JP2011188730A - Ring coil motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve various constitutional problems such as displacement of an electromagnetic steel plate, by efficiently transmitting a torque generated at a rotor to a load. <P>SOLUTION: A ring coil motor includes: a stator unit 300 having a stator core 304 and a ring coil 310; a rotor unit 400 having a rotor core unit 401 with a rotor magnetic tooth 403 and a rotor magnetic pole 402, and a first and second rotor core holders 307, 308 mutually fixed tightly to sandwich end of the rotor core unit 401 from both sides in the radial direction, and disposed on the same axis as the rotor core unit 401. The rotor magnetic teeth 403 are formed of the electromagnetic steel plate, and the torque generated at the rotor unit 400 is transmitted to a rotational shaft through the rotor core holders 307, 308. An end surface 415 along the rotational axis of the rotor magnetic teeth 403 is made flat and continuous, and is brought into contact with the first rotor core holder 307 in the end surface 415. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a ring coil motor having an improved transmission mechanism for transmitting torque from a rotor to a load.

Small motors applied to technical fields such as robots and industrial machines are required to facilitate coil winding and mounting, improve coil mounting density, and improve efficiency and torque characteristics.
6 and 7 show examples of the ring coil motor described in Patent Document 1, FIG. 6 shows an outer rotor type, and FIG. 7 shows an inner rotor type step motor.

In FIG. 6, 1 is a fixed shaft, 2 and 3 are bearings, 4 is a rotor case, 5 is a rotor yoke, 6 and 7 are stator yokes, 8 and 9 are ring coils, and 10 is a magnet plate.
In FIG. 7, 11 is a rotating shaft, 12 and 13 are bearings, 15 is a rotor yoke, 16 and 17 are stator yokes, 18 and 19 are ring coils, and 20 is a magnet plate.
Teeth are formed on the opposing surfaces of the rotor yokes 5 and 15 and the stator yokes 6, 7, 16, and 17, and permanent magnets are disposed between these teeth.

In the motor, as the rotor rotates, the magnetic flux interlinked with the ring-shaped coils 8, 9, 18 and 19 is changed by the action of the built-in permanent magnet, that is, no load induced voltage is generated in these coils. It is configured as follows. Therefore, a torque is generated in the motor by passing an alternating current through the coil.
In these ring coil motors, it is not necessary to arrange a coil in the slot as in a normal motor, the manufacture of the ring coil is easy, and high torque can be generated by the interaction between the stator and rotor It has the characteristics.

In general, when it is desired to reduce the size of the entire apparatus by arranging the motor in a narrow space, it is desirable to use a flat motor having a short axial length.
However, the motor shown in FIGS. 6 and 7 assumes a motor in which the radial gap, that is, the gap formed by the opposed surfaces of the stator and the rotor is cylindrical. Since this type of motor tends to be long in the axial direction, it is difficult to form the motor flat. In particular, when three-phase coils are arranged in the axial direction, flattening of the motor is more difficult to realize.

Furthermore, the inner rotor type motor shown in FIG. 7 has a structure in which the side portions and the outer peripheral portion of the ring-shaped coils 18 and 19 are surrounded by the stator yokes 16 and 17, so the structure of the coils 18 and 19 is simple. Nevertheless, when the coils 18 and 19 are incorporated in the stator yokes 16 and 17, there is a problem that a complicated assembly work is required.
In order to facilitate this assembling work, a method is conceivable in which the stator yokes 16 and 17 are divided into two portions near the central portion in the axial direction and coupled after sandwiching the coil. In this case, the magnetic path in the stator core is limited. Since it is divided, the magnetic resistance increases, resulting in a decrease in torque.
On the other hand, according to the outer rotor type motor shown in FIG. 6, since the ring-shaped coils 8 and 9 are arranged around the stator yokes 6 and 7, assembly work is easy. There are not necessarily many product fields to which can be applied.

Further, in this type of motor, a mechanism for transmitting torque generated in the rotor to a load via the rotating shaft is required to satisfy the following magnetic requirements and restrictions.
That is, it is necessary to link the magnetic flux generated from the magnetic poles of the rotor to the ring coil as much as possible, and to increase the magnetic resistance of the magnetic circuit where it is not desired to link the magnetic flux. In other words, it is desired to reduce the necessary magnetic resistance of the magnetic circuit, that is, to reduce the gap between the rotor magnetic teeth and the stator magnetic teeth as much as possible (reduce the clearance tolerance).
In addition, it is also necessary to prevent the generation of circulating current and eddy current by minimizing the use area of the conductor.
Furthermore, as a structural requirement, it has the strength to withstand the transmission of torque, and as described above, in order to reduce the clearance tolerance between the rotor magnetic teeth and the stator magnetic teeth, the parts are manufactured with high precision, and the dimensional tolerances of the parts are also increased. It is required to provide a mechanism capable of absorbing, to reduce the number of parts, and the like.

In view of the above points, the present applicant has already applied for an electromagnetic unit for a ring coil motor as shown in FIGS. 8 and 9 are exploded perspective views of the electromagnetic unit, and FIG. 10 is a perspective view of the rotor magnetic teeth and rotor magnetic poles in FIGS.
Hereinafter, the structure of this electromagnetic unit will be described in detail.

In FIG. 8, reference numeral 100A denotes a stator unit, which is a substantially cylindrical first stator core 104 that is short in the axial direction, a second substantially similar cylindrical stator core 105, and these stator cores 104 and 105 are magnetically coupled. And a yoke 151. The inner diameter of the first stator core 104 is longer than the outer diameter of the second stator core 105, and these stator cores 104, 105 are arranged concentrically. Further, stator magnetic teeth 106 and 107 are formed on the opposing surfaces of the stator cores 104 and 105 over the entire circumference thereof. The outer stator magnetic teeth 106 and the inner stator magnetic teeth 107 are formed so as to be shifted by, for example, 5 ° in the circumferential direction.
The stator cores 104 and 105 are formed of dust cores, and their central axes coincide with the rotation axis of the rotor unit 200E. Although the ring-shaped coil is accommodated in the gap between the stator cores 104 and 105, the ring-shaped coil is not shown in FIGS. 8 and 9 for convenience.

A rotor core unit 239 is arranged above the ring coil in the gap between the stator cores 104 and 105. The rotor core unit 239 is configured such that a large number of rotor magnetic teeth 240 are arranged radially along the circumferential direction, and rotor magnetic poles 241 (see FIG. 10) are arranged between adjacent rotor magnetic teeth 240. The rotor magnetic pole 241 is formed in a substantially fan shape when viewed from the axial direction as described above.
The rotor magnetic teeth 240 are produced by cutting a laminated steel plate obtained by previously bonding a plurality of electromagnetic steel plates, that is, an adhesive steel plate by wire cutting, and the adjacent rotor magnetic teeth 240 are, for example, 5 ° in the circumferential direction. They are arranged at intervals (angles). By using an adhesive steel plate as the rotor magnetic teeth 240, the number of parts is reduced and assembly is facilitated. Moreover, it is possible to manufacture the rotor magnetic tooth 240 of a precise shape by cutting out from the bonded steel sheet by wire cutting.

9 and 10, reference numeral 242 denotes a magnetic steel sheet, which is shown as a reference component for the rotor magnetic teeth 240. A notch 243 is formed at substantially the center of the outer peripheral portion of the rotor magnetic tooth 240 (electromagnetic steel plate 242). When the rotor core unit 239 is formed, the notch 243 continuous in the circumferential direction is shown in FIGS. A ring-shaped fastener 247 shown in FIG. Further, as shown in detail in FIG. 10, notches 245 and 246 are also formed at one axial end portion of the rotor magnetic tooth 240 (the electromagnetic steel plate 242). In these notches 245 and 246, as shown in FIGS. 8 and 9, other ring-shaped fasteners 248 and 249 are attached, respectively.
The fasteners 247, 248, and 249 are made of a non-magnetic material such as plastic or a non-conductive material, and the rotor magnetic teeth 240 and the rotor magnetic pole 241 are integrally fastened using the fasteners 247, 248, and 249. As a result, the rotor magnetic pole 241 can be prevented from falling off and moving, and the rotor core unit 239 that is stable and strong against external force (for example, torque or magnetic attraction force) can be formed.

Furthermore, a slit 244 is formed at the other axial end of the rotor magnetic tooth 240 (electromagnetic steel plate 242) (the end opposite to the notches 245 and 246). The slit 244 applies a spring force in the radial direction to the rotor magnetic teeth 240, so even if there is a large dimensional tolerance, the tolerance can be absorbed by a small stress.
The spring action of the rotor magnetic teeth 240 by the slits 244 contributes to the absorption of this tolerance even if there are some tolerances due to slightly different diameters and roundness of the rotor core holders 250 and 252 and the rotor core unit 239 described later. Thereby, the uneven load between the rotor magnetic teeth 240 due to dimensional tolerance can be suppressed as much as possible. Further, the assembly dimension on the inner diameter side of the rotor magnetic teeth 240 can be made to follow the roundness of the outer side of the cylindrical portion of the rotor core holder 250.

In FIG. 9, reference numeral 250 denotes a first rotor core holder, and a cylindrical portion 251 is formed on the lower surface thereof. In FIG. 8, reference numeral 253 denotes a bolt hole formed in the rotor core holder 250. Further, reference numeral 252 denotes a ring-shaped second rotor core holder, and the first and second rotor core holders 250 and 252 are bolted in a state where the rotor core unit 239 is sandwiched in the axial direction together with the first rotor core holder 250. And the rotor core unit 239 is integrally connected and fixed. Here, the first and second rotor core holders 250 and 252 are made of a nonmagnetic material having high strength and excellent processing accuracy and high toughness such as aluminum, and a magnetic short circuit between the rotor magnetic teeth 240. Is preventing.
Although not shown, the first rotor core holder 250 is connected to a rotating shaft by a bolt or the like.
The rotor unit 200E is configured by the rotor core unit 239, the fasteners 247, 248, 249, and the first and second rotor core holders 250, 252 described above.

On the outer peripheral surface of the cylindrical portion 251 of the first rotor core holder 250 and the inner peripheral surface of the second rotor core holder 252, chamfered portions 254 and 255 having a 72-face cut are formed, respectively.
If the outer peripheral surface of the cylindrical portion 251 and the inner peripheral surface of the rotor core holder 252 remain curved, a crescent-shaped gap is formed between the outer peripheral surface and the rotor magnetic teeth 240 that contact the inner peripheral surface. End up. In this case, when the second rotor core holder 252 is pulled up to the first rotor core holder 250 side by a bolt, a shearing stress in the radial direction is generated on the bonding surface of the rotor magnetic teeth 240 made of a bonded steel plate, and mechanical Is unstable. Accordingly, the chamfered portions 254 and 255 are formed on the outer peripheral surface of the cylindrical portion 251 and the inner peripheral surface of the rotor core holder 252 to solve the above problem.
The tapered portion 256 of the rotor magnetic tooth 240 shown in FIG. 10 is in contact with the chamfered portion 255 on the inner peripheral surface of the second rotor core holder 252.

Japanese Patent Laid-Open No. 10-23732 (paragraphs [0006] to [0009], FIG. 1, FIG. 8, etc.)

According to the electromagnetic units shown in FIGS. 8 to 10, as described above, it is possible to solve various problems required for the mechanism for transmitting the torque generated in the rotor to the load. There is a new problem that the electromagnetic steel plate 242 constituting the plate is easily displaced with the rotation of the rotor.
SUMMARY OF THE INVENTION An object of the present invention is to provide a ring coil motor that can transmit torque generated in a rotor to a load with high efficiency and that can solve various structural problems such as displacement of electromagnetic steel sheets. .

In order to solve the above-mentioned problems, the invention according to claim 1 is a ring-shaped stator core having a plurality of stator magnetic teeth regularly arranged along the circumferential direction, and is arranged close to the same axis as the stator core. A stator unit having a ring-shaped coil,
A ring-shaped rotor core unit having a rotor magnetic tooth and a rotor magnetic pole opposed to the stator magnetic teeth via a gap, and fastened and fixed to each other so as to sandwich the end of the rotor core unit from both sides in the radial direction; and A rotor unit having first and second rotor core holders arranged coaxially with the rotor core unit,
In the ring coil motor in which the rotor magnetic teeth are made of an electromagnetic steel plate, and the torque generated in the rotor unit is transmitted to the rotating shaft via the first and second rotor core holders.
An end surface of the rotor magnetic tooth along the rotation axis is a flat and continuous end surface, and the end surface is brought into contact with the first rotor core holder.

  The invention according to claim 2 is characterized in that, in the ring coil motor according to claim 1, a slit for absorbing a dimensional tolerance is formed in the rotor magnetic tooth.

  The invention according to claim 3 is the ring coil motor according to claim 2, wherein the center point of the contact load between the rotor magnetic teeth and the first rotor core holder is the second rotor core holder and the rotor magnetic teeth. It is on the extension of the straight line which connects the contact point and the edge part of the said slit, Comprising: It exists in the tooth tip side along the said rotating shaft rather than the root of the said rotor magnetic tooth, It is characterized by the above-mentioned.

  The invention according to claim 4 is the ring coil motor according to any one of claims 1 to 3, wherein an unmagnetized magnetic material is used as the rotor magnetic pole, and the stator unit and the rotor unit are combined. A direct current is passed through the ring coil with one end surface in the radial direction of the rotor magnetic teeth facing the stator magnetic teeth to magnetize the rotor magnetic poles.

  According to a fifth aspect of the present invention, in the ring coil motor magnetized with the rotor magnetic pole according to the fourth aspect, the rotor core unit is rotated by one pitch, and the direct current in the direction opposite to the direct current is applied to the ring coil. The rotor magnetic poles are again magnetized through the flow.

According to the present invention, the torque generated in the rotor can be transmitted with high efficiency to the rotary shaft and, in turn, the load via the rotor magnetic teeth and the rotor core holder. In addition, various structural problems such as preventing the rotor magnetic teeth made of electromagnetic steel plates from being displaced to prevent interference with the stator core can be solved.
Furthermore, there is an advantage that the assembling work is facilitated by devising the magnetizing method of the rotor magnetic poles.

It is a disassembled perspective view of the principal part in 1st Embodiment of this invention. It is expansion explanatory drawing around the rotor magnetic tooth in 1st Example. It is expansion explanatory drawing around the rotor magnetic tooth in 2nd Example. It is expansion explanatory drawing around the rotor magnetic tooth in 3rd Example. It is an expanded sectional view of the principal part in 2nd Embodiment of this invention. It is sectional drawing of the principal part which shows a prior art. It is sectional drawing of the principal part which shows a prior art. It is a disassembled perspective view of the principal part of the electromagnetic unit which concerns on a prior application invention. It is a disassembled perspective view of the principal part of the electromagnetic unit which concerns on a prior application invention. FIG. 10 is a perspective view of the rotor magnetic teeth and rotor magnetic poles in FIGS. 8 and 9.

Embodiments of the present invention will be described below with reference to the drawings.
First, FIG. 1 is a perspective view in which a main part of a ring coil motor according to this embodiment is partially cut away.
1, 300 is a stator unit formed in substantially the same manner as in FIGS. 8 and 9, and includes a stator core 304 having a substantially U-shaped cross-section along the radial direction, and a circumferential direction on the inner facing surface thereof. A large number of stator magnetic teeth 306 and 307 are formed at a pitch of 10 ° over the entire circumference. The outer stator magnetic teeth 306 and the inner stator magnetic teeth 307 are shifted by, for example, 5 ° in the circumferential direction.
A ring-shaped coil 310 is housed inside the stator core 304, and the central axis thereof coincides with the rotational axis of the rotor unit 400 described later.

  Here, the role of the stator core 304 is to form a magnetic circuit interlinked with the ring coil 310 by a combination with rotor magnetic teeth and rotor magnetic poles (permanent magnets). As is well known, in the ring coil motor, the interlinkage magnetic circuit efficiently converts the electric energy supplied to the ring coil 310 into magnetic energy, and then converts the magnetic energy into kinetic energy to drive the load. ing. The higher the magnetic permeability of the stator core 304, the more energy can be converted and the higher torque can be generated.

The material of the stator core 304 is preferably low conductivity. An alternating current is passed through the ring coil 310 to convert electrical energy into magnetic energy. For this reason, naturally, the stator core 304 will be exposed to an alternating magnetic field, and an eddy current is easy to generate | occur | produce. When the eddy current is generated, the energy is changed to heat loss, not only the energy conversion efficiency is lowered, but also the temperature of surrounding parts is raised to generate thermal stress. When the thermal stress is generated in this way, there is a possibility that the problem of strength of the parts may be developed. Therefore, it is preferable to use a material having a low conductivity that hardly generates eddy current for the stator core 304.
Further, the stator core 304 according to the present embodiment has a three-dimensional structure as shown in FIG. 1, and it is difficult to manufacture the stator core 304 using a so-called laminated steel plate. For this reason, the material of the stator core 304 is required to be easily processed so as to realize a three-dimensional structure.
From this point of view, it is most desirable to use a dust core as the material of the stator core 304, which has high magnetic permeability and low electrical conductivity and is suitable for processing a three-dimensional structure.

Further, in FIG. 1, reference numeral 401 denotes a rotor core unit, which is disposed close to the ring coil 310 in the gap inside the stator core 304.
The rotor core unit 401 is configured by arranging a large number of rotor magnetic teeth 403 radially along the circumferential direction and disposing a rotor magnetic pole 402 between adjacent rotor magnetic teeth 403. The rotor magnetic teeth 403 are made of laminated steel plates (electromagnetic steel plates) formed by cutting a bonded steel plate by wire cutting, have a substantially flat plate shape, and are arranged at intervals (angles) of, for example, 5 ° in the circumferential direction. The rotor magnetic pole 402 is formed in a substantially fan shape when viewed from the axial direction.
Here, the reason why the rotor magnetic teeth 403 are formed of a magnetic steel sheet is to prevent the generation of eddy current as described above.

Reference numeral 407 denotes a first rotor core holder, which includes a cylindrical portion 404, and a donut-shaped outer flange plate 405 and an inner flange plate 406 that are orthogonal to the cylindrical portion 404. Reference numeral 408 denotes a doughnut-shaped second rotor core holder, and the second rotor core holder 408 is fastened and fixed coaxially with the outer flange plate 405 by bolts 409, and together with the first rotor core holder 407, the rotor core unit. 401 is held. A ring-shaped gap 410 is formed between the first rotor core holder 407 (outer flange plate 405) and the second rotor core holder 408.
Each of the first and second rotor core holders 407 and 408 is made of high strength such as aluminum, high processing accuracy, high toughness, and a non-magnetic material. Here, the nonmagnetic material is used because when the rotor magnetic teeth 403 are magnetically short-circuited, the magnetic flux linked to the ring-shaped coil 310 is reduced and the generated torque is reduced. It is for insulation.
Although not shown, the inner flange plate 406 of the first rotor core holder 407 is connected to a rotating shaft for driving a load.

Next, FIG. 2 is an enlarged explanatory view around the rotor magnetic teeth 403 in FIG. 1, and shows a first embodiment of the present invention.
As shown in the figure, the second rotor core holder 408 is fastened to the outer flange plate 405 of the first rotor core holder 407 with bolts 409, and is loaded in the direction of arrow a (rotational axis direction) toward the outer flange plate 405. Is added.
A tapered portion 411 is formed on the root outer diameter side of the rotor magnetic teeth 403 in the same manner as in FIG. 10, and is in contact with a 72-surface chamfered portion 412 formed on the inner peripheral surface of the second rotor core holder 408. Yes. A slit 413 is formed in the vicinity of the tapered portion 411 of the rotor magnetic tooth 403.
Reference numeral 414 denotes a fastener made of a nonmagnetic material such as plastic or a nonconductive material for integrally fastening a large number of rotor magnetic teeth 403 and rotor magnetic poles 402.

As described above, the load in the direction of arrow a is applied to the second rotor core holder 408, and the chamfered portion 412 contacts the tapered portion 411 to apply a pressing force in the radial direction, whereby the rotor magnetic teeth 403 and the outer flange plate 405 are applied. A large frictional force is generated between the second rotor core holder 408 and the rotor magnetic teeth 403 are firmly fixed. One end surface 415 along the rotation axis of the rotor magnetic teeth 403 is formed as a continuous flat surface, and the rotor magnetic teeth 403 and the outer flange plate 405 are in close surface contact with each other at the end surface 415. .
Therefore, the torque generated in the rotor magnetic teeth 403 when the motor is rotated is efficiently transmitted to the first rotor core holder 407 by the above frictional force, and is transmitted to the load with high efficiency via a rotating shaft (not shown). Is.

In this embodiment, the rotor magnetic teeth 403 and the second rotor core holder 408 are in contact with each other by the tapered portion 411 and the chamfered portion 412 as described above. For this reason, even if the diameters of the two are slightly different and there is a dimensional tolerance, the dimensional tolerance can be absorbed and the rotor magnetic teeth 403 and the second rotor core holder 408 can be reliably brought into contact with each other. Further, the slit 413 formed in the rotor magnetic tooth 403 functions as a spring in the same manner as the slit 244 in FIG. 10, so even if there is a certain dimensional tolerance in the rotor magnetic tooth 403, the slit 413 can reduce this tolerance. For example, a sufficient pressing force and frictional force are generated for the rotor magnetic teeth 403 that are absorbed and formed to be smaller than a predetermined size.
It should be noted that there is a tolerance in the substantially fan-shaped space where the rotor magnetic pole 402 itself and the rotor magnetic pole 402 are arranged. For this reason, it is possible to make the inner diameter side thickness of the rotor magnetic pole 402 thinner and the outer diameter side thickness thicker than the predetermined gap so that the rotor magnetic pole 402 does not move too much inward in the radial direction. desirable.

  Here, in the rotor magnetic tooth 240 according to the invention of the prior application shown in FIG. 10, the end surfaces 240a and 240b are not arranged in a straight line as shown in FIG. 10, but are discontinuous and bent by the opening of the slit 244. Is arranged in. Accordingly, the rotor magnetic teeth 240 are in contact with the inner surface of the first rotor core holder 250 only at the end surface 240a, and the contact surface pressure is mainly applied to the corners 240c and 240d of the end surface. For this reason, the frictional force at the contact surface between the rotor magnetic teeth 240 and the first rotor core holder 250 is weak, and the rotor magnetic teeth 240 are rotated in the above rotation direction when the rotor is rotated or when the rotor core holders 250 and 252 are fastened with bolts. There is a problem that it is easily displaced (rotates).

If the rotor magnetic teeth 240 are displaced from their original positions, they may interfere with the stator core 304. If the gap length between the stator core 304 and the stator core 304 is increased in order to reduce the risk, the magnetic resistance increases and consequently The output torque will decrease.
Therefore, in this embodiment, as shown in FIG. 2, the rotor magnetic teeth 403 and the outer flange plate 405 of the first rotor core holder 407 are brought into close surface contact with each other at a flat and continuous end surface 415, so that the rotor magnetic teeth 403 Deviation of the rotor magnetic teeth 403 is prevented by increasing the frictional force between the first rotor core holder 407 and the first rotor core holder 407.

Next, a second embodiment of the present invention will be described.
As described above, the rotor magnetic teeth 403 and the first rotor core holder 407 are brought into surface contact with the continuous and flat end surface 415 to prevent the rotor magnetic teeth 403 from shifting, as shown in FIG. Since the slit 413 is formed inside the rotor magnetic teeth 403, it is difficult to process, and there is a manufacturing problem.
Therefore, in the second embodiment, as shown in FIG. 3, the structure in which the rotor magnetic teeth 403A and the outer flange plate 405 of the first rotor core holder 407 are in close surface contact with each other at the flat and continuous end surface 415 is left as it is. A substantially L-shaped slit 413A that opens at the outer periphery of the rotor magnetic teeth 403A is formed.
Thereby, the advantage that the process of slit 413A becomes easy is acquired.
On the other hand, when the stress calculation is performed on the second embodiment of FIG. 3, it has been found that there is a problem in the distribution of the contact load on the cylindrical portion 404 by the rotor magnetic teeth 403A. Specifically, since the contact load with respect to the cylindrical portion 404 is distributed around the root of the rotor magnetic tooth 403A, the rotor magnetic tooth 403A will not be displaced even when the bolt 409 is tightened, but the magnetic force in the direction of the arrow b. There is a problem that it is easy to shift when the is added.

Therefore, in the third embodiment of the present invention, as shown in FIG. 4, the rotor magnetic teeth 403B and the outer flange plate 405 of the first rotor core holder 407 are brought into close surface contact with each other at a flat and continuous end surface 415. The structure is left as it is, and the position d closer to the tip of the rotor magnetic tooth 403B is the center of the contact load with respect to the cylindrical portion 404 as compared with the second embodiment of FIG.
Specifically, by changing the cross-sectional shape of the chamfered portion 412B of the second rotor core holder 408 or the shape of the tapered portion 411B, the contact point c between the rotor magnetic teeth 403B and the second rotor core holder 408 is changed to the rotor magnetic teeth. 403B is moved to the tooth tip side, and the slit 413B is formed in a substantially L shape opposite to the slit 413A in FIG. 3, and the slit end 413b is also arranged on the tooth tip side of the rotor magnetic tooth 403B, The point d of the contact load center with respect to the cylindrical portion 404 exists on the extension of the line connecting the contact point c and the slit end 413b. That is, the point d at the center of the contact load moves from the root of the rotor magnetic tooth 403B to the tooth tip side along the rotation axis as compared with FIG.
Accordingly, even when a magnetic force is applied in the direction of the arrow b in FIG. 4, the magnetic teeth 403 </ b> B are not easily displaced, and the risk of interference with the stator core 304 can be reduced.

Next, a second embodiment of the present invention will be described.
In the first embodiment (first to third examples) described above, in the rotor core unit 401 composed of the rotor magnetic teeth 403 and the rotor magnetic poles 402, the rotor units adjacent in the circumferential direction have opposite polarities. Thus, the rotor magnetic pole 402 is magnetized.
Therefore, when a large number of rotor core units 401 are arranged in the circumferential direction between the first and second rotor core holders 407 and 408 and fastened by the fasteners 414, the adjacent rotor core units 401 repel each other by magnetic force, and the rotor In some cases, the assembly operation of the unit 400 may be hindered.
The second embodiment of the present invention is for solving the above problems.

FIG. 5 is an enlarged cross-sectional view of the main part in the second embodiment, and a partial enlargement of the rotor core unit 401 and the stator unit 300 when the ring coil motor shown in FIG. 1 is cut along a plane orthogonal to the rotation axis. It is sectional drawing. In FIG. 5, the same components as those in FIGS. 1 to 4 are denoted by the same reference numerals.
In this embodiment, the rotor core unit 401 is formed by using an unmagnetized magnetic material as the rotor magnetic pole 402, and the rotor core unit 401 is aligned in the circumferential direction and fastened by the fastener 414. For this reason, in assembling the rotor unit 400, the adjacent rotor core units 401 do not repel each other due to the magnetic force, and there is no possibility of hindering the work of arranging a large number of rotor core units 401 in the circumferential direction.

Here, the magnetizing operation of the rotor magnetic pole 402 is performed after the assembly of the stator unit 300 and the rotor unit 400, and without using a dedicated magnetizing device (magnetizing yoke), the stator magnetic teeth 306 and 307 and the ring. The rotor magnetic pole 402 is magnetized using a constituent member of a ring coil motor such as the shape coil 310.
That is, in FIG. 5, the rotor unit 400 (rotor core unit 401) is rotated manually, for example, so that one end surface (inner side or outer end surface) of each rotor magnetic tooth 403 is opposed to the stator magnetic tooth 306 or 307. It shows the state that was made to. When a direct current is passed through the ring coil 310 in this state, a magnetic field is generated. For example, the outer stator magnetic teeth 306 → the rotor magnetic teeth 403 → the rotor magnetic poles 402 and 402 → the adjacent rotor magnetic teeth 403 → the inner stator magnetic teeth. Magnetic flux flows along the path 307.
The rotor magnetic poles 402 are magnetized by flowing the magnetic flux in this way, and the adjacent rotor core units 401 have opposite polarities in the circumferential direction, which is the same as when assembled after the rotor magnetic poles 402 are pre-magnetized. A ring coil motor can be obtained.

In addition, when magnetizing by flowing a magnetic flux through the above-described path, the magnetic flux flows in a portion where energy loss is small, so there is a possibility that the portions indicated by reference numerals 402a and 402b in FIG. It is called a finely magnetized part).
Accordingly, in order to sufficiently magnetize these finely magnetized portions 402a and 402b, the rotor core unit 401 is rotated by one pitch so that the magnetic flux flows in the direction opposite to the above-described path, that is, the inner stator. A direct current is passed through the ring coil 310 so that the magnetic flux flows through the path of the magnetic teeth 307 → the rotor magnetic teeth 403 → the rotor magnetic poles 402 and 402 → the adjacent rotor magnetic teeth 403 → the outer stator magnetic teeth 306.
Thereby, since the magnetic flux also flows in the finely magnetized portions 402a and 402b, the rotor magnetic pole 402 can be magnetized on the average.

Also in the second embodiment, the structure of the rotor magnetic teeth 403, 403A, and 403B and the second rotor core holder 408 shown in FIGS. 2 to 4 can be applied.
According to this embodiment, in addition to the effects of the first embodiment, there is an advantage that the assembly work of the ring coil motor becomes easy.

In each of the embodiments and examples described above, the material of the first and second rotor core holders is not limited to aluminum. Needless to say, the arrangement pitch of the stator magnetic teeth and the rotor magnetic teeth is not particularly limited.
Furthermore, although the taper part of the rotor magnetic teeth is shown only on the outer side (opposite the rotating shaft), it may be formed on the inner side or on both the inner and outer sides. A plurality of rotor magnetic tooth slits may be provided.
In addition, it goes without saying that the structure of the ring coil motor of the present invention is not limited to that shown in FIG.

300: Stator unit 304: Stator core 306, 307: Stator magnetic tooth 310: Ring coil 400: Rotor unit 401: Rotor core unit 402: Rotor magnetic pole 402a, 402b: Finely magnetized portions 403, 403A, 403B: Rotor magnetic tooth 404: Cylindrical portion 405: outer flange plate 406: inner flange plate 407: first rotor core holder 408: second rotor core holder 409: bolt 410: gap 411: taper portion 412 and 412B: chamfered portion 413, 413A, 413B: slit 413b : Slit end 414: Fastener 415: End face

Claims (5)

A ring-shaped stator core having a plurality of stator magnetic teeth regularly arranged along the circumferential direction, and a stator unit having a ring-shaped coil arranged coaxially with the stator core;
A ring-shaped rotor core unit having a rotor magnetic tooth and a rotor magnetic pole opposed to the stator magnetic teeth via a gap, and fastened and fixed to each other so as to sandwich the end of the rotor core unit from both sides in the radial direction; and A rotor unit having first and second rotor core holders arranged coaxially with the rotor core unit;
With
In the ring coil motor in which the rotor magnetic teeth are made of an electromagnetic steel plate, and the torque generated in the rotor unit is transmitted to the rotating shaft via the first and second rotor core holders.
A ring coil motor characterized in that an end surface of the rotor magnetic tooth along the rotation axis is a flat and continuous end surface, and the end surface is brought into contact with the first rotor core holder. In the ring coil motor according to claim 1,
A ring coil motor, wherein a slit for absorbing a dimensional tolerance is formed in the rotor magnetic tooth. In the ring coil motor according to claim 2,
The center point of the contact load between the rotor magnetic teeth and the first rotor core holder is
On the extension of a straight line connecting the contact point between the second rotor core holder and the rotor magnetic teeth and the end of the slit, and the tooth tip along the rotation axis rather than the root of the rotor magnetic teeth Ring coil motor characterized by being on the side. In the ring coil motor according to any one of claims 1 to 3,
An unmagnetized magnetic material is used as the rotor magnetic pole, and the stator unit and the rotor unit are combined so that one end surface in the radial direction of the rotor magnetic teeth is opposed to the stator magnetic teeth and a direct current is applied to the ring coil. A ring coil motor characterized by passing a current and magnetizing the rotor magnetic pole. In the ring coil motor in which the rotor magnetic pole is magnetized according to claim 4,
A ring coil motor, wherein the rotor core unit is rotated by one pitch, and a direct current in a direction opposite to the direct current is passed through the ring coil to magnetize the rotor magnetic pole again.

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