JP2009044788A - Split stator core, split stator, stator and manufacturing method of the stator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the characteristics of a motor and reduce iron loss by devising the shape of a split stator core, by reducing the nonuniformity in the magnetic flux density. <P>SOLUTION: The split stator core circularly disposed to form a stator is provided with a back yoke portion and a teeth portion, protruding from the back yoke portion toward the inside of the stator. Both the surfaces in the stator circumferential direction of the back yoke portion are used as bonding end surfaces to the split stator cores adjacent in a circumferential direction, and an angle &alpha;, formed by the bonding end surfaces of both ends of the circumferential direction, is made larger than an angle &beta; obtained by dividing 360&deg; by the number of split stators configuring the stator. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a divided stator core, a divided stator using the divided stator core, a stator formed by assembling the divided stator, and a method for manufacturing the stator, and reduces iron loss in the divided stator core and improves motor characteristics. .

  2. Description of the Related Art Conventionally, in a motor, a stator core (iron core) used for a stator disposed on the outer periphery of a rotor has a divided stator core obtained by dividing a ring-shaped stator core at a predetermined angle for reasons such as ease of winding and improvement of occupancy. Often used.

The divided stator core is usually arranged in an annular shape with a coil wound around it, and a bake ring is fitted around the outer periphery of these divided stator cores and fastened to form a stator.
That is, the shrink bake ring is preheated and expanded, and is fitted onto the outer peripheral surface of the split stator core arranged in an annular shape in this state. The surface is pressed by baking bakeling, and the divided stator cores are fastened.

JP, 2005-354838, A (patent documents 1) is provided as a stator which forms the above-mentioned division stator core integrally. As shown in FIG. 9A, the stator 1 of Patent Document 1 is configured by connecting a plurality of stator core components 2 along the circumference of the rotor core 3 in the stator circumferential direction.
As shown in FIG. 9 (B), the stator core component 2 has a yoke portion 2a, a teeth portion 2b protruding from the yoke portion 2a toward the inner peripheral side, and is opposed to the yoke portion 2a across the teeth portion 2b. The provided collar part 2c and the coil 2d wound around the teeth part 2b are provided. The stator 1 is arranged in such a manner that the end surface of the yoke portion 2a in the stator circumferential direction is annularly continuous in the stator circumferential direction with the joint end surface 2e, and the stator core components 2 are fastened together.

JP 2005-354838 A

The magnetic flux generated by the coil 2d wound around the tooth portion 2b flows through the both side portions of the yoke portion 2a projecting from the tooth portion 2b in the circumferential direction of the stator to the adjacent yoke portion 2a. Since the magnetic flux takes the shortest distance path, the magnetic flux density on the inner peripheral side 2f is locally increased at the joint portion between the adjacent yoke portions 2a, and the magnetic flux density becomes non-uniform.
In the core of magnetic material, the loss of electric energy, that is, the iron loss, which causes the motor characteristics to deteriorate, is proportional to the magnetic flux density about 1.6. Therefore, when the magnetic flux is not uniform, the iron loss increases and the magnetic flux is saturated and a leakage magnetic flux may be generated. In the stator 1 of Patent Document 1, there is a problem that the motor characteristics are likely to deteriorate.

  This invention is made | formed in view of the said problem, and makes it a subject to eliminate a magnetic flux density nonuniformity by reducing the shape of a division | segmentation stator core, to reduce an iron loss, and to improve a motor characteristic. .

In order to solve the above problems, the present invention is a split stator core that is arranged in an annular shape to form a stator,
A back yoke portion, and a teeth portion projecting inward from the back yoke portion into the stator, and the end surfaces in the radial direction at both ends of the stator in the circumferential direction of the back yoke portion are joined end surfaces to the divided stator cores adjacent in the circumferential direction; And
The split stator core is characterized in that the angle α formed by the joint end faces at both ends in the circumferential direction is set to be larger than the angle β obtained by dividing 360 degrees by the number of split stators constituting the stator.

With the above configuration, when a plurality of divided stator cores are arranged in an annular shape and integrally fixed by pressing the outer periphery of the divided stator cores inward by baking bake ring, the outer peripheral side of the joining end surface of the adjacent back yoke part They are in contact with each other and the inner peripheral side of the joint end surface is not in contact, or the entire joint end surface is in contact, and the contact pressure on the inner peripheral side contact surface is smaller than the contact pressure on the outer peripheral contact surface of the joint end surface. It becomes a state.
As described above, a gap is provided on the inner peripheral side of the joining end surface of the back yoke portion where the magnetic flux density is locally increased in the contact state, or the contact pressure on the inner peripheral contact surface is smaller than that on the outer peripheral side. As a result, the magnetic flux is dispersed on the outer peripheral side with which the joining end face is in contact, so that the non-uniformity of the magnetic flux in the back yoke portion can be eliminated and the iron loss can be reduced. Therefore, the leakage magnetic flux can be reduced, and the motor characteristics can be improved.

The divided stator core may be formed of a dust magnetic material or a laminated steel plate.
When the divided stator core is made of a powder magnetic material, it can be easily manufactured by three-dimensional molding, so that workability is good and cost can be reduced. Furthermore, since the split stator core can be finely pulverized when the motor is discarded, the split stator core and the coil can be easily separated, and the recyclability is high.
On the other hand, when the split stator core is composed of laminated steel plates, the laminated steel plates can be manufactured by punching the steel plates, so that they can be manufactured easily and at low cost.

Furthermore, the present invention provides a split stator in which a coil is formed by winding a winding around a tooth portion of the split stator core.
Provided is a stator for a motor that is arranged in an annular shape, wherein back yoke portions of the divided stator cores adjacent in the circumferential direction are joined to each other at the joining end surfaces. Yes.

It is preferable that the joint end faces are brought into contact over the entire surface, and the contact pressure on the inner peripheral side contact surface is smaller than the contact pressure on the outer peripheral side contact surface, or
It is preferable that the outer peripheral side of the joining end surface is brought into contact with the contact end portion while the inner peripheral side of the joining end surface is formed as a non-contact portion with a gap.

  With the above configuration, the inner peripheral side of the joining end face is not contacted with a gap, or the contact pressure on the inner peripheral side is smaller than the outer peripheral side, and the magnetic flux of the coil is dispersed on the outer peripheral side of the joining end face. By passing, the non-uniformity of the magnetic flux in the split stator core can be eliminated and the iron loss can be reduced, and the portion where the magnetic flux density is locally increased is eliminated, so that the magnetic flux is not saturated and the leakage magnetic flux can be reduced. The motor characteristics can be improved.

  The length of the non-contact portion on the inner peripheral side of the joint end surface in the stator radial direction is 40% to 60% of the length of the joint end surface in the stator radial direction, and the circumferential direction of the inner peripheral end of the non-contact portion Is preferably 0.5 mm to 1 mm.

Since the circumferential dimension of the inner peripheral end of the non-contact portion is 0.5 mm to 1 mm, the magnetic flux hardly flows in the non-contact portion and the magnetic flux easily flows in the contact portion. The magnetic flux flowing on the side can be dispersed on the outer peripheral side, and there is no portion with a high magnetic flux density locally, and iron loss can be reduced.
If the length of the non-contact portion in the stator radial direction is smaller than 40% of the length of the joint end face in the stator radial direction, the magnetic flux is not dispersed to the outer peripheral side. Since the outer peripheral side of the joining end surface which is a passage is narrowed, the motor characteristics are reduced.

Furthermore, the present invention provides a method for manufacturing the stator,
The split stator core is arranged in an annular shape, and the outer peripheral ends of the joint end surfaces of the adjacent split stator cores are brought into contact with each other,
Provided is a stator manufacturing method in which an outer ring for shrink fitting is fitted on the outer peripheral surface of the back yoke portion assembled in an annular shape, the outer ring is shrinked to reduce the diameter, and the joining end faces are joined. is doing.

  As described above, the split stator core of the present invention has a back yoke portion whose magnetic flux density is locally increased when the joint end surfaces of the back yoke portions are in contact with each other when the stator is fastened in an annular shape. By providing a gap on the inner peripheral side of the joint end surface, or by making the contact pressure of the inner peripheral side contact surface smaller than that on the outer peripheral side, the magnetic flux is dispersed on the outer peripheral side where the joint end surface is in contact, and in the back yoke part The non-uniformity of the magnetic flux can be eliminated and the iron loss can be reduced, and the magnetic flux is not saturated on the inner peripheral side of the joining end face, so that the leakage magnetic flux can be reduced and the motor characteristics can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 7 show a first embodiment of the present invention.

  The divided stator 10 of the first embodiment includes a divided stator core 11, an insulating resin coating 12 that is externally fitted to the divided stator core 11, and a tooth portion 11 a of the divided stator core 11 with an insulating resin coating 12 interposed therebetween. And a coil 14 formed by winding a winding. The divided stators 10 are sequentially arranged in an annular shape, and an outer ring 20 for shrinkage is fitted and fixed to the outer peripheral surface to form a stator 30. The stator 30 is arranged around the rotor 40 to constitute a motor 50.

As shown in FIG. 3A, the divided stator core 11 includes a back yoke portion 11b, a tooth portion 11a protruding from the back yoke portion 11b into the stator 30 and an inner peripheral end of the tooth portion 11a. It consists of a flange 11c protruding in the direction D2.
Both end faces in the stator circumferential direction D2 of the back yoke portion 11b are joined end faces 11d and 11d with the divided stator core 11 adjacent to the stator circumferential direction D2, and the joined end faces 11d and 11d are joined together to form the stator 30. The back yoke portion 11b and the flange portion 11c have the same height in the stator axial direction D3 as that of the tooth portion 11a.

The angle α formed by the joining end surfaces 11d and 11d of the back yoke portion 11b is a line connecting the outer peripheral ends 11g and 11g of both joining end surfaces 11d and 11d of the back yoke portion 11b and the stator center O as shown in FIG. Is larger than the angle β obtained by dividing 360 ° by the number of the divided stators 10 constituting the stator 30. In the present embodiment, the number of the divided stators 10 is 18, β is 20 degrees, and α is 21 degrees.
The divided stator core 11 is integrally formed by pressurizing and compressing a dust magnetic material and then performing heat treatment. The split stator core 11 may be formed from a steel plate laminate.

As shown in FIG. 4, the insulating resin coating 12 includes a rectangular cylindrical tooth coating 12 a that covers the outer peripheral surface of the tooth 11 a, and a back yoke coating 12 b from the outer peripheral end of the tooth coating 12 a. From the inner peripheral end, a collar covering portion 12c projects in a bowl shape. The insulating resin coating 12 has a thickness of 0.2 mm.
In the present embodiment, the insulating resin coating 12 is molded as molded products 12-1 and 12-2 that are divided into two parts along the axis in the stator radial direction D <b> 1, and is externally fitted to the divided stator core 11.
Instead of forming the insulating resin coating 12 separately from the divided stator core 11 and attaching it to the divided stator core 11, the insulating coating layer 12 may be molded to the divided stator core 11 to form an insulating coating layer.

As shown in FIG. 1 and FIG. 7, the stator 30 has the split stator 10 arranged in an annular shape, and an outer ring 20 for shrinking is fitted on the outer peripheral surface thereof and fastened integrally.
As shown in FIGS. 7A and 7B, the split stator 10 arranged in an annular shape is brought into contact with the outer peripheral side of the joint end surface 11d of the split stator core 11 adjacent to the stator circumferential direction D2 as a contact portion 11e. On the other hand, the inner peripheral side of the joining end surface 11d is a non-contact portion 11f with a gap.
The length L1 of the non-contact portion 11f in the stator radial direction D1 is 50% of the length L2 of the joint end surface 11d in the stator radial direction D1. In addition, the dimension length L3 in the stator circumferential direction D2 at the inner peripheral end of the non-contact portion 11f is 0.8 mm, and the magnetic flux passes through the non-contact portion 11f although the magnetic flux density is low.

  The outer ring 20 for shrink shrinkage is a metal ring, and the inner peripheral diameter of the outer ring 20 for shrink shrink is smaller than the outer peripheral diameter of the split stator core 11 arranged in an annular shape at room temperature. And it is set as the diameter which can be fitted in the outer periphery of the division | segmentation stator core 11 arrange | positioned in the annular | circular shape in the state expanded by heating.

Next, a method for manufacturing the split stator 10 and the stator 30 will be described.
First, as shown in FIG. 4, the divided stator core 11 is assembled by sandwiching the divided insulating resin coatings 12-1 and 12-2 from both sides. Specifically, the tooth portion 11a is fitted into the tooth covering portion 12a, and the flange covering portion 12c and the back yoke covering portion 12b are covered on the flange portion 11c and the back yoke portion 11b.

  A coil 14 is wound around the tooth portion 11a of the divided stator core 11 covered with the insulating resin coating 12 to obtain a divided stator 10 as shown in FIG.

Next, as shown in FIGS. 5A and 5B, the divided stator 10 around which the coil 14 is wound is arranged in an annular shape while contacting the outer peripheral end 11g of the joining end surface 11d.
Thereafter, the shrink ring outer ring 20 is preliminarily heated and expanded, and the inner peripheral diameter thereof is made larger than the outer peripheral diameter of the divided stator 10 connected in an annular shape. In this state, as shown in FIG. The outer ring 20 is externally fitted to the outer periphery of the split stator 10 connected in an annular shape.

  The outer ring 20 for shrinking shrinkage is reduced in diameter by natural cooling, and the outer ring 20 for shrinking shrinkage is directed toward the stator center O with the outer peripheral surface of the back yoke portion 11b of the divided stator core 11 in the process of reducing the diameter. Press inward. Then, as shown in FIGS. 7A and 7B, the outer peripheral side of the joining end surface 11d of the back yoke portion 11b is brought into close contact with each other to become the contact portion 11e, and a gap is formed between the inner peripheral sides even after the diameter reduction. It exists and becomes the non-contact part 11f. In this state, the adjacent divided stator cores 11 and the outer ring 20 for shrinkage are integrally fixed to form a stator 30.

  In the stator 30 having the above-described configuration, the magnetic flux B generated by the coil 14 of each split stator 10 passes through both sides on the back yoke portion 11b side, and is adjacent to both sides in the stator circumferential direction D2 from each joint end surface 11d, 11d. Flows to the joining end surfaces 11d and 11d of the back yoke portion 11b. At that time, most of the magnetic flux B passing through the inner peripheral side of the joint end face 11d is provided at the inner peripheral side of the joint end face 11d, which is a position corresponding to the path of the magnetic flux and locally has a high magnetic flux density. Can pass through the contact portion 11e on the outer peripheral side, and the magnetic flux B is dispersed, so that nonuniformity of the magnetic flux density can be eliminated and saturation of the magnetic flux B can be prevented. Therefore, reduction of electric energy, that is, iron loss can be reduced, and motor characteristics can be improved.

Furthermore, when the divided stator core 11 is made of a powder magnetic material, it can be easily manufactured by three-dimensional molding, so that workability is good and cost can be reduced.
In addition, since the insulating resin coating layer formed on the coil winding portion of the divided stator core is formed of a molded product, the insulating resin coating bodies 12-1 and 12-2 are only externally fitted to the divided stator core 11 at necessary locations. Thus, the insulating resin layer can be easily provided.

8A and 8B show a second embodiment of the present invention.
In the stator 300 according to the second embodiment, the split stator cores 11 are arranged in an annular shape and fastened, the joint end faces 11d of the back yoke portions 11b of the adjacent split stator cores 11 are brought into contact over the entire surface, and contact on the outer peripheral side is made. The configuration in which the contact pressure of the contact surface 11i on the inner peripheral side is smaller than the contact pressure of the surface 11h is different from that of the first embodiment.

  With the above configuration, the contact end surface of the contact surface 11i on the inner peripheral side of the joint end surface 11d, which is a position that hits the path of the magnetic flux and has a locally high magnetic flux density, is smaller than the contact surface 11h on the outer peripheral side. Most of the magnetic flux B that has passed through the inner peripheral side of 11d passes through the contact surface 11h on the outer peripheral side, and the magnetic flux B is dispersed, so that the nonuniformity of the magnetic flux density can be eliminated and the saturation state of the magnetic flux B Can be prevented. Therefore, reduction of electric energy, that is, iron loss can be reduced, and motor characteristics can be improved.

  The present invention is not limited to the above-described embodiments, and includes various forms within the scope of the claims of the present invention.

It is a perspective view showing a motor, It is a perspective view which shows the division | segmentation stator of this invention. It is a figure which shows the division | segmentation stator core of this invention, (A) is a perspective view, (B) is a figure explaining the angle which a joining end surface makes. It is a perspective view which coat | covers an insulation resin layer on a division | segmentation stator core. It is a figure which shows the manufacturing process of a stator, (A) is a top view of the state which has arrange | positioned the division | segmentation stator in the annular | circular shape, (B) is the figure which expanded the principal part of (A). It is a figure which shows the manufacturing process of a stator, and is a top view which shows the state which has arrange | positioned the outer ring for shrinkage | fitting on the outer periphery of the division | segmentation stator arrange | positioned in the annular | circular shape. It is a figure which shows the manufacturing process of a stator, (A) is a top view which shows the state which fitted the outer ring for shrinkage to the outer periphery of the division | segmentation stator arrange | positioned circularly, (B) is the principal part of (A). FIG. It is a figure which shows 2nd Embodiment of this invention, (A) is a top view which shows the state which fitted the outer ring for shrinkage | fitting on the outer periphery of the division | segmentation stator arrange | positioned circularly, (B) is (A). It is the figure which expanded the principal part. It is a figure which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Split stator 11 Split stator core 11a Teeth part 11b Back yoke part 11e Contact part 11f Non-contact part 12 Insulating resin coating 14 Coil 20 Outer ring 30 for shrink shrinkage, 300 Stator 50 Motor D1 Stator radial direction D2 Stator circumferential direction D3 Stator Axial direction

Claims (8)

A split stator core arranged in an annular shape to form a stator,
A back yoke portion, and a teeth portion projecting inward from the back yoke portion into the stator, and the end surfaces in the radial direction at both ends of the stator in the circumferential direction of the back yoke portion are joined end surfaces to the divided stator cores adjacent in the circumferential direction; And
An angle α formed by the joining end surfaces at both circumferential ends is set to be larger than an angle β obtained by dividing 360 degrees by the number of divided stators constituting the stator.   The split stator core according to claim 1, wherein the split stator core is formed of a powder magnetic material or a laminated steel plate.   A split stator in which a coil is formed by winding a winding around the teeth portion of the split stator core according to claim 1.   A stator of a motor formed by arranging the split stator according to claim 3 in an annular shape, wherein the back yoke portions of the split stator core adjacent in the circumferential direction are joined to each other at the joint end face. Stator characterized by.   The stator according to claim 4, wherein the joining end faces are brought into contact over the entire surface, and the contact pressure on the inner peripheral contact surface is smaller than the contact pressure on the outer peripheral contact surface.   5. The stator according to claim 4, wherein the outer peripheral side of the joint end surface is brought into contact to form a contact portion, while the inner peripheral side of the joint end surface is formed as a non-contact portion with a gap.   The length of the non-contact portion on the inner peripheral side of the joint end surface in the stator radial direction is 40% to 60% of the length of the joint end surface in the stator radial direction, and the circumferential direction of the inner peripheral end of the non-contact portion The stator according to claim 6, wherein the dimension is set to 0.5 mm to 1 mm. A stator manufacturing method according to claim 4 to claim 7,
The split stator core is arranged in an annular shape, and the outer peripheral ends of the joint end surfaces of the adjacent split stator cores are brought into contact with each other,
A stator manufacturing method in which an outer ring for shrinking is externally fitted on the outer peripheral surface of the back yoke portion assembled in an annular shape, the outer ring is shrinked to reduce the diameter, and the joining end faces are joined.

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