 100 that supplies current to the electric motor 1. The electric motor 1 operates as follows. A cable 101 extends from a power supply 100 to the electric motor 1, and current is supplied through a power supply connection part 102. More specifically, three-phase currents having a phase difference of 120 degrees in electrical angle are supplied to the plurality of coil windings 6 through the power supply connection part 102, respectively, to excite the stator 2 and generate a rotating magnetic field. do. This rotating magnetic field interacts with the magnetic field generated by the permanent magnet 11 provided on the rotor 3 to generate rotational torque in the rotor 3, and as a result, the rotor 3 rotates around the axis 14. .

(2) Rotor As shown in FIG. 2, the rotor core 9 is a laminated core in which a plurality of steel plates 17 are laminated in the thickness direction. The rotor core 9 has a circular center shaft hole 12 and is formed in a cylindrical shape.

A plurality of magnet arrangement holes 13 are formed in the rotor core 9 and arranged in the circumferential direction C1. The opening shape of the magnet arrangement hole 13 is a substantially rectangular parallelepiped. In this embodiment, the magnet placement hole 13 penetrates in the axial direction A1, but may have a bottom.

The rotating shaft 10 is a cylindrical member and has an axis 14 that is the center of rotation. The rotating shaft 10 is inserted into a central shaft hole 12 of the rotor core 9 and is fixed therein.

A plurality of (10 in FIG. 1) permanent magnets 11 are inserted and fixed into the plurality of magnet placement holes 13 of the rotor core 9, respectively. Each permanent magnet 11 has, for example, a rectangular parallelepiped shape. As the permanent magnet 11, a samarium-cobalt permanent magnet, a neodymium magnet, or the like can be used, and a neodymium magnet is suitable for use in an automobile motor.

FIG. 3 is a cross-sectional view of FIG. 2 taken along a plane that passes through the rotor core 9 and the permanent magnets 11 and includes the III-III line segment along the radial direction F1 and is perpendicular to the circumferential direction C1. As shown in FIG. 3, the rotor 3 has an adhesive 16 for fixing the permanent magnets 11 to the magnet placement holes 13. The adhesive 16 is filled in the gap between the inner surface 25 of the magnet placement hole 13 and the outer surface 26 of the permanent magnet 11. The adhesive 16 is, for example, a thermosetting resin, and specifically may be, for example, an epoxy resin or a silicone resin.

The adhesive 16 has a first adhesive layer 31 and a second adhesive layer 32, as shown in FIG. In the axial direction A1, the first adhesive layer 31 is arranged above the second adhesive layer 32 in the paper of FIG. 3, and the second adhesive layer 32 is arranged below the first adhesive layer 31 in the paper of FIG. has been done. The first adhesive layer 31 and the second adhesive layer 32 are each formed on the outer surface 26 of the permanent magnet 11. Note that the first adhesive layer 31 and the second adhesive layer 32 only need to be formed on at least a portion of the outer surface 26 of the permanent magnet 11. For example, each of the first adhesive layer 31 and the second adhesive layer 32 may be formed in an annular shape around the outer surface 26. Alternatively, each of the first adhesive layer 31 and the plurality of second adhesive layers 32 may be divided into a plurality of parts and formed so as to be lined up in the circumferential direction around the outer surface 26. Alternatively, each of the first adhesive layer 31 and the plurality of second adhesive layers 32 may be formed only on one surface of the outer surface 26. The lower edge 33 of the first adhesive layer 31 and the upper edge 34 of the second adhesive layer 32 face each other at a distance over the entire circumference. In other words, the gap 35 exists between the first adhesive layer 31 and the second adhesive layer 32 in the axial direction A1.

By dividing the adhesive 16 in the axial direction A1 as described above, the possibility of strength saturation can be reduced. This is because the first adhesive layer 31 and the second adhesive layer 32 are shorter in the axial direction A1 than the length at which strength saturation occurs due to stress concentration at the ends. As a result of the above, even if the area where the adhesive 16 is applied is large, the possibility that the adhesive strength per unit area will decrease can be reduced. As a result, even in the rotor core 9 which is long in the axial direction A1, the permanent magnets 11 can be bonded with a strength corresponding to the bonding area.

(3) Rotor manufacturing method A manufacturing method of the rotor 3 will be explained.

As a first step, a rotor core 9 having a plurality of magnet placement holes 13 is prepared.

As a second step, the permanent magnets 11 are inserted into each of the plurality of magnet placement holes 13 in the rotor core 9.

As a third step, the permanent magnets 11 are fixed to the rotor core 9 by applying adhesive 16 to the gap between the inner surface 25 of the magnet arrangement hole 13 of the rotor core 9 and the outer surface 26 of the permanent magnet 11. In this case, the adhesive 16 is supplied to a predetermined position so that a gap 35 is secured between the first adhesive layer 31 and the second adhesive layer 32 by controlling the viscosity depending on the type and temperature of the adhesive. Alternatively or in addition, the wettability of the middle part of the protective film of the permanent magnet 11 is made worse than that of the upper and lower parts, so that the gap 35 is secured between the first adhesive layer 31 and the second adhesive layer 32. The adhesive 16 may be supplied to a predetermined position.

Note that instead of the second and third steps, the permanent magnet 11 coated with the adhesive 16 in advance may be inserted into the magnet placement hole 13.

As a fourth step, the rotating shaft 10 is attached to the rotor core 9. Specifically, the rotating shaft 10 is fixed to the central shaft hole 12 of the rotor core 9.

(4) Modifications The embodiment described above is just one of various embodiments of the present disclosure. The embodiments described above can be modified in various ways depending on the design, etc., as long as the objective of the present disclosure can be achieved. Modifications of the above embodiment will be listed below. The modified examples described below can be applied in combination as appropriate. In addition, regarding the following modified examples, a schematic top view of the electric motor 1 is a drawing similar to FIG. 1, and a perspective view of the rotor 3 is a drawing similar to FIG. 2.

(4-1) First modification example In the first embodiment, there were two adhesive layers (first adhesive layer 31, second adhesive layer 32), but since it is sufficient to have multiple adhesive layers, three or more adhesive layers are required. It may be.

Such an example will be described as a first modification using FIG. 4. FIG. 4 is a partial cross-sectional view of the rotor 3 according to the first modification, and is a diagram similar to FIG. 3.

The adhesive 40 is filled in the gap between the inner surface 25 of the magnet placement hole 13 and the outer surface 26 of the permanent magnet 11. As shown in FIG. 4, the adhesive 40 includes a first adhesive layer 41, a second adhesive layer 42, a third adhesive layer 43, a fourth adhesive layer 44, and a fifth adhesive layer 45. The first adhesive layer 41 to the fifth adhesive layer 45 are arranged in this order from top to bottom in the axial direction A1 in the gap between the inner surface 25 of the magnet arrangement hole 13 and the outer surface 26 of the permanent magnet 11. Each of the first adhesive layer 41 to the fifth adhesive layer 45 is formed around the outer surface 26 of the permanent magnet 11. The lower edge 61 of the first adhesive layer 41 and the upper edge 62 of the second adhesive layer 42, the lower edge 63 of the second adhesive layer 42, the upper edge 64 of the third adhesive layer 43, and the lower edge 65 of the third adhesive layer 43. The upper edge 66 of the fourth adhesive layer 44, the lower edge 67 of the fourth adhesive layer 44, and the upper edge 68 of the fifth adhesive layer 45 are each opposed to each other with a distance between them. In other words,

gaps

71, 72, 73, and 74 exist in the axial direction A1 between adjacent adhesive layers. Note that the first to fifth adhesive layers 41 to 45 only need to be formed on at least a portion of the outer surface 26 of the permanent magnet 11. For example, each of the first adhesive layer 41 to the fifth adhesive layer 45 may be formed in an annular shape around the outer surface 26. Alternatively, each of the first adhesive layer 41 to the fifth adhesive layer 45 may be divided into a plurality of parts and arranged circumferentially around the outer surface 26. Alternatively, each of the first adhesive layer 41 to the fifth adhesive layer 45 may be formed only on one surface of the outer surface 26.

The same effects as the first embodiment can be obtained in the first modification.

(4-2) Second modification example In the first embodiment, there was a gap 35 between the first adhesive layer 31 and the second adhesive layer 32, but since the two adhesive layers only need to be separated, other It may be filled with a member.

Such an example will be described as a second modification using FIG. 5. FIG. 5 is a partial sectional view of the rotor 3 according to the second modification, and is a diagram similar to FIG. 3.

In addition to the configuration of the first embodiment, the rotor 3 further includes a blocking member 51. The blocking member 51 is a member for separating the edge of the first adhesive layer 31 and the edge of the second adhesive layer 32 by blocking the first adhesive layer 31 and the second adhesive layer 32 from each other. The blocking member 51 has a rectangular cylindrical shape and is located between the inner surface 25 of the magnet arrangement hole 13 and the outer surface 26 of the permanent magnet 11. is placed between. In this way, the blocking member 51 blocks the first adhesive layer 31 and the second adhesive layer 32 from each other.

The blocking member 51 is, for example, fitted and fixed to the permanent magnet 11. Specifically, the blocking member 51 is made of resin or metal, for example, and is provided at an intermediate portion of the outer surface 26 of the permanent magnet 11 in the axial direction A1. Note that the blocking member 51 only needs to correspond to the first adhesive layer 31 and the second adhesive layer 32. That is, the shielding member 51 may be provided in an annular shape around the outer surface 26 in accordance with the configuration of the first adhesive layer 31 and the second adhesive layer 32, or a plurality of shielding members 51 may be arranged circumferentially around the outer surface 26. It may be provided on only one surface of the outer surface 26.

In the second modification, the shielding member 51 facilitates positioning of the first adhesive layer 31 and the second adhesive layer 32, so manufacturing of the rotor 3 is simplified.

In addition, in the second modification, the manufacturing method in which the first adhesive layer 31 and the second adhesive layer 32 are first applied to the permanent magnet 11 and then inserted into the magnet placement hole 13 becomes easier.

(4-3) Third Modification Example With reference to FIG. 6, another example in which two adhesive layers are blocked by another member will be described as a third modification example. FIG. 6 is a partial cross-sectional view of the rotor 3 according to the third modification, and is a diagram similar to FIG. 3.

In addition to the configuration of the first embodiment, the rotor 3 further includes a blocking member 52. The blocking member 52 is a member for separating the edges of the adhesive layers by blocking the plurality of adhesive layers from each other. The blocking member 52 is disposed between the inner surface 25 of the magnet arrangement hole 13 and the outer surface 26 of the permanent magnet 11 and between the lower edge 33 of the first adhesive layer 31 and the upper edge 34 of the second adhesive layer 32. There is. In this way, the blocking member 52 blocks the first adhesive layer 31 and the second adhesive layer 32 from each other.

The blocking member 52 is integrated with the rotor core 9. That is, the blocking member 52 is a protrusion that protrudes toward the axial center 14 in the radial direction F1 from the intermediate portion in the axial direction A1 of the inner surface 25 of the magnet arrangement hole 13 of the rotor core 9 of the first embodiment. Note that the blocking member 52 only needs to correspond to the first adhesive layer 31 and the second adhesive layer 32. That is, the shielding member 52 may be formed in an annular shape around the inner surface 25 in accordance with the configuration of the first adhesive layer 31 and the second adhesive layer 32, or may be formed in a plurality of shielding members arranged circumferentially around the inner surface 25. or may be formed only on one surface of the inner surface 25.

In the third modification, the shielding member 52 facilitates positioning of the first adhesive layer 31 and the second adhesive layer 32, so manufacturing of the rotor 3 is simplified.

(Second embodiment)
(1) Electric Motor An electric motor 1A according to a second embodiment of the present disclosure will be described using FIGS. 7 to 9. Note that since the explanation will focus on the differences from the first embodiment, the explanation will be omitted as appropriate by assigning the same or corresponding numerals to the same configurations. FIG. 7 is a schematic top view of an electric motor 1A according to the second embodiment. FIG. 8 is a perspective view of a rotor 3A of a power transmitter 1A according to the second embodiment. FIG. 9 is a partial sectional view of a rotor 3A of a power transmitter 1A according to the second embodiment.

The electric motor 1A has a stator 2A and a rotor 3A. The stator 2A is a stator that has a stator core 4A and a plurality of coil windings 6A.

(2) Rotor The rotor 3A is of the SPM (Surface Permanent Magnet) type in which a plurality of permanent magnets are arranged on the outer peripheral surface of the rotor core. The rotor 3A includes a rotor core 9A, a permanent magnet 11A, and a rotating shaft 10A.

The permanent magnet 11A has a cylindrical shape and is provided on the outer peripheral surface 37A of the rotor core 9A. The permanent magnet 11A has a plurality of N poles and S poles located alternately in the circumferential direction C1.

FIG. 9 shows a cross-sectional view of FIG. 8 taken along a plane that passes through the rotor core 9A and the permanent magnet 11A, includes the IX-IX line segment along the radial direction F1, and is perpendicular to the circumferential direction C1. As shown in FIG. 9, the rotor 3A has an adhesive 16A for fixing the permanent magnet 11A to the outer peripheral surface 37A of the rotor core 9A. The adhesive 16A is filled in the gap between the outer peripheral surface 37A of the rotor core 9A and the inner peripheral surface 38A of the permanent magnet 11A.

As shown in FIG. 9, the adhesive 16A has a first adhesive layer 31A and a second adhesive layer 32A. The first adhesive layer 31A and the second adhesive layer 32A are arranged side by side in the axial direction A1, and the first adhesive layer 31A is arranged on the second adhesive layer 32A in the paper of FIG. A second adhesive layer 32A is disposed below the first adhesive layer 31A. The first adhesive layer 31A and the second adhesive layer 32A are each formed continuously or intermittently in the circumferential direction C1 on the outer peripheral surface 37A of the rotor core 9A. However, the lower edge 33A of the first adhesive layer 31A and the upper edge 34A of the second adhesive layer 32A face each other at a distance over the entire circumference. In other words, a gap 35A in the axial direction A1 exists between the first adhesive layer 31A and the second adhesive layer 32A.

By dividing the adhesive 16A in the axial direction A1 as described above, strength saturation can be avoided. Thereby, even if the applied area of the adhesive 16A is large, the adhesive strength per unit area does not decrease. As a result, even in the rotor core 9A which is long in the axial direction A1, the permanent magnet 11A can be bonded with a strength corresponding to the bonding area.

Note that the permanent magnet 11A may be a plurality of permanent magnets divided in the circumferential direction C1. In that case, the adhesive layers of all the permanent magnets may be divided in the axial direction, or the adhesive layers of some permanent magnets may be divided in the axial direction.

(3) Modifications Modifications of the second embodiment described above will be listed below. The modified examples described below can be applied in combination as appropriate. Regarding the following modifications, a schematic top view of the electric motor 1A is similar to FIG. 7, and a perspective view of the rotor 3A is similar to FIG. 8.

(3-1) Fourth modification example In the second embodiment, there were two adhesive layers (first adhesive layer 31A, second adhesive layer 32A), but since it is sufficient to have multiple adhesive layers, there are three or more adhesive layers. It may be.

Such an example will be described as a fourth modification using FIG. 10. FIG. 10 is a partial sectional view of a rotor 3A according to a fourth modification, and is a drawing similar to FIG. 9.

The adhesive 40A is filled in the gap between the inner surface 25 of the magnet placement hole 13 and the outer surface 26 of the permanent magnet 11. As shown in FIG. 10, the adhesive 40A includes a first adhesive layer 41A, a second adhesive layer 42A, a third adhesive layer 43A, a fourth adhesive layer 44A, and a fifth adhesive layer 45A. The first adhesive layer 41A to the fifth adhesive layer 45A are arranged in this order from top to bottom in the axial direction A1 in the gap between the outer peripheral surface 37A of the rotor core 9A and the inner peripheral surface 38A of the permanent magnet 11A. There is. The first adhesive layer 41A to the fifth adhesive layer 45A are each formed continuously or intermittently in the circumferential direction C1 on the outer peripheral surface 37A of the rotor core 9A. However, the lower edge 61A of the first adhesive layer 41A, the upper edge 62A of the second adhesive layer 42A, the lower edge 63A of the second adhesive layer 42A, the upper edge 64A of the third adhesive layer 43A, and the lower edge of the third adhesive layer 43A. 65A and the upper edge 66A of the fourth adhesive layer 44A, and the lower edge 67A of the fourth adhesive layer 44A and the upper edge 68A of the fifth adhesive layer 45A, respectively, face each other at a distance over the entire circumference. In other words, there are a gap 71A, a gap 72A, a gap 73A, and a gap 74A in the axial direction A1 between the adhesive layers.

The same effects as the second embodiment can be obtained in the fourth modification.

(3-2) Fifth modification example In the first embodiment, there was a gap between the two adhesive layers, but since it is sufficient that the edges of the two adhesive layers are separated from each other, the gap can be filled with other members. You can leave it there.

Such an example will be described as a fifth modification using FIG. 11. FIG. 11 is a partial sectional view of a rotor 3A according to a fifth modification, and is a drawing similar to FIG. 9.

In addition to the configuration of the second embodiment, the rotor 3A further includes a blocking member 51A. The blocking member 51A is a member for separating the edges of the adhesive layers by blocking the plurality of adhesive layers from each other. The blocking member 51A has a cylindrical shape, and is located between the lower edge 33A of the first adhesive layer 31A and the upper edge 34A of the second adhesive layer 32A in the gap between the outer peripheral surface 37A of the rotor core 9A and the inner peripheral surface 38A of the permanent magnet 11A. is located between. In this way, the blocking member 51A blocks the first adhesive layer 31A and the second adhesive layer 32A.

The blocking member 51A is fixed to the permanent magnet 11A. Specifically, the blocking member 51A is made of resin, for example, and is provided at an intermediate portion in the axial direction A1 of the inner circumferential surface 38A of the permanent magnet 11A.

In the fifth modification, the shielding member 51A facilitates positioning of the first adhesive layer 31A and the second adhesive layer 32A, thereby simplifying the manufacture of the rotor 3A.

(3-3) Sixth Modification Example With reference to FIG. 12, another example in which two adhesive layers are blocked by another member will be described as a sixth modification example. FIG. 12 is a partial sectional view of a rotor 3A according to a sixth modification, and is a drawing similar to FIG. 9.

In addition to the configuration of the second embodiment, the rotor 3A further includes a blocking member 52A. The blocking member 52A is a member for separating the edges by blocking the plurality of adhesive layers from each other. The blocking member 52A is located between the lower edge 33A of the first adhesive layer 31A and the upper edge 34A of the second adhesive layer 32A in the gap between the outer peripheral surface 37A of the rotor core 9A and the inner peripheral surface 38A of the permanent magnet 11A. It is located.

The blocking member 52A is integrated with the rotor core 9A. That is, the blocking member 52A protrudes toward the axial center 14 in the radial direction F1 from the intermediate portion in the axial direction A1 of the outer peripheral surface 37A of the rotor core 9 of the first embodiment.

In the sixth modification, the shielding member 52A facilitates the positioning of the first adhesive layer 31A and the second adhesive layer 32A, making it easier to manufacture the rotor 3A.

(Other variations)
In the first embodiment, the adhesive layers of all the permanent magnets are divided in the axial direction, but only some of the permanent magnets may have adhesive layers divided in the axial direction.

In the first and second embodiments, the edges of the two adhesive layers faced each other at a distance over the entire circumference, but if some parts of the adhesive layer faced each other at a distance, at least that portion In this case, the same effects as in the first embodiment can be obtained. Therefore, the edges may be partially connected in the circumferential direction.

Although the first embodiment and the second embodiment are directed to an inner rotor type electric motor, the present disclosure can also be applied to an outer rotor type electric motor.

By combining the first modification, the second modification, or the third modification, the blocking member may be used to realize three or more adhesive layers.

By combining the fourth modification, the fifth modification, or the sixth modification, the blocking member may be used to realize three or more adhesive layers.

The number and type of adhesive layers are not limited.

The number, position, and material of the blocking members are not limited.

The shape of the magnet placement hole and the magnet are not limited. In the first embodiment, the magnet arrangement hole extends long in the radial direction when viewed from above, but the magnet arrangement hole may extend substantially in the circumferential direction.

The rotor core may be a powder core whose main component is a powder material formed by pressure-molding a powdered magnetic material.

(mode)
The following aspects are disclosed herein.

The stator (3, 3A) according to the first aspect includes a rotor core (9, 9A), a permanent magnet (11, 11A), an adhesive (16, 16A, 40, 40A), and a rotating shaft (10 , 10A). The permanent magnets (11, 11A) are arranged close to the rotor core (9, 9A). The adhesive (16, 16A, 40, 40A) is placed between the rotor core (9, 9A) and the permanent magnet (11, 11A). 11A) is fixed. The rotating shaft (10, 10A) is fixed to the rotor core (9, 9A) and rotates around the shaft center (14). The adhesives (16, 16A, 40, 40A) are arranged in a line in the direction in which the axis (14) of the rotating shaft (10, 10A) extends, and are spaced apart from each other by opposing edges (33, 34). ) at least partially.

According to this aspect, strength saturation can be avoided by dividing the adhesive (16, 16A, 40, 40A) in the axial direction (A1). Thereby, even if the applied area of the adhesive (16, 16A, 40, 40A) is large, the adhesive strength per unit area does not decrease. As a result, even on rotor cores (9, 9A) that are long in the axial direction (A1), permanent magnets (11, 11A) can be bonded with strength corresponding to the bonding area.

The stator (3) according to the second aspect includes a plurality of permanent magnets (11) in the first aspect. The rotor core (9) has a plurality of magnet placement holes (13) arranged in the circumferential direction and corresponding to the plurality of permanent magnets (11). Each of the plurality of permanent magnets (11) is arranged inside a corresponding one of the plurality of magnet arrangement holes (13).

According to this aspect, even in the rotor core (9) that is long in the axial direction (A1), the permanent magnet (11) can be bonded to the magnet arrangement hole (13) with a strength that corresponds to the bonding area.

In the rotor (3, 3A) according to the third aspect, in the first or second aspect, the edges (33, 34) of the plurality of adhesive layers (31, 32) face each other at a distance.

According to this aspect, even in the rotor core (9, 9A) that is long in the axial direction (A1), the permanent magnets (11, 11A) are bonded to the magnet placement holes (13, 13A) with a strength that corresponds to the bonding area. It becomes possible.

In any one of the first to third aspects, the rotor (3, 3A) according to the fourth aspect has a plurality of It further includes a blocking member (51, 51A, 52, 52A) disposed between the edges (33, 33A, 34, 34A) of the adhesive layer (31, 31A, 32, 32A).

According to this aspect, the adhesive layer (31, 31A, 32, 32A) can be easily positioned by the blocking member (51, 51A, 52, 52A), so manufacturing of the rotor (3, 3A) is simplified. .

In the rotor (3, 3A) according to the fifth aspect, the blocking member (51, 51A) is fixed to the permanent magnet (11, 11A) in the fourth aspect.

According to this aspect, the adhesive layers (31, 31A, 32, 32A) can be easily positioned with respect to each other by the blocking member (51, 51A), so manufacturing of the rotor (3, 3A) is simplified.

In the rotor (3, 3A) according to the sixth aspect, the blocking member (52) is integrated with the rotor core (9, 9A) in the fourth aspect.

According to this aspect, the adhesive layer (31, 31A, 32, 32A) can be easily positioned by the blocking member (52, 52A), so manufacturing of the rotor (3, 3A) is simplified.

In any one of the first to sixth aspects, the rotor (3, 3A) according to the seventh aspect includes three or more adhesive layers (41, 41A, 42, 42A, 43, 43A, 44, 44A, 45, 45A).

According to this aspect, even on the rotor cores (9, 9A) that are long in the axial direction (A1), the permanent magnets (11, 11A) can be bonded with a strength corresponding to the bonding area.

The electric motor (1, 1A) according to the eighth aspect includes the rotor (3, 3A) and stator (2, 2A) in any one of the first to seventh aspects.

According to the rotor and motor of the present disclosure, the adhesive strength between the permanent magnet and the rotor core can be increased. Therefore, the rotor and electric motor of the present disclosure can improve the reliability of the electric motor and are industrially useful.

1, 1A: Electric motor 2, 2A:

Stator

3, 3A:

Rotor

9, 9A:

Rotor core

10, 10A: Rotating

shaft

11, 11A: Permanent magnet 13: Magnet placement hole 14:

Axis center

16, 16A, 40 , 40A: Adhesive 31, 31A, 41, 41A: First

adhesive layer

32, 32A, 42, 42A: Second adhesive layer 43, 43A: Third

adhesive layer

44, 44A: Fourth

adhesive layer

45, 45A: 5

adhesive layer

51, 51A: blocking

member

52, 52A: blocking member A1: axial direction C1: circumferential direction F1: radial direction

Claims

rotor core,
a permanent magnet disposed close to the rotor core;
an adhesive disposed between the rotor core and the permanent magnet to fix the rotor core and the permanent magnet;
a rotating shaft fixed to the rotor core and having the shaft center as the rotation center;
The adhesive has a plurality of adhesive layers arranged in a line in a direction in which the axial center of the rotating shaft extends, each having at least partially opposite edges at a distance from each other.
rotor.
comprising a plurality of the permanent magnets,
The rotor core has a plurality of magnet placement holes arranged in a circumferential direction and corresponding to the plurality of permanent magnets,
Each of the plurality of permanent magnets is arranged inside a corresponding magnet arrangement hole among the plurality of magnet arrangement holes,
A rotor according to claim 1.
The edges of the plurality of adhesive layers face each other at a distance,
The rotor according to claim 1 or 2.
further comprising a blocking member disposed between the edges of the plurality of adhesive layers between the rotor core and the permanent magnet;
The rotor according to any one of claims 1 to 3.
the blocking member is fixed to the permanent magnet;
A rotor according to claim 4.
the blocking member is integral with the rotor core;
A rotor according to claim 4.
The plurality of adhesive layers include three or more adhesive layers,
A rotor according to any one of claims 1 to 6.
A rotor according to any one of claims 1 to 7,
a stator;
Equipped with
Electric motor.