Rotor and method of manufacturing the rotor

Abstract

To provide a rotor and a rotor manufacturing method which can reduce anxiety of fiber disconnection in a CFRP material for scatter prevention of a permanent magnet.SOLUTION: A scatter prevention member 23 of a permanent magnet 22 in a rotor 12 is composed of a fiber rich layer in an inner diameter side part and a resin rich layer in an outer diameter side part using a CFRP material. A scatter prevention member 23 in which fibers and resins are deviated is manufactured by applying high tension to a ribbon-like base material 23x of the CFRP material, and winding and heat curing it.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to rotors having permanent magnets and methods of manufacturing rotors. [Background technology]

[0002] Some motor rotors are known to have multiple permanent magnets arranged on the outer surface of the rotor base as magnetic poles. When the rotor rotates, the permanent magnets are subjected to centrifugal force toward the outer diameter, which can cause them to float toward the outer diameter and fly away. For this reason, some permanent magnets are provided with a scattering prevention member that covers part or all of the outer surface of the permanent magnets.

[0003] One example of a shatterproof member is a carbon fiber reinforced plastic (CFRP) material (see, for example, Patent Document 1). The use of CFRP material for rotor components is particularly suitable when the rotor is required to be lightweight and capable of high rotation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-91202 Summary of the Invention [Problem to be solved by the invention]

[0005] CFRP materials are composite materials that contain a resin matrix, such as thermosetting resin, and carbon fibers. When using materials with a higher volumetric content of carbon fibers, the protective effect of the resin on the reinforcing fibers can be reduced. This increases the risk of the reinforcing fibers breaking due to external stimuli, so ingenuity is required when using them.

[0006] An object of the present disclosure is to provide a rotor and a method for manufacturing the rotor that can reduce the risk of fiber breakage in CFRP materials used to prevent permanent magnets from scattering. [Means for solving the problem]

[0007] The rotor that solves the above problem is a rotor (12) comprising a rotor base (21), a plurality of permanent magnets (22) arranged circumferentially on the outer surface (21a) of the rotor base, and a scattering prevention member (23) attached in a manner that surrounds the rotor along the outer surfaces (22b) of the plurality of permanent magnets, wherein the scattering prevention member is made of a carbon fiber reinforced plastic material (referred to as CFRP material) that includes a resin base material (23a) and carbon fibers (23b), and the inner diameter side portion (A1) on the inner diameter side of the rotor forms a fiber-rich layer, and the outer diameter side portion (A2) forms a resin-rich layer.

[0008] According to the above configuration, the shatter prevention member for the permanent magnets in the rotor is made of CFRP material, with the inner diameter side being a fiber-rich layer and the outer diameter side being a resin-rich layer. Therefore, even if an external force acts on the shatter prevention member, the outer diameter side portion of the resin-rich layer can effectively absorb the external force. In other words, the action of external force on the carbon fibers of the CFRP material is suppressed, making it possible to reduce events that lead to breakage of the carbon fibers.

[0009] A method for manufacturing a rotor that solves the above-mentioned problems is a method for manufacturing a rotor (12) comprising a rotor base (21), a plurality of permanent magnets (22) arranged circumferentially on an outer surface (21a) of the rotor base, and a shatter prevention member (23) attached in a manner that surrounds the rotor along the outer surfaces (22b) of the plurality of permanent magnets, wherein the shatter prevention member uses a ribbon-shaped material (23x) of CFRP material including a resin base material (23a) and carbon fibers (23b), and is wound around the rotor in a state in which a high tension is applied so that the movement of the carbon fibers in the ribbon-shaped material toward the inner diameter side of the rotor is promoted during the process of melting the resin base material during a heat-curing treatment, and the high tension state of the ribbon-shaped material is maintained during the heat-curing treatment, so that an inner diameter side portion (A1) on the inner diameter side of the rotor forms a fiber-rich layer and an outer diameter side portion (A2) forms a resin-rich layer.

[0010] According to the above method, the shatterproof member for the permanent magnet in the rotor is manufactured using CFRP material, with the inner diameter side portion being a fiber-rich layer and the outer diameter side portion being a resin-rich layer. As with the above, it is possible to reduce events that lead to carbon fiber breakage. Furthermore, by applying high tension to a ribbon-shaped CFRP material and undergoing winding and heat-curing treatment, it is possible to easily manufacture a shatterproof member with the inner diameter side portion being a fiber-rich layer and the outer diameter side portion being a resin-rich layer. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating the configuration of a motor having a rotor according to an embodiment. [Figure 2] FIG. 2 is a perspective view of a rotor according to the embodiment. [Figure 3] 5A to 5C are explanatory diagrams showing a manufacturing process of the rotor in the same embodiment. [Figure 4] 1A and 1B are explanatory views showing the rotor manufacturing process, in which FIG. 1A is a view before heat hardening treatment, and FIG. 1B is a view after heat hardening treatment. [Figure 5] 1A and 1B are explanatory views showing the rotor manufacturing process, in which FIG. 1A is a view before heat hardening treatment, and FIG. 1B is a view after heat hardening treatment. DETAILED DESCRIPTION OF THE INVENTION

[0012] An embodiment of a rotor and a method for manufacturing the rotor will now be described. (Configuration of motor 10) As shown in FIG. 1, a motor 10 of this embodiment includes a stator 11 and a rotor 12. The stator 11 is configured in a substantially circular ring shape. The stator 11 has, for example, 24 coil magnetic pole portions (not shown) arranged in the circumferential direction. A rotor 12 is rotatably disposed inside the stator 11. The stator 11 generates a rotating magnetic field for driving the rotor 12 to rotate based on the energization of its own coil magnetic pole portions. The motor 10 of this embodiment is intended for use as a high-speed motor with a maximum operating speed of 12,000 rpm or more, for example.

[0013] (Configuration of rotor 12) As shown in FIGS. 1 and 2, the rotor 12 of this embodiment includes a rotor base 21, a permanent magnet 22, and a scattering prevention member 23.

[0014] The rotor base 21 is configured to be approximately cylindrical overall. The rotor base 21 has a hollow structure in consideration of weight reduction and other factors. One axial end portion of the rotor base 21 is integrally configured as an output shaft portion 21x. On the outer surface 21a on the other axial end side of the rotor base 21, for example, 20 permanent magnets 22 are arranged in the circumferential direction. In other words, the rotor 12 has 20 magnetic pole portions in the circumferential direction.

[0015] The permanent magnets 22 are generally rectangular. An inner surface 22a of the permanent magnets 22, which forms the inner diameter side of the rotor 12, abuts against an outer surface 21a of the rotor base 21. The inner surface 22a and the outer surface 21a form circumferential or flat surfaces. An outer surface 22b of the permanent magnets 22, which forms the outer diameter side of the rotor 12, forms a uniform outer peripheral surface of the rotor 12 with all the permanent magnets 22 in the circumferential direction. Side end surfaces 22c on both sides of the permanent magnets 22 in the circumferential direction of the rotor 12 abut against the side end surfaces 22c of adjacent permanent magnets 22.

[0016] As an example, the permanent magnet 22 is configured as a Halbach array magnet. Specifically, the permanent magnet 22 is divided into three regions in the circumferential direction with different magnetization patterns. Both circumferential side portions of the permanent magnet 22 are magnetized in a manner that generates magnetic flux oriented in the radial direction. The circumferential center portion of the permanent magnet 22 is magnetized in a manner that generates magnetic flux oriented in a direction perpendicular to the radial direction, i.e., in the circumferential direction, and magnetic flux oriented in the circumferential direction.

[0017] The shatterproof member 23 is attached to the rotor 12 along the outer surfaces 22b of the multiple permanent magnets 22 in the circumferential direction. The shatterproof member 23 is cylindrical and completely covers the permanent magnets 22. The shatterproof member 23 of this embodiment is made of a carbon fiber reinforced plastic material (referred to as a CFRP material).

[0018] (Configuration and installation method of shatterproof member 23) As shown in FIG. 3, the shatterproof member 23 made of CFRP material is a composite material including a resin base material 23a such as a thermosetting resin and carbon fibers 23b. In this embodiment, the volume content of the carbon fibers 23b is 60 to 70%. In this embodiment, the shatterproof member 23 is made of a ribbon-shaped material 23x. The ribbon-shaped material 23x has a width smaller than the axial length of the permanent magnet 22. The ribbon-shaped material 23x is wound around the permanent magnet 22 of the rotor 12 several times so that the permanent magnet 22 is not exposed. In this case, the ribbon-shaped material 23x is wound in one or more layers.

[0019] After the ribbon-shaped material 23x is wound as required, it is heated to melt and harden the resin base material 23a. While the heating temperature for CFRP materials is typically 160 to 180°C, in this embodiment, it is set to a temperature range of 130 to 140°C, which minimizes the demagnetization effect of the permanent magnets 22. In this manner, a cylindrical shatterproof member 23, in which the resin base material 23a is integrally fused and hardened, is produced on the outer diameter side of the permanent magnets 22. By producing the shatterproof member 23, the permanent magnets 22 are firmly fixed to the rotor base 21 in close contact with the outer surface 21a of the rotor base 21, and the side end surfaces 22c of adjacent permanent magnets 22 are also in close contact with each other. In this case, the permanent magnets 22 may be fixed using an adhesive, or the adhesive may be omitted. For example, if the outer diameter of the permanent magnet 22 portion of the rotor 12 is 90 mm, the thickness of the shatterproof member 23 is set to approximately 0.4 mm.

[0020] Furthermore, in this embodiment, a tension greater than the general tension is used when winding the ribbon-shaped material 23x. Specifically, when winding the ribbon-shaped material 23x, a tension of, for example, about 100 [N] is generally used, which prevents wrinkles and prevents shifting during heating and after curing. In contrast, in this embodiment, a tension of, for example, 250 to 500 [N] is used when winding the ribbon-shaped material 23x. Furthermore, in this embodiment, the state in which the ribbon-shaped material 23x is subjected to high tension is maintained by a jig (not shown) or the like, during heat curing.

[0021] (Action of this embodiment) The operation of this embodiment will be described. FIG. 4(a) shows a state in which one layer of ribbon-shaped material 23x is wound during the process of fabricating shatterproof member 23 for permanent magnet 22. A high tension state is maintained on the wound ribbon-shaped material 23x using a jig or the like. When the ribbon-shaped material 23x is subjected to a heat curing process, the carbon fibers 23b of the ribbon-shaped material 23x are subjected to high tension during the melting process of the resin base material 23a, as shown in FIG. 4(b), which promotes their movement toward the permanent magnet 22, which is the inner diameter side of the rotor 12. Therefore, after the resin base material 23a is cured, that is, in shatterproof member 23, the inner diameter side portion A1, which is the inner diameter side of the rotor 12, becomes a fiber-rich layer, and the outer diameter side portion A2 becomes a resin-rich layer. Therefore, even if an external stimulus acts on shatterproof member 23, the outer diameter side portion A2 of the resin-rich layer effectively absorbs the external force, suppressing the external force from acting on the carbon fibers 23b. This reduces the risk of the carbon fibers 23b breaking.

[0022] Furthermore, by manufacturing the anti-scattering member 23 with high tension applied to the ribbon-shaped material 23x, it is possible to generate a clamping force F2 on the inner diameter side of the rotor 12 that is greater than the centrifugal force F1 of the permanent magnet 22 generated when the rotor 12 is rotating at its maximum operating speed.

[0023] 5(a) and 5(b) show a state in which the ribbon-shaped material 23x is wound in multiple layers, such as two layers. Even when the ribbon-shaped material 23x is wound in multiple layers, the high tension state is maintained during the heat treatment, so that the carbon fibers 23b tend to move from the wound layer toward the inner diameter side of the rotor 12. Therefore, the shatterproof member 23 is similarly fabricated such that the inner diameter side region A1, which is the inner diameter side of the rotor 12, is a fiber-rich layer, and the outer diameter side region A2 is a resin-rich layer.

[0024] (Effects of this embodiment) The effects of this embodiment will be described. (1) The shatter prevention member 23 for the permanent magnet 22 in the rotor 12 is made of CFRP material, with the inner diameter side portion A1 being a fiber-rich layer and the outer diameter side portion A2 being a resin-rich layer. Therefore, even if an external stimulus acts on the shatter prevention member 23, the outer diameter side portion A2 of the resin-rich layer can suitably absorb the external force. In other words, the action of the external force on the carbon fibers 23b of the CFRP material can be suppressed, and events that lead to breakage of the carbon fibers 23b can be reduced.

[0025] (2) The fiber-rich layer in the inner diameter portion A1 of the shatterproof member 23 minimizes the effects of deformation and deterioration of the resin due to use and aging. Therefore, the reduction in the fastening force F2 of the shatterproof member 23 is minimal, and the function of the shatterproof member 23 can be maintained for a long time.

[0026] (3) By using the ribbon-shaped material 23x made of CFRP, it is possible to easily manufacture the shatterproof member 23. In addition, by applying high tension to the ribbon-shaped material 23x made of CFRP, and then winding and heat-curing the material, it is possible to easily manufacture the shatterproof member 23 of this embodiment, in which the fibers and resin are biased.

[0027] (4) The scattering prevention member 23 exerts a clamping force F2 on the inner diameter side of the rotor 12 that is greater than the centrifugal force F1 of the permanent magnets 22 generated at the maximum rotation speed of the rotor 12. This makes it possible to more reliably prevent the permanent magnets 22 from scattering.

[0028] (Example of change) This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0029] The above values ​​are examples and may be changed as needed. Although the anti-scattering member 23 is provided to cover the entire permanent magnet 22, the permanent magnet 22 may be partially exposed.

[0030] The shape of the permanent magnet 22 is an example and may be changed as appropriate. Also, although the permanent magnet 22 is a Halbach array magnet as an example, other magnets such as polar anisotropic magnets and radially aligned magnets may also be used.

[0031] Additionally, the configuration of the rotor 12 may be changed as appropriate. The shape of the rotor base 21 may be changed as appropriate. Although the present invention has been applied to a radial type in which the rotor 12 and the stator 11 face each other in the radial direction, it may also be applied to an axial type in which the rotor and the stator face each other in the axial direction.

[0032] (Addendum) The technical ideas that can be understood from the above-described embodiment and modified examples will be described. (A) a rotor (12) including a rotor base (21), a plurality of permanent magnets (22) arranged in the circumferential direction on an outer surface (21a) of the rotor base, and a scattering prevention member (23) attached to the rotor along the outer surfaces of the plurality of permanent magnets in a manner that surrounds the rotor; a stator (11) that generates a rotating magnetic field for driving the rotor; A motor (10) comprising: The shatterproof member of the rotor is made of a CFRP material including a resin base material (23a) and carbon fibers (23b), and an inner diameter side portion (A1) on the inner diameter side of the rotor forms a fiber-rich layer, and an outer diameter side portion (A2) forms a resin-rich layer. Motor. [Explanation of symbols]

[0033] 12 rotor, 21 rotor base, 21a outer surface, 22 permanent magnet, 22b outer surface, 23 anti-scattering member, 23a resin base material, 23b carbon fiber, A1 inner diameter side portion, A2 outer diameter side portion

Claims

1. A rotor base (21); a plurality of permanent magnets (22) arranged in the circumferential direction on the outer surface (21a) of the rotor base; a scattering prevention member (23) attached to the rotor along the outer surfaces (22b) of the plurality of permanent magnets in a manner surrounding the rotor, The shatterproof member is made of a carbon fiber reinforced resin material (referred to as a CFRP material) that contains a resin base material (23a) that is a thermosetting resin and carbon fibers (23b) and has a volume content of the carbon fibers of 60 to 70% and that is subjected to a heat curing treatment, and the inner diameter side portion (A1) that is on the inner diameter side of the rotor forms a fiber-rich layer, and the outer diameter side portion (A2) forms a resin-rich layer, The CFRP material forms a ribbon-shaped material (23x), and the ribbon-shaped material is wound around the rotor a plurality of times; The carbon fibers move from their own layer to the layer on the inner diameter side thereof during winding, thereby forming the fiber-rich layer and the resin-rich layer. Rotor.

2. The anti-scattering member is configured to have a clamping force (F2) on the inner diameter side of the rotor that is equal to or greater than the centrifugal force (F1) of the permanent magnet generated at the maximum rotation speed of the rotor. The rotor of claim 1 .

3. A rotor base (21); a plurality of permanent magnets (22) arranged in the circumferential direction on the outer surface (21a) of the rotor base; a scattering prevention member (23) attached to the rotor along the outer surfaces (22b) of the plurality of permanent magnets in a manner surrounding the rotor, the method comprising: The shatterproof member uses a ribbon-shaped material (23x) made of CFRP material containing a resin base material (23a) and carbon fibers (23b), with the volume content of the carbon fibers being 60 to 70%; the ribbon-shaped material is wound around the rotor a plurality of times in a state where a high tension is applied so that the carbon fibers in the ribbon-shaped material are promoted to move toward the inner diameter side of the rotor during the process of melting the resin base material during a heat curing treatment; and the high tension state of the ribbon-shaped material is maintained during the heat curing treatment, so that the carbon fibers move from their own layer during the winding to the layer on the inner diameter side thereof, thereby producing an inner diameter side portion (A1) on the inner diameter side of the rotor as a fiber-rich layer and an outer diameter side portion (A2) as a resin-rich layer. A method for manufacturing a rotor.

4. The ribbon-shaped material is wound around the rotor a plurality of times in a state where a high tension of 250 to 500 [N] is applied so that the movement of the carbon fibers in the ribbon-shaped material toward the inner diameter side of the rotor is promoted during the process of melting the resin base material during the heat-setting treatment, and the high tension state of 250 to 500 [N] of the ribbon-shaped material is maintained during the heat-setting treatment, so that the carbon fibers move from their own layer during the winding to the layer on the inner diameter side thereof, thereby producing an inner diameter side portion (A1) on the inner diameter side of the rotor as the fiber-rich layer and an outer diameter side portion (A2) as the resin-rich layer. The method for manufacturing the rotor according to claim 3 .

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