JP2009044803A - 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 by enhancing the circularity of inside diameter of a stator, without complicating the shape of a bonding end face of a back yoke portion, by devising the shape of each of split stators in circularly disposing split stators and fastening them to form a ring-like stator. <P>SOLUTION: The split stator, disposed circularly to form a stator has a back yoke portion and a teeth portion protruding from the back yoke portion toward the inside of the stator, wherein an end face in the radial direction of both the faces of the stator circumferential direction of the back yoke portion is used as a bonding end face to a split stator core adjacent in the circumferential direction, and an angle α formed by the bonding end face of both the ends in the circumferential direction is set smaller than the angle β, obtained by dividing 360° by the number of split stators constituting the stator. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a split stator core, a split stator using the split stator core, a stator formed by assembling the split stator, and a method for manufacturing the stator, and an inner diameter perfect circle of the stator formed by arranging the split stator core in an annular shape It increases the degree and improves the 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 is a divided stator obtained by dividing a ring-shaped stator into a predetermined angle for reasons such as ease of winding and improvement in occupation rate. In many cases, the coils are wound around the core of each of the divided stators to form a coil in advance, and these divided stators are assembled in a ring shape.
Specifically, the divided stator core is arranged in an annular shape with a coil wound, 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.

  Since the motor characteristics are greatly affected by the gap (interval) between the stator core and the rotor, when the stator core is a split stator core, the inner circumference of each split stator core is not varied, and the inner diameter roundness of the stator is increased. It is desired to improve the characteristics of the motor by keeping the gap between each divided stator core and the rotor constant. Here, the roundness represents a difference between the maximum diameter and the minimum diameter.

A stator core disclosed in Japanese Patent Application Laid-Open No. 2005-354838 is provided as a stator in which a split stator core is integrally formed.
As shown in FIG. 8A, the stator core 1 is configured by connecting a plurality of stator core components 2 in the circumferential direction along the periphery of the rotor core 3. As shown in FIG. 8B, the stator core component 2 is opposed to the yoke portion 2a, the tooth portion 2b protruding from the yoke portion 2a toward the inner peripheral side, and the yoke portion 2a across the tooth portion 2b. 2c and a coil 2d wound around the tooth portion 2b. The stator core component 2 has a side surface 2e of the yoke portion 2a as a joint surface with the adjacent stator core component 2, and is arranged in the stator circumferential direction so as to be continuous in an annular shape, and the stator core components 2 are fastened together.

JP 2005-354838 A

  In the stator core 1 of Patent Document 1, when the stator core components 2 are fastened together by shrinkage, the side surfaces 2e of the yoke portions 2a that serve as the joint surfaces of the stator core components 2 are made to be slidable in the stator radial direction. For this reason, the stator core components 2 cannot be positioned, and the inner peripheral surface 2f of the stator core component 2 tends to vary in the radial direction. Therefore, there is a problem that the inner-surface roundness of the stator core 1 tends to be low, the gap between the stator core 1 and the rotor core 3 is not constant, and the motor characteristics are likely to deteriorate.

  On the other hand, the shape of the joining end surface of the back yoke portion that becomes the joining surface with the adjacent divided stator core, the shape that fits with the joining end surface of the adjacent divided stator core, and the contact position with the adjacent divided stator core at the fitting portion. It is conceivable to improve the inner diameter roundness of the stator by prescribing. However, in the divided stator core, there is a problem that the divided stator core has a complicated shape, a die manufacturing cost is increased and a manufacturing cost is increased, and an assembling property is liable to be deteriorated.

  The present invention has been made in view of the above problems, and when the divided stator cores are arranged in an annular shape and fastened to form a ring-shaped stator, the shape of the divided stator core is devised to join the back yoke portion. It is an object to increase the roundness of the inner diameter of the stator and improve the motor characteristics without complicating the shape of the end face.

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
In a state where the divided stator cores are arranged in an annular shape, the inner peripheral ends of the joint end faces of adjacent split stators are in contact with each other and separated from the outer peripheral side, and the angle α formed by these joint end faces is 360 degrees. The divided stator core is characterized in that it is set to be smaller than the angle β divided by the number of divided stators constituting.

With the above configuration, when the plurality of divided stator cores are arranged in an annular shape, the outer peripheral sides of the joining end surfaces of the adjacent back yoke portions do not contact each other, and the inner peripheral sides of the joining end surfaces contact each other. Positioning can be performed on the circumferential side. Further, when the outer periphery of the split stator core arranged in an annular shape is integrally fixed by pressing it inward by shrinking bamelling, it is arranged on the inner peripheral side of the joining end face that is in contact with the annularly arranged state. Stress is concentrated. On the inner peripheral side where stress is concentrated, adjacent split stator cores press against each other in the circumferential direction of the stator, so that each split stator core can be prevented from moving inwardly, and the misalignment of the split stator core can be minimized. it can.
Therefore, variation in the radial direction of the inner peripheral surface of the divided stator core can be prevented, and the roundness of the stator can be increased.
The inner diameter roundness of the stator of the present invention configured as described above can be 0.05 mm or less, and by achieving such roundness, the gap between the rotor and the stator is constant and the motor characteristics are improved. Can be made.

  Further, the split stator core of the present invention does not have a complicated shape, and the angle formed by the joining end faces is merely smaller than the angle obtained by dividing 360 degrees by the number of split stators. The change is easy, and it is not necessary to create a complicated mold, so that the manufacturing cost can be reduced, and the assembly is good when the stator is formed.

The divided stator core is preferably formed from 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 is a motor stator in which a divided stator that forms a coil by winding a winding around a tooth portion of the divided stator core is arranged in an annular shape,
The stator is characterized in that the joining end surfaces of the back yoke portions of the adjacent divided stator cores are brought into contact over the entire surface, and the contact pressure on the inner peripheral contact surface is larger than the contact pressure on the outer peripheral contact surface.

The magnetic flux generated by the coil wound around the teeth portion of the divided stator flows through both sides of the back yoke portion to the adjacent back yoke portion. Since the magnetic flux takes the shortest distance path, the magnetic flux density locally increases on the inner peripheral side of the joint end face of the back yoke portion, the magnetic flux density becomes non-uniform, and the loss of electric energy increases.
In the stator according to the present invention, the contact pressure on the inner peripheral side of the joint end surface of the back yoke portion is set larger than the contact pressure on the outer peripheral side. The magnetic flux that has passed through the inner peripheral side of the joint end face is dispersed on the outer peripheral side of the joint end face. Therefore, non-uniformity of magnetic flux in the back yoke portion can be eliminated and iron loss can be reduced, and the magnetic flux is not saturated on the inner peripheral side of the joint end surface, so that leakage magnetic flux can be reduced and motor characteristics are improved. Can do.

Furthermore, the present invention provides a method for manufacturing the stator,
The split stator core is arranged in an annular shape, the inner peripheral end of the joint end surface of the split stator core adjacent in the circumferential direction is contacted, and the outer peripheral side is positioned as non-contact,
An outer ring for shrinking is fitted on the outer peripheral surface of the back yoke portion arranged in an annular shape, and the outer ring is shrinked to shrink the diameter,
A non-contact outer peripheral side is also brought into contact in the diameter reduction step, and the entire surface of the joining end face is pressed.
In the state of the stator assembled with the divided stator, not only when the entire joining end surfaces of the adjacent divided stators are in close contact with each other, a gap may be formed between the joining end surfaces.

  As described above, according to the present invention, when the plurality of split stator cores are arranged in an annular shape, the outer peripheral side of the joining end surface of the adjacent back yoke part does not contact, and the inner peripheral sides contact each other. Positioning can be performed on the inner peripheral side of the joining end face. Furthermore, when the split stator cores arranged in an annular shape are fastened, stress concentrates on the inner peripheral side of the joint end surface, and the adjacent split stator cores are pressed against each other in the stator circumferential direction. It is possible to suppress the displacement of the split stator core to a minimum.

  Further, the split stator core of the present invention does not have a complicated shape, and the angle formed by the joining end faces is merely smaller than the angle obtained by dividing 360 degrees by the number of split stators. In addition, the manufacturing cost can be reduced because it is not necessary to create a complicated mold. Further, when the stator is formed, the joining end face is not complicated, so that the assemblability is good.

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

  The split stator 10 according to the present embodiment includes a split stator core 11, an insulating resin coating 12 that is externally fitted to the split stator core 11, and a tooth portion 11 a of the split stator core 11 via the insulating resin cover 12. 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.
End surfaces in the stator radial direction D1 at both ends of the stator circumferential direction D2 of the back yoke portion 11b are joined end surfaces 11d and 11d with the divided stator 10 adjacent to the stator circumferential direction D2, and the joined end surfaces 11d and 11d are joined to each other. A stator 30 is formed.
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.

As shown in FIG. 5A, the split stator core 11 is in contact with the inner peripheral ends 11g and 11g of the joining end surfaces 11d and 11d of the adjacent split stator 10 when the split stator 10 is arranged in an annular shape. The shape is set apart from the outer peripheral side. The angle α formed by the joining end surfaces 11d and 11d of the back yoke portion 11b connects the inner peripheral ends 11g and 11g of both the joining end surfaces 11d and 11d of the back yoke portion 11b and the stator center O as shown in FIG. The angle formed by the line, that is, the angle β obtained by dividing 360 degrees by the number of the divided stators 10 constituting the stator 30 is set to be smaller. In the present embodiment, the number of the divided stators 10 is 18, β is 20 degrees, and α is 19 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 back yoke covering portion 12b is configured not to cover the joining end surfaces 11d and 11d of the back yoke portion 11b.
In this embodiment, the thickness of the insulating resin coating 12 is 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 in which the split stator core 11 is fastened in an annular shape has the joint end faces 11d of the split stator cores 11 adjacent in the stator circumferential direction D2 in contact with each other over the entire surface. Since the inner peripheral end 11g of the joining end face 11d is contacted in advance and arranged in an annular shape, the contact pressure of the contact end face 11e on the inner end side of the joining end face is higher than the contact pressure of the contact face 11f on the outer end side of the joining end face. Become big.

  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 split stator 10 around which the coil 14 is wound is brought into contact with the inner peripheral end 11g of the joining end surface 11d, and the outer peripheral side is positioned in a non-contact manner in an annular shape. Place it.
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 has the outer peripheral surface of the back yoke portion 11b of the divided stator core 11 at the stator center O in the process of reducing the diameter. Press inward. Then, as shown in FIGS. 7A and 7B, the outer peripheral side of the non-contact joining end surface 11d comes into contact, and the entire joining end surfaces 11d and 11d are brought into close contact with each other.
In this state, the adjacent divided stators 10 and the outer ring 20 for shrinkage are integrally fixed to form a stator 30.

  In the manufacturing process of the stator 30, when the divided stator core 11 is arranged in an annular shape, the inner peripheral ends 11g of the joining end surfaces 11d of the adjacent back yoke portions 11b are arranged in contact with each other in the manufacturing process of the stator 30. The split stator core 11 can be positioned by the inner peripheral end 11g. Further, when the outer peripheral surface of the split stator core 11 is pressed inward by the outer ring 20 for shrink shrinkage, stress concentrates on the inner peripheral end 11g, and the adjacent split stator cores 11 press each other in the stator circumferential direction D2. Further, it is possible to suppress the movement of each divided stator core 11 in the direction of the stator center O, and to minimize the displacement of the divided stator core 11. Therefore, variation in the inner peripheral surface of the divided stator core 11 can be eliminated and the inner diameter roundness of the stator 30 can be increased. Therefore, the gap between each divided stator core 11 and the rotor 40 can be made constant, and the motor The characteristics can be improved.

  In addition, the joining end faces 11d and 11d are not formed into a complicated shape, and the angle formed by the joining end faces 11d and 11d is merely smaller than the angle obtained by dividing 360 degrees by the number of the divided stators 10, so that the existing divisions It is easy to change the design from the stator core, and it is not necessary to create a complicated mold, so that the manufacturing cost can be reduced, and the assemblability is good when the stator 30 is formed.

  Further, in the stator 30 having the above-described configuration, the magnetic flux B generated by the coil 14 of each divided stator 10 passes through both sides on the back yoke portion 11b side, and from both joint end surfaces 11d and 11d to both sides in the stator circumferential direction D2. Flows to the joining end faces 11d and 11d of the back yoke portion 11b adjacent to the back yoke portion 11b. At that time, the contact pressure of the contact surface 11e on the inner peripheral side of the joint end surface 11d, which is a position corresponding to the path of the magnetic flux B and has a high magnetic flux density, is made higher than the contact pressure of the contact surface 11f on the outer peripheral side. Since the magnetic flux B that has passed through the inner peripheral contact surface 11e of the joining end surface 11d is dispersed on the outer peripheral contact surface 11f, non-uniformity of the magnetic flux density can be eliminated and saturation of the magnetic flux B can be prevented. Can do. Therefore, reduction of electric energy, that is, iron loss can be reduced, and motor characteristics can be improved.

Furthermore, if 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 costs can be reduced.
In addition, since the insulating resin coating layer formed on the winding portion of the coil 14 of the divided stator core 11 is formed of a molded product, the insulating resin coatings 12-1 and 12-2 are attached to the divided stator core 11 at necessary locations. The insulating resin layer can be provided simply by fitting.

  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 which shows the angle which the joining end surface of a back yoke part 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 a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Split stator 11 Split stator core 11a Teeth part 11b Back yoke part 11d Joining end surface 11e Inner peripheral side contact surface 11f Outer peripheral side contact surface 12 Insulating resin coating 14 Coil 20 Outer ring 30 for shrink shrinkage Stator 50 Motor D1 Stator diameter Direction D2 Stator circumferential direction D3 Stator axial direction B Coil flux

Claims (5)

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
In a state where the divided stator cores are arranged in an annular shape, the inner peripheral ends of the joint end faces of adjacent split stators are in contact with each other and separated from the outer peripheral side, and the angle α formed by these joint end faces is 360 degrees. The divided stator core is characterized in that it is set smaller than the angle β divided by the number of divided stators constituting the.   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 formed by arranging the split stator core according to claim 3 in an annular shape,
The joint end surfaces of the back yoke portions of the adjacent divided stator cores are in contact with each other over the entire surface, and the contact pressure of the inner peripheral contact surface is larger than the contact pressure of the outer peripheral contact surface. It is a manufacturing method of the stator according to claim 4,
The split stator core is arranged in an annular shape, the inner peripheral end of the joint end surface of the split stator core adjacent in the circumferential direction is contacted, and the outer peripheral side is positioned as non-contact,
An outer ring for shrinking is externally fitted on the outer peripheral surface of the back yoke portion arranged in an annular shape, and the outer ring is shrinked to shrink the diameter.
The stator manufacturing method, wherein the non-contact outer peripheral side is also brought into contact in the diameter reduction step, and the entire joining end face is pressed.

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