JP2004064924A - Core sheet, stator, and rotating electromotor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a core sheet which can improve motor performance. <P>SOLUTION: In a coupling section between the tooth 12a of an inner core 12 and an outer core 11, a wide part 12f which widens in circumferential direction more than the tooth 12a is made in the tooth 12a. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a core sheet, a stator using the core sheet, and a rotary electric motor using the stator.
[0002]
[Prior art]
2. Description of the Related Art Some rotating magnetic field type motors such as brushless motors are configured using a stator core (referred to as a stator in the publication) as disclosed in Japanese Patent No. 2875497.
[0003]
The stator core disclosed in the above publication is configured by laminating a plurality of core sheets obtained by press-punching a magnetic metal plate material. The stator core (core sheet) has a ring-shaped outer core (outer core sheet portion) and a teeth portion (iron core portion) that extends linearly in the radial direction with substantially the same width and winds a winding in the circumferential direction. An inner core is provided at a plurality of intervals and is connected in a ring shape in a circumferential direction at an inner end portion, and an inner peripheral portion of the outer core is connected to an outer end portion of the teeth portion. That is, in the stator core as described in the above publication, the winding can be wound around the teeth of the inner core before the outer core and the inner core are joined, and in this case, the winding is wound from outside the teeth. Therefore, there is an advantage that the winding operation is easy and the space factor of the winding can be improved.
[0004]
[Problems to be solved by the invention]
By the way, in the above-mentioned publication, since the teeth portion of the inner core has a shape that extends linearly in the radial direction with substantially the same width, the members are not smoothly connected to each other at the joint portion between the tooth portion and the outer core. For this reason, the magnetic path is bent at a substantially right angle at this joint, so that the magnetic resistance is large. As a result, there has been a problem that the motor performance is reduced.
[0005]
The present invention has been made to solve the above problems, and an object of the present invention is to provide a core sheet capable of improving motor performance, a stator using the core sheet, and a rotary motor using the stator. To provide.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, an invention according to claim 1 is a core sheet for forming a stator core by laminating a plurality of sheets in an axial direction, wherein the core sheet has a ring shape and has a plurality of first couplings on an inner peripheral portion. An outer core having a portion, a teeth portion extending in the radial direction and arranged at a predetermined interval in the circumferential direction, and a radially inner end portion of the teeth portion for winding the coil and connecting the tooth portion in a circumferential direction to a ring shape. An inner core having a connecting portion and a second connecting portion provided at a radially outer end portion of the tooth portion and connecting to the first connecting portion, wherein at a connecting portion between the tooth portion of the inner core and the outer core, At least one of the teeth portion and the outer core is formed with a widened portion that is wider than the teeth portion in a circumferential direction.
[0007]
According to a second aspect of the present invention, in the core sheet according to the first aspect, in the joint portion between the teeth portion of the inner core and the outer core, the teeth portion is wider than the teeth portion in the circumferential direction. A part is formed.
[0008]
According to a third aspect of the present invention, in the core sheet according to the first or second aspect, when the first and second coupling portions are coupled to each other, a force is generated such that the teeth portion is pressed against the outer core. Is formed.
[0009]
According to a fourth aspect of the present invention, in the core sheet according to any one of the first to third aspects, the outer core and the inner core are formed by press punching the same part of a magnetic metal plate.
[0010]
According to a fifth aspect of the present invention, there is provided a stator core formed by laminating a plurality of the core sheets according to any one of the first to fourth aspects in an axial direction, and an insulator formed by resin molding and mounted on the stator core. And a winding wound with the insulator interposed between the teeth of the stator core.
[0011]
According to a sixth aspect of the present invention, in the stator according to the fifth aspect, the insulator has an in-slot covering portion that covers an inner peripheral surface of the slot between the teeth portions. And an outer-side covering portion extending circumferentially along the inner peripheral portion so as to insulate the inner core from the outer core and covering the widened portion.
[0012]
According to a seventh aspect of the present invention, there is provided a rotary electric motor including the stator according to the fifth or sixth aspect, and a rotor rotated by the stator.
(Action)
According to the first aspect of the present invention, at a joint portion between the teeth portion of the inner core and the outer core, at least one of the teeth portion and the outer core is formed with a widened portion that is wider than the teeth portion in the circumferential direction. You. That is, by providing the widened portion wider than the tooth portion on at least one of the tooth portion and the outer core, the bending of the magnetic path at the joint portion between the tooth portion of the inner core and the outer core is gently improved, and the magnetic resistance is reduced. . Therefore, the characteristics of a stator using such a core sheet are improved, and the performance of a rotary motor using the stator is improved.
[0013]
According to the second aspect of the present invention, in the joint portion between the teeth portion of the inner core and the outer core, the teeth portion is formed with a widened portion that is wider than the teeth portion in the circumferential direction. That is, since the widened portion wider than the tooth portion is provided in the tooth portion, the bending of the magnetic path at the joint between the tooth portion of the inner core and the outer core is gradually improved, and the magnetic resistance is reduced. Therefore, the characteristics of a stator using such a core sheet are improved, and the performance of a rotary motor using the stator is improved.
[0014]
According to the third aspect of the present invention, the first and second coupling portions are formed such that when they are coupled to each other, a force is generated to press the teeth portion against the outer core. Therefore, when the tooth portion and the outer core are pressed against each other, the magnetic resistance of the joint portion is further reduced.
[0015]
According to the fourth aspect of the invention, the outer core and the inner core are formed by press punching the same portion of the magnetic metal plate. For this reason, the difference in distortion between the outer core and the inner core is reduced, so that the axial deviation between the two cores when they are connected to each other can be suppressed to a small value.
[0016]
According to a fifth aspect of the present invention, a stator is formed by resin molding and mounted on a stator core formed by laminating a plurality of the core sheets according to any one of the first to fourth aspects in the axial direction. And a winding wound with the insulator interposed between the teeth of the stator core. That is, since the core sheet having the reduced magnetic resistance is used, the characteristics of the stator are improved, and the performance of the rotary electric motor using the stator is improved.
[0017]
According to the invention as set forth in claim 6, the insulator has an in-slot covering portion covering the inner peripheral surface of the slot between the teeth portions, and the in-slot covering portion is insulated from the inner peripheral portion of the outer core. In order to achieve this, an outer-side covering portion extends in the circumferential direction along the inner peripheral portion and also covers the widened portion. Therefore, since the outer-side covering portion is supported by the widened portion by covering the widened portion, a force that bends radially outward with respect to the outer-side covered portion at the time of winding the winding or the like. Cracking when acting can be prevented.
[0018]
According to a seventh aspect of the present invention, a rotary electric motor includes the stator according to the fifth or sixth aspect, and a rotor rotated by the stator. That is, the performance of the rotary motor is improved because the stator having excellent characteristics is used.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a sectional view of the brushless motor 1. A substantially annular stator 3 is inserted and fixed to the inner peripheral surface 2 a of the cylindrical motor housing 2. The stator 3 includes a stator core 4, an insulator 5, and a winding 6.
[0020]
As shown in FIG. 2, the stator core 4 is a laminated core formed by laminating a plurality of core sheets 10 obtained by press-punching a magnetic metal plate. The stator core 4 (core sheet 10) includes an outer core 11 and an inner core 12.
[0021]
The outer core 11 has a ring shape, and has twelve coupling concave portions 11b (first coupling portions) formed at equal intervals (30 ° intervals) in a circumferential direction in an inner peripheral portion 11a. Each of the coupling recesses 11b has a substantially trapezoidal shape in which the inner side in the radial direction is open and the sides facing in the circumferential direction are closer to each other toward the inner side in the radial direction. Each coupling recess 11b is formed to be slightly smaller than the width (peripheral width) of each tooth 12a described later.
[0022]
The concave portions 11c are also formed between the coupling concave portions 11b, and are formed when the inner core 12 is subjected to press punching. That is, in the present embodiment, the outer core 11 and the inner core 12 are formed by press-punching the same portion of the magnetic metal plate material so that the outer core 11 and the inner core 12 are separated from each other at the concave portion 11c. When the outer core 11 and the inner core 12 are connected, the inner core 12 is punched out of the outer core 11 such that the connecting protrusion 12e of the inner core 12 (teeth portion 12a) is connected to the original connecting recess 11b. The coupling protrusion 12e and the coupling concave portion 11b are coupled by rotating the coupling convex portion 12e by 15 ° from the position (where the concave portion 11c is formed). When the outer core 11 and the inner core 12 are formed by press-punching the same portion of the magnetic metal plate material as described above, the difference in distortion between the two cores 11 and 12 becomes small, and thus the two cores 11 and 12 when they are joined to each other are formed. Axial deviation can be kept small.
[0023]
The inner core 12 has twelve teeth portions 12a which extend linearly in the radial direction with substantially the same width and are arranged at equal intervals (30 ° intervals) in the circumferential direction for winding the winding 6, and each of the tooth portions 12a has The inner ends are connected in a ring shape in the circumferential direction by a connecting portion 12b, and a rotor accommodating hole 12c is formed in the inner peripheral portion. The connecting portion 12b for connecting the teeth portions 12a is provided with a thin portion 12d formed at the center thereof so as to be thinner than other portions. The thin portion 12d is provided to increase the magnetic resistance in order to reduce the leakage magnetic flux between the adjacent teeth portions 12a.
[0024]
As shown in FIGS. 2 and 3, a coupling convex portion 12e (second coupling portion) that is coupled (fitted) to the coupling concave portion 11b of the outer core 11 is formed at an outer end of each tooth portion 12a. ing. Each coupling projection 12e has a substantially trapezoidal shape in which the sides facing in the circumferential direction are closer to each other toward the inside in the radial direction so as to correspond to the coupling concave portion 11b. The coupling projection 12e and the coupling recess 11b are formed such that, when coupled to each other, a force is generated in a direction in which the teeth 12a are pulled radially outward (a direction in which the teeth 12a are pressed against the outer core 11).
[0025]
At the outer end of each tooth portion 12a, a widened portion 12f extending in both circumferential directions is formed radially inward of the coupling convex portion 12e. Each widened portion 12f contacts the inner peripheral portion 11a of the outer core 11, and enlarges the contact portion of the teeth portion 12a with the outer core 11. Also, each widened portion 12f is formed so as to gradually widen in the circumferential direction as it proceeds radially outward. By providing such a widened portion 12f, the connecting portion between each tooth portion 12a and the outer core 11 is connected as smoothly as possible. Therefore, as shown by an arrow A in FIG. Become gentle. That is, since the bending of the magnetic path of the coupling portion is gradually improved, the magnetic resistance can be reduced.
[0026]
Further, as described above, when the coupling convex portion 12e and the coupling concave portion 11b are coupled, a force is generated in a direction of pulling the tooth portion 12a outward in a radial direction (a direction in which the tooth portion 12a is pressed against the outer core 11). The portion presses against the inner peripheral portion 11 a of the outer core 11. Therefore, this also reduces the magnetic resistance at the joint between each tooth 12a and outer core 11. Further, in this case, a force is generated in a direction in which the teeth 12a are pulled radially outward by the connection between the connection protrusions 12e and the connection recesses 11b, but each widened portion 12f makes contact with the outer core 11 at each tooth 12a. Since the portion is enlarged, the abutting portion can sufficiently receive the pulling force. Therefore, the deformation of the rotor accommodation hole 12c provided in the inner peripheral portion of the inner core 12 can be suppressed to a small value, and the axial deviation of the accommodation hole 12c can be prevented. Incidentally, in the present embodiment, the width between the circumferential end portions of the widened portions 12f provided on each tooth portion 12a is larger than the width of the tooth portion 12a, and the central angle is 360 ° / 2n (n is the tooth portion). 12a), that is, within a predetermined range smaller than 15 °.
[0027]
The insulator 5 is formed by resin molding, is mounted on the stator core 4 (the inner core 12), and is insulated from the winding 6 wound around each of the teeth portions 12a. The insulator 5 is composed of two components that can be mounted from both ends in the axial direction, respectively, and an end surface coating portion (not shown) that insulates the axial end surface of each tooth portion 12a from each other, and between each tooth portion 12a, ie, a slot. A slot inner coating portion 5a for insulatingly coating the inner peripheral surface of 12g. Then, the in-slot covering portions 5a are inserted into the slots 12g of the stator core 4 (the inner core 12) from both ends in the axial direction, and the insulator 5 is mounted so as to sandwich the stator core 4 (the inner core 12) in the axial direction. Since the in-slot covering portion 5a has a minute gap with respect to the inner peripheral surface of the slot 12g, it is easy to insert the in-slot covering portion 5a into the slot 12g.
[0028]
The outer coating 5a extends in the circumferential direction along the inner peripheral portion 11a so as to cover the widened portion 12f of the teeth portion 12a and a part of the inner peripheral portion 11a of the outer core 11. A portion 5b is formed. The outer-side covering portion 5b is provided to insulate the winding 6 from the inner peripheral portion 11a of the outer core 11. The outer-side covering portion 5b is supported by the widened portion 12f of the teeth portion 12a. For this reason, the outer-side covering portion 5b has a shape extending long in the circumferential direction. However, even when a force is applied to the outer-side covering portion 5b such that the outer-side covering portion 5b bends radially outward when the winding 6 is wound. Since it is supported by the widened portion 12f of the teeth portion 12a, it is prevented from being broken.
[0029]
In the stator 3 having such a configuration, the outer core 11 and the inner core 12 are formed by laminating a plurality of core sheets 10 in the axial direction, and the insulator 5 is attached to the inner core 12 before the outer core 11 and the inner core 12 are combined. The inner core 12 and the outer core 11 are attached to each other, and the windings 6 are wound around the tooth portions 12a of the inner core 12, and then the inner core 12 and the outer core 11 are connected to each other to be completed. Inside the stator 3 thus formed (that is, inside the rotor accommodating hole 12c), the rotor 15 to which eight magnets 16 having different polarities in the circumferential direction are fixed on the outer peripheral surface thereof is rotatable. It is arranged. The rotor 15 is rotated by a rotating magnetic field generated in the stator 3 by supplying a drive current to the winding 6 of the stator 3.
[0030]
Next, the features of the above-described embodiment will be enumerated below.
(1) In the present embodiment, in the joint portion between the tooth portion 12a of the inner core 12 and the outer core 11, the tooth portion 12a is formed with a widened portion 12f which is wider than the tooth portion 12a in the circumferential direction. That is, by providing the widened portion 12f wider than the tooth portion 12a in the tooth portion 12a, the bending of the magnetic path of the joint portion between the tooth portion 12a of the inner core 12 and the outer core 11 is gently improved. Can be reduced. Therefore, the characteristics of the stator 3 using the core sheet 10 are improved, and the performance of the brushless motor 1 using the stator 3 can be improved. In particular, since each widened portion 12f is formed so as to gradually widen in the circumferential direction as it goes radially outward, these effects become even greater.
[0031]
(2) In the present embodiment, the coupling concave portion 11b of the outer core 11 and the coupling convex portion 12e of the tooth portion 12a of the inner core 12 are formed such that when they are coupled to each other, a force is generated to press the tooth portion 12a against the outer core 11 side. I have. Therefore, when the teeth portion 12a and the outer core 11 are brought into pressure contact with each other, the magnetic resistance of the joint portion can be further reduced.
[0032]
(3) In the present embodiment, the outer core 11 and the inner core 12 are formed by press-punching the same portion of a magnetic metal plate. For this reason, the difference in distortion between the outer core 11 and the inner core 12 is reduced, so that the axial deviation of the cores 11 and 12 when they are coupled to each other can be reduced. In addition, the material of the magnetic metal plate material for forming the cores 11 and 12 is good.
[0033]
(4) In the present embodiment, the insulator 5 has the in-slot covering portion 5a that covers the inner peripheral surface of the slot 12g between the teeth portions 12a. An outer-side covering portion 5b extends in the circumferential direction along the inner peripheral portion 11a to cover the widened portion 12f so as to insulate the portion from the portion 11a. Therefore, the outer-side covering portion 5b covers the widened portion 12f and is supported by the widened portion 12f. Therefore, the outer-side covered portion 5b is radially outward with respect to the outer-side covered portion 5b when the winding 6 is wound. Cracking when a bending force acts can be prevented. If the widened portion 12f is not provided, the frequency of breaking the outer-side covering portion 5b of the insulator 5 increases, and the present embodiment is excellent in this respect.
[0034]
Note that the embodiment of the present invention may be modified as follows.
In the above embodiment, the widened portion 12f is provided on the tooth portion 12a of the inner core 12, but may be provided on the outer core 11 side. Moreover, you may provide in both. Further, the shape of the widened portion 12f is not limited to this, and may be appropriately changed.
[0035]
In the above-described embodiment, the coupling protrusions 12e are provided on the teeth 12a of the inner core 12, and the coupling recesses 11b are provided on the outer core 11, but these may be provided in reverse. In addition, the shapes of the coupling protrusion 12e and the coupling recess 11b are not limited thereto, and may be appropriately changed. In addition, although the teeth 12a are formed so as to generate a force for pressing the outer core 11 by the connection of the connection protrusions 12e and the connection recesses 11b, a shape that does not particularly generate this force may be used.
[0036]
In the above-described embodiment, the outer core 11 and the inner core 12 are formed by press-punching the same portion of the magnetic metal plate material. Both cores 11 and 12 may be formed of different portions of the magnetic metal plate, or both cores 11 and 12 may be formed of another magnetic metal plate.
[0037]
In the above embodiment, the teeth portions 12a are arranged at equal intervals on the inner core 12, but the arrangement may not be equal intervals and may be changed as appropriate. Further, the number of the teeth portions 12a may be other than 12.
[0038]
In the above embodiment, the present invention is applied to the stator 3 of the brushless motor 1, but may be applied to a rotary electric motor other than the brushless motor, for example, the stator of an induction motor.
[0039]
The technical ideas that can be grasped from the above embodiments are described below.
(A) The core sheet according to any one of claims 1 to 3,
The first coupling portion provided in the outer core is a coupling concave portion whose inner side in the radial direction is open,
The core sheet according to claim 1, wherein the second connecting portion provided in the teeth portion of the inner core is a convex portion fitted into the connecting concave portion.
[0040]
(B) In the core sheet described in (a) above,
The coupling concave portion and the coupling convex portion have a substantially trapezoidal shape such that sides facing in the circumferential direction are closer to each other toward the inside in the radial direction, and when they are coupled to each other, the teeth portion is pressed against the outer core side. A core sheet formed to generate a force.
[0041]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to provide a core sheet capable of improving motor performance, a stator using the core sheet, and a rotary electric motor using the stator.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a rotary electric motor according to an embodiment.
FIG. 2 is a perspective view of a stator core.
FIG. 3 is an enlarged sectional view of a main part of a stator.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 3 ... Stator, 4 ... Stator core, 5 ... Insulator, 5a ... Slot inner coating part, 5b ... Outer side coating part, 6 ... Winding, 10 ... Core sheet, 11 ... Outer core, 11a ... Inner peripheral part, 11b ... First A coupling concave portion as a coupling portion, 12 inner core, 12a teeth portion, 12b coupling portion, 12e coupling convex portion as a second coupling portion, 12f widening portion, 12g slot, 15 rotor.

Claims (7)

A core sheet for forming a stator core by laminating a plurality of sheets in the axial direction,
An outer core having a ring shape and having a plurality of first coupling portions on an inner peripheral portion;
A tooth portion extending in the radial direction and arranged at a predetermined interval in the circumferential direction for winding a winding, a connecting portion for connecting a radially inner end of the tooth portion in a circumferential direction in a ring shape, and the tooth portion; An inner core that is provided at a radially outer end of the inner core and has a second coupling portion coupled to the first coupling portion.
A core sheet in which a widened portion that is wider in a circumferential direction than the tooth portion is formed on at least one of the tooth portion and the outer core at a coupling portion between the tooth portion of the inner core and the outer core. . The core sheet according to claim 1,
A core sheet, wherein a widened portion that is wider in a circumferential direction than the tooth portion is formed in the tooth portion at a joint portion between the tooth portion of the inner core and the outer core. The core sheet according to claim 1 or 2,
The core sheet, wherein the first and second coupling portions are formed such that when they are coupled to each other, a force is generated to press the teeth portion against the outer core. The core sheet according to any one of claims 1 to 3, wherein the outer core and the inner core are formed by pressing and punching the same part of a magnetic metal plate material. A stator core formed by laminating a plurality of core sheets according to any one of claims 1 to 4 in an axial direction,
An insulator formed by resin molding and attached to the stator core,
Winding wound in a state where the insulator is interposed in the teeth portion of the stator core,
A stator characterized by having a special feature. The stator according to claim 5,
The insulator has an in-slot covering portion covering the inner peripheral surface of the slot between the teeth portions, and the in-slot covering portion is provided on the inner peripheral portion to insulate the inner peripheral portion of the outer core from the inner peripheral portion. A stator having an outer-side covering portion extending in a circumferential direction along the outer periphery and also covering the widened portion. A stator according to claim 5 or 6,
A rotor rotated by the stator;
A rotary electric motor comprising:

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