Rotor and rotor manufacturing method

Abstract

A rotor (10) comprises: an annular magnet portion (22) in which a plurality of permanent magnets (31) are annularly disposed along the circumferential direction; and a scattering prevention member (23) that covers the outer circumferential surface (22a) of the annular magnet portion over the entire circumference. The scattering prevention member is formed by spirally winding a sheet material (51) made of a fiber-reinforced resin material around a winding range (Aw) including at least the entire outer circumferential surface of the annular magnet portion, the fiber-reinforced resin material being obtained by solidifying a fiber bundle (52) with a resin base material (53). The scattering prevention member includes: a plurality of layers (X1 to X7) that are formed continuously from one sheet material and overlap in the radial direction; and transition portions (61-66) that is a part of the sheet material and located between adjacent layers of the plurality of layers. Each of the plurality of layers is formed by spirally winding the sheet material around the winding range about an axis (L1) of the rotor. The transition portions have a straight portion (70) that is positioned at ends (E1, E2) of the winding range in the axial direction and extends along a plane surface perpendicular to the axis.

Description

Rotor and method of manufacturing the rotor CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Application No. 2023-208747, filed on December 11, 2023, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a rotor in a motor and a method for manufacturing the rotor.

[0003] For example, the rotor described in Patent Document 1 includes an annular magnet portion having multiple permanent magnets arranged in a circular pattern along the circumferential direction, and a shatterproof member covering the entire outer periphery of the annular magnet portion. The shatterproof member is formed of a fiber-reinforced resin material formed by solidifying fiber bundles with a resin base material. To form the shatterproof member, a first layer is formed by spirally winding a sheet material in which fiber bundles are impregnated with the resin base material around the outer periphery of the annular magnet portion. Then, a second layer is formed by spirally winding a sheet material on the outer periphery of the first layer. After forming multiple layers using the sheet material in this manner, the multiple layers are heated to melt and harden the resin base material of the sheet material. This results in a cylindrical shatterproof member being formed around the outer periphery of the annular magnet portion.

[0004] Patent No. 6969988

[0005] In the rotor described above, it is conceivable to continuously wind multiple layers of the shatterproof member from a single sheet material. In this case, if the spiral angle of the sheet material changes suddenly at the transition between adjacent layers, wrinkles will occur in the sheet material. If wrinkles occur in the sheet material, the effectiveness of the shatterproof member in fixing the annular magnet portion may be reduced.

[0006] An object of the present disclosure is to provide a rotor and a method for manufacturing the rotor that can suppress the occurrence of wrinkles in the sheet material at the transition portions between adjacent layers in the shatterproof member.

[0007] In a first aspect of the present disclosure, a rotor includes an annular magnet portion formed by a plurality of permanent magnets arranged in a ring shape along the circumferential direction, and a shatter prevention member covering the entire outer circumferential surface of the annular magnet portion, wherein the shatter prevention member is formed by spirally winding a sheet material made of a fiber-reinforced resin material formed by solidifying fiber bundles with a resin base material around a winding range that includes at least the entire outer circumferential surface of the annular magnet portion, and the shatter prevention member includes a plurality of layers formed continuously from the single sheet material and overlapping in the radial direction, and a transition portion between adjacent layers that is a part of the sheet material, and each of the plurality of layers is formed by spirally winding the sheet material around the axis of the rotor around the winding range, and the transition portion has a straight portion that is located at an axial end of the winding range and extends along a plane perpendicular to the axis.

[0008] According to this configuration, by providing a straight portion at the transition between adjacent layers in the sheet material forming the shatterproof member, it is possible to prevent the spiral angle of the sheet material from changing suddenly at the transition, thereby preventing wrinkles from occurring in the sheet material at the transition, and as a result, it is possible to prevent a decrease in the fixing effect of the annular magnet portion by the shatterproof member.

[0009] In a second aspect of the present disclosure, a method for manufacturing a rotor includes: an annular magnet portion formed by arranging a plurality of permanent magnets in a ring shape along the circumferential direction; and a shatter prevention member covering the entire outer circumferential surface of the annular magnet portion, wherein the shatter prevention member is formed by spirally winding a sheet material made of a fiber-reinforced resin material formed by solidifying fiber bundles with a resin base material, around a winding range that includes at least the entire outer circumferential surface of the annular magnet portion; and the shatter prevention member includes a plurality of layers formed continuously from the single sheet material and overlapping in the radial direction, and a transition portion between adjacent layers that is a part of the sheet material, wherein each of the plurality of layers is formed by spirally winding the sheet material around the axis of the rotor around the winding range; and the transition portion has a straight portion that is located at an axial end of the winding range and extends along a plane perpendicular to the axis.

[0010] According to this manufacturing method, by providing a straight section at the transition between adjacent layers in the sheet material forming the shatterproof member, it is possible to prevent the spiral angle of the sheet material from changing suddenly at the transition section, thereby preventing wrinkles from occurring in the sheet material at the transition section and, as a result, preventing a decrease in the fixing effect of the annular magnet portion by the shatterproof member.

[0011] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which Fig. 1 is a perspective view of a rotor according to one embodiment, Fig. 2 is a perspective view showing a manufacturing process for the rotor according to the same embodiment, Fig. 3 is a schematic perspective view showing the winding range of the sheet material according to the same embodiment, Fig. 4 is an explanatory diagram for explaining the winding mode of the sheet material according to the same embodiment, Fig. 5 is a schematic view showing a transition portion of the sheet material according to the same embodiment, Fig. 6 is an explanatory diagram for explaining the winding mode of the sheet material according to the same embodiment, and Fig. 7 is an explanatory diagram for explaining the winding mode of the sheet material according to a modified example.

[0012] An embodiment of a rotor and a method for manufacturing the rotor will now be described. A rotor 10 according to this embodiment, shown in FIG. 1, is one of the components constituting a motor. The rotor 10 is rotatably disposed on the inner periphery of a stator (not shown) that is configured in a substantially annular shape. The stator generates a rotating magnetic field for driving the rotor 10 to rotate when current is applied to its coil magnetic poles. The rotor 10 according to this embodiment is intended for use in a high-speed motor with a maximum operating speed of 12,000 rpm or more, for example.

[0013] (Configuration of Rotor 10) As shown in FIGS. 1 and 2, the rotor 10 of this embodiment includes a rotor base 21, an annular magnet portion 22, and a scattering prevention member 23.

[0014] The rotor base 21 is generally cylindrical and has a hollow structure for weight reduction, etc. One axial end of the rotor base 21 is integrally formed as an output shaft 21x.

[0015] (Configuration of the annular magnet portion 22) The outer peripheral surface of the rotor base 21 holds the cylindrical annular magnet portion 22 centered on the axis L1 of the rotor 10. The annular magnet portion 22 is a permanent magnet group consisting of multiple permanent magnets 31 arranged in a ring shape along the circumferential direction. Each permanent magnet 31 forming the annular magnet portion 22 has, for example, a substantially rectangular shape. The outer peripheral surface 22a of the annular magnet portion 22 is formed by the radially outer surface 31a of each permanent magnet 31. When viewed from the axial direction, the outer peripheral surface 22a of the annular magnet portion 22 forms a circle centered on the axis L1. The outer diameter of the annular magnet portion 22 is uniform throughout the axial direction of the annular magnet portion 22. The inner surface of each permanent magnet 31 abuts against the outer peripheral surface of the rotor base 21. Furthermore, the side end surfaces 31b on both sides of each permanent magnet 31 in the circumferential direction of the rotor 10 abut against the side end surfaces 31b of adjacent permanent magnets 31. The outer peripheral surface 22 a of the annular magnet portion 22 is covered over the entire periphery with a scattering prevention member 23 .

[0016] (Configuration of the Anti-Scattering Member 23) The anti-scattering member 23 that constitutes the rotor 10 has a generally cylindrical shape centered on the axis L1. The anti-scattering member 23 covers the entire circumferential surface 22a of the annular magnet portion 22. The axial length of the anti-scattering member 23 is set to be equal to or longer than the axial length of the annular magnet portion 22.

[0017] (Regarding the Forming of the Shatterproof Member 23) As shown in FIG. 2 , the shatterproof member 23 is formed by winding a sheet material 51 multiple times around a portion of the rotor 10, including the outer circumferential surface 22 a of the annular magnet portion 22. The sheet material 51 is a sheet-like material in which fiber bundles 52 are impregnated with a resin substrate 53. For example, a carbon fiber reinforced plastic (CFRP) material is used for the sheet material 51. When a carbon fiber reinforced plastic material is used for the sheet material 51, the fiber bundles 52 are made of carbon fiber. The resin substrate 53 is made of a thermosetting resin, for example. In this embodiment, the sheet material 51 has a volume content of the fiber bundles 52 of, for example, 60 to 70%. After being wound multiple times around the outer circumferential surface 22 a of the annular magnet portion 22, the sheet material 51 is heated to melt and harden. As a result, a substantially cylindrical shatterproof member 23 is formed on the outer circumferential surface 22 a of the annular magnet portion 22.

[0018] (Method for Manufacturing the Rotor 10) Next, a method for manufacturing the rotor 10 will be described along with the operation of this embodiment. First, a plurality of permanent magnets 31 are arranged along the circumferential direction on the outer circumferential surface of the rotor base 21. This forms the annular magnet portion 22 made up of the plurality of permanent magnets 31.

[0019] Next, the sheet material 51 is wound around the rotor 10 in a winding range Aw. For ease of explanation, FIG. 3 shows the winding range Aw of the rotor 10 as a cylindrical outer surface. In this embodiment, for example, the sheet material 51 is wound around the outer surface 22a of the annular magnet portion 22 from one axial end to the other. In this embodiment, the winding range Aw corresponds to the entire outer surface 22a of the annular magnet portion 22. In the following description, both axial ends of the winding range Aw are referred to as a first end E1 and a second end E2, respectively. Furthermore, in the following description, eight locations in the winding range Aw, which are set at equal intervals around the axis L1, are referred to as a first position P1, a second position P2, a third position P3, a fourth position P4, a fifth position P5, a sixth position P6, a seventh position P7, and an eighth position P8, in that order. The first position P1 to the eighth position P8 are set at 45-degree intervals around the circumferential direction. FIG. 4 is a schematic development view of the sheet material 51 spirally wound in the winding range Aw.

[0020] The shatterproof member 23 is formed by winding a single sheet material 51 in multiple layers. First, a first layer X1 is formed, which is the innermost layer of the shatterproof member 23 and contacts the outer peripheral surface 22a of the annular magnet portion 22. When forming the first layer X1, the sheet material 51 is spirally wound, for example, from a first end E1 to a second end E2 of the winding range Aw. As shown in FIG. 4 , when forming the first layer X1, a winding start portion 60 of the sheet material 51 is set at a first position P1 at the first end E1 of the winding range Aw. The winding start portion 60 is, for example, an end of the sheet material 51 in the longitudinal direction.

[0021] The first layer X1 begins at a first position P1 at the first end E1 and is wound spirally toward the second end E2 at a first helical angle θ1 for multiple turns. The number of turns is determined by the axial length of the winding range Aw, the diameter of the winding range Aw, the first helical angle θ1, the width of the sheet material 51, and other factors. The winding end position of the first layer X1 is set to a third position P3 at the second end E2 of the winding range Aw. Note that in each layer (first layer X1 to seventh layer X7) of the shatterproof member 23, including the first layer X1, the sheet material 51 is wound spirally so that, for example, a gap S (see FIG. 2) is formed between adjacent sheets of sheet material 51 in the axial direction. The first layer X1 to seventh layer X7 overlap radially.

[0022] Next, starting from the end of the first layer X1, the second layer X2 is wound using the same sheet material 51 as the sheet material 51 used to form the first layer X1. The winding directions of the first layer X1 and the second layer X2 are the same (e.g., both clockwise). The portion of the sheet material 51 where the first layer X1 transitions to the second layer X2 is designated as a first transition portion 61. The first transition portion 61 is the end of the winding of the first layer X1 and the beginning of the winding of the second layer X2. That is, the position of the first transition portion 61 is set to a third position P3 at the second end E2 of the winding range Aw. The second layer X2 is wound spirally toward the first end E1 for multiple turns at a second helical angle θ2, starting from the position of the first transition portion 61, i.e., the third position P3 at the second end E2. Note that FIG. 2 illustrates the second layer X2 in the middle of being wound.

[0023] As shown in Figure 5, the first transition section 61 has a straight portion 70 that extends along a plane perpendicular to the axis L1 of the rotor 10. When the rotor 10 is viewed from the radially outer side in a direction perpendicular to the axis L1, the straight portion 70 has a linear shape perpendicular to the axis L1. In other words, unlike the portion where the sheet material 51 is wound spirally, the straight portion 70 is not inclined with respect to the axial direction. Note that when viewed from the axial direction, the straight portion 70 has a curved shape that follows the outer peripheral surface 22a of the annular magnet portion 22.

[0024] The straight portion 70 is provided at the boundary between the first layer X1 and the second layer X2. That is, in the first transition portion 61, the first layer X1 having the first helical angle θ1 transitions through the straight portion 70 with no inclination angle relative to the axial direction to the second layer X2 having the second helical angle θ2. The inclusion of the straight portion 70 in the first transition portion 61 thus makes it possible to suppress abrupt deformation of the sheet material 51 in the first transition portion 61. Note that, in this embodiment, the second helical angle θ2 is set to an angle symmetrical with respect to the first helical angle θ1, for example. That is, when the first helical angle θ1 is set to a positive value and the second helical angle θ2 is set to a negative value, the absolute values ​​of the first helical angle θ1 and the second helical angle θ2 are the same. The straight portion 70 in the first transition portion 61 is formed at a third position P3 in the circumferential direction of the winding range Aw. Specifically, the circumferential position of the straight portion 70 is set so that the circumferential center C1 of the straight portion 70 coincides with the third position P3.

[0025] As shown in Figure 4, the winding of the second layer X2, which starts from the first transition portion 61, ends at a fifth position P5 at the first end E1 in the winding range Aw. A second transition portion 62 similar to the first transition portion 61 is formed at the fifth position P5. That is, the second layer X2 transitions to the third layer X3 via the second transition portion 62. The second transition portion 62 has a straight portion 70 similar to the first transition portion 61.

[0026] The third layer X3 starts winding at the second transition portion 62, i.e., at a fifth position P5 at the first end E1, and is wound spirally toward the second end E2 at a third helical angle θ3 for multiple turns. The third helical angle θ3 is set to, for example, the same angle as the first helical angle θ1. The winding end of the third layer X3 is set to a seventh position P7 at the second end E2 of the winding range Aw.

[0027] The shatterproof member 23 of this embodiment is formed up to the seventh layer X7 by repeatedly winding one sheet material 51 as described above. When winding the first layer X1 to the seventh layer X7 using the sheet material 51, tension is applied to the sheet material 51 in the longitudinal direction.

[0028] The third layer X3 transitions to the fourth layer X4 via a third transition portion 63 at a second end E2 of the winding range Aw. The circumferential position of the third transition portion 63 is set to a seventh position P7. The fourth layer X4 transitions to the fifth layer X5 via a fourth transition portion 64 at a first end E1 of the winding range Aw. The circumferential position of the fourth transition portion 64 is set to a first position P1.

[0029] The fifth layer X5 transitions to the sixth layer X6 via a fifth transition portion 65 at a second end E2 of the winding range Aw. The circumferential position of the fifth transition portion 65 is set to a third position P3. The sixth layer X6 transitions to the seventh layer X7 via a sixth transition portion 66 at a first end E1 of the winding range Aw. The circumferential position of the sixth transition portion 66 is set to a fifth position P5. Each of the first transition portion 61 to the sixth transition portion 66 has a straight portion 70.

[0030] The seventh layer X7 begins winding at the sixth transition portion 66 and is wound spirally toward the second end E2 for multiple turns. The winding end of the seventh layer X7 is set to a seventh position P7 at the second end E2 of the winding range Aw. The winding end of the seventh layer X7 is, for example, the winding end portion 67 of the sheet material 51. The winding end portion 67 is the end opposite the winding start portion 60 of one sheet material 51 that forms the shatterproof member 23.

[0031] As described above, in the shatterproof member 23 of this embodiment, the winding end positions of each of the first layer X1 to seventh layer X7 are offset by 90° in the circumferential direction. Furthermore, in each of the first layer X1 to seventh layer X7, the ends on both axial sides of the winding range Aw, i.e., the winding start and winding end, are referred to as layer ends. The layer ends on both axial sides of the first layer X1 are the winding start portion 60 and the first transition portion 61. The layer ends on both axial sides of the second layer X2 are the first transition portion 61 and the second transition portion 62. The layer ends on both axial sides of the third layer X3 are the second transition portion 62 and the third transition portion 63. The layer ends on both axial sides of the fourth layer X4 are the third transition portion 63 and the fourth transition portion 64. The layer ends on both axial sides of the fifth layer X5 are the fourth transition portion 64 and the fifth transition portion 65. The layer ends on both axial sides of the sixth layer X6 are a fifth transition portion 65 and a sixth transition portion 66. The layer ends on both axial sides of the seventh layer X7 are the sixth transition portion 66 and a winding end portion 67 of the sheet material 51.

[0032] In the shatterproof member 23 formed by winding the sheet material 51 as described above, the layer ends of each of the first layer X1 to the seventh layer X7 are positioned at equal intervals in the circumferential direction at the first end E1 and the second end E2 in the winding range Aw.

[0033] Specifically, at the first end E1 of the winding range Aw, the winding start portion 60 and the fourth transition portion 64 are located at a first position P1, and the second transition portion 62 and the sixth transition portion 66 are located at a fifth position P5 that is 180° opposite in the circumferential direction from the first position P1. In other words, the winding start portion 60, the second transition portion 62, the fourth transition portion 64, and the sixth transition portion 66 are located at positions that are 180° apart at the first end E1 of the winding range Aw.

[0034] At the second end E2 of the winding range Aw, the first transition portion 61 and the fifth transition portion 65 are located at a third position P3, and the third transition portion 63 and the winding end portion 67 are located at a seventh position P7 that is 180° opposite in the circumferential direction from the third position P3. That is, the first transition portion 61, the third transition portion 63, the fifth transition portion 65, and the winding end portion 67 are arranged at positions that are 180° apart at the second end E2 of the winding range Aw.

[0035] When viewed across the entire winding range Aw, the layer ends of the first layer X1 to the seventh layer X7, i.e., the winding start portion 60, the first transition portion 61 to the sixth transition portion 66, and the winding end portion 67, are arranged at 90° intervals in the circumferential direction of the winding range Aw. The same number of layer ends (two in this embodiment) are arranged at each of the positions (first position P1, third position P3, fifth position P5, and seventh position P7) that are 90° apart in the circumferential direction of the winding range Aw.

[0036] In this embodiment, the helical angles of the sheet material 51 relative to the axis L1 of the rotor 10 are set to be equal in the Nth and (N+2)th layers of the shatterproof member 23. Specifically, the first helical angle θ1 in the first layer X1, the third helical angle θ3 in the third layer X3, the fifth helical angle θ5 in the fifth layer X5, and the seventh helical angle θ7 in the seventh layer X7 are set to be equal to each other. Also, the second helical angle θ2 in the second layer X2, the fourth helical angle θ4 in the fourth layer X4, and the sixth helical angle θ6 in the sixth layer X6 are set to be equal to each other.

[0037] Furthermore, the start positions of the spiral winding are offset in the circumferential direction between the Nth layer and the (N+2)th layer. As a result, as shown in FIG. 6 , for example, although the helical angles (first helical angle θ1 and third helical angle θ3) are the same between the first layer X1 and the third layer X3, the positions of the sheet material 51 forming the layers are offset in the axial direction between the first layer X1 and the third layer X3. As a result, the positions of the gaps S in the first layer X1 and the third layer X3 do not coincide with each other. This results in a configuration in which the outer peripheral surface 22 a of the annular magnet portion 22 is less likely to be exposed radially outward through the gaps S.

[0038] After the first layer X1 to the seventh layer X7 are wound around the sheet material 51 as described above, a heating step is carried out in which the sheet material 51 is heated to melt and harden the resin base material 53. As a result, the resin base material 53 is fused and hardened integrally to form a cylindrical shatter prevention member 23 on the outer periphery of the annular magnet portion 22. Note that in this heating step, it is preferable to heat the sheet material 51 while maintaining a state in which tension is applied to the sheet material 51 using a jig (not shown) or the like.

[0039] (Effects of the Present Embodiment) The operation of the present embodiment will be described below. (1) Each of the multiple transition sections (first transition section 61 to sixth transition section 66) included in the shatterproof member 23 has a straight section 70. The straight section 70 is located at the axial end (first end section E1 or second end section E2) of the winding range Aw and extends along a plane perpendicular to the axis L1. With this configuration, providing the straight section 70 in each of the first transition section 61 to sixth transition section 66 can prevent the spiral angle of the sheet material 51 from changing suddenly in each of the first transition section 61 to sixth transition section 66. Therefore, it is possible to prevent wrinkles from occurring in the sheet material 51 in each of the first transition section 61 to sixth transition section 66, and as a result, it is possible to prevent a decrease in the fixing effect of the annular magnet section 22 by the shatterproof member 23.

[0040] (2) The shatterproof member 23 includes layer end portions, which are the axial ends of each of the first through seventh layers X1 through X7. These layer end portions include the winding start portion 60 of the sheet material 51, the winding end portion 67 of the sheet material 51, and the first through sixth transition portions 61 through 66. The same number (two) of layer end portions are provided at each of the equally spaced positions (the first position P1, the third position P3, the fifth position P5, and the seventh position P7) in the circumferential direction of the winding range Aw. This configuration allows the layer end portions (the winding start portion 60, the first through sixth transition portions 61 through 66, and the winding end portion 67) included in the shatterproof member 23 to be balanced in the circumferential direction. This prevents the occurrence of weight imbalance in the circumferential direction of the shatterproof member 23. As a result, it is possible to suppress the occurrence of vibrations and the like during rotation of the rotor 10.

[0041] (3) In each of the first layer X1 to the seventh layer X7, the sheet material 51 is spirally wound such that a gap S is formed between adjacent sheet materials 51 in the axial direction. With this configuration, when the sheet material 51 is spirally wound, it is possible to prevent adjacent sheet materials 51 from partially overlapping each other in the axial direction. This prevents the adjacent sheet materials 51 from partially overlapping each other in the axial direction, thereby preventing portions from protruding radially outward, and makes it possible to make the outer diameter of the shatterproof member 23 uniform.

[0042] (4) In the Nth layer and the (N+2)th layer of the multiple layers (first layer X1 to seventh layer X7) of the shatterproof member 23, the helical angle of the sheet material 51 relative to the axis L1 is the same, and the positions of the layer ends are offset in the circumferential direction. With this configuration, while the helical angle is the same in the Nth layer and the (N+2)th layer, the positions of the sheet material 51 forming the layers are offset in the axial direction in the Nth layer and the (N+2)th layer. As a result, the positions of the gaps S do not match in the Nth layer and the (N+2)th layer, making it difficult for the outer peripheral surface 22a of the annular magnet portion 22 to be exposed radially outward from the gaps S.

[0043] (Other Embodiments) The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other within the scope of technical compatibility.

[0044] The arrangement of the layer ends (the winding start portion 60, the first transition portion 61 to the sixth transition portion 66, and the winding end portion 67) in the shatterproof member 23 is not limited to the above embodiment, and may be changed to, for example, the configuration shown in Figure 7.

[0045] In the configuration shown in Figure 7, layer ends are arranged at 45° intervals in the circumferential direction of the winding range Aw. Specifically, the winding start portion 60 of the first layer X1 is set at a first position P1 at the first end E1 of the winding range Aw. The first transition portion 61 between the first layer X1 and the second layer X2 is set at a second position P2 at the second end E2 of the winding range Aw. The second transition portion 62 between the second layer X2 and the third layer X3 is set at a third position P3 at the first end E1 of the winding range Aw. The third transition portion 63 between the third layer X3 and the fourth layer X4 is set at a fourth position P4 at the second end E2 of the winding range Aw. The fourth transition portion 64 between the fourth layer X4 and the fifth layer X5 is set at a fifth position P5 at the first end E1 of the winding range Aw. The fifth transitional portion 65 between the fifth layer X5 and the sixth layer X6 is located at a sixth position P6 at the second end E2 of the winding range Aw. The sixth transitional portion 66 between the sixth layer X6 and the seventh layer X7 is located at a seventh position P7 at the first end E1 of the winding range Aw. The winding end portion 67 of the seventh layer X7 is located at an eighth position P8 at the second end E2 of the winding range Aw. Even with this configuration, the same number (one) of layer end portions are provided at positions (the first position P1 to the eighth position P8) that are equally spaced circumferentially of the winding range Aw, allowing the layer end portions included in the shatterproof member 23 to be well-balanced in the circumferential direction. This makes it possible to prevent weight imbalance in the circumferential direction of the shatterproof member 23.

[0046] The helical angles of the sheet material 51 relative to the axis L1 may be different between the Nth layer and the (N+2)th layer among the multiple layers (first layer X1 to seventh layer X7) of the shatterproof member 23. For example, in the case of the first layer X1 and the third layer X3, the first helical angle θ1 and the third helical angle θ3 may be set to different angles.

[0047] The shatterproof member 23 may be wound so that the axial end faces of adjacent sheet materials 51 in the axial direction are in contact with each other in all or some of the first layer X1 to seventh layer X7. The shatterproof member 23 may also be wound so that the axial end faces of adjacent sheet materials 51 in the axial direction are overlapped with each other in all or some of the first layer X1 to seventh layer X7.

[0048] The number of layers formed successively from a single sheet material 51 in the shatterproof member 23 is not limited to that in the above embodiment, but may be any number from two to six, or eight or more. Note that by changing the number of layers in the shatterproof member 23, the number of transitions between adjacent layers also changes.

[0049] The winding range Aw of the sheet material 51 is not limited to a configuration including only the outer peripheral surface 22 a of the annular magnet portion 22 , and may be set to a range including other than the annular magnet portion 22 , for example, a part of the rotor base portion 21 .

[0050] In the rotor 10 of the above embodiment, the fiber bundles 52 included in the sheet material 51 may be changed to fibers other than carbon fiber. Additionally, the configuration of the rotor 10 may be changed as appropriate. Furthermore, the shape of the rotor base 21 may be changed as appropriate.

[0051] In the above embodiment, the rotor 10 and the stator are radially opposed to each other, but the present invention may be applied to an axial type in which the rotor and the stator are axially opposed to each other.

[0052] While the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to the embodiments or structures. The present disclosure also encompasses various modifications and modifications within the scope of equivalents. In addition, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure.

[0053] (Note) The features of the present disclosure are as follows: [1] A rotor (10) including an annular magnet portion (22) in which a plurality of permanent magnets (31) are arranged annularly in the circumferential direction, and a scattering prevention member (23) covering the entire outer circumferential surface (22a) of the annular magnet portion, wherein the scattering prevention member is formed by spirally winding a sheet material (51) made of a fiber-reinforced resin material obtained by solidifying a fiber bundle (52) with a resin base material (53) in a winding range (Aw) that includes at least the entire outer circumferential surface of the annular magnet portion, and ... and a transition section (61-66) between adjacent layers of the plurality of layers, the transition section being a part of the sheet material, wherein each of the plurality of layers is formed by spirally winding the sheet material within the winding range around an axis (L1) of the rotor, and the transition section has a straight section (70) located at an end (E1, E2) in the axial direction of the winding range and extending along a plane perpendicular to the axis.

[0054] [2] The rotor described in [1] above, wherein the anti-scattering member includes layer ends (60, 61 to 66, 67) which are axial ends of each of the plurality of layers, and the layer ends include a winding start portion (60) of the sheet material, a winding end portion (67) of the sheet material, and the transition portion, and the same number of layer ends are provided at equally spaced positions in the circumferential direction of the winding range.

[0055] [3] A rotor as described in [1] or [2] above, wherein in each of the plurality of layers, the sheet material is spirally wound so that a gap (S) is formed between adjacent sheets of sheet material in the axial direction.

[0056] [4] The rotor described in [3] above, wherein the anti-scattering member includes layer ends (60, 61 to 66, 67) which are the axial ends of each of the plurality of layers, and when the innermost layer of the plurality of layers is numbered 1, the helical angles of the sheet material with respect to the axis are equal in the Nth layer and the (N+2)th layer, and the positions of the layer ends are shifted circumferentially.

[0057] [5] A method for manufacturing a rotor (10) including an annular magnet portion (22) in which a plurality of permanent magnets (31) are arranged annularly along the circumferential direction, and a scattering prevention member (23) covering the entire outer circumferential surface (22a) of the annular magnet portion, wherein the scattering prevention member is formed by spirally winding a sheet material (51) made of a fiber-reinforced resin material obtained by solidifying a fiber bundle (52) with a resin base material (53) in a winding range (Aw) that includes at least the entire outer circumferential surface of the annular magnet portion, and the scattering prevention member is formed by spirally winding a sheet material (51) made of a fiber-reinforced resin material obtained by solidifying a fiber bundle (52) with a resin base material (53) in a winding range (Aw) that includes at least the entire outer circumferential surface of the annular magnet portion, and a transition portion (61-66) that is a portion of the sheet material and between adjacent layers in the plurality of layers, each of the plurality of layers being formed by spirally winding the sheet material within the winding range around an axis (L1) of the rotor, and the transition portion has a straight portion (70) that is located at an end (E1, E2) in the axial direction of the winding range and extends along a plane perpendicular to the axis.

Claims

1. A rotor (10) comprising: an annular magnet portion (22) in which a plurality of permanent magnets (31) are arranged in an annular shape along the circumferential direction; and a shatterproof member (23) covering the entire outer circumferential surface (22a) of the annular magnet portion, wherein the shatterproof member is formed by spirally winding a sheet material (51) made of a fiber-reinforced resin material obtained by solidifying a fiber bundle (52) with a resin base material (53) in a winding range (Aw) including at least the entire outer circumferential surface of the annular magnet portion, and the shatterproof member includes a plurality of layers (X1 to X7) formed continuously from one of the sheet material and overlapping in the radial direction, and transition portions (61 to 66) between adjacent layers in the plurality of layers, which are portions of the sheet material, and each of the plurality of layers is formed by spirally winding the sheet material in the winding range around the axis (L1) of the rotor, The transition portion has a straight portion (70) located at an axial end (E1, E2) of the winding range and extending along a plane perpendicular to the axis.

2. The rotor according to claim 1, wherein the shatterproof member includes layer ends (60, 61-66, 67) which are axial ends of each of the plurality of layers, the layer ends including a winding start portion (60) of the sheet material, a winding end portion (67) of the sheet material, and the transition portion, and an equal number of the layer ends are provided at equally spaced positions in the circumferential direction of the winding range.

3. A rotor according to claim 1, wherein in each of said plurality of layers, said sheet material is spirally wound so as to provide a gap (S) between adjacent ones of said sheet material in the axial direction.

4. The rotor according to claim 3, wherein the shatterproof member includes layer ends (60, 61-66, 67) which are the axial ends of each of the plurality of layers, and when the innermost layer of the plurality of layers is numbered as number 1, the helical angles of the sheet material relative to the axis are equal in the Nth layer and the (N+2)th layer, and the positions of the layer ends are shifted in the circumferential direction.

5. A method for manufacturing a rotor (10) comprising: an annular magnet portion (22) in which a plurality of permanent magnets (31) are arranged in an annular shape along the circumferential direction; and a shatterproof member (23) covering the entire outer circumferential surface (22a) of the annular magnet portion, wherein the shatterproof member is formed by spirally winding a sheet material (51) made of a fiber-reinforced resin material obtained by solidifying a fiber bundle (52) with a resin base material (53) in a winding range (Aw) including at least the entire outer circumferential surface of the annular magnet portion, and the shatterproof member includes a plurality of layers (X1 to X7) formed continuously from one of the sheet material and overlapping in the radial direction, and transition portions (61 to 66) between adjacent layers in the plurality of layers, which are portions of the sheet material, and each of the plurality of layers is formed by spirally winding the sheet material in the winding range around the axis (L1) of the rotor, The transition portion has a straight portion (70) located at an axial end (E1, E2) of the winding range and extending along a plane perpendicular to the axis.

Images