JP5433828B2 - Rotating machine - Google Patents

Description

  The present invention relates to a low iron loss and high torque rotating machine and a method for magnetizing the permanent magnet.

  As a conventional rotating machine, a rotor in which N-pole and S-pole permanent magnets are alternately arranged is installed in parallel to the outer peripheral surface of the rotating shaft, and a stator in which a coil is wound around the outer periphery of the rotor via a gap. A plurality of rotating machines were used. For example, Japanese Patent Laid-Open No. 2008-61312 (Cited Document 1) discloses a motor in which an inner peripheral portion of an iron core around which a coil is wound is opposed to an outer peripheral surface of a rotor fixed to a shaft.

  Recently, an axial gap motor in which a stator and a rotor are arranged to face each other along a rotation axis has been developed. Japanese Patent Laid-Open No. 2007-252199 (Cited Document 2) discloses a first and second coil arrays facing each other, and a magnet array that is provided between the first and second coil arrays and includes at least one magnet. And the first and second coil arrays are disclosed as electric motors arranged at positions shifted from each other by an odd multiple of π / 2 in electrical angle. However, each coil of this electric motor does not have a magnetic material and a yoke, and is not sufficient as a torque to be obtained.

  Japanese Patent Laying-Open No. 2006-353078 (Cited Document 3) is an axial gap type rotating electrical machine in which a rotor and a stator are arranged to face each other in the rotor rotation axis direction, and electromagnetic waves are placed on the side of the rotor opposite to the stator. An axial gap type rotating electrical machine is disclosed, in which an auxiliary yoke made of a spirally laminated steel plate is provided, and the auxiliary yoke is housed in the case so that it cannot be displaced in the rotor rotation axis direction. However, this auxiliary yoke is for solving the problem of an increase in the burden on the rotor and the bearing due to the magnetic flux passing through the rotor surface and the surface vibration of the rotor, and does not improve the torque of the rotating electrical machine.

JP 2008-61312 A JP 2007-252199 A JP 2006-353078

  An object of the present invention is to provide a high torque rotating machine with low iron loss.

  As a result of diligent research in view of the above problems, the present inventors, in an axial gap type rotating machine, integrally form a tooth portion and a yoke portion around which a coil is wound on both sides of a rotor having a permanent magnet by a wound iron core. It was discovered that providing a fixed stator can provide a rotating machine with low iron loss and high torque, and the present invention has been conceived.

  That is, the present invention has the following features.

(1) A rotating shaft, a rotor connected perpendicularly to the rotating shaft and having a plurality of permanent magnets, and stators provided on both sides of the rotor via gaps, the stator being a yoke And a plurality of teeth portions around which coils are wound, and the teeth portions and the yoke portions are integrally formed of a wound iron core. Rotating machine.
(2) In the rotating machine described in the above (1), the teeth portion is provided at a tooth winding portion around which a coil is wound and a tip of the teeth winding portion, and has a diameter larger than that of the tooth winding portion. A rotating machine comprising: a tooth tip having a tooth.
(3) In the rotating machine described in (1) and (2) above, when the coil is a three-phase coil, the stators on both sides are (2n−1) π / 6 (n = 1, 2, 3...) Or a range in the vicinity of the rotating machine.
(4) In the rotating machine according to any one of (1) to (3), the plurality of permanent magnets are arranged such that N poles and S poles are alternately arranged at equal intervals in the circumferential direction of the rotor. A rotating machine characterized by that.

  According to the present invention, a rotor having a plurality of permanent magnets is connected perpendicularly to a rotating shaft, and a stator in which a tooth part and a yoke part for winding a coil are integrally formed by a wound iron core is provided on both sides of the rotor. As a result, a rotating machine with low iron loss and high torque can be obtained.

[1] rotating machine
(1-1) Configuration of Rotating Machine The configuration of the rotating machine 1 will be described below with reference to FIGS. The rotating machine 1 includes a rotor 10 that is connected to a rotating shaft 11 perpendicular to an outer peripheral surface and includes four permanent magnets 12, and a stator 20 that is provided on both sides of the rotor 10 via a gap. The permanent magnet 12 has N poles and S poles alternately arranged at equal intervals in the circumferential direction of the rotor 10. The stator 20 has a ring-shaped yoke portion 21 and six teeth portions 22 provided on the inner side surface of the yoke portion 21 and around which a coil 23 is wound. The stator 20 is housed in a bracket 24, and a bearing 14 is provided between the bracket 24 and the rotating shaft 11.

(1-2) Rotor As shown in FIG. 2, the rotor 10 includes four permanent magnets 12 in which N poles and S poles are alternately arranged at equal intervals in the circumferential direction, and a disk 13 containing the permanent magnets 12. It is a four pole rotor consisting of As shown in FIG. 3, the disk 13 is used to prevent the permanent magnet 12 from jumping out around the four pocket portions 130 for storing the permanent magnet 12 and the pocket portion 130 on the surface side of the disk 13. It consists of two disc lids 13a and 13b provided with an edge 131, a flange 132 provided on the outer side of the inner peripheral edge, and a notch 133 provided on the inner peripheral edge. As shown in FIG. 4, the disk lids 13 a and 13 b are attached to the rotary shaft 11 in a state of being overlapped so as to contain the four permanent magnets 12. At that time, by inserting the fixing member 15 into the notch 133 and a part of the rotor 10, it can be fixed to the rotating shaft 11 so that it does not move even if the rotor 10 rotates. As an attachment method, the flange 132 and the rotary shaft 11 may be fixed by screws or the like, or may be fixed by press-fitting, shrink fitting, adhesion or the like.

  The rotating shaft 11 is used as a rotating shaft of a rotating machine, and is not particularly limited as long as the disk 13 can be fixed, but special steel having sufficient strength is preferable.

  The permanent magnet 12 is not particularly limited as long as it is used in an AC rotating machine, but a neodymium magnet or the like is preferable. The permanent magnet 12 may be formed by sandwiching a magnetic material such as high-strength ferrite between two permanent magnets. Thereby, a larger magnetic field line is generated and a large torque is obtained.

  The disk 13 is preferably made of nonmagnetic stainless steel. Thereby, the influence of the disk 13 on the distribution of the lines of magnetic force generated by the permanent magnet 12 can be suppressed while the permanent magnet 12 is housed in a fixed state.

(1-3) Stator As shown in FIG. 5, the stator 20 includes a ring-shaped yoke 21 having a flat inner peripheral surface and six teeth portions 22 provided at equal intervals on the inner peripheral surface of the yoke 21. And have. A coil 23 is wound around each tooth portion 22. The coils 23 are appropriately insulated from each other and connected to a three-phase AC power source by lead wires (not shown), and an AC current flows so that adjacent teeth portions 22 have different polarities. be able to. In the present invention, the yoke 21 and the teeth portion 22 are integrally formed with the wound core, so that when the wound cores are connected to each other, iron loss does not occur, improving the efficiency of the rotating machine and generating local heat generation. Can be suppressed.

  The teeth portion 22 includes a teeth winding portion 221 that winds a coil, and a fan-shaped tooth tip portion 222 that is provided at the tip of the tooth winding portion 221 and has a larger diameter than the teeth winding portion 221. By making such an overhang shape, the surface area of the tooth portion 22 in contact with the permanent magnet 12 can be increased, so that the torque generated in the rotor 10 is increased. An insulating film (not shown) for insulating the coil 23 from the coil 23 is attached to the tooth winding part 221.

  The yoke 21 and the tooth portion 22 are preferably formed of a wound core formed by winding a core material rolled into a strip shape. Thereby, the iron loss by an eddy current can be reduced and the efficiency of a rotary machine can be improved. Examples of the iron core material include electromagnetic steel plates such as silicon steel plates, amorphous metal materials, nanocrystalline soft magnetic materials, permalloy, Fe-Si-Al alloys, and soft ferrites, with silicon steel plates being preferred. In conventional laminated iron cores, it was difficult to use an extremely thin iron plate in terms of punching and alignment, but a wound iron core can be used even with a much thinner iron plate than a laminated iron core. Since the iron loss is proportional to the square of the plate thickness and the 1.6th power of the frequency, the present invention can greatly reduce the iron loss of the stator, and in particular, can improve the efficiency of a motor driven at a high frequency.

[2] Operation of the rotating machine As described above, the rotor 10 is connected to the rotating shaft 11 perpendicularly to the outer peripheral surface, and the stator 20 is provided on both sides of the rotating shaft 11 via gaps. The magnetic field lines on both sides of the magnet 12 can be used to generate torque. Since the permanent magnet 12 is installed perpendicularly to the rotating shaft 11, sufficient torque characteristics can be obtained even if the thickness of the permanent magnet 12 is reduced. Therefore, since the thickness of the permanent magnet 12 can be reduced, iron loss caused by the permanent magnet can be suppressed. Thereby, the efficiency of the rotating machine 1 can be improved and the rotating machine can be downsized.

  Further, the rotating machine 1 of the present invention can cope with a wide range of rotation speeds of the rotor 10 and has an advantage of wide usage range. In particular, even when the number of rotations is reduced, the start-up is good. Specifically, when used in a pump, a sufficient flow rate can be obtained even when the number of rotations is 1000 or less. This is probably because the stator 20 is provided on both sides of the rotor 10 so that high torque can be obtained in the initial movement of the rotating machine.

  In the rotating machine 1 of the present invention, the rotor 10 is connected to the rotating shaft 11 perpendicular to the outer peripheral surface, and the stators 20 are provided on both sides thereof, so that the force applied between each stator 20 and the rotor 10 is affected. If there is a difference, a thrust load is applied to the entire rotating machine 1. In order to eliminate such thrust load, the dimension of the gap between each stator 20 and the rotor 10 is adjusted so that the thrust load is applied in the opposite direction to the thrust load applied to the entire rotating machine 1. Is preferred. Thereby, the thrust load can be offset. Thereby, the stable driving | operation of the rotary machine 1 is realizable and the lifetime of a bearing can also be extended.

Cogging of the motor can be suppressed by shifting the positions of the stators 20 on both sides and alternately applying torque from the stators 20 on both sides to the rotor 10. An example of the three-phase coil motor of FIG. 1 is shown in FIG. 4-pole rotor 10 shown in FIG. 6 (a), four permanent magnets 12a, 12b, 12c, 12d and on both sides of the stator 20a, the six teeth 22a of _{20b 1 ~22a 6, 22b 1 ~22b} 6 The stators 20a and 20b are provided with an electrical angle shifted by π / 2. The torque of the teeth 22a ₁ , 22a ₁ , and 22a ₁ of the stator 20a is the absolute value of the torque as shown in FIG. 6 (b) because the coil polarity changes when the torque becomes negative. It is shifted by 2π / 3. Therefore, the combined torque of the teeth portions 22a ₁ , 22a ₂ , 22a ₃ of the stator 20a is π / 3 period as shown in FIG. 6 (b). Therefore, by shifting the stator 20b so that the peak of the combined torque of the stator 20b is located at the valley of the combined torque of the stator 20a, that is, (2n-1) π / 6 (n = 1) in terms of electrical angle. , 2, 3...) By shifting, the cogging property of the torque applied to the rotor 10 can be suppressed. Further, since the peak position of the combined torque may be shifted due to the reactance torque generated between the rotor 10 and the stator 20, the stators 20 on both sides are (2n-1) π / 6 (n = 1, 2, 3...) Or a range in the vicinity thereof is preferably provided.

  The rotating machine of the present invention is not limited to the above-described embodiment as long as it is within the scope of the present invention, and various forms are applicable. For example, as shown in FIG. 7, an outer rotor type rotating machine in which the stator 20 is provided in the center and the rotor 10 is provided outside may be used. 7 are the same as the corresponding parts of the rotating machine 1 in FIG. 1, and thus the description thereof is omitted.

[3] Manufacturing method of rotating machine
(3-1) Manufacturing Method of Rotor As shown in FIG. 4, the disk 13 is attached to the rotating shaft 11 while the disk covers 13 a and 13 b are overlapped so as to contain the four permanent magnets 12. To fix. Since the disk 13 is fixed to the outer peripheral surface of the rotating shaft 11, the rotor 10 and the rotating shaft 11 rotate integrally. The fixing member 15 is used as a fixing means for the rotating shaft 11 of the disk 13, but the fixing means in the rotating machine of the present invention is not limited to this, and various methods can be used.

(3-2) Method for Manufacturing Stator An example of a method for manufacturing the stator 20 shown in FIG. 5 will be described below with reference to FIGS. 8 (1) and 8 (2). (a) First, a hollow cylindrical core 25 made of nonmagnetic stainless steel or the like having a certain degree of strength is prepared, and (b) a steel sheet rolled into a strip shape is wound. At that time, the steel plate is welded to the core 25 so that the steel plate layer does not peel off after winding, and then the layers of each steel plate are fixed with an adhesive such as epoxy resin while winding. Moreover, it is preferable to fix the terminal of the steel plate after winding by spot welding or the like.

  (c) A hollow cylindrical core 26 made of nonmagnetic stainless steel or the like is placed on the outer periphery of the wound core formed in step (c). At that time, it is preferable to anneal the wound iron core to some extent. Thereby, after being accommodated in the core 26, it is cooled, and the wound core is in close contact with the core 26 by expansion. (d) Cut one end of the wound iron core formed in the step (c) so that the teeth portion 22 is formed in six equal parts. (e) In order to form the tooth winding part 221 around which the coil is wound, the lower part of the tooth part 22 is cut with an end mill or the like. (f) The stator 20 is obtained by cutting off one end of the wound core on the side where the tooth portion 22 is formed. Through the above steps, the stator 20 can be formed integrally, and the tip of the tooth portion 22 can be made flat. Thereby, a stable magnetic flux distribution with low iron loss can be obtained. (g) is a front view of the stator 20 of (f) as viewed from the front A. FIG.

  FIG. 9 shows another example of the method for manufacturing the stator 20 of the present invention. A steel plate wound around the base material 31 is attached to the core 26 via a base 32 by welding. A press machine 33 for punching a part of the steel plate to form the teeth part 22 is installed at the center of the table 32. The core 26 is attached to a winder (not shown) for rotating the core 26.

  First, the core 26 is rotated to wind up the steel plate, and the yoke 21 is formed. Next, after the winder is stopped, the steel plate is punched out by the press machine 33 to form the slot portion 34a. After rotating the winder 60 degrees, the winder is stopped and then the steel plate is punched out by the press machine 33 to form the slot portion 34b. As a result, the width P of the slot portion 34a and the slot portion 34b becomes a length corresponding to 60 degrees of the winder (outer diameter D) around which the steel plate is wound.

  As the steel sheet is wound on the winder, the interval between the slot portions 34 increases, but the slot portions 34 can be formed at intervals of 60 degrees. In this manner, the slot portion 34 is formed in the steel plate by the press machine 33 while rotating the winder by 60 degrees and wound around the winder, thereby being provided between the six slot portions 34. A stator 20 having a six-pole tooth portion 22 can be formed. While winding, an adhesive layer such as an epoxy resin is provided between the steel plates by coating or the like.

After winding to a regular size with a winder, the steel plate is cut and fixed by welding or the like. The obtained wound iron core cuts the portions of t ₁ and t ₂ on both sides while leaving the regular width T (forms a temporary iron core). Here, since the width P of the slot portion 34a and the slot portion 34b is determined based on the outer diameter D of the winder around which the steel plate is wound, the slot portions 34a and 34b are actually wound. There is a difference corresponding to the length L of the steel sheet from the outer diameter of the winder. Therefore, when forming the slot portion 34 by the press machine 33 after the winding machine is stopped, the slot alignment 35 is inserted into the slot portion 34 of the steel sheet wound around the winding machine, and fine adjustment is performed. preferable. Further, after forming the temporary iron core, the slot portion 34 may be adjusted by the slot alignment 35 before or after cutting the portions t ₁ and t ₂ .

  The method for manufacturing the stator 20 of the present invention is not limited to the above-described method, and various methods can be used as long as the characteristics of the stator 20 of the present invention are not impaired.

(3-3) Magnetization Method of Permanent Magnet In the case of the present invention, when the assembly is performed using the magnetized permanent magnet 12, the thrust between the permanent magnet 12 and the stator 20 is assembled when the rotating machine 1 is assembled. Because of the load, assembly is difficult. Therefore, as shown in FIG. 10, it is preferable to magnetize the permanent magnet 12 of the rotor 10 after the rotating machine 1 is assembled. Figure 10 schematically four permanent magnets 12a of the four-pole rotor 10, 12b, 12c, 12d and on both sides of the stator 20a, 20b each six and a tooth portion _{22a 1 ~22a 6, 22b 1 ~22b} 6 of FIG. Instead of a three-phase AC power source, a DC power source is connected to each tooth portion, as shown in FIG. 10, and currents having different directions and sizes are applied to the coils of each tooth portion. The arrow in the figure indicates the direction of the coil, and a double current flows through the double arrow coil as compared with the single arrow coil.

First, after assembling the rotating machine 1 using a permanent magnet material before magnetization, one of the stators 20a and 20b is shifted in the circumferential direction by an electrical angle of 90 degrees and temporarily assembled. At this time, as shown in FIG. 10, the permanent magnet 12a is sandwiched tooth portions 22b _6, 22b ₁ of the tooth portion 22a ₁ and the stator 20b of the stator 20a. Since the direction of the magnetic flux density of each of the tooth portion 22a ₁ and the tooth portions 22b ₆ and 22b ₁ is upward, a magnetic field having an upward combined magnetic flux is applied to the permanent magnet 12a. As a result, the permanent magnet 12a is magnetized so that the top surface is N-pole. On the other hand, the permanent magnet 12b is sandwiched between the tooth portions 22a ₂ and 22a ₃ of the stator 20a and the teeth portion 22b ₂ of the stator 20b. Since the direction of the magnetic flux density of each of the tooth portions 22a ₂ and 22a ₃ and the tooth portion 22b ₂ is downward, a magnetic field having an upward combined magnetic flux is applied to the permanent magnet 12b. Thereby, the permanent magnet 12a is magnetized so that the upper surface becomes an S pole. In contrast, between the permanent magnet 12a and the permanent magnet 12b is because it is sandwiched between the tooth portions 22b ₁ having an upward flux and teeth 22a ₂ having a downward flux, magnetic flux is canceled out.

Similarly, the permanent magnet 12c is sandwiched between the teeth portion 22a _{4 of the} stator 20a having an upward magnetic flux density and the teeth portions 22b ₃ and 22b ₄ of the stator 20b, and the permanent magnet 12a has an upward composite magnetic flux. Since a magnetic field is applied, the permanent magnet 12a is magnetized so that the top surface is N-pole. The permanent magnet 12d is sandwiched between the teeth 22a ₅ and 22a _{6 of the} stator 20a having an upward magnetic flux density and the teeth 22b ₅ of the stator 20b. A magnetic field having a downward composite magnetic flux is applied to the permanent magnet 12a. Therefore, the permanent magnet 12a is magnetized so that the upper surface becomes the S pole. Therefore, as shown in FIG. 10, the permanent magnets 12a, 12b, 12c, and 12d are magnetized so that N-poles and S-poles are alternately arranged in the circumferential direction. After the permanent magnets 12a, 12b, 12c, and 12d are magnetized, one position of the stators 20a and 20b is shifted to the original position and returned to the normal position so that the teeth 22a and 22b of the stators 20a and 20b face each other. . Thereby, the permanent magnets 12a, 12b, 12c, and 12d can be magnetized.

  Thus, in the case of the present invention, even when the poles of the rotor and the stator are different as in the case of the 4-pole rotor 6-pole stator as described above, all permanent magnets are alternated once after the rotating machine is assembled. Can be magnetized so that the polarity changes. Therefore, the rotating machine 1 can be manufactured while suppressing the influence of the thrust load applied between the permanent magnet 12 and the stator 20.

  The bracket 24 for fixing at least one stator 20 may be configured to fix the stator 20 rotatably. As a result, as described above, the position of the winding of the stator 20 is shifted to allow current to flow through the coil 23, and the permanent magnet 12 can be easily magnetized.

  As mentioned above, the rotating machine 1 of the present invention has been described by taking the rotating machine 1 of the 4-pole rotor 6-pole stator as an example. it can. For example, a 6 pole rotor 9 pole stator may be used, and the number of stators is not particularly limited.

It is a fragmentary sectional view which shows the rotary machine which is one Example of this invention. It is a perspective view which shows an example of a rotor and a rotating shaft. (a) is the front view and sectional drawing which show an example of a rotor, (b) is AA sectional drawing. It is sectional drawing which shows an example of a rotor. It is a front view which shows an example of a stator. It is a figure which shows typically arrangement | positioning of a rotor and a stator. It is a fragmentary sectional view which shows the rotary machine which is another Example of this invention. It is a figure which shows an example of the manufacturing method of a stator. It is a figure which shows an example of the manufacturing method of a stator. It is a figure which shows another example of the manufacturing method of a stator. It is a figure which shows an example of the magnetization method of a permanent magnet.

Explanation of symbols

1 ... Rotating machine
10 ... Rotor
11 ... Rotating shaft
12 ... Permanent magnet
13 ... disc
13a, 13b ... disc lid
130 ・ ・ ・ Pocket
131 ・ ・ ・ Edge
132 ・ ・ ・ Flange
133 ... notch
14 ... Bearing
15 ... Fixing material
20, 20a, 20b ... Stator
21 ... Yoke part
22 ... Teeth
221 ... Teeth winding part
222 ... Teeth tip
23, 23a, 23b ... Coil
24 ... Bracket
31 ... Base material
32 ...
33 ... Press machine
34 ・ ・ ・ Slot
35 ... Slot alignment

Claims (2)

A rotating shaft, a rotor connected perpendicularly to the rotating shaft and having a plurality of permanent magnets, and a stator provided on both sides of the rotor via a gap, the stator including a yoke portion; A plurality of teeth portions around which coils are wound, the teeth portions and the yoke portions are integrally formed by a wound iron core ;
The teeth portion includes a teeth winding portion that winds a coil, and a teeth tip portion that is provided at a tip of the teeth winding portion and has a larger diameter than the teeth winding portion.
When the coil is a three-phase coil, the stators on both sides are provided with an electrical angle of (2n−1) π / 6 (n = 1, 2, 3,...) Or in the vicinity thereof. rotating machine characterized in that the are. 2. The rotating machine according to claim 1, wherein the plurality of permanent magnets are alternately arranged with N and S poles in a circumferential direction of the rotor.

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