JP2015089169A - Method for manufacturing rotor and device for manufacturing rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a rotor and a device for manufacturing a rotor, which allow a permanent magnet to be firmly fixed to a rotor core.SOLUTION: A coating magnet 21 is used in which a film layer 15 made of a resin material is formed on a permanent magnet 4 having such a shape that the permanent magnet 4 can be inserted to an insertion hole 13 formed in a rotor core 3 without contact with an inner peripheral surface of the insertion hole 13, and the coating magnet 21 is inserted to the insertion hole 13 of the rotor core 3 heated at a fusion temperature or higher at which the resin material is fused. Further, a cooling liquid is supplied to a flow channel of a pallet 32 from a cooling unit to cool the rotor core 3 after the coating magnet 21 is inserted to the insertion hole 13. In addition, the rotor core 3 for use is constituted by laminating a plurality of electromagnetic steel sheets 11, and the coating magnet 21 for use has a chamfered part 22 formed on an end surface in an insertion direction.

Description

  The present invention relates to a rotor manufacturing method and a rotor manufacturing apparatus.

  2. Description of the Related Art Conventionally, a rotor of a rotating electrical machine is widely known as a so-called embedded magnet type in which a permanent magnet is inserted into an insertion hole formed in a rotor core and fixed in such a manner that the permanent magnet is embedded in the rotor core.

  As a method for manufacturing such a rotor, in recent years, a coated magnet in which a film layer made of a resin material is provided on a permanent magnet that is slightly smaller than the insertion hole of the rotor core is used. There has been proposed a method of fixing a permanent magnet to a rotor core by inserting it into the insertion hole (for example, Patent Document 1). This method has an advantage that, for example, the surface of the permanent magnet is hardly damaged as compared with the case where the permanent magnet is lightly press-fitted into the insertion hole and fixed.

JP 2006-174537 A

  By the way, in the method of Patent Document 1, since the coating layer is scraped when the coating magnet is inserted into the insertion hole, the dimension of the sectional shape of the coating magnet is substantially equal to the dimension of the sectional shape of the insertion hole. As a result, the coated magnet (film layer) does not come into strong contact with the inner peripheral surface of the insertion hole, and the permanent magnet may be insufficiently fixed to the rotor core.

  The present invention has been made to solve the above problems, and an object thereof is to provide a rotor manufacturing method and a rotor manufacturing apparatus capable of firmly fixing a permanent magnet to a rotor core.

  A method of manufacturing a rotor that solves the above-described problem is a mode in which the permanent magnet is embedded in the rotor core by inserting a coated magnet in which a coating layer made of a resin material is provided on the permanent magnet into an insertion hole formed in the rotor core. The permanent magnet has a shape that can be inserted into the insertion hole without contacting the inner peripheral surface of the insertion hole, and can be press-fitted into the insertion hole as the coating magnet. The gist is to insert the coating magnet into the insertion hole in a state where the rotor core is heated to a melting temperature or higher at which the resin material melts.

  According to the above configuration, since the rotor core is heated to a temperature equal to or higher than the melting temperature of the resin material, the coating layer is melted when the coating magnet is inserted into the insertion hole, and the melted resin is minute on the inner peripheral surface of the insertion hole. Adheres to unevenness. Thereby, since a membrane | film | coat layer adheres to both the surface of a permanent magnet and the internal peripheral surface of an insertion hole, a permanent magnet can be firmly fixed with respect to a rotor core.

In the rotor manufacturing method, it is preferable that the rotor core is cooled using a cooling device after the coating magnet is inserted into the insertion hole.
According to the above configuration, since the resin (film layer) melted when the coated magnet is inserted is quickly solidified, the position of the permanent magnet in the insertion hole can be quickly stabilized.

In the above-described rotor manufacturing method, it is preferable to use the rotor core configured by laminating a plurality of steel plates.
According to the above configuration, since the resin (film layer) melted when the coating magnet is inserted into the insertion hole enters the gap between the steel plates, the permanent magnet can be firmly fixed to the rotor core.

In the rotor manufacturing method, it is preferable to use a coating magnet having a chamfered portion formed on an end surface in the insertion direction of the coating magnet.
According to the above configuration, since the chamfered portion is formed on the end surface in the insertion direction, the coating magnet can be smoothly inserted into the insertion hole.

  An apparatus for manufacturing a rotor that solves the above-described problem is an aspect in which the permanent magnet is embedded in the rotor core by inserting a coating magnet having a permanent magnet provided with a coating layer made of a resin material into an insertion hole formed in the rotor core. The invention is characterized in that when the coating magnet is inserted into the insertion hole, a heating device is provided that heats the rotor core to a melting temperature or higher at which the resin material melts. According to the above configuration, the permanent magnet can be firmly fixed to the rotor core.

  The rotor manufacturing apparatus preferably includes a cooling device that cools the rotor core after the coating magnet is inserted into the insertion hole. According to the above configuration, the position of the permanent magnet in the insertion hole can be quickly stabilized.

  According to the present invention, the permanent magnet can be firmly fixed to the rotor core.

(A) is a top view of a rotor, (b) is sectional drawing along the axial direction of a rotor (AA sectional drawing of Fig.1 (a)). (A) is a front view of a coated magnet, (b) is a side view of the coated magnet, and (c) is a plan view of the coated magnet. The schematic block diagram of the manufacturing apparatus of a rotor. (A)-(c) is a schematic diagram which shows the manufacturing process of a rotor.

Hereinafter, an embodiment of a rotor manufacturing method and a rotor manufacturing apparatus will be described with reference to the drawings.
First, the configuration of the rotor will be described.
As shown in FIGS. 1A and 1B, the rotor 1 includes a rotor core 3 fixed so as to be integrally rotatable with the rotary shaft 2, and a plurality of (in the present embodiment, fixed in an embedded manner in the rotor core 3). 4) permanent magnets 4 are provided.

  Specifically, the rotor core 3 is configured by laminating a plurality of electromagnetic steel plates 11 and is formed in a columnar shape. A fitting hole 12 penetrating in the axial direction is formed in the center of the rotor core 3, and the fitting hole 12 is press-fitted into the outer periphery of the rotating shaft 2 so as to be rotatable together with the rotating shaft 2. ing. That is, the rotor 1 of this embodiment is configured as an inner rotor. A plurality (four in this embodiment) of insertion holes 13 penetrating in the axial direction are formed in the outer peripheral edge of the rotor core 3. The cross-sectional shape orthogonal to the axial direction of each insertion hole 13 is a rectangular shape, and the longitudinal direction of the rectangle formed by the cross-section is formed so as to be substantially orthogonal to the radial line passing through the center.

  The permanent magnet 4 employs a segment magnet made of a sintered magnet or the like, and is formed in a rectangular plate shape. The cross-sectional shape perpendicular to the axial direction of the rotor 1 in the permanent magnet 4 is a rectangular shape that is slightly smaller than the cross-sectional shape of the insertion hole 13 and can be inserted without contacting the inner peripheral surface of the insertion hole 13. It has become. Specifically, the longitudinal length L1 of the rectangle formed by the cross section of the permanent magnet 4 is set shorter than the longitudinal length L2 of the rectangle formed by the cross section of the insertion hole 13. Further, the rectangular length L3 formed by the cross section of the permanent magnet 4 is set shorter than the rectangular length L4 formed by the cross section of the insertion hole 13. The length of the permanent magnet 4 along the axial direction of the rotor 1 is set shorter than the length of the insertion hole 13 along the axial direction. Further, the permanent magnet 4 is magnetized in the plate thickness direction (direction substantially along the radial direction of the rotor 1) so that the polarities appearing on the outer peripheral side of the rotor core 3 are alternately opposite along the circumferential direction. .

  The permanent magnet 4 is provided with a coating layer 15 made of a resin material. As the resin material, an epoxy resin having thermosetting and insulating properties is employed. The permanent magnet 4 is fixed to the rotor core 3 by the film layer 15 being in close contact with both the surface of the permanent magnet 4 and the inner peripheral surface of the insertion hole 13. The permanent magnet 4 of this embodiment is subjected to a surface treatment (for example, nickel plating) for the purpose of preventing rust.

Next, the manufacture of the rotor will be described.
When manufacturing the rotor 1, the electromagnetic steel plates 11 are laminated to manufacture the rotor core 3, and then the permanent magnet 4 is fixed to the rotor core 3. Here, in this embodiment, insertion of the rotor core 3 in which the coating magnet 21 provided with the coating layer 15 on the permanent magnet 4 shown in FIG. 2 is heated to a melting temperature or higher at which the resin material melts by the manufacturing apparatus 31 shown in FIG. The permanent magnet 4 is fixed to the rotor core 3 by being inserted into the hole 13.

  Specifically, as shown in FIGS. 2A to 2C, the coating magnet 21 is configured by providing a thin film layer 15 that covers the entire surface of the permanent magnet 4, and is formed in a rectangular plate shape. ing. The cross-sectional shape orthogonal to the direction in which the coating magnet 21 is inserted into the rotor core 3 (the axial direction of the rotor 1) is a rectangular shape that is slightly larger than the cross-sectional shape of the insertion hole 13, and is press-fitted into the insertion hole 13 (light press-fitting). ) Is possible. Specifically, the longitudinal length L5 of the rectangle formed by the cross section of the coating magnet 21 (the permanent magnet 4 and the coating layer 15) is set longer than the longitudinal length L2 of the insertion hole 13. In addition, the rectangular length L6 formed by the cross section of the coating magnet 21 is set to be longer than the length L4 of the insertion hole 13 in the short direction. The length of the coating magnet 21 along the axial direction of the rotor 1 is set to be approximately equal to the length of the insertion hole 13 along the axial direction.

  Further, chamfered portions 22 are formed by chamfering the coating layer 15 over the entire circumference on both end faces of the coating magnet 21 in the insertion direction. Note that the chamfered portion 22 of the present embodiment is formed in a sloped shape inclined by approximately 45 ° with respect to the insertion direction. Moreover, the coating magnet 21 of this embodiment is manufactured by immersing the permanent magnet 4 in a storage tank (not shown) in which a molten resin material is stored and then pulling it up.

  As shown in FIG. 3, the manufacturing apparatus 31 supplies the coating magnet 21 to the plurality of pallets 32 that convey the rotor core 3 in the previous stage to which the permanent magnet 4 is fixed, and the rotor core 3 on the pallet 32 that is sequentially conveyed. A supply unit 33, a cooling unit 34 for supplying a cooling liquid to the pallet 32, and a control device 35 for controlling these operations are provided.

  Specifically, the pallet 32 is made of a metal material having excellent thermal conductivity and is formed in a square plate shape. The pallet 32 incorporates a heating device (heater) 41 made of a heating wire or the like. The rotor core 3 placed on the pallet 32 is heated to a predetermined heating temperature (for example, about 200 ° C.) equal to or higher than the melting temperature at which the resin material melts by the operation of the heating device 41.

  The pallet 32 is formed with a flow path 42 extending in a plane parallel to the placement surface on which the rotor core 3 is placed. A connection portion 44 for connecting the tube 43 of the cooling unit 34 to the flow path 42 is provided at an opening portion of the flow path 42 in the pallet 32. In addition, the connection part 44 of this embodiment is comprised so that the tube 43 can be attached or detached automatically with the movement of the pallet 32. FIG. The rotor core 3 placed on the pallet 32 is supplied with a cooling liquid from the cooling unit 34 to the flow path 42, whereby a predetermined cooling temperature (e.g., 170) below the curing temperature at which the thermosetting resin material is cured. It is cooled to about ° C. That is, in this embodiment, the cooling device is configured by the flow path 42 and the cooling unit 34 of the pallet 32.

  The supply unit 33 includes an arm (not shown) that can hold the coating magnet 21. The supply unit 33 takes out the coating magnet 21 from a storage unit (not shown) that stores a large number of coating magnets 21, and is transported to a predetermined position. The coating magnet 21 is supplied to the rotor core 3 on the pallet 32.

Next, a procedure (action) for fixing the permanent magnet to the rotor core will be described.
As shown in FIG. 4A, when the rotor core 3 is placed on the pallet 32, the control device 35 operates the heating device 41 to heat the rotor core 3 (pallet 32) to a predetermined heating temperature. Transport to a predetermined position before 33. Subsequently, as shown in FIG. 4B, when the rotor core 3 is heated to a predetermined heating temperature, the operation of the supply unit 33 is controlled to insert the coating magnet 21 into the insertion hole 13 (light press-fitting).

  Here, the inner peripheral surface of the insertion hole 13 is macroscopically flat, but is adjacent to the microscopically uneven shape as shown in an enlarged view in FIG. There is a gap between the electromagnetic steel sheets 11. Therefore, when the coating magnet 21 is inserted into the insertion hole 13, the resin melted in the coating layer 15 in contact with the inner peripheral surface thereof adheres to minute irregularities on the inner peripheral surface of the insertion hole 13 and the electromagnetic steel sheet 11. Get into the gap between. At this time, since the rotor core 3 is heated, the melted resin is hard to solidify, and the resin is likely to enter the back of the gap. Then, when the insertion of the coating magnet 21 into each insertion hole 13 is completed, the control device 35 connects the tube 43 to the connecting portion 44 and flows the coolant from the cooling unit 34 as shown in FIG. The rotor core 3 is cooled by supplying to the path 42, and the permanent magnet 4 is fixed to the rotor core 3.

Next, the effect of this embodiment will be described.
(1) The permanent magnet 4 is fixed to the rotor core 3 by inserting the coating magnet 21 into the insertion hole 13 of the rotor core 3 heated to a predetermined heating temperature equal to or higher than the melting temperature of the resin material. Thereby, since the coating layer 15 is in close contact with both the surface of the permanent magnet 4 and the inner peripheral surface of the insertion hole 13, the permanent magnet 4 can be firmly fixed to the rotor core 3.

  (2) Since the rotor core 3 is cooled by supplying the coolant to the flow path 42 of the pallet 32 after the coating magnet 21 is inserted into the insertion hole 13, the resin melted when the coating magnet 21 is inserted ( The coating layer 15) hardens quickly. Thereby, the position of the permanent magnet 4 in the insertion hole 13 can be quickly stabilized.

  (3) Since the rotor core 3 is configured by laminating a plurality of electromagnetic steel plates 11, the resin (film layer 15) melted when the coating magnet 21 is inserted into the insertion hole 13 enters the gap between the electromagnetic steel plates 11. Thereby, the permanent magnet 4 can be firmly fixed to the rotor core 3.

(4) Since the chamfered portion 22 is formed on the end surface of the coated magnet 21 in the insertion direction, the coated magnet 21 can be smoothly inserted into the insertion hole 13.
In addition, the said embodiment can also be implemented in the following aspects which changed this suitably.

  -In the said embodiment, although the rectangular-plate-shaped segment magnet corresponding to the shape of the insertion hole 13 was used as the permanent magnet 4, it is not restricted to this, For example, a several division | segmentation magnet interposes an insulator between these. You may use what was laminated | stacked on the axial direction. By comprising in this way, the eddy current which generate | occur | produces in the permanent magnet 4 at the time of rotation of the rotor 1 can be reduced, and it can suppress that this permanent magnet 4 overheats.

  In the above embodiment, the coated magnet 21 is manufactured by immersing the permanent magnet 4 in a storage tank in which the molten resin is stored and then pulling it up. However, the present invention is not limited to this. For example, the coated magnet 21 is manufactured by injection molding or the like. May be.

  In the above embodiment, the coating layer 15 is provided so as to cover the entire surface of the permanent magnet 4. However, the present invention is not limited to this. For example, the coating layer 15 is exposed so that a part of the end surface of the permanent magnet 4 in the insertion direction is exposed. May be provided.

  In the above embodiment, the chamfered portion 22 is formed in a slope shape. Further, the chamfered portion 22 may not be formed on the coating magnet 21.

-In the said embodiment, although what has thermosetting and insulation was used as a resin material, you may use not only this but what has thermoplasticity and electroconductivity.
In the above embodiment, the permanent magnet 4 is formed in a rectangular plate shape. However, the present invention is not limited to this, and the permanent magnet 4 may be formed in an arc shape as long as it can be inserted without contacting the inner peripheral surface of the insertion hole 13. A curved plate shape may be used, and the shape can be changed as appropriate.

-In above-mentioned embodiment, although the surface treatment was performed to the permanent magnet 4, it is not restricted to this but does not need to perform a surface treatment.
In the above embodiment, the insertion holes 13 are formed to open on both sides in the axial direction of the rotor 1. However, the present invention is not limited to this, and the insertion holes 13 may be formed only on one end in the axial direction and closed on the other end in the axial direction. Needless to say, the cross-sectional shape of the insertion hole 13 may not be rectangular, and may be, for example, an arc.

  In the above embodiment, the rotor core 3 is formed in a cylindrical shape and the outer diameter shape is circular. However, in order to improve motor characteristics (for example, cogging torque, torque ripple, or maximum torque), the outer diameter shape is changed. It is good also as shapes other than circular shape (perfect circle shape).

  In the above embodiment, the rotor core 3 is configured by laminating a plurality of electromagnetic steel plates 11. However, the present invention is not limited thereto, and the rotor core 3 may be configured by a columnar integrally formed product made of a soft magnetic material such as iron.

  In the above embodiment, the rotor core 3 is cooled by supplying the coolant to the flow path 42 formed in the pallet 32. However, the present invention is not limited to this, and the rotor core 3 is cooled by blowing air with a fan or the like. May be. In addition, the rotor core 3 may be naturally cooled without providing the cooling device in the manufacturing apparatus 31.

  In the above-described embodiment, the manufacturing apparatus 31 includes a plurality of pallets 32 in which the heating apparatus 41 is built. However, the present invention is not limited to this. For example, the manufacturing apparatus 31 includes only one pallet 32 in which the heating apparatus 41 is built. Before inserting 21, the rotor core 3 may be transferred from another pallet without a heating device.

  In the above embodiment, the rotor 1 configured as an inner rotor is manufactured, but a rotor configured as an outer rotor may be manufactured.

  DESCRIPTION OF SYMBOLS 1 ... Rotor, 3 ... Rotor core, 4 ... Permanent magnet, 11 ... Electromagnetic steel plate (steel plate), 13 ... Insertion hole, 15 ... Film layer, 21 ... Coated magnet, 22 ... Chamfer part, 31 ... Manufacturing apparatus, 32 ... Pallet, 33 ... Supply unit, 34 ... Cooling unit (cooling device), 41 ... Heating device, 42 ... Flow path (cooling device).

Claims (6)

In the method of manufacturing a rotor, in which the permanent magnet is fixed in an embedded manner in the rotor core by inserting a coating magnet provided with a coating layer made of a resin material on the permanent magnet into an insertion hole formed in the rotor core.
As the permanent magnet, a shape that can be inserted into the insertion hole without contacting the inner peripheral surface of the insertion hole, and a coating magnet that has a shape that can be press-fitted into the insertion hole,
A method for manufacturing a rotor, wherein the coating magnet is inserted into the insertion hole in a state where the rotor core is heated to a melting temperature or higher at which the resin material melts. In the manufacturing method of the rotor according to claim 1,
A rotor manufacturing method comprising: cooling the rotor core using a cooling device after inserting the coating magnet into the insertion hole. In the manufacturing method of the rotor according to claim 1 or 2,
A method for manufacturing a rotor, wherein the rotor core is formed by laminating a plurality of steel plates. In the manufacturing method of the rotor according to any one of claims 1 to 3,
A method for manufacturing a rotor, wherein the coated magnet has a chamfered portion formed on an end surface in the insertion direction of the coated magnet. In the rotor manufacturing apparatus in which the permanent magnet is fixed in an embedded manner in the rotor core by inserting a coating magnet provided with a film layer made of a resin material on the permanent magnet into an insertion hole formed in the rotor core.
An apparatus for manufacturing a rotor, comprising: a heating device that heats the rotor core to a melting temperature or higher at which the resin material melts when the coating magnet is inserted into the insertion hole. The rotor manufacturing apparatus according to claim 5,
An apparatus for manufacturing a rotor, comprising: a cooling device that cools the rotor core after the coating magnet is inserted into the insertion hole.