JP5274091B2 - Stator manufacturing method for rotating electrical machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a rotary electric machine stator, by which the productivity of the stator can be improved, and a permanent magnet rotary electric machine. <P>SOLUTION: When a stator is manufactured, split cores 2 are annularly arranged to form a stator core 1. Then, with adjacent core-back portions 2a connected to each other, a plurality of outer circumference restraining jigs for restraining the split cores 2 are fitted to the outer circumferential portion of the stator core 1. In this state, a resin mold at a first stage is applied into a slot portion 1a. After that, the outer circumference restraining jigs are removed from the stator core 1, and the temporarily fixed stator core 1 is set within a frame mold 9. Then, a resin mold at a second stage is applied on the outer circumferential portion of the stator core 1. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

The present invention, for example, a permanent magnet rotating electrical machine, in which about the stator manufacturing how the rotary electric machine such as an induction motor and synchronous motor.

  In the conventional stator manufacturing method, the dimension of the stator core is corrected by applying a force uniformly in the inner diameter direction from the outer periphery of the stator core. Further, by applying a resin mold in a state in which the inner diameter dimension is restrained by an inner diameter restraining jig having a shape in which a protrusion and a groove are provided on a cylindrical member, inner diameter roundness is ensured (see, for example, Patent Document 1). .

JP 2001-218429 A

  In the conventional stator manufacturing method as described above, the resin mold is applied in a state where the force is applied from the outer periphery of the stator core and the inner diameter restraining jig is inserted into the slot portion. Even when the force is released, the inner diameter restraining jig is held in the slot portion by hardening of the mold resin. For this reason, it becomes difficult to remove the inner diameter restraining jig after the resin mold is finished, and when the inner diameter restraining jig is removed, the tip of the teeth may be damaged, and the productivity of the stator is remarkably lowered.

The present invention has been made to solve the above problems, an object of the present invention to provide a stator manufacturing how a rotary electric machine capable of improving the stator productivity.

The method of manufacturing a stator for a rotating electrical machine according to the present invention includes a step of attaching winding portions to teeth portions of a plurality of divided cores each having a core back portion and a teeth portion, and arranging the divided cores in an annular shape to form a stator core And a step of attaching an outer periphery restraining jig for restraining the split core to the outer periphery of the stator core in a state where the core back portions adjacent to each other are joined to each other, in a plurality of slot portions formed between the teeth portions the resin mold was facilities, a step of integrating the divided cores, and remove the outer peripheral restraining jigs from the stator core, a resin molded facilities on the outer periphery of the stator core, comprising the step of forming the frame.

  In the stator manufacturing method of the rotating electrical machine according to the present invention, since the resin mold is divided into two stages, the inner peripheral roundness can be improved while eliminating the need for welding for fixing the divided core. Therefore, it is not necessary to use an inner diameter restraining jig having a protrusion on the inner surface, and therefore the productivity of the stator can be improved.

The best mode for carrying out the present invention will be described below with reference to the drawings.
Embodiment 1 FIG.
1 is a sectional view of a stator of an electric motor according to Embodiment 1 of the present invention. In the figure, an annular stator core 1 is configured by arranging a plurality (9 in this example) of split cores 2 in an annular shape. Each divided core 2 has a core back portion 2a located on the outer peripheral side of the stator core 1 and one tooth portion 2b protruding from the core back portion 2a to the inside in the radial direction of the stator core 1. . The core back portions 2a adjacent to each other are joined without welding, that is, without welding.

  Each tooth portion 2b is provided with a winding portion 4 via an insulating material (insulator) 3. A slot portion 1a is formed between adjacent tooth portions 2b. Each slot portion 1 a is filled with a slot resin portion 5. A frame resin portion 6 is provided on the outer peripheral portion of the stator core 1.

  Next, a method for manufacturing the stator of FIG. 1 will be described. FIG. 2 is a process diagram showing a manufacturing procedure of the stator of FIG. When manufacturing the stator of FIG. 1, first, as shown in FIG. 3, the winding portion 4 is attached to the tooth portion 2 b of each split core 2 via the insulating material 3 (step S <b> 1). The split core 2 is configured by caulking and laminating thin plates extracted with a punching die, molding with a compact iron core, or wire cutting and bonding an electromagnetic steel plate.

  Thereafter, as shown in FIG. 4, the nine cores 2 are arranged in an annular shape to form the stator core 1 (step S2). And the end part work of a winding connection part is implemented as needed.

  Next, as shown in FIG. 5, a plurality of outer peripheral restraining jigs 7 that restrain the split core 2 in a state where the core back portions 2 a adjacent to each other are joined are mounted on the outer peripheral portion of the stator core 1. At this time, a radially inward force is applied to the stator core 1 to bring the core back portions 2a into close contact with each other. In addition, a cylindrical inner intrusion prevention jig 8 that prevents the mold resin from entering the stator core 1 is disposed inside the stator core 1.

  In this state, the first-stage resin mold is applied to the slot 1a (step S3). Thereby, the slot resin part 5 is formed in the slot part 1a, and the division | segmentation core 2 is integrated (temporarily fixed) with high precision. After the first-stage resin molding, as shown in FIG. 6, the outer periphery restraining jig 7 and the inner intrusion prevention jig 8 are removed from the stator core 1.

  In addition, as the inner intrusion prevention jig 8, one having an outer diameter smaller than the inner diameter of the stator core 1 is used. This is because the inner peripheral roundness of the stator core 1 is improved by increasing the adhesion between the core back portions 2a adjacent to each other. With respect to the working accuracy of the joint surface between the core back portions 2a, it is possible to secure up to several microns by manufacturing the split core 2 by, for example, die punching, thereby ensuring sufficient inner circumference roundness. Is possible.

  Thereafter, as shown in FIG. 7, the temporarily fixed stator core 1 is set in the frame mold 9, and the inner intrusion prevention jig 8 is disposed inside the stator core 1. This inner intrusion prevention jig 8 may be shared with the first-stage resin mold or may be separate.

  In this state, a second-stage resin mold is applied to the outer periphery of the stator core 1 (step S4). Thereby, the frame resin part 6 which comprises the flame | frame of an electric motor is formed in the outer peripheral part of the stator core 1. FIG. Thereafter, the inner intrusion prevention jig 8 and the frame mold 9 are removed from the stator core 1 and finished as shown in FIG. 1 by finishing the end surface of the frame resin portion 6 as necessary. Complete stator.

  In such a stator manufacturing method, the resin mold is divided into two stages, so that it is possible to improve the roundness of the inner circumference while eliminating the need for welding for fixing the divided core 2, and the protrusion on the outer circumference. Therefore, the stator productivity can be improved.

  Here, in the conventional manufacturing method, since the split core 2 is integrated by welding the joint portions of the core back portions 2a, thermal contraction accompanying the welding occurs in the core back portion 2a. In particular, in the case of a small motor having a small outer diameter, heat shrinkage at the core back portion 2a affects the inner peripheral portion of the stator, and the roundness of the inner peripheral portion of the stator is deteriorated. Further, when the punching accuracy of the teeth portion 2b is insufficient or when welding is insufficient, a gap is generated between the core back portions 2a.

  Deterioration of the roundness of the inner peripheral part of the stator and the gap between the core back parts 2a as described above cause deterioration of cogging torque in the permanent magnet motor. Moreover, in induction motors, electromagnetic noise is generated.

  On the other hand, according to the stator manufacturing method of the first embodiment, the inner peripheral roundness can be improved while eliminating the need for welding for fixing the split core 2, so that the electromagnetic noise and cogging of the motor can be improved. Torque can be reduced.

  Next, FIG. 8 is a sectional view of a permanent magnet rotating electric machine using the stator of FIG. The permanent magnet rotating electric machine has a stator and a rotor provided in the stator. The rotor includes a columnar rotor core 11 provided inside the stator core 1 and a plurality of permanent magnets 12 provided on the outer peripheral portion of the rotor core 11. In this example, a permanent magnet rotating electrical machine having six magnet poles and nine stator slots is shown. Then, when a current is passed through the winding portion 4, rotational torque is obtained by the interaction between the magnetic flux generated by the winding portion 4 and the magnetic flux generated by the permanent magnet 12.

  In such a permanent magnet rotating electric machine, since the core back portions 2a adjacent to each other are joined together without welding, the cogging torque and the torque ripple can be reduced as described above.

Embodiment 2. FIG.
Next, FIG. 9 is a sectional view of a stator of an electric motor according to Embodiment 2 of the present invention. In this example, a V-shaped concave portion 2 c is provided on the radially outer side of the core back portion 2 a of each divided core 2. Other configurations are the same as those in the first embodiment.

  Next, a method for manufacturing the stator in FIG. 9 will be described. The basic manufacturing procedure is the same as that in the first embodiment (FIG. 2). When manufacturing the stator of FIG. 9, first, as shown in FIG. 10, the winding part 4 is attached to the tooth part 2b of each split core 2 via the insulating material 3 (step S1).

  Thereafter, as shown in FIG. 11, the nine divided cores 2 are arranged in an annular shape to form the stator core 1 (step S2). And the end part work of a winding connection part is implemented as needed.

  Next, as shown in FIG. 12, a plurality of outer peripheral restraining jigs 10 that restrain the split core 2 in a state where the core back portions 2 a adjacent to each other are joined are mounted on the outer peripheral portion of the stator core 1. At this time, a radially inward force is applied to the stator core 1 to bring the core back portions 2a into close contact with each other. Moreover, the convex part 10a provided in the outer periphery restraining jig | tool 10 is fitted to the recessed part 2c. Furthermore, a cylindrical inner intrusion prevention jig 8 that prevents the mold resin from entering the inner side of the stator core 1 is disposed inside the stator core 1.

  In this state, the first-stage resin mold is applied to the slot 1a (step S3). Thereby, the slot resin part 5 is formed in the slot part 1a, and the division | segmentation core 2 is integrated (temporarily fixed) with high precision. After the first-stage resin molding, as shown in FIG. 13, the outer periphery restraining jig 10 and the inner intrusion prevention jig 8 are removed from the stator core 1.

  Thereafter, as shown in FIG. 14, the temporarily fixed stator core 1 is set in the frame mold 9, and the inner intrusion prevention jig 8 is disposed inside the stator core 1.

  In this state, a second-stage resin mold is applied to the outer periphery of the stator core 1 (step S4). Thereby, the frame resin part 6 which comprises the flame | frame of an electric motor is formed in the outer peripheral part of the stator core 1. FIG. Thereafter, the inner intrusion prevention jig 8 and the frame mold 9 are removed from the stator core 1, and finishing work such as processing of the end surface of the frame resin portion 6 is performed as necessary, as shown in FIG. Complete stator.

  In such a stator manufacturing method, during the first-stage resin molding, the convex portion 10a provided in the outer peripheral restraining jig 10 is fitted into the concave portion 2c provided in each core back portion 2a. Compared to the first embodiment, the inner peripheral roundness of the stator core 1 can be improved.

In addition, the shape of the recessed part 2c is not limited to V shape, Other shapes may be sufficient if it is a shape which can be positioned. Moreover, the shape of the convex part 10a is also changed according to the shape of the concave part 2c.
Moreover, the number of the recessed parts 2c provided in each divided core 2 is not limited to one, and may be two or more as long as positioning is possible.

Embodiment 3 FIG.
Next, FIG. 15 is a sectional view showing a state during the manufacture of the stator of the electric motor according to the third embodiment of the present invention. In this example, the split cores 2 are connected by the thin connecting portion 13. Such a stator core structure is disclosed in, for example, Japanese Patent Application Laid-Open No. 11-220844. In the conventional stator manufacturing method, both ends of the coupling body of the split core 2 in FIG. 15 are welded. In this third embodiment, the stator core 1 is formed by bending the coupling body in FIG. Then, both ends are not welded, and a two-stage resin mold is applied as in the first embodiment.

Even in such a stator manufacturing method, it is possible to improve the roundness of the inner circumference while eliminating the need for welding for fixing the split core 2, and it is not necessary to use an inner diameter restraining jig having protrusions on the outer circumference. Therefore, the productivity of the stator can be improved.
Moreover, since the split core 2 is connected in advance by the connecting portion 13, the formation of the stator core 1 is easy, and the productivity is improved.

  For example, the same effect can be obtained by using a core structure as disclosed in Japanese Patent Application Laid-Open No. 2000-201458, and it is possible to improve the adhesion at the joint and the inner circumference roundness.

  Here, as described above, the cause of the cogging torque is the gap generated between the divided cores 2. FIG. 16 shows the results of measurement by the inventors of the relationship between the gap amount between the divided cores 2 and the cogging torque. FIG. 16 shows the experimental results in the case where a gap is generated at one location of the core dividing portion in the permanent magnet rotating electric machine having the cross-sectional shape as shown in FIG. In addition, the horizontal axis is the gap amount of the core divided portion / the air gap length (the gap amount between the stator and the rotor), and the vertical axis is the cogging torque when a gap amount of 10% of the air gap length occurs. Is the cogging torque ratio.

  From FIG. 16, it can be seen that in order to reduce the cogging torque, it is necessary to reduce the gap amount between the divided cores 2 as much as possible. It is particularly preferable that the gap amount be 5% or less of the air gap length. According to the stator manufacturing method as shown in the first to third embodiments, the gap amount can be 5% or less of the air gap length, and the cogging torque generated by the divided portion gap can be reduced. Is possible.

  In addition, the influence of the gap between the divided cores 2 becomes obvious particularly with a small motor. Therefore, the present invention is effective for a small motor, particularly a small permanent magnet rotating electric machine, for reducing the cogging torque of a permanent magnet type synchronous motor having 4 to 10 rotor magnet poles and 3 to 12 stator slots. Useful.

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described. In this example, the resin material of the slot resin portion 5 and the resin material of the frame resin portion 6 are different. Specifically, the slot resin portion 5 is made of a resin material having high thermal conductivity (for example, an epoxy resin containing a material having good thermal conductivity such as alumina or crystalline silica) or a resistance to reducing the temperature rise of the motor. Epoxy resin with good voltage performance is used. In addition, the frame resin portion 6 has a resin material (BMC mold or the like) having a thermal contraction rate smaller than that of the slot resin portion 5 in order to eliminate processing after molding, or the slot resin portion 5 in order to prevent chipping of the mold. Also, a resin material with high strength is used. As a result, the motor temperature can be reduced and the frame strength can be improved.

  The present invention can be applied not only to an electric motor but also to a generator.

It is sectional drawing of the stator of the electric motor by Embodiment 1 of this invention. It is process drawing which shows the manufacture procedure of the stator of FIG. It is sectional drawing which shows the state which mounted | worn with the coil | winding part to the division | segmentation core of FIG. It is sectional drawing which shows the state which formed the stator core with the division | segmentation core of FIG. It is sectional drawing which shows the state which mounted | worn the outer periphery restraint jig | tool and the inner side penetration prevention jig | tool with the stator core of FIG. It is sectional drawing which shows the state which gave the resin mold in the slot part of FIG. 5, and removed the outer periphery restraint jig | tool and the inner side penetration prevention jig | tool. It is sectional drawing which shows the state which set the stator core of FIG. 6 in the metal mold | die for flame | frames. It is sectional drawing of the permanent magnet rotary electric machine using the stator of FIG. It is sectional drawing of the stator of the electric motor by Embodiment 2 of this invention. It is sectional drawing which shows the state which mounted | worn with the coil | winding part to the division | segmentation core of FIG. It is sectional drawing which shows the state which formed the stator core with the division | segmentation core of FIG. It is sectional drawing which shows the state which mounted | wore the outer periphery restraint jig | tool and the inner side penetration prevention jig | tool with the stator core of FIG. It is sectional drawing which shows the state which gave the resin mold in the slot part of FIG. 12, and removed the outer periphery restraint jig | tool and the inner side penetration prevention jig | tool. It is sectional drawing which shows the state which set the stator core of FIG. 13 in the metal mold | die for flame | frames. It is sectional drawing which shows the state in the middle of manufacture of the stator of the electric motor by Embodiment 3 of this invention. It is a graph which shows the result of having measured the relationship between the clearance gap between division | segmentation cores of FIG. 8, and cogging torque.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Stator core, 1a Slot part, 2 division | segmentation core, 2a Core back part, 2b Teeth part, 2c recessed part, 4 winding part, 5 slot resin part, 6 Frame resin part, 7, 10 Outer periphery restraint jig, 8 Inside Intrusion prevention jig, 10a convex portion, 11 rotor core, 12 permanent magnet.

Claims (7)

Attaching a winding part to each of the tooth parts of the plurality of split cores each having a core back part and a tooth part;
The split cores are arranged in an annular shape to form a stator core, and an outer peripheral restraining jig for restraining the split core is attached to the outer peripheral portion of the stator core in a state where the core back portions adjacent to each other are joined together. Process,
The resin molded facilities in a plurality of slots formed between the teeth, the step of integrating the divided cores, and remove the outer peripheral restraining jigs from the stator core, the outer periphery of the stator core the resin mold was facilities, a stator manufacturing method of a rotating electric machine characterized in that it comprises a step of forming a frame.   The cylindrical inner intrusion prevention jig for preventing intrusion of mold resin into the inner side of the stator core is disposed inside the stator core when the resin mold is applied. Of manufacturing a stator of a rotating electric machine.   When mounting the outer peripheral restraining jig on the outer peripheral portion of the stator core, the convex portion provided on the outer peripheral restraining jig is fitted into the concave portion provided on each core back portion. A stator manufacturing method for a rotating electrical machine according to claim 1 or 2.   The resin material used when resin molding is performed in the slot portion is different from the resin material used when resin molding is applied to the outer peripheral portion of the stator core. A method for manufacturing a stator of a rotating electric machine according to item 1.   The said core back parts adjacent to each other are joined by non-welding, The stator manufacturing method of the rotary electric machine of any one of Claim 1- Claim 4 characterized by the above-mentioned. The dimensions of the gap between the divided cores claim from claim 1, characterized in that less than 5% of the air gap length between the inner peripheral surface and the permanent magnets of the stator core 5 adjacent to each other any one stator manufacturing method of a rotating electric machine mounting serial in Section up. The number of permanent magnets is 4 to 10, a stator of a rotary electric machine of the mounting serial to any one of claims 1 to number of the slot may be equal to 3 to 12 to claim 6 Manufacturing method .

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