JP2021136756A - Positioning method of laminated iron core - Google Patents

Abstract

To provide a positioning method of a laminated iron core capable of easily positioning a laminated iron core.SOLUTION: The positioning method of a laminated iron core includes the steps of: loosely fitting an insertion part 42 of a jig 40 into a center hole 22; rotating the insertion portion 42 around the central axis of the central hole 22 with respect to a rotor core 20. With this, in the radial direction of the rotor core 20, the inner peripheral surface 22a of the center hole 22 and the outer peripheral surface 44a of the ridge 44 are brought into contact with each other to thereby determine the position of each steel plate 21 in the radial direction.SELECTED DRAWING: Figure 6

Description

The present invention relates to a method for positioning a laminated iron core.

The rotor of a magnet-embedded motor is configured by laminating a plurality of steel plates, and is accommodated in a rotor core having a center hole and a magnet accommodating hole and each magnet accommodating hole, and is housed in each magnet accommodating hole with respect to the rotor core via a thermosetting resin. It has a fixed magnet.

In the manufacture of such a rotor, the magnet is fixed to the rotor core by resin molding, that is, by filling the magnet accommodating hole with resin and thermosetting the resin.

Patent Document 1 discloses a rotor core holding jig (hereinafter, referred to as a holding jig) that enhances the stacking accuracy of the rotor core by positioning each steel plate at the time of resin molding. The holding jig has a cylindrical portion that fits into the center hole of the rotor core, and a fitting key that fits into a key formed on the inner peripheral surface of the center hole. A part of the fitting key is made of a resin having a larger coefficient of thermal expansion than a steel plate.

At the time of resin molding, the resin portion of the fitting key expands more thermally than the other portions due to the heating of the holding jig, so that the fitting key restrains the key of the rotor core. As a result, each steel plate is positioned to improve the stacking accuracy of the rotor core. On the other hand, after the resin molding, the resin portion is heat-shrinked more than the other portions, so that the fitting key releases the key of the rotor core.

Japanese Unexamined Patent Publication No. 2007-20242

By the way, in the above holding jig, when separating the rotor core and the holding jig after resin molding, it is necessary to wait until the fitting key releases the key of the rotor core, that is, until the temperature of the fitting key drops. .. Therefore, it takes time and effort to position a laminated iron core such as a rotor core.

An object of the present invention is to provide a method for positioning a laminated iron core that can be easily positioned.

The method for positioning the laminated iron core for achieving the above object is a method for positioning the laminated iron core, which is configured by laminating a plurality of steel plates and positions each of the steel plates in the laminated iron core having a center hole. After the jig is loosely fitted in the hole, the jig and the laminated iron core are rotated relative to each other about the central axis of the central hole, whereby the inner peripheral surface of the central hole and the laminated iron core are rotated in the radial direction of the laminated iron core. Each of the steel plates is positioned in the radial direction by bringing them into contact with the outer peripheral surface of the jig.

According to this method, positioning of each steel sheet in the radial direction is performed by relatively rotating the jig loosely fitted in the center hole and the laminated iron core. Since the jig is loosely fitted in the center hole, the jig can be easily attached to and detached from the laminated iron core. Further, the positioning of each steel plate in the radial direction is performed by a simple method of relatively rotating the jig and the laminated iron core. Therefore, the laminated iron core can be easily positioned.

The perspective view which shows the rotor in one Embodiment. A vertical sectional view showing a rotor. A vertical sectional view showing a rotor core into which an insertion portion is inserted. The cross-sectional view which shows the rotor core in the state where the insertion part is in the insertion position. An enlarged cross-sectional view showing an enlarged portion A of FIG. An enlarged cross-sectional view showing the rotor core with the insertion part in the regulated position. The vertical sectional view which shows the rotor core in the state which the magnet is accommodated in the magnet accommodating hole. The vertical sectional view which shows the rotor core in the state which the magnet accommodating hole is filled with resin. An enlarged cross-sectional view showing a rotor core in a state where the insertion portion of the first modification is in the insertion position. An enlarged cross-sectional view showing a rotor core in a state where the insertion portion of the first modification is in the regulated position. FIG. 5 is a cross-sectional view showing a rotor core in a state where the insertion portion of the second modification is inserted into the center hole.

Hereinafter, with reference to FIGS. 1 to 8, one embodiment in which the method for positioning the laminated iron core is embodied as the method for positioning the rotor core of the rotary electric machine will be described.
First, the rotor 10 of the rotary electric machine will be described.

As shown in FIGS. 1 and 2, the rotor 10 includes a cylindrical rotor core 20 having a central hole 22. A shaft (not shown) is inserted through the center hole 22. The rotor core 20 is formed by laminating a plurality of steel plates 21. The steel plate 21 is formed by punching, for example, a silicon steel plate.

Hereinafter, the direction in which the central axis C of the central hole 22 extends is referred to as an axial direction. Further, the circumferential direction of the rotor core 20 centered on the central axis C is simply referred to as a circumferential direction, and the radial direction of the rotor core 20 centered on the central axis C is simply referred to as a radial direction. Further, in FIG. 1, the side facing clockwise is defined as one side in the circumferential direction, and the side facing counterclockwise is referred to as the other side in the circumferential direction. The stacking direction of the steel plates 21 coincides with the axial direction.

As shown in FIG. 1, most of the central hole 22 has a circular shape located on a virtual circle centered on the central axis C.
A pair of key portions 23 projecting inward in the radial direction are provided on the inner peripheral surface 22a of the central hole 22 over the entire axial direction. The pair of key portions 23 are provided so as to face each other in the radial direction. The cross-sectional shape of the key portion 23 orthogonal to the axial direction is substantially square. The tip of the key portion 23 is located inside the virtual circle in the radial direction.

Of the inner peripheral surface 22a of the central hole 22, recessed portions 24 recessed outward in the radial direction are provided on both sides of each key portion 23 in the circumferential direction over the entire axial direction.
A plurality of magnet accommodating holes 25 are provided in a portion of the rotor core 20 on the outer peripheral side of the central hole 22 at intervals in the circumferential direction. More specifically, the rotor core 20 is provided with eight pairs of magnet accommodating holes 25 adjacent to each other in the circumferential direction. The cross-sectional shape of the magnet accommodating hole 25 orthogonal to the axial direction is long. The pair of magnet accommodating holes 25 are located inward in the radial direction so as to be closer to each other.

As shown in FIG. 2, each magnet accommodating hole 25 accommodates a plate-shaped magnet 30 extending along the axial direction. The inside of each magnet accommodating hole 25 is filled with a resin 31 for fixing the magnet 30. In the present embodiment, the steel plates 21 are joined to each other by the resin 31. The resin 31 is preferably a thermosetting resin such as an epoxy resin.

Next, a method of manufacturing the rotor 10 including a method of positioning the rotor core 20 will be described.
First, the jig 40 for positioning the rotor core 20 will be described with reference to FIGS. 3 to 5.

As shown in FIG. 3, the jig 40 has a base portion 41 that supports the entire lower surface of the rotor core 20, and a substantially columnar insertion portion 42 that protrudes from the base portion 41 and is inserted into the central hole 22 of the rotor core 20. And have. The jig 40 is made of a metal material such as stainless steel.

An insertion hole 41a into which the base end of the insertion portion 42 is inserted is provided in the central portion of the base portion 41. A bearing 46 that rotatably supports the insertion portion 42 is provided in the insertion hole 41a.

The base end of the insertion portion 42 is connected to the output shaft of the servomotor M that rotationally drives the insertion portion 42. Therefore, the insertion portion 42 of the present embodiment is rotatably provided with respect to the base portion 41.

As shown in FIGS. 4 and 5, the insertion portion 42 has a columnar main body portion 43. The diameter of the main body 43 is smaller than the diameter of the central hole 22.
Further, the insertion portion 42 has a pair of ridges 44 that protrude outward from the main body portion 43 in the radial direction and extend along the protruding direction of the insertion portion 42. The ridge 44 extends over the entire protruding direction of the insertion portion 42. The pair of ridges 44 are provided on opposite sides of the central axis of the insertion portion 42.

As shown in FIG. 5, the outer peripheral surface 44a of the ridge 44 is curved along the inner peripheral surface 22a of the central hole 22 with substantially the same radius of curvature as the central hole 22. Therefore, the maximum value of the diameter of the insertion portion 42, that is, the distance between the outer peripheral surfaces 44a in the radial direction is substantially the same as the diameter of the central hole 22.

The first side surface 44b on one side of the ridge 44 in the circumferential direction is a plane orthogonal to the circumferential direction. The second side surface 44c on the other side of the ridge 44 in the circumferential direction is an inclined surface inclined so as to be located on the other side in the circumferential direction toward the inside in the radial direction.

The maximum width of the ridge 44 in the circumferential direction, that is, the maximum value of the distance between the first side surface 44b and the second side surface 44c is smaller than the maximum value of the opening width in the circumferential direction of the recess 24.
Further, the insertion portion 42 has a pair of groove portions 45 provided adjacent to one side of each ridge 44 in the circumferential direction. The groove portion 45 is provided so as to be connected to the ridge 44. The groove portion 45 is recessed inward in the radial direction from the tip of the key portion 23. The bottom surface 45a of the groove 45 is curved along the inner peripheral surface 22a of the central hole 22 with a radius of curvature smaller than that of the central hole 22.

The first side surface 45b on one side of the groove portion 45 in the circumferential direction and the second side surface 45c on the other side in the circumferential direction are both planes orthogonal to the circumferential direction.
The first side surface 44b of the ridge 44 and the second side surface 45c of the groove 45 are located on the same plane and are connected to each other.

Next, a method of manufacturing the rotor 10 will be described.
As shown in FIG. 3, first, the insertion portion 42 of the jig 40 is inserted into the center hole 22 of the rotor core 20. At this time, as shown in FIGS. 4 and 5, the insertion portion 42 is inserted into the central hole 22 with the ridge 44 facing the recess portion 24 adjacent to the key portion 23 on the other side in the circumferential direction.

Here, as described above, the diameter of the main body 43 is smaller than the diameter of the central hole 22. Further, the maximum width of the ridge 44 in the circumferential direction is smaller than the maximum value of the opening width in the circumferential direction of the recessed portion 24. Further, the groove portion 45 is recessed inward in the radial direction from the tip of the key portion 23. From the above, the insertion portion 42 is loosely fitted in the central hole 22. In other words, the insertion portion 42 is inserted into the central hole 22 with a gap between the insertion portion 42 and the inner peripheral surface 22a of the central hole 22. Hereinafter, the position of the insertion portion 42 with respect to the rotor core 20 at this time will be referred to as an insertion position.

As shown in FIG. 6, next, by driving the servomotor M, the insertion portion 42 is rotated about the central axis C from one side to the other side in the circumferential direction. As a result, the ridge 44 slides on the inner peripheral surface 22a of the central hole 22. Therefore, the outer peripheral surface 44a of the ridge 44 and the inner peripheral surface 22a of the central hole 22 come into contact with each other in the radial direction. Further, as the groove portion 45 moves from one side in the circumferential direction toward the other side, the first side surface 45b of the groove portion 45 and the side surface 23a on one side in the circumferential direction of the key portion 23 come into contact with each other in the circumferential direction. As a result, the rotation of the insertion portion 42 from one side in the circumferential direction to the other side is restricted. Hereinafter, the position of the insertion portion 42 with respect to the rotor core 20 at this time will be referred to as a regulation position.

When the insertion portion 42 in this embodiment is rotated, the outer peripheral surface of the rotor core 20 is supported by a jig (not shown). Thereby, the rotation of the insertion portion 42, more specifically, the rotation of the rotor core 20 by the frictional force generated between the insertion portion 42 and the rotor core 20 is regulated.

As shown in FIG. 7, next, the magnet 30 is accommodated in each magnet accommodating hole 25 of the rotor core 20.
Next, as shown in FIG. 8, the cal plate 50 is placed on the upper surface of the rotor core 20. The cal plate 50 has a plurality of injection ports 51 connected to each magnet accommodating hole 25. By injecting the resin 31 into each injection port 51, the resin 31 is filled inside each magnet accommodating hole 25 via the cal plate 50.

Next, the thermosetting resin 31 is thermally cured by heating the entire rotor core 20 with a heating device (not shown). As a result, the steel plates 21 are joined to each other and the magnet 30 is fixed to the rotor core 20.

The rotor 10 is manufactured in this way.
When removing the jig 40 from the rotor 10, the insertion portion 42 is rotated from the other side in the circumferential direction toward one side, so that the position of the insertion portion 42 is switched from the regulated position to the insertion position. ..

The operation of this embodiment will be described.
By rotating the insertion portion 42 of the jig 40 loosely fitted in the center hole 22 with respect to the rotor core 20, the outer peripheral surface 44a of the ridge 44 and the inner peripheral surface 22a of the center hole 22 come into contact with each other in the radial direction. As a result, each steel plate 21 is positioned in the radial direction. Since the insertion portion 42 is loosely fitted in the center hole 22, the jig 40 can be easily attached to and detached from the rotor core 20. Further, each steel plate 21 is positioned in the radial direction by a simple method of rotating the insertion portion 42 with respect to the rotor core 20 between the insertion position and the regulation position.

The effect of this embodiment will be described.
(1) After the insertion portion 42 of the jig 40 is loosely fitted in the center hole 22, the insertion portion 42 is rotated around the central axis C of the center hole 22 with respect to the rotor core 20 in the radial direction of the rotor core 20. The inner peripheral surface 22a of the central hole 22 and the outer peripheral surface 44a of the ridge 44 are brought into contact with each other to position each steel plate 21 in the radial direction.

According to such a method, the rotor core 20 can be easily positioned because the above-mentioned action is obtained.
(2) By rotating the insertion portion 42 with respect to the rotor core 20, the side surface 23a of the key portion 23 and the first side surface 45b of the groove portion 45 are brought into contact with each other in the circumferential direction of the rotor core 20 to position each steel plate 21 in the circumferential direction. I do.

According to such a method, since the positioning of each steel plate 21 in the circumferential direction is performed, the positioning accuracy of the rotor core 20 can be improved.
Further, in the rotor core 20, since the positions of the magnet accommodating holes 25 in the circumferential direction are aligned, the magnets 30 can be easily accommodated in the magnet accommodating holes 25. Therefore, the rotor core 20 can be easily manufactured.

(3) By rotating the insertion portion 42 of the jig 40 with respect to the rotor core 20, the inner peripheral surface 22a of the central hole 22 and the outer peripheral surface 44a of the ridge 44 are brought into contact with each other.
For example, when rotating the rotor core 20 with respect to the jig 40, it is necessary to hold the rotor core 20 and rotate each steel plate 21 collectively, which may complicate the device for holding the rotor core 20. be.

In this regard, according to the positioning method of the present embodiment, since the insertion portion 42 of the jig 40 is rotated with respect to the rotor core 20, it is possible to suppress the above-mentioned inconvenience. Therefore, the rotor core 20 can be positioned more easily.

<Change example>
This embodiment can be modified and implemented as follows. The present embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

In the first modification and the second modification shown in FIGS. 9 to 11 below, the same components as those in the above embodiment are designated by the same reference numerals, and the corresponding configurations are designated by the reference numerals of the above embodiment. By adding a code obtained by adding "100" and "200" to "**", duplicate explanations will be omitted.

In the present embodiment, the rotor core 20 is positioned by rotating the insertion portion 42 of the jig 40 with respect to the rotor core 20, but by rotating the rotor core 20 with respect to the jig 40, the rotor core 20 is positioned. Positioning may be performed. Further, the rotor core 20 may be positioned by rotating the jig 40 and the rotor core 20 in opposite directions in the circumferential direction.

As shown in FIGS. 9 and 10, the insertion portion 142 has a pair of columnar pins 60 that move along the circumferential direction in synchronization with the rotation of the main body portion 143 instead of the groove portions 45. There may be. According to this configuration, since the pin 60 comes into contact with the side surface 23a of the key portion 23 as the main body portion 143 rotates, an effect similar to the above-mentioned effect (2) can be obtained. Further, such a pin 60 may be provided at a position corresponding to a lightening hole provided, for example, through the rotor core 20 in the axial direction. Even with this configuration, by rotating the main body 143, the outer peripheral surface of the pin 60 and the inner peripheral surface of the lightening hole come into contact with each other, so that an effect similar to the above-mentioned effect (2) can be obtained. Can be done.

-The groove 45 can be omitted. Even with this configuration, it is possible to achieve an effect similar to the above-mentioned effect (1). Further, according to this configuration, as shown in FIG. 11, even in the rotor core 20 provided with the central hole 22 having no key portion 23, the outer peripheral surface of the ridge 244 and the inner circumference of the central hole 22 are provided. The surface 22a comes into contact with the surface 22a in the radial direction. Therefore, each steel plate 21 can be positioned in the radial direction. The central hole 22 of this modified example has three recessed portions 224 provided at intervals in the circumferential direction. The insertion portion 242 has three ridges 244 provided corresponding to each recess portion 224. As shown by the alternate long and short dash line in the figure, the ridge 244 slides on the inner peripheral surface 22a of the central hole 22 by rotating the insertion portion 242 in the circumferential direction.

-The servo motor M can be omitted. In this case, the insertion portion 42 may be rotated by engaging the tool or the like with the end portion of the insertion portion 42 and rotating the tool around the central axis C.

Even when the steel plates 21 are joined to each other by welding the outer peripheral surfaces of the rotor core 20, or when the steel plates 21 are crimped to each other in the axial direction, the method for positioning the laminated iron core in the present embodiment is applied. be able to.

-The method for positioning the laminated iron core of the present embodiment can also be applied to a rotor core configured by laminating a plurality of core blocks in which a plurality of steel plates 21 are crimped to each other.

-In the present embodiment, the positioning method of the rotor core 20 of the rotary electric machine is illustrated as an example of the positioning method of the laminated iron core, but the same method can be applied to the positioning method of the stator core of the rotary electric machine.

C ... Central axis M ... Servo motor 10 ... Rotor 20 ... Rotor core 21 ... Steel plate 22 ... Center hole 22a ... Inner peripheral surface 23 ... Key part 23a ... Side surface 24,224 ... Recessed part 25 ... Magnet accommodating hole 30 ... Magnet 31 ... Resin 40 ... Jig 41 ... Base portion 41a ... Insertion hole 42, 142, 242 ... Insertion portion 43, 143, 243 ... Main body portion 44, 144, 244 ... Protrusions 44a, 144a ... Outer peripheral surface 44b, 144b ... First side surface 44c , 144c ... 2nd side surface 45 ... Groove 45a ... Bottom surface 45b ... 1st side surface 45c ... 2nd side surface 46 ... Bearing 50 ... Cal plate 51 ... Injection port 60 ... Pin

Claims (3)

A method for positioning a laminated iron core, which is composed of laminating a plurality of steel plates and positions each of the steel plates in a laminated iron core having a central hole.
After the jig is loosely fitted in the central hole, the jig and the laminated iron core are relatively rotated around the central axis of the central hole, whereby the inner peripheral surface of the central hole is rotated in the radial direction of the laminated iron core. And the outer peripheral surface of the jig are brought into contact with each other to position each of the steel plates in the radial direction.
Positioning method of laminated iron core. By relatively rotating the jig and the laminated iron core, the inner peripheral surface of the central hole and the outer peripheral surface of the jig are brought into contact with each other in the circumferential direction of the laminated iron core in the circumferential direction of each of the steel plates. Perform positioning,
The method for positioning a laminated iron core according to claim 1. By rotating the jig with respect to the laminated iron core, the inner peripheral surface of the laminated iron core and the outer peripheral surface of the jig are brought into contact with each other.
The method for positioning a laminated iron core according to claim 1 or 2.

Images