WO2023190855A1

WO2023190855A1 - Rotor and method for manufacturing rotor

Info

Publication number: WO2023190855A1
Application number: PCT/JP2023/013151
Authority: WO
Inventors: 訓明松本; 崇平林
Original assignee: 株式会社デンソー
Priority date: 2022-03-31
Filing date: 2023-03-30
Publication date: 2023-10-05
Also published as: JP2023151124A

Abstract

This rotor (12) has a rotor base part (21), a plurality of permanent magnets (22) arranged in a circumferential direction on an outer surface (21a) of the rotor base part, and a scattering prevention member (23) mounted along the outer surface of the plurality of permanent magnets so as to go around the rotor. The scattering prevention member has a tightening force (F2) toward the radially inside of the rotor greater than the centrifugal force (F1) of the permanent magnets generated at the time of maximum rotation during operation of the rotor.

Description

Rotor and rotor manufacturing method

Cross-reference of related applications

This application is based on Japanese Application No. 2022-060568 filed on March 31, 2022, and the contents thereof are incorporated herein.

The present disclosure relates to a rotor having permanent magnets and a method for manufacturing the rotor.

A rotor of a motor is known in which a plurality of permanent magnets are arranged on the outer surface of a rotor base as a magnetic pole part. When the rotor rotates, the permanent magnet receives centrifugal force toward the outer diameter, which causes it to float toward the outer diameter and scatter. 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 magnet.

As an example of a member for preventing scattering, a ribbon-like material is used and is attached in a manner that it goes around the rotor (see, for example, Patent Document 1). For example, the ribbon-shaped material is made of glass fiber reinforced resin. The ribbon-like material is wound with such tension that wrinkles do not occur in the ribbon-like material and no displacement occurs during heating or after curing.

Japanese Patent Application Publication No. 2016-100974

As a member for preventing scattering of permanent magnets, there is a desire to not only have a function of simply preventing scattering of permanent magnets, but also to suppress deformation toward the outer diameter side. Deformation of the scattering prevention member toward the outer diameter side when the rotor rotates leads to setting a large gap between the scattering prevention member and a member disposed on the outer diameter side such as the stator. An increase in this gap leads to an increase in the size of the motor, and in the case of a stator, a decrease in magnetic transmission efficiency.

An object of the present disclosure is to provide a rotor and a method for manufacturing the rotor that can fully exhibit the function of a member for preventing scattering of permanent magnets.
In a first aspect of the present disclosure, the rotor includes a rotor base, a plurality of permanent magnets arranged in a circumferential direction on an outer surface of the rotor base, and a rotor that orbits the rotor along the outer surface of the plurality of permanent magnets. A rotor comprising a scattering prevention member attached in a manner such that the scattering prevention member exerts a tightening force toward the inner diameter side of the rotor that is greater than the centrifugal force of the permanent magnet that occurs when the rotor is used at maximum rotation. have.

According to the above configuration, the permanent magnet scattering prevention member in the rotor has a tightening force toward the inner diameter side of the rotor that is greater than the centrifugal force of the permanent magnet that occurs when the rotor is at its maximum rotation. That is, in the normal use range of the rotor, the clamping force of the scattering prevention member always exceeds the centrifugal force of the permanent magnet. Therefore, in addition to the function of preventing the scattering of the permanent magnet by the scattering prevention member, it is also possible to sufficiently suppress deformation of the scattering prevention member toward the outer diameter side.

In a second aspect of the present disclosure, a method for manufacturing a rotor includes: a rotor base; a plurality of permanent magnets arranged in a circumferential direction on an outer surface of the rotor base; A method for manufacturing a rotor, comprising: a scattering prevention member attached in a manner that the rotor rotates around the rotor, the scattering prevention member including a CFRP material forming a ribbon-like material, and applying high tension to the ribbon-like material. winding the ribbon-like material around the rotor in the attached state; and maintaining a high tension state of the ribbon-like material during heat curing treatment, so that the scattering prevention member is attached to the rotor. It has a tightening force toward the inner diameter side of the rotor that is greater than the centrifugal force of the permanent magnet that occurs at the maximum rotation in use.

According to the above method, the permanent magnet scattering prevention member in the rotor has a tightening force toward the inner diameter side of the rotor that is greater than the centrifugal force of the permanent magnet that occurs when the rotor is at its maximum operating rotation. Similarly to the above, in addition to the function of preventing the scattering of the permanent magnet by the scattering preventing member, it is also possible to sufficiently suppress deformation of the scattering preventing member toward the outer diameter side. In addition, by applying high tension to a ribbon-shaped CFRP material, winding it, and heat-hardening it, it is possible to easily create a scattering prevention member whose clamping force is superior to the centrifugal force of a permanent magnet. It is.

The above objects and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. The drawing is
FIG. 1 is a configuration diagram of a motor having a rotor in one embodiment, FIG. 2 is a perspective view of the rotor in the same embodiment, FIG. 3 is an explanatory diagram showing the manufacturing process of the rotor in the same embodiment, FIG. 4 is a partially enlarged view of the rotor in the same embodiment.

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

(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.

The rotor base 21 has a generally cylindrical shape as a whole. The rotor base 21 has a hollow structure in consideration of weight reduction and the like. One axial end side portion of the rotor base 21 is integrally configured as an output shaft portion 21x. For example, twenty permanent magnets 22 are arranged in the circumferential direction on the outer surface 21a of the rotor base 21 at the other end in the axial direction. That is, the rotor 12 has 20 magnetic pole parts in the circumferential direction.

The permanent magnet 22 has a substantially rectangular shape. The inner surface 22a of the permanent magnet 22 on the inner diameter side of the rotor 12 is in contact with the outer surface 21a of the rotor base 21. The inner surface 22a and the outer surface 21a each form a circumferential surface or a flat surface. The outer surface 22b of the permanent magnet 22, which is on the outer diameter side of the rotor 12, constitutes a uniform outer circumferential surface of the rotor 12 by all the permanent magnets 22 in the circumferential direction. Side end surfaces 22c on both sides of the permanent magnet 22 in the circumferential direction of the rotor 12 are in contact with side end surfaces 22c of adjacent permanent magnets 22.

The permanent magnet 22 is composed of, for example, a Halbach array magnet. Specifically, the permanent magnet 22 is divided into three regions with different magnetization modes in the circumferential direction. Both sides of the permanent magnet 22 in the circumferential direction are magnetized in such a manner that magnetic flux is generated in the radial direction. The circumferential central portion of the permanent magnet 22 is magnetized such that magnetic flux is directed in a direction perpendicular to the radial direction, that is, in the circumferential direction, and magnetic flux is directed toward both sides of the permanent magnet.

The anti-scattering member 23 is attached so as to orbit the rotor 12 along the outer surface 22b of the plurality of permanent magnets 22 in the circumferential direction. The scattering prevention member 23 is provided in a cylindrical shape so as to completely cover the permanent magnet 22. A carbon fiber reinforced resin material (referred to as CFRP material) is used for the scattering prevention member 23 of this embodiment.

(Configuration and mounting method of scattering prevention member 23)
As shown in FIG. 3, the scattering prevention 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, a CFRP material having a volume content of carbon fibers 23b of 60 to 70% is used. Further, the scattering prevention member 23 is made of a ribbon-shaped material 23x in this embodiment. The width of the ribbon-like material 23x is set to be smaller than the axial length of the permanent magnet 22. The ribbon-like material 23x is wound several times around the permanent magnet 22 of the rotor 12 so that the permanent magnet 22 is not exposed. Further, in this case, the ribbon-like material 23x is wound in one layer or in multiple layers.

After the ribbon-like material 23x is wound in a predetermined manner, it is heated to melt and harden the resin base material 23a. The heating temperature for CFRP material is generally 160 to 180 [°C], but in this embodiment, the heating temperature is set to a temperature range of 130 to 140 [°C], where the influence of demagnetization of the permanent magnet 22 is small. There is. In this way, a cylindrical scattering prevention member 23 in which the resin base materials 23a are integrally fused and hardened is produced on the outer diameter side of the permanent magnet 22. By producing the scattering prevention member 23, the permanent magnets 22 are firmly fixed to the rotor base 21 in a state in which the permanent magnets 22 are 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 magnet 22 may also be fixed using an adhesive, or the adhesive may be omitted. Incidentally, while the outer diameter of the permanent magnet 22 portion of the rotor 12 is, for example, 90 [mm], the thickness of the scattering prevention member 23 is set to about 0.4 [mm].

Furthermore, in this embodiment, a tension larger than a general tension is used when winding the ribbon-like material 23x. Generally, when winding the ribbon-like material 23x, a tension of, for example, about 100 [N] is used, which prevents wrinkles and does not cause displacement 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-like material 23x. Further, in the present embodiment, heat curing is performed while maintaining a state in which high tension is applied to the ribbon-shaped material 23x using a jig (not shown) or the like.

(Action of this embodiment)
The operation of this embodiment will be explained.
By producing the scattering prevention member 23 with high tension applied to the ribbon-like material 23x, as shown in FIG. A scattering prevention member 23 having a tightening force F2 toward the inner diameter side is formed. That is, in the normal use range of the rotor 12, the clamping force F2 of the anti-scattering member 23 always exceeds the centrifugal force F1 of the permanent magnet 22. Therefore, in addition to the function of preventing the scattering prevention member 23 from scattering the permanent magnet 22, it is possible to sufficiently suppress the deformation of the scattering prevention member 23 toward the outer diameter side. Further, in the circumferential direction of the rotor 12, the scattering prevention member 23 can also apply a uniform clamping force F2 to the entire outer surface 22b of the permanent magnet 22.

(Effects of this embodiment)
The effects of this embodiment will be explained.
(1) The scattering prevention member 23 of the permanent magnet 22 in the rotor 12 has a tightening force F2 toward the inner diameter side of the rotor 12 that is greater than the centrifugal force F1 of the permanent magnet 22 that occurs when the rotor 12 rotates at its maximum rotation. That is, in the normal use range of the rotor 12, the clamping force F2 of the anti-scattering member 23 always exceeds the centrifugal force F1 of the permanent magnet 22. Therefore, in addition to the function of preventing the scattering prevention member 23 from scattering the permanent magnet 22, deformation of the scattering prevention member 23 toward the outer diameter side can also be sufficiently suppressed. As a result, the gap between the rotor 12 and the stator 11, which is a member disposed on the outer diameter side of the rotor 12 in this embodiment, can be set small. The magnetic transmission efficiency with the stator 11 is improved, and it can also contribute to downsizing of the motor 10.

(2) By using the ribbon-shaped material 23x of CFRP material, the scattering prevention member 23 can be easily manufactured. In addition, by applying high tension to the ribbon-shaped material 23x of CFRP material and passing through the winding and heat hardening treatment, scattering as in this embodiment where the clamping force F2 exceeds the centrifugal force F1 of the permanent magnet 22 can be avoided. The prevention member 23 can be easily produced.

(3) A uniform tightening force F2 of the anti-scattering member 23 acts on the entire outer surface 22b of the permanent magnet 22 in the circumferential direction of the rotor 12. Therefore, the permanent magnet 22 can be kept in a more stable fixed state. Furthermore, when a Halbach array magnet in which three magnet materials are coupled in the circumferential direction is used as the permanent magnet 22, for example, each magnet material can be stably fixed.

(Example of change)
This embodiment can be modified and implemented as follows. This embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

- The various numerical values described above are just examples, and may be changed as appropriate.
- Although the anti-scattering member 23 is provided so as to cover the entire permanent magnet 22, it may be configured so that a portion of the permanent magnet 22 is exposed.

- The shape of the permanent magnet 22 is just an example, and may be changed as appropriate. Further, although the permanent magnet 22 is a Halbach array magnet as an example, other magnets such as a polar anisotropic magnet or a radially oriented magnet may be used.

- In addition, 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.

- Although the present disclosure has been described based on examples, it is understood that the present disclosure is not limited to the examples or structures. The present disclosure also includes various modifications and equivalent modifications. In addition, various combinations and configurations, as well as other combinations and configurations that include only one, more, or fewer elements, are within the scope and scope of the present disclosure.

(Additional note)
The technical ideas that can be understood from the above embodiment and modification examples will be described.
(A) A rotor base (21), a plurality of permanent magnets (22) arranged in the circumferential direction of the outer surface (21a) of the rotor base, and a rotor that orbits along the outer surface of the plurality of permanent magnets. a rotor (12) comprising a scattering prevention member (23) attached in a manner;
a stator (11) that generates a rotating magnetic field for rotationally driving the rotor;
A motor (10) comprising:
The scattering prevention member has a tightening force (F2) toward the inner diameter side of the rotor that is greater than or equal to the centrifugal force (F1) of the permanent magnet that occurs when the rotor is used at its maximum rotation.
motor.

Claims

a rotor base (21);
a plurality of permanent magnets (22) arranged in the circumferential direction of the outer surface (21a) of the rotor base;
a scattering prevention member (23) attached so as to orbit the rotor along the outer surface (22b) of the plurality of permanent magnets;
A rotor (12) comprising:
The scattering prevention member has a tightening force (F2) toward the inner diameter side of the rotor that is greater than or equal to the centrifugal force (F1) of the permanent magnet that occurs when the rotor is used at its maximum rotation.
Rotor.
The scattering prevention member includes a carbon fiber reinforced resin material (referred to as a CFRP material), the CFRP material is a ribbon-shaped material (23x), and the ribbon-shaped material is wound around the rotor.
A rotor according to claim 1.
The scattering prevention member is configured so that the tightening force is applied uniformly to the entire outer surface of the permanent magnet in the circumferential direction of the rotor.
A rotor according to claim 1.
a rotor base (21);
a plurality of permanent magnets (22) arranged in the circumferential direction of the outer surface (21a) of the rotor base;
a scattering prevention member (23) attached so as to orbit the rotor along the outer surface (22b) of the plurality of permanent magnets;
A method of manufacturing a rotor (12) comprising:
The scattering prevention member includes a CFRP material forming a ribbon-like material (23x),
Wrapping the ribbon-shaped material around the rotor while applying high tension to the ribbon-shaped material;
and maintaining a high tension state of the ribbon-like material during heat curing treatment, so that the scattering prevention member is capable of absorbing the centrifugal force (F1) of the permanent magnet of the rotor that is generated at the maximum rotation of the rotor. Has a tightening force (F2) towards the inner diameter side,
Rotor manufacturing method.