Rotor

Abstract

To solve the problem of a conventional rotor in which when a torque accompanied by rotation is applied, a force to rotate acts at each position on each magnet to generate stress concentration on an outer cylinder.SOLUTION: A rotor R has a structure in which a plurality of magnets 2 are disposed along the circumferential direction on an outer circumferential surface of a rotor shaft 1. Adjacent magnets 2 and 2 have a supportive surface S that intersects with the radial direction on at least one portion of their contact surface. The adjacent magnets 2 and 2 are formed with engaging portions 2A and 2B that overlap in the radial direction by the supportive surface S to allow a rotational force generated in each magnet 2 during rotation to be suppressed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a rotor used in a rotating electric machine such as a motor or a generator. [Background technology]

[0002] An example of a conventional rotor is described in Patent Document 1. Patent Document 1 discloses a rotor in which permanent magnets are arranged on the outer periphery of a shaft, a member with a lower density than the permanent magnets is arranged on the shaft axial side end of the permanent magnets, and a filament winding layer (outer cylinder) is formed on the outer surface side. This rotor prevents the permanent magnets from floating up without reducing the holding strength of the permanent magnets. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-111323 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional rotors such as those described above, when torque due to rotation is applied, a force acts on each magnet, causing it to rotate at its respective position (local rotation), and the corners of the magnets try to push up the outer cylinder, resulting in stress concentration on the outer cylinder.The challenge was to solve this problem.

[0005] The present invention has been made in consideration of the above-mentioned conventional situation, and aims to provide a rotor in which magnets (permanent magnets) are arranged on the outer periphery of a rotor shaft, capable of suppressing the rotational force generated in each magnet. [Means for solving the problem]

[0006] The rotor according to the present invention has a structure in which a plurality of magnets are arranged circumferentially around the outer circumferential surface of a rotor shaft, and is characterized in that adjacent magnets have support surfaces on at least a portion of their contact surfaces that intersect with the radial direction of the rotor shaft, and the support surfaces form engagement portions between adjacent magnets that overlap in the radial direction of the rotor shaft. Effect of the Invention

[0007] By adopting the above-described configuration, the rotor of the present invention has each magnet mechanically engaged with each other by the support surface and engagement portion, thereby making it possible to suppress the rotational force generated in each magnet when rotated. [Brief description of the drawings]

[0008] [Figure 1] 1 is a plan view showing a rotor according to a first embodiment of the present invention, with one side omitted. [Diagram 2] FIG. 4 is a plan view of a main portion showing a second embodiment of a rotor according to the present invention. [Diagram 3] FIG. 11 is a plan view showing a rotor according to a third embodiment of the present invention, with one side omitted. [Figure 4] FIG. 11 is a plan view showing a rotor according to a fourth embodiment of the present invention, with one side omitted. [Diagram 5] FIG. 13 is a plan view showing a rotor according to a fifth embodiment of the present invention, with one side omitted. [Figure 6] FIG. 2 is an explanatory diagram showing a Halbach array of magnets. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] First Embodiment 1, the lower half of which is omitted, has a structure in which a plurality of magnets (permanent magnets) 2 are arranged along the circumferential direction of the outer circumferential surface of a rotor shaft 1. In this rotor R, adjacent magnets 2, 2 have support surfaces S that intersect with the radial direction of the rotor shaft 1 on at least a portion of their contact surfaces. In addition, in the rotor R, engagement portions 2A, 2B that overlap in the radial direction of the rotor shaft 1 by the support surfaces S are formed between adjacent magnets 2, 2.

[0010] In the rotor R of this embodiment, each magnet 2 has, as engagement parts, an outer engagement part 2A arranged on the outer periphery side and protruding in one circumferential direction, and an inner engagement part 2B arranged on the inner periphery side and protruding in the other circumferential direction, and a support surface S is formed between the outer engagement part 2A and the inner engagement part 2B between adjacent magnets 2, 2.

[0011] Here, the abutment surfaces of adjacent magnets 2, 2 are basically parallel to the radial direction of the rotor shaft 1. In the rotor R of this embodiment, the abutment surfaces on both sides of the circumferential direction of each magnet 2 have support surfaces S located approximately in the center between the outer and inner circumferences, which intersect at right angles to the radial direction.

[0012] More specifically, each magnet 2 has, on one contact surface, which is the left side in Fig. 1, a stepped support surface S facing toward the center and an outer engagement portion 2A on its outer periphery, and, on the other contact surface, which is the right side in Fig. 1, a stepped support surface S facing semi-center and an inner engagement portion 2B on its inner periphery. Adjacent magnets 2, 2 are arranged such that the outer periphery engagement portion 2A and the inner periphery engagement portion 2B of the adjacent magnet overlap in the radial direction, as shown by the matte pattern applied to a portion in Fig. 1.

[0013] In this embodiment, each magnet 2 has the same shape, and in a more preferred embodiment, the position of the center of gravity in the radial direction of the rotor shaft 1 and the mass are the same. The rotor R in the illustrated example includes a cylindrical body 3 that holds the magnets 2 between itself and the rotor shaft 1. This cylindrical body 3 is made of, for example, plastic or fiber-reinforced plastic. The rotor R is combined with a stator (not shown) to constitute a rotating electric machine such as a motor or a generator.

[0014] The rotor R having the above configuration rotates counterclockwise as indicated by the arrow on the rotor shaft 1. At this time, in the rotor R, a local rotational force that tends to rotate counterclockwise is generated in each magnet 2 at each position as indicated by the arrow. In contrast, in the rotor R described above, as shown in the enlarged view in FIG. 1, a force toward the center (arrow A1) acts on the outer engagement portion 2A of the magnet 2, and a force toward the semi-center (arrow A2) acts on the inner engagement portion 2B of the same magnet, but similar forces (arrows A3, A4) also act on the adjacent magnets 2, 2 on both sides, so that the respective forces cancel each other out.

[0015] In this way, the magnets 2 of the rotor R are mechanically engaged with each other by the support surface S and the engagement portions 2A and 2B, and the rotational force generated in each magnet 2 during rotation can be suppressed. The rotor R can prevent the magnets 2 from shifting or floating, and also prevents damage to the cylindrical body 3 due to stress concentration.

[0016] Furthermore, since the rotor R includes the cylindrical body 3, in addition to the above effects, it can firmly hold each magnet 2. Furthermore, since the rotor R has the same center of gravity position and mass of each magnet 2, the centrifugal force acting on each magnet 2 is also the same, and the effect of suppressing the rotational force in each magnet 2 can be made uniform.

[0017] 2 to 6 are diagrams illustrating second to fifth embodiments of a rotor according to the present invention. In the following embodiments, the same reference numerals are given to the same parts as in the first embodiment, and detailed description thereof will be omitted.

[0018] <Second embodiment> The rotor R, the main part of which is shown in Fig. 2, has a configuration equivalent to that of the first embodiment, and has an adhesive 4 provided between the support surfaces S of each magnet 2. As with the previous embodiment, this rotor R can suppress the rotational force generated in each magnet 2 when rotated, and in particular, by providing the adhesive 4 between the support surfaces S, the holding force of each magnet 2 can be further improved. Note that providing an adhesive between the rotor shaft 1 and each magnet 2 of the rotor R is also effective in further improving the holding force.

[0019] <Third embodiment> 3, one of the magnets 2 has two inner engagement portions 2B, 2B arranged on the inner periphery side and protruding in both circumferential directions as engagement portions of two adjacent magnets. The other magnet 2 of the rotor R has outer engagement portions 2A, 2A arranged on the outer periphery side and protruding in both circumferential directions as engagement portions. The rotor R has a support surface S between the outer engagement portion 2A and the inner engagement portion 2B of the adjacent magnets 2, 2, which is perpendicular to the radial direction.

[0020] When the rotor R rotates counterclockwise, a local counterclockwise rotational force acts on each magnet 2, and as shown in the enlarged left view of Figure 3, on one side of the magnet 2, which is the left side of the figure, a central force (arrow A1) acts on the outer engagement portion 2A, while in response, a semi-central force (arrow A2) acts on the inner engagement portion 2B of the adjacent magnet 2, cancelling out the two forces.

[0021] In addition, when the rotor R rotates clockwise, as shown in the enlarged view in Figure 3, a clockwise local rotational force acts on each magnet 2, and on the other side of the magnet 2, which is the right side in the figure, a central force (arrow A1) acts on the outer engagement portion 2A, and a semi-central force (arrow A2) acts on the inner engagement portion 2B of the adjacent magnet 2, canceling out both forces.

[0022] The above rotor R can suppress the rotational force generated in each magnet 2 when rotating in the forward and reverse directions, and is therefore particularly useful for application to electric vehicle motors that recover regenerative energy, and can effectively suppress the required local rotational force of the magnet 2 in both the forward and reverse directions.

[0023] <Fourth embodiment> 4, each magnet 2 has, on one of its circumferential sides, an outer engagement portion 2A and an inner engagement portion 2B that are spaced apart from each other on the outer and inner sides and protrude in one circumferential direction, and an intermediate engagement portion 2C that is located halfway between the outer and inner circumferences and protrudes in the other circumferential direction, on the other side. The rotor R has step-shaped support surfaces S that are perpendicular to the radial direction between the outer engagement portion 2A and the intermediate engagement portion 2C, and between the intermediate engagement portion 2C and the inner engagement portion 2B, between adjacent magnets 2, 2.

[0024] As with the third embodiment, the rotor R described above can also suppress the rotational force generated in each magnet 2 during forward and reverse rotation, making it particularly useful for application to motors for electric vehicles that recover regenerative energy using the motor, and can effectively suppress the local rotational force of each magnet 2.

[0025] <Fifth embodiment> The rotor R shown in Fig. 5 has a basic configuration similar to that of the third embodiment (see Fig. 3). In the rotor R of this embodiment, the magnet 2 having the two inner engagement portions 2B, 2B has a magnetic orientation in the radial direction of the rotor shaft 1, and the magnet 2 having the two outer engagement portions 2A, 2A has a magnetic orientation in the tangential direction of the rotor shaft 1.

[0026] That is, the rotor R in this embodiment has magnets 2 with radial magnetic orientation and magnets 2 with tangential magnetic orientation arranged alternately in the circumferential direction. Also, the magnets 2 in the rotor R are arranged so that the directions of the magnetic orientations (S → N) of every other magnet 2, 2 are different.

[0027] In the rotor R having the above-mentioned configuration, the magnet 2 having a magnetic orientation in the rotor radial direction repels the surrounding magnets 2 and tends to jump out of the rotor R. However, by forming the magnet 2 to have an inner engagement portion 2B, the rotational force generated in the magnet 2 can be suppressed, and furthermore, this is extremely effective for application to an electric vehicle motor that recovers regenerative energy by the motor.

[0028] Moreover, the rotor R described above can obtain the same effect as the magnets in the Halbach array shown in Fig. 6. The Halbach array maximizes the magnetic field strength in a specific direction by alternating the direction of the magnetic poles of each magnet. That is, the rotor R of the embodiment shown in Fig. 5 can maximize the magnetic field strength in its semi-center direction (stator direction), and can actively suppress only magnets that are particularly tilted by magnetic force, thereby reducing stress concentration in the cylinder 3 and the adhesive provided between the parts.

[0029] The specific configuration of the rotor according to the present invention is not limited to the above-mentioned embodiments, and may be appropriately changed without departing from the scope of the present invention. For example, the magnets of the rotor R may be either symmetrical or asymmetrical. Furthermore, since the support surface is at least a part of the joint surface, it may be, for example, a surface inclined with respect to the radial direction of the rotor shaft, that is, the entire contact surface. However, if the support surface is a stepped surface facing toward the center or semi-center as described in each embodiment, it is more effective in suppressing the local rotational force. [Explanation of symbols]

[0030] R rotor S support surface 1 rotor shaft 2. Magnets 2A Outer engaging part 2B Inner engaging part 2C Intermediate engagement part 3. Cylinder 4. Glue

Claims

1. A rotor having a structure in which a plurality of magnets are arranged along the circumferential direction of the outer circumferential surface of a rotor shaft, Adjacent magnets have support surfaces on at least a portion of their contact surfaces that intersect with the radial direction of the rotor shaft, A rotor characterized in that adjacent magnets have engagement portions formed by the support surfaces so as to overlap in the radial direction of the rotor shaft.

2. Each of the magnets has, as the engaging portion, an outer engaging portion disposed on the outer circumferential side and protruding in one circumferential direction, and an inner engaging portion disposed on the inner circumferential side and protruding in the other circumferential direction, 2. The rotor according to claim 1, wherein the support surface is formed between the outer engaging portion and the inner engaging portion of each of the adjacent magnets.

3. One of the two adjacent magnets has, as the engagement portion, two inner engagement portions that are arranged on the inner circumferential side and protrude in both circumferential directions, The other magnet has, as the engaging portion, the outer engaging portion that is disposed on the outer circumferential side and protrudes in both circumferential directions, 2. The rotor according to claim 1, wherein the support surface is formed between the outer engaging portion and the inner engaging portion of each of the adjacent magnets.

4. The magnet having the two inner engagement portions has a magnetic orientation in a radial direction of the rotor shaft, 4. The rotor of claim 3, wherein the magnets having two of the outer engagement portions have a magnetic orientation tangential to the rotor shaft.

5. The magnets each have, as the engaging portion, an outer engaging portion and an inner engaging portion that are arranged at an outer circumferential side and an inner circumferential side and spaced apart from each other and protrude in one circumferential direction; an intermediate engagement portion disposed between the outer periphery and the inner periphery and protruding in the other circumferential direction; 2. The rotor according to claim 1, wherein the support surfaces are formed between the outer engagement portion and the intermediate engagement portion, and between the intermediate engagement portion and the inner engagement portion, for adjacent magnets.

6. 6. The rotor according to claim 1, wherein an adhesive is provided between the support surfaces of adjacent magnets.

7. 2. The rotor according to claim 1, further comprising a cylindrical body for holding the magnet between the rotor shaft and the cylindrical body.

8. 2. The rotor according to claim 1, wherein each of the magnets has a mass equivalent to a center of gravity position in a radial direction of the rotor shaft.

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