JPH10234147A - Dynamo-electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dynamo-electric machine with a decrease in pulsating torque and number of parts for simple constitution and size reduction, and high efficiency. SOLUTION: This dynamo-electric machine involves a stator 2 having a stator winding 5 and a stator iron core 4, and rotor 3 rotating through an appropriate clearance from the stator 2, whereas the stator core 4 is formed by weld-building components, in the peripheral direction, which are integral in the axial direction, divided by a stator iron core tooth part 42 in the peripheral direction, and whose cross section is of -letter shape having a yoke part 41 and a bridge part 43 which are integral with a tooth part 42.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rotating electric machine,
Its small size, light weight and high efficiency.

[0002]

2. Description of the Related Art A motor for an electric vehicle such as an electric vehicle is desired to be small, lightweight and highly efficient. For this reason, a brushless motor using a permanent magnet type first and a reluctance type second is most suitable. In particular, in the field of small machines, a brushless motor that can employ a concentrated winding method for the stator winding of the stator core teeth is effective.

As a conventional example, Japanese Patent Application Laid-Open No. 7-29852
There is an electric motor described in Japanese Patent Publication No. According to this disclosure, by winding the stator winding intensively on the stator core teeth divided in the circumferential direction, the coil end portion of the stator winding is shortened, and the space factor of the coil is reduced. Can be improved.

[0004]

According to the above cited example, the size of the electric motor can be reduced. However, since the inner and outer peripheral portions of the stator core are welded to fix the stator core teeth, iron loss increases. In addition, since the configuration is such that the components are stacked in the axial direction, the number of components is large, and the configuration is complicated. Further, since the stator iron core teeth are not separated in the circumferential direction, they have a large harmonic magnetic flux, which causes pulsation torque and increases iron loss. There are still problems.

An object of the present invention is to provide a small, lightweight, and high-efficiency rotary electric machine that overcomes the above-mentioned problems of the prior art.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a stator having a stator winding, a stator having a stator core on which the stator winding is wound, and rotating through a suitable gap with the stator. In a rotating electric machine having a rotor, the stator core is achieved by assembling a stator magnetic pole composed of unit parts that are axially integrated and divided by stator core teeth in the circumferential direction.

The stator magnetic pole is integrally formed in the axial direction, is divided by a stator core tooth portion, and is wound around the tooth portion with the unit component having a yoke portion and a bridge portion integrated with the tooth portion. Stator windings.

[0008] In the case of external winding, the unit component has a substantially "E" shaped cross section in the axial direction after shaping, and a stator winding is wound around a core tooth located at the center thereof. The unit part is formed from one magnetic plate, and two members having a substantially U-shaped cross section obtained by dividing the core teeth are formed back-to-back with the core teeth. Thereafter, the yoke portions of the unit components are joined to assemble the stator.

In the case of the assembled coil, the unit component has a substantially "c" -shaped cross section in the axial direction after shaping, the opening side being the bridge section, the opposite side being the yoke section, and both sides therebetween being the tooth section. Become. The stator core is assembled by joining the outer peripheral sides of the teeth.

The magnetic material for shaping the unit parts may be a single plate, a laminated plate or a molded product made of magnetic powder or the like as long as it is integrated in the axial direction. Other features of the present invention will be apparent through the description of the embodiments.

According to the configuration of the present invention, it is possible to provide a small, lightweight and highly efficient rotating electric machine as described below. That is, the stator cores are not laminated in the axial direction, but are integrally formed in the axial direction. Therefore, the number of parts is small, and the configuration is simplified. Since there is no weld on the inner peripheral side of the stator core, iron loss can be significantly reduced.

The unit parts can be molded in the same shape from, for example, one steel plate, and thus are suitable for mass production. Since the stator is assembled after winding the stator winding around the unit parts,
Not only can the winding be simplified, but also the wire area ratio can be increased and the stator core slit width can be reduced. Further, a magnetic slit portion for suppressing the magnetic flux in the circumferential direction is formed between the stator core teeth that are back-to-back, so that the harmonic magnetic flux circulating on the inner periphery of the iron core teeth can be suppressed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a plurality of embodiments of the present invention will be described in detail with reference to the drawings. The same components are denoted by the same reference numerals throughout the drawings.

[Embodiment 1] FIG. 1 is a structural view of a rotary electric machine according to Embodiment 1, and FIG. 2 is a sectional view thereof. This embodiment is a permanent magnet rotating electric machine, which is an embodiment of a concentrated winding rotating electric machine in which a stator winding is intensively wound around a stator core tooth portion.

The rotating electric machine 1 includes a stator 2 and a rotor 3, and the stator 2 includes a stator core 4 and a stator winding 5. The stator core 4 includes a stator core tooth portion 42, a stator core yoke 41 and a stator core bridge portion 43 forming a passage of the magnetic flux, and the stator winding 5 is wound around the stator core tooth portion 42. ing. Each of the stator windings 5 has a concentrated winding stator structure that does not share a magnetic path in the air gap surface.
Since the length of the end coil portion can be made shorter than that of a stator having a distributed winding structure used in a general large-sized machine, it is advantageous in reducing the size of the rotating electric machine. Here, a configuration is shown in which there is no frame on the outer periphery of the stator core 4, but a frame may be used if necessary.

The rotor 3 has a configuration in which permanent magnets 6 adjacent to each other at substantially equal pitches are arranged with different polarities. The rotor 3 has a rotor yoke 7 through which the magnetic flux of the permanent magnet passes, and a shaft 9. , And is rotatably held by the end bracket 10 via the bearing 11. Rotor shaft 9
A magnetic pole position detector for detecting the position of the permanent magnet 6 and a position detector (not shown here) are provided above.

Furthermore, U1 +, U
1-, U2 +, U2-, V-phase V1 +, V1-, V2 +, V2-, W
W1 +, W1-, W2 +, and W2- are connected to the phases, respectively.
Here, the number of the suffice is the number of the stator winding, +,-
Indicates the winding direction of the stator winding.

In this embodiment, as shown in FIG. 1, the stator core 4 is divided into the same number as the stator windings 5 in the circumferential direction. In other words, a stator core component 40 having the same number as that of the stator windings 5 and having a cross section of “D” is formed in a circumferential direction. The components 40 are each integrally formed in the axial direction. The component 40 is formed by winding the winding 5 around the iron core teeth 42 to form a stator magnetic pole.

FIG. 3 shows a process of manufacturing the stator core components. One plate member of (a) is punched out from one magnetic iron plate to form a stator core yoke portion 41, a stator core tooth portion 42, and a stator core bridge portion 43, and bent as shown in (b). 401 is formed. further,
As shown in (c), the core teeth of the two single-sided members 401 are back-to-back, and the two are joined together 85 to form the stator core component 40 having a D-shaped cross section. From the viewpoint of the component parts 40, the one-side member 401 has a shape divided at the center of the iron core teeth 42.

Each of the components 41, 42, 43 of the component 40 is made of a single magnetic plate in the axial direction, and is literally integrated. Note that, even when the component 40 is formed from a material obtained by laminating a plurality of magnetic plates as shown in FIG. 3, the components are integrally formed in the axial direction.

According to this configuration, when the stator core 4 is assembled by the configuration of the stator core component 40 described above, the welded portion 12 becomes the end face 13 of the core yoke portion 41. For this reason, a short circuit is not formed in the stator core 4 by welding the inner peripheral portion of the core 4 unlike the related art.
Therefore, the occurrence of iron loss can be minimized. Since the innermost iron plate does not need to be welded, there is no swelling unlike a conventional laminated iron core, and the assembling accuracy can be improved.

Further, since a magnetic gap (slit) 85 is formed in the adjacent part of the one side member 401 of the component part 40, the amount of magnetic flux passing therethrough can be reduced. Thereby, for example, the slits 8 of the stator iron teeth 42 of W2-
When 5 matches the gap between the N and S poles of the permanent magnet of the rotor 3, the magnetic resistance of the loop that returns from the N pole to the S pole through the surface of the stator core teeth 42 increases, and the stator windings increase. The harmonic magnetic flux that does not interlink with the wire 5 is reduced, and the iron loss can be reduced as compared with the conventional structure without the slit 85.

Further, the stator winding 5 can be wound around the stator core component 40 before assembling the stator 2 in the state of FIG. Winding becomes possible. After winding, each component 4
Since the stator cores 0 are joined together by the welds 12, the spacing between the stator core slits 8 between the stator core teeth 42 can be reduced, and pulsation torque such as cogging torque is reduced.

Further, a directional magnetic steel plate is used as the magnetic iron plate, and a direction having good magnetic characteristics is selected in a direction in which a magnetic flux passes, in this case, in an inner circumferential direction of the iron core teeth 42 (radial direction of the rotating electric machine). , Iron loss can be reduced.

Further, as shown in FIG. 3, a structure in which the stator core teeth 42 are shortened in the axial direction with respect to the yoke 41 and the bridge 43 can be easily formed. This makes it possible to provide a flat rotating electric machine having a short axial length for an increase in output or efficiency for the same shaft length and a constant physique.

[Embodiment 2] FIG. 4 shows a second embodiment of the present invention. FIG. 1A shows the structure of a rotating electric machine, and FIG. The difference from the first embodiment in FIG. 1 is that an auxiliary groove for reducing cogging torque is provided in the stator core.

As shown in an enlarged view in FIG. 4B, the stator core teeth 4 are provided on the inner peripheral surface of the bridge 43 of the stator core 4.
Auxiliary grooves 44 having substantially the same magnetic permeance as the slit portions 8 between the two are arranged at equal intervals.

As shown in FIG. 4 (c), when forming the component parts 40 of the stator core 4 which are integrally formed in the axial direction and divided in the circumferential direction by the stator teeth 42, the bridge part 43 of the one-side member 401 is formed. The auxiliary groove 44 is shaped. The position and the number of the auxiliary grooves 44 are not limited to the present embodiment, and may be arbitrarily provided according to the law of cogging torque reduction.

Incidentally, the cogging torque of the permanent magnet rotating electric machine 1 is generated in a cycle of the least common multiple of the number of poles of the permanent magnet and the number of teeth of the stator core per rotation. The value decreases as the number of cycles increases. Therefore, as in the present embodiment, the auxiliary groove 44 is provided for each tooth 42.
By providing, the pulsating number 60 (the least common multiple of 10 and 12) of the cogging torque when there is no auxiliary groove,
The number of pulsations of the cogging torque can be increased to 180 (the least common multiple of 10 and 36), and the cogging torque can be reduced.

[Embodiment 3] FIG. 5 shows another embodiment of the present invention. FIG. 1A shows the structure of a rotating electric machine, and FIG. 1B shows an enlarged view of a main part thereof. The first and second embodiments are mainly examples of a permanent magnet brushless motor, but the present embodiment is an example of application to a permanent magnet step motor.

As shown in FIG. 3A, the permanent magnet rotor 3
Is a configuration having 32 poles here. On the other hand, the bridge portion 43 of the stator core 4 is configured to be slightly smaller than the magnetic pole pitch of the permanent magnet 6. In addition, bridge part 4
3 is provided with an auxiliary groove 44 of the stator core, the pitch of which is slightly larger than the magnetic pole pitch of the permanent magnet 6.

The stator core 4 is integrally formed in the axial direction by the same manufacturing method as in the first and second embodiments, and the tooth portions 42 are formed in the circumferential direction.
Is assembled from the component parts 40 divided by. Auxiliary groove 4
0 can be shaped in the same manner as in the second embodiment.

In the second embodiment, the auxiliary groove 44 acts to reduce the cogging torque, but in the present embodiment, acts to increase the number of stator magnetic poles, thereby contributing to an increase in the torque of the step motor. The numbers of the stator core bridge portions 43 and the auxiliary grooves 44 attached to one stator magnetic pole (the component 40) are not limited to the present embodiment, and the number of permanent magnet poles is also arbitrary.

[Embodiment 4] FIG. 6 shows another embodiment of the present invention. FIG. 1A shows a structure of a rotating electric machine, which is almost the same as FIG. FIG. 3B is a development view of a steel plate of a component constituting the stator core, and is a view corresponding to FIG. 3A. (C) is a sectional view of the component part obtained by shaping (b).

This embodiment is different from the first to third embodiments described above in that the components 4 are formed from one magnetic steel sheet without interposing one side member.
0 '. As shown, a slit 83 is provided in the stator core bridge 43 in a direction perpendicular to the axial direction, a slit 82 is provided in the stator core teeth 42, and a slit 81 is provided in the stator core yoke 41.

A slit 83 provided in the stator core bridge 43 and a slit 82 provided in the stator core teeth 42
Has the effect of cutting the path of the eddy current flowing in the axial direction to reduce the eddy current loss. In (b), the solid line shown in the axial direction indicates the bending point, and the component 40 'of (c) is formed by sequentially bending inward. Adjacent components 40 ′ fix the yoke 41 side of the iron core teeth 42 with the welded portion 12.

When the slit portion 81 provided in the stator core yoke portion 41 is formed in the shape shown in FIG.
The assembled stator 2 has a shape slightly larger than the state shown in FIG. As a result, the circumferential width of the slit portion 8 between the bridge portions 43 of the stator core 4 is increased, so that the stator winding 5 is wound around the core tooth portion 42 from the slit portion 8 by a winding jig. Enough space can be secured. After the winding of the stator winding 5 is completed, the slit 81 of the yoke portion 41 is crushed by applying a force from the outer periphery of the stator using a jig or the like, and the stator core teeth 42 and the stator winding Move line 5 in the circumferential direction,
The number of slits 8 of the bridge 43 is reduced, and the size of the stator 2 is reduced by one to shape the state shown in FIG.

As a result, it is possible to improve the space factor of the stator winding when winding the stator winding after assembling the stator core.

[Embodiment 5] FIG. 7 shows another embodiment of the present invention. (A) is a structure of a rotating electric machine, (b) is a development view of a steel plate as a component constituting a stator core, (c).
FIG. 3B is a cross-sectional view of the core tooth portion in FIG.

The components 40 constituting the stator core 4 are as follows:
One sheet steel shown in (b) is bent at a solid line portion to shape the one-side member 401, and is formed adjacent to each other at the tooth portions 42 of the two members 401. 6, a slit 83 is provided in the iron core bridge portion 43 at right angles to the axial direction.

In the present embodiment, the stator core teeth 4
2 is provided with a rib 45 for securing strength and a rib 46 for fixing. The stator winding 5 is wound externally around the component 40 thus shaped, and the fixing ribs 46 are aligned with the stator core yoke 41 and fixed.

According to the above configuration, a strong assembly structure of the stator core can be realized. Further, similarly to the other embodiments, there are effects such as a reduction in cogging torque and an improvement in the space factor of the stator winding. Further, when it is necessary to more firmly support the stator core, the stator core teeth can be held by a support member (not shown) using the space in the axial direction.

[Embodiment 6] FIG. 8 shows another embodiment of the present invention. (A) shows a stator structure before final shaping, and (b) shows a stator structure after final shaping.

4A, the yoke 41, the tooth 4
2. A stator core component 40 having a bridge section 43 and having a "deformed" cross section is formed by separately forming an annular yoke 4
7 is fixed by welding so as to form a slit portion 84. The component 40 is formed from an iron plate as in the other embodiments.

The stator winding 5 is wound around the stator core teeth 42 to form a stator magnetic pole. According to the present embodiment, the shape of the yoke portion 41 is deformed into the shape of “large” to form the slit portion 84, whereby the circumferential width of the slit portion 8 of the stator core is reduced after assembly. The spacing is sufficient for wire work, facilitating high-speed winding work.

After the completion of the winding, pressure is applied to the stator core 4 from the outer periphery to deform the stator core 4 until the slit portion 84 disappears. As a result, as shown in FIG.
The number of slits 8 is reduced, and the stator 2 is completed. Although the slit portion 84 is provided between the stator core and the annular yoke, there are also modifications such as providing the slit portion at the stator core teeth.

According to the present embodiment, in the case of the illustrated shape, the ratio of the windings to make the area between the magnetic poles can be increased from 50% in (a) to 75% in (b). In addition, since the circumferential width of the slit portion 8 is smaller than in the related art, the cogging torque can be reduced.

The first to seventh embodiments of the present invention have been described above. In the above description, an example in which the components that become the magnetic poles of the stator core are shaped from a single steel plate has been described.However, a molding material such as a plurality of laminated plates or a magnetic powder material is used, or partially bent or inserted. It is also possible to use a plurality of sheets.

Although the concentrated winding rotary electric machine has been described in particular as a permanent magnet rotary electric machine having a permanent magnet rotor structure, the same effect can be exerted when applied to a reluctance rotor. Furthermore, not only concentrated winding but also distributed winding may be used. Alternatively, the present invention is not limited to the electric motor, and may be a generator, and may be applied to a rotating electric machine using an external rotation type, an internal rotation type rotor, or a claw pole type rotor.

[0050]

According to the present invention, the stator core of the rotating electric machine is integrated in the axial direction, so that the conventional axially laminated core is unnecessary, and the stator is divided by the stator core teeth in the circumferential direction. Since the unit stator magnetic poles made of the same member are assembled, it is possible to easily realize a structure capable of improving the linear factor and reducing the iron loss, thereby providing a small, lightweight, and high-efficiency rotating electric machine. Is now possible.

[Brief description of the drawings]

FIG. 1 is a structural diagram of a rotating electric machine according to a first embodiment of the present invention.

FIG. 2 is a sectional view of the rotating electric machine of FIG. 1;

FIG. 3 is a production view of a component serving as a unit magnetic pole of a stator core in the rotary electric machine of FIG. 1;

FIG. 4 is a structural diagram of a rotating electric machine according to a second embodiment of the present invention.

FIG. 5 is a structural view of a rotary electric machine according to Embodiment 3 of the present invention.

FIG. 6 is a structural diagram of a rotating electric machine according to Embodiment 4 of the present invention.

FIG. 7 is a structural view of a rotary electric machine according to Embodiment 5 of the present invention.

FIG. 8 is a structural diagram of a rotary electric machine according to Embodiment 6 of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotating electric machine, 2 ... Stator, 3 ... Rotor, 4 ... Stator core, 40 ... Stator core component (stator magnetic pole), 401
... One-sided member, 41 ... stator core yoke, 42 ... stator core teeth, 43 ... stator core bridge, 44 ... auxiliary groove, 45 ... strength securing rib, 46 ... fixing rib, 47 ...
Annular yoke, 5: stator winding, 6: permanent magnet, 8: stator core slit portion, 81: slit, 82: slit,
83 ... slit, 84 ... slit, 85 ... slit, 9
... shaft, 10 ... end bracket, 12 ... weld,
13 ... Junction.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yutaka Matsunobu 7-1-1, Omikacho, Hitachi City, Ibaraki Prefecture Inside the Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Toshiyuki Yasushima 7-1, Omikamachi, Hitachi City, Ibaraki Prefecture No. 1 Hitachi, Ltd., Hitachi Research Laboratory (72) Inventor Ryoichi Naganuma 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Inside Hitachi, Ltd. Hitachi Research Laboratory (72) Inventor Kazuo Onishi, Kanda, Chiyoda-ku, Tokyo 7, Mitoshiro-cho, Japan Servo Co., Ltd. (72) Inventor Toshimi Abkawa 7, Kanda-Midshiro-cho, Chiyoda-ku, Tokyo Japan Servo Co., Ltd.

Claims (10)

[Claims] 1. A rotating electric machine having a stator winding, a stator having a stator core around which the stator winding is wound, and a rotor rotating through an appropriate gap with the stator. A rotating electric machine comprising a stator core integrally formed in an axial direction and a stator magnetic pole divided in a circumferential direction by teeth of a stator core. 2. A rotating electric machine having a stator winding, a stator having a stator core around which the stator winding is wound, and a rotor rotating through an appropriate gap with the stator. The stator core is formed by assembling in a circumferential direction a unit component having a yoke portion and a bridge portion which are integrally formed in the axial direction and divided in the circumferential direction by the stator core teeth and are integrally formed with the teeth. Characteristic rotating electric machine. 3. The rotating electric machine according to claim 2, wherein the stator core has a joint between the yoke portions of adjacent unit parts. 4. The rotating electric machine according to claim 1, wherein the stator core teeth divided in the circumferential direction are formed of one magnetic plate. 5. The rotating electric machine according to claim 4, wherein the one magnetic plate constituting the component has improved magnetic properties in the inner circumferential direction of the stator core teeth compared with the other directions. . 6. The rotating electric machine according to claim 1, wherein the stator winding is intensively wound around the stator core teeth. 7. The stator core tooth portion according to claim 1, wherein an axial length of the stator core teeth is shorter than an axial length of the stator core yoke or the stator core bridge. A rotating electric machine characterized by the above-mentioned. 8. The rotating electric machine according to claim 1, wherein an auxiliary groove is provided on a gap side of the stator core. 9. The rotating electric machine according to claim 1, wherein a rib for securing strength is provided in a part of the stator core. 10. The rotating electric machine according to claim 1, wherein a slit portion that can be shortened in a circumferential direction is provided in a yoke portion of the stator core.