JP5194984B2 - Permanent magnet rotor - Google Patents

Description

  The present invention relates to a structure of a permanent magnet type rotor in which a plurality of permanent magnets are arranged per magnetic pole on the surface of a rotor core.

Conventionally, permanent magnet type rotors include a surface magnet type rotor in which permanent magnets are arranged on the surface of a rotor core and an embedded magnet type rotor in which permanent magnets are embedded in the rotor core.
FIG. 12 is a schematic configuration diagram of the permanent magnet type motor 100 and shows an example of 12 poles. A permanent magnet type motor 100 shown in FIG. 12 includes a stator 200 configured by winding a winding 202 around a stator core 201, and a surface magnet type rotor arranged with an air gap on the inner periphery of the stator 200. 300A. In the surface magnet type rotor 300 </ b> A, an S-pole permanent magnet 301 a on the rotor outer side and an N-pole permanent magnet 302 a on the rotor outer side are alternately arranged in the circumferential direction of the rotor core 310. In addition, the arrow shown in FIG. 12 has shown the direction of magnetization. The permanent magnet type motor 100 rotates the surface magnet type rotor 300A by causing an alternating current to flow through the winding 202 of the stator 200 to generate a rotating magnetic field.

In the conventional permanent magnet type motor, for the purpose of improving torque and efficiency, the polar anisotropic rotor 300B shown in FIG. 13 (see Patent Document 1) and the Halbach magnet array rotor 300C shown in FIG. 14 (see Patent Document 2). It is known to use.
In the polar anisotropic rotor 300B shown in FIG. 13, the magnetic flux is concentrated on the magnetic pole center by magnetization of the permanent magnet 301b. Further, in the Halbach magnet array rotor 300C shown in FIG. 14, the permanent magnets 301c, 302c, 303c, and 304c magnetized in the direction of the arrow shown on the surface of the rotor core 310 are arranged as shown in FIG. To focus on. In these conventional examples, the torque is increased and the efficiency is improved by concentrating the magnetic flux at the center of the magnetic pole to increase the amount of magnetic flux.

On the other hand, the embedded magnet type rotor is designed to improve efficiency by using a reluctance torque by embedding a permanent magnet from the surface of the rotor core to the inside, and FIG. 15 shows an example of four poles of the embedded magnet type rotor 300D. . In the embedded magnet type rotor 300D shown in FIG. 15, when torque is generated by passing a current through a stator winding (not shown), the action of the magnetic flux of the permanent magnet 301d and the magnetic flux generated by the winding Since the magnetic flux concentrates toward the end of the rotor magnetic pole part, there is a problem that efficiency is lowered due to magnetic saturation, an increase in iron loss, and the like. To solve this problem, the magnetic flux concentrates toward the end of the rotor magnetic pole part by the rectifying action that restricts the path of the magnetic flux by providing a plurality of slits in the rotor magnetic pole part, thereby improving the efficiency. Is known (see Patent Document 3).
JP 2006-311777 A JP 2007-221911 A Japanese Patent Laid-Open No. 10-285845

However, the conventional surface magnet type rotor has permanent magnets arranged around the entire surface of the rotor core and does not use a high magnetic permeability material such as iron as a magnetic pole, so there is a limit in concentrating the magnetic flux of the magnet. In addition, there is a problem that the magnetic flux generated from the magnet cannot be effectively used, and the torque and efficiency of the motor cannot be sufficiently improved.
On the other hand, a conventional embedded magnet type rotor has a narrow magnetic path by providing a slit in the rotor magnetic pole portion. Therefore, especially when using a neodymium magnet with a high magnetic flux density or when a large current is passed through a winding. There is a problem that the amount of magnetic flux is reduced as compared with the case where there is no slit, and the torque of the motor is reduced. Furthermore, when the width of the slit is not sufficiently wide, there is a problem that the leakage magnetic flux between the slits becomes remarkable and the rectifying action of the slit is weakened. On the contrary, if the width of the slit is sufficiently wide, there arises a problem that the amount of magnetic flux is remarkably lowered.
The present invention has been made based on the above circumstances, and an object of the present invention is to provide a permanent magnet rotor capable of improving the torque and efficiency of a motor by effectively utilizing magnetic flux.

(Invention of Claim 1)
The present invention includes an annular rotor core configured by stacking a plurality of disk-shaped core sheets made of a high permeability material, and a plurality of magnetic poles formed on the surface of the rotor core. A permanent magnet type rotor configured by arranging a plurality of hitting permanent magnets and a plurality of core pieces, wherein the plurality of core pieces are a first core piece and a second core piece arranged at intervals in the circumferential direction. The first core piece and the second core piece each have a polygonal cross-sectional shape in the radial direction, one side appears on the rotor surface, and the other side is a permanent magnet. The plurality of permanent magnets arranged in contact with each other includes a first magnet disposed between the first core piece and the second core piece in the circumferential direction, and the first core together with the first magnet. And a second magnet disposed in contact with the other side of the piece and the second core piece, the first magnet being a rotor Is magnetized along a radial direction of the A, the second magnet is magnetized along a direction perpendicular to the contact surface between the first core piece and a second core piece, the first core piece and the Each of the two core pieces is formed such that the area of the portion in contact with the second magnet is larger than the area of the portion appearing on the rotor surface, and a plurality of core pieces per magnetic pole are integrally formed on the core sheet. In addition, a plurality of magnet insertion holes for arranging a plurality of permanent magnets are formed, and a connection portion that connects the rotor core and the plurality of core pieces, and a connection portion that connects the plurality of core pieces to each other It is provided integrally.

According to the above configuration, the core piece made of a high permeability material is used for a part of the magnetic pole, and the area of the core piece in contact with the second magnet is larger than the area of the core piece appearing on the rotor surface. The magnetic flux acting on the torque can be increased. As a result, the magnetic flux of the permanent magnet can be effectively used, and the torque and efficiency of the motor can be improved.
Further, by disposing the first magnet between the first core piece and the second core piece in the circumferential direction, it is possible to suppress the deviation of the magnetic flux density by the rectifying action, and the first core piece and the second core piece can be suppressed . by wider gap between the core piece (circumferential width of the first magnet), thereby reducing the leakage magnetic flux between the first core piece and the second core piece. Furthermore, since the magnetic flux can be increased by disposing the first magnet between the first core piece and the second core piece , where the magnetic flux usually decreases with a wide slit, the rectifying action and leakage magnetic flux can be increased. In addition to the reduction, the magnetic flux can be increased, and the torque and efficiency of the motor can be improved.
Furthermore, since a plurality of core pieces are integrally formed per magnetic pole and a plurality of magnet insertion holes are formed in the core sheet, it is not necessary to assemble the rotor core and the plurality of core pieces, and magnet insertion Since the rotor can be assembled only by arranging the permanent magnets in the holes, the assembly of the rotor is facilitated and the productivity can be improved.
In addition, the core sheet is integrally provided with a connecting portion that connects the rotor core and the plurality of core pieces, and a connecting portion that connects the plurality of core pieces, so the mechanical strength of the rotor can be improved and high rotation speed is achieved. It can be rotated to the area.

  The best mode for carrying out the present invention will be described in detail with reference to the following examples.

FIG. 1 is a schematic view of a permanent magnet type rotor 1A according to the first embodiment, and FIG. 2 is an enlarged view of a rotor magnetic pole portion shown in FIG.
As shown in FIG. 1, the permanent magnet type rotor 1 </ b> A of the present embodiment has an annular rotor core 2 made of a high permeability material such as iron, and 12 poles of magnetic poles are formed on the surface of the rotor core 2. The
The 12 magnetic poles are configured by alternately arranging magnetic poles having different polarities one by one, but the two magnetic poles adjacent to each other in the circumferential direction, that is, one magnetic pole pair, have the same magnetic pole structure except that the polarities are different. Therefore, hereinafter, one magnetic pole 2A will be described with reference to FIG.

The magnetic pole 2A is composed of three permanent magnets 30A, 31A, 32A and two core pieces 40A, 41A made of a high permeability material such as iron.
The three permanent magnets 30 </ b> A to 32 </ b> A are composed of one first magnet 30 </ b> A disposed in the central portion in the circumferential direction and two second magnets disposed on both sides in the circumferential direction of the first magnet 30 </ b> A. 31A and 32A.
The first magnet 30A is formed such that both side surfaces in the circumferential direction are formed along the radial direction of the rotor 1A, the end surface on the inner peripheral side is in contact with the surface of the rotor core 2, and the end surface on the outer peripheral side is the surface of the rotor 1A. It is appearing in.

Each of the second magnets 31A and 32A has the same height as that of the first magnet 30A in the radial direction of the rotor 1A, and the inner peripheral end face of the rotor core 2 is the same as the first magnet 30A. The end face on the outer peripheral side appears on the surface of the rotor 1A.
The side surfaces on the outer side in the circumferential direction of the second magnets 31A and 32A, that is, the side surfaces not in contact with the first magnet 30A are formed along the radial direction of the rotor 1A from the inner peripheral end to the outer peripheral end. The side surfaces on the inner side in the circumferential direction of the two magnets 31A and 32A, that is, the side surface in contact with the first magnet 30A, are formed along the radial direction of the rotor 1A from the inner peripheral end to the middle toward the outer peripheral end. From the outer periphery to the outer peripheral end is inclined in a direction away from the first magnet 30A. That is, the second magnets 31A and 32A are arranged so that only the inner peripheral side formed along the radial direction of the rotor 1A is in contact with the first magnet 30A among the side surfaces on the inner side in the circumferential direction. A substantially triangular space is formed between the inclined surface inclined in the direction away from the magnet 30A and the circumferential side surface of the first magnet 30A.

The core piece 40A is the first core piece or the second core piece of the present invention, and is disposed in a substantially triangular space formed between the first magnet 30A and the second magnet 31A. The first magnet 30A is provided in a substantially triangular shape having a surface 40a in contact with the side surface in the circumferential direction, a surface 40b in contact with the inclined surface of the second magnet 31A, and a surface 40c appearing on the surface of the rotor 1A.
Similarly, the core piece 41A is the second core piece or the first core piece of the present invention, and is arranged in a substantially triangular space formed between the first magnet 30A and the second magnet 32A. The surface 41a that contacts the circumferential side surface of the first magnet 30A, the surface 41b that contacts the inclined surface of the second magnet 32A, and the surface 41c that appears on the surface of the rotor 1A are provided in a substantially triangular shape. .

That is, the core pieces 40A and 41A are disposed only on the outer peripheral side of the magnetic pole 2A where a substantially triangular space is formed, and are not disposed on the inner peripheral side of the magnetic pole 2A. In other words, the core piece 40A is disposed between the first magnet 30A and the second magnet 31A on the outer peripheral side of the magnetic pole 2A, and the core piece is provided between the first magnet 30A and the second magnet 32A. 41A is arranged on the inner peripheral side of the magnetic pole 2A, between the first magnet 30A and the second magnet 31A, and between the first magnet 30A and the second magnet 32A, respectively. The core pieces 40A and 41A are not arranged, and the first magnet 30A and the second magnet 31A, and the first magnet 30A and the second magnet 32A are in contact with each other in the circumferential direction.
The second magnets 31A and 32A and the core pieces 40A and 41A are symmetrically arranged in the circumferential direction with the first magnet 30A interposed therebetween.

Next, the magnetization direction of the permanent magnets (first magnet 30A, second magnets 31A, 32A) will be described.
The first magnet 30A is magnetized inward in the radial direction as indicated by an arrow in the figure.
Second magnets 31A, 32A is, as indicated by the arrow, is magnetized along the inclined surface and a straight direction orthogonal. The direction of magnetization is opposite to that of the core pieces 40A and 41A. The magnetic pole 2A acts as an S pole by the first magnet 30A and the second magnets 31A and 32A. The other magnetic poles adjacent in the circumferential direction act as N poles because the first magnet 30A and the second magnets 31A, 32A are magnetized in the opposite direction to the magnetic pole 2A.
A stator (not shown) is arranged outside the radial direction of the rotor 1A of this embodiment via an air gap. When a rotating magnetic field is generated by passing an alternating current through the winding of the stator, the magnetic field generated by the rotor 1A and the stator Torque is generated by the interaction with the rotating magnetic field generated by the rotor 1A, and the rotor 1A rotates.

Subsequently, an operation in which the magnetic fluxes of the second magnets 31A and 32A are concentrated on the air gap portions of the core pieces 40A and 41A will be described.
As can be seen from the structure of the magnetic pole 2A, the area of the core piece 40A on which the magnetic flux of the second magnet 31A acts (the area of the surface 40b in contact with the inclined surface of the second magnet 31A) is the core piece 40A in contact with the air gap portion. Therefore, the magnetic flux of the second magnet 31A is concentrated on the surface 40c through the core piece 40A through the surface 40b, and the magnetic flux acts on the air gap portion. Similarly, the area of the core piece 41A on which the magnetic flux of the second magnet 32A acts (the area of the surface 41b) is larger than the area of the core piece 41A in contact with the air gap part (the area of the surface 41c). The magnetic flux of 32A is concentrated on the surface 41c through the core piece 41A through the surface 41b, and the magnetic flux acts on the air gap portion.

Next, the rectifying action of the magnetic flux will be described with reference to FIG.
FIG. 3 shows a change in magnetic flux density when a current is applied due to the first magnet 30A being disposed between the core piece 40A and the core piece 41A.
When no magnet is arranged between the core piece 40A and the core piece 41A, that is, as shown in FIG. 4, an iron piece 42A (high permeability material) is arranged between the core piece 40A and the core piece 41A. When the core piece 40A and the core piece 41A are integrally formed through the iron piece 42A (however, the magnet 33A is arranged on the portion in contact with the surface of the rotor core 2, and the arrow in the figure indicates the direction of magnetization) As shown by the broken line in FIG. 3, the magnetic flux density is biased toward the direction of the generated torque. Specifically, when the rotation direction of the rotor 1A is counterclockwise as indicated by the arrow in the figure, the magnetic flux is biased toward the core piece 41A due to the influence of the current flowing through the stator. In FIG. 3, it corresponds to around an electrical angle of 30 ° and 120 °.
On the other hand, when the first magnet 30A is arranged between the core piece 40A and the core piece 41A, as shown by the solid line in FIG. Approaching the state of distribution. This is the magnetic flux rectification action.

Moreover, the leakage magnetic flux between 40 A of core pieces and 41 A of core pieces is reduced by forming the space | interval of 40 A of core pieces, and 41 A of core pieces, ie, the circumferential direction width | variety of the 1st magnet 30A, to some extent. Further, the first magnet 30A is disposed between the core piece 40A and the core piece 41A, thereby compensating for a decrease in the amount of magnetic flux due to an increase in the interval between the core piece 40A and the core piece 41A.
As described above, the rotor 1A according to the present embodiment effectively uses the magnetic flux concentration action, the magnetic flux rectification action, and the leakage magnetic flux reduction action to effectively use the magnetic flux generated from the first magnet 30A and the second magnets 31A and 32A. Because it can be utilized, the magnetic flux can be increased compared to the conventional surface magnet type rotor, and the magnetic flux rectifying action and leakage magnetic flux reducing action can be increased as compared with the conventional embedded magnet type rotor, so that the motor torque and efficiency are improved. Is possible.

FIG. 5 is a schematic view of a permanent magnet type rotor 1B according to the second embodiment, and FIG. 6 is an enlarged view of the rotor magnetic pole portion shown in FIG.
As shown in FIG. 5, the rotor 1 </ b> B of the present embodiment has 12 magnetic poles formed on the surface of the rotor core 2, and each magnetic pole has two permanent magnets 30 </ b> B, 31 </ b> B, 32 </ b> B, 33 </ b> B. Core pieces 40B and 41B. Note that the 12 magnetic poles are configured by alternately arranging magnetic poles having different polarities one by one as in the first embodiment, and two magnetic poles adjacent to each other in the circumferential direction, that is, one magnetic pole pair, are different in polarity. The structure of the magnetic pole is the same.

The four permanent magnets 30B to 33B include a first magnet 30B disposed at the circumferential center of the magnetic pole 2B, a second magnet 31B disposed on the inner circumferential side of the first magnet 30B, and a magnetic pole. It is comprised with the 2nd magnets 32B and 33B arrange | positioned at the circumferential direction both sides of 2B.
The first magnet 30B is provided with the same height as the two core pieces 40B and 41B in the radial direction, and both side surfaces in the circumferential direction are formed along the radial direction of the rotor 1B. Appears on the surface of the rotor 1B.

The second magnet 31B is provided in an arc shape along the surface of the rotor core 2, and the length in the circumferential direction is longer than that of the first magnet 30B. In addition, the 1st magnet 30B is located in the circumferential direction center part of the 2nd magnet 31B.
The second magnets 32B and 33B are arranged such that both side surfaces in the circumferential direction are formed along the radial direction of the rotor 1B, the end surfaces on the inner peripheral side are in contact with the surface of the rotor core 2, and the end surfaces on the outer peripheral side are It appears on the surface of the rotor 1B. The second magnets 32B and 33B can be provided in common with the second magnets 32B and 33B of other magnetic poles adjacent in the circumferential direction.

The core piece 40B is the first core piece or the second core piece of the present invention, and is in a substantially rectangular space surrounded by the first magnet 30B, the second magnet 31B, and the second magnet 32B. The surface 40a that is disposed and contacts the circumferential side surface of the first magnet 30B, the surface 40b that contacts the outer circumferential surface of the second magnet 31B, the surface 40c that contacts the circumferential side surface of the second magnet 32B, and the rotor 1B It is provided in a substantially rectangular shape having a surface 40d appearing on the surface.
Similarly, the core piece 41B is the second core piece or the first core piece of the present invention, and has a substantially rectangular shape surrounded by the first magnet 30B, the second magnet 31B, and the second magnet 33B. A surface 41a in contact with the circumferential side surface of the first magnet 30B, a surface 41b in contact with the outer circumferential surface of the second magnet 31B, a surface 41c in contact with the circumferential side surface of the second magnet 33B, It is provided in a substantially rectangular shape having a surface 41d that appears on the surface of the rotor 1B. That is, the two core pieces 40B and 41B are disposed only on the outer peripheral side of the magnetic pole 2B, and are not disposed on the inner peripheral side of the magnetic pole 2B.

Next, the magnetization directions of the permanent magnets (first magnet 30B, second magnets 31B, 32B, 33B) will be described.
The first magnet 30B and the second magnet 31B are each magnetized inward in the radial direction, as indicated by arrows in the drawing.
The second magnet 32B is magnetized in the clockwise direction along the circumferential tangential direction as indicated by the arrow in the figure, and the second magnet 33B is oriented in the circumferential tangential direction as indicated by the arrow in the figure. Is magnetized in the counterclockwise direction.
By the first magnet 30B and the second magnets 31B, 32B, 33B, the magnetic pole 2B acts as an S pole. The other magnetic pole adjacent in the circumferential direction acts as an N pole.

As can be seen from the structure of the magnetic pole 2B, the area of the core piece 40B on which the magnetic flux of the second magnets 31B and 32B acts (the area of the surface 40b in contact with the outer peripheral surface of the second magnet 31B + the second magnet 32B). The area of the surface 40c in contact with the side surface in the circumferential direction) is larger than the area of the core piece 40B in contact with the air gap part (the area of the surface 40d appearing on the surface of the rotor 1B), so that the magnetic fluxes of the second magnets 31B and 32B respectively A magnetic flux acts on the air gap portion by concentrating on the surface 40d via the core piece 40B through the surface 40b and the surface 40c.
Similarly, the area of the core piece 41B on which the magnetic flux of the second magnets 31B and 33B acts (the area of the surface 41b in contact with the outer peripheral surface of the second magnet 31B + the surface 41c in contact with the circumferential side surface of the second magnet 33B). Area) is larger than the area of the core piece 41B in contact with the air gap portion (the area of the surface 41d appearing on the surface of the rotor 1B), so that the magnetic flux of the second magnets 31B and 33B passes through the surface 41b and the surface 41c, respectively. The magnetic flux acts on the air gap portion through 41B and concentrates on the surface 41d.
Since the rectifying action of magnetic flux and the reducing action of leakage magnetic flux are the same as those in the first embodiment, the description thereof is omitted.

  As described above, the rotor 1B according to the present embodiment causes the magnetic flux generated from the first magnet 30B and the second magnets 31B, 32B, and 33B to be generated by the magnetic flux concentration action, the magnetic flux rectification action, and the leakage flux reduction action. Since the magnetic flux can be effectively utilized, the magnetic flux can be increased from the conventional surface magnet type rotor, and the magnetic flux rectifying action and the leakage magnetic flux reducing action can be increased as compared with the conventional embedded magnet type rotor. Efficiency can be improved.

FIG. 7 is a schematic view of a permanent magnet type rotor 1C according to the third embodiment, and FIG. 8 is an enlarged view of the rotor magnetic pole portion shown in FIG.
As shown in FIG. 7, the rotor 1 </ b> C of the present embodiment has 12 magnetic poles formed on the surface of the rotor core 2, and each magnetic pole includes five permanent magnets 30 </ b> C, 31 </ b> C, 32 </ b> C, 33 </ b> C, 34 </ b> C, It is composed of three core pieces 40C, 41C, and 42C. Note that the 12 magnetic poles are configured by alternately arranging magnetic poles having different polarities one by one as in the first embodiment, and two magnetic poles adjacent to each other in the circumferential direction, that is, one magnetic pole pair, are different in polarity. The structure of the magnetic pole is the same.

The five permanent magnets 30C to 34C include two magnets 30C and 31C disposed on the outer peripheral side of the magnetic pole 2C, one magnet 32C disposed on the inner peripheral side of the magnetic pole 2C, and the circumferential direction of the magnetic pole 2C. It is composed of two magnets 33C and 34C arranged on both sides.
The two magnets 30C and 31C are each provided in an L shape and are arranged in opposite directions in the circumferential direction, and one end surface of the L shape contacts the circumferential side surface of the two magnets 33C and 34C, respectively. The other end face appears on the surface of the rotor 1C.
The magnets 32 </ b> C are arranged in an arc shape along the surface of the rotor core 2, and both end surfaces in the circumferential direction are in contact with the circumferential side surfaces of the two magnets 33 </ b> C and 34 </ b> C, respectively.
The magnets 33C and 34C are formed such that both side surfaces in the circumferential direction are formed along the radial direction of the rotor 1C, end surfaces on the inner peripheral side are in contact with the surface of the rotor core 2, and end surfaces on the outer peripheral side are on the surface of the rotor 1C. Appears. The magnets 33C and 34C can be provided in common with other magnetic pole magnets 33C and 34C adjacent in the circumferential direction.

The three core pieces 40C to 42C are one core piece 40C provided in a convex shape and two core pieces arranged at predetermined intervals on both sides in the circumferential direction of the convex portion of the core piece 40C. 41C and 42C. In the third embodiment, one core piece 40C is the first core piece or the second core piece of the present invention, and the two core pieces 41C and 42C are respectively the second core piece of the present invention. Or it is the 1st core piece.
The core piece 40C is disposed between the two magnets 30C, 31C and the magnet 32C, and both end faces 40a, 40b in the circumferential direction on which the magnetic fluxes of the magnets 33C, 34C act are circumferential directions of the magnets 33C, 34C, respectively. The end face 40c on the outer peripheral side appears on the surface of the rotor 1C.

41 C of core pieces are arrange | positioned in the substantially square-shaped space enclosed by the L-shaped magnet 30C and the magnet 33C, and contact | connect the surface (no code | symbol) which contact | connects the circumferential direction side surface of the magnet 30C, and the outer peripheral surface of the magnet 30C. The surface 41a, the surface 41b in contact with the circumferential side surface of the magnet 33C, and the surface 41c appearing on the surface of the rotor 1C are provided in a substantially rectangular shape. Similarly, the core piece 42C is disposed in a substantially quadrangular space surrounded by the L-shaped magnet 31C and the magnet 34C, and has a surface (no reference numeral) in contact with the circumferential side surface of the magnet 31C and an outer periphery of the magnet 31C. It is provided in a substantially rectangular shape having a surface 42a that contacts the surface, a surface 42b that contacts the circumferential side surface of the magnet 34C, and a surface 42c that appears on the surface of the rotor 1C.
That is, the two core pieces 41C and 42C are disposed only on the outer peripheral side of the magnetic pole 2C, and are not disposed on the inner peripheral side of the magnetic pole 2C.

Next, the magnetization direction of the permanent magnets (magnets 30C to 34C) will be described.
The L-shaped magnets 30C, 31C and the magnet 32C are each magnetized inward in the radial direction, as indicated by arrows in the figure.
The magnet 33C is magnetized in the clockwise direction along the circumferential tangential direction as indicated by the arrow in the figure, and the magnet 34C is counterclockwise along the circumferential tangential direction as indicated by the arrow in the figure. Is magnetized.
The magnetic pole 2C acts as an S pole by the magnets 30C to 34C. The other magnetic pole adjacent in the circumferential direction acts as an N pole.

In the magnet 30C, a portion (a portion extending in the radial direction) arranged between the convex portion of the core piece 40C and the core piece 41C in the circumferential direction functions as the first magnet of the present invention, and the core piece in the radial direction. 40C a portion disposed between the core pieces 41 C (the portion extending in the circumferential direction) acts as the second magnet. Similarly, in the magnet 31C, a portion (a portion extending in the radial direction) disposed between the convex portion of the core piece 40C and the core piece 42C in the circumferential direction functions as the first magnet of the present invention, and the core in the radial direction A portion (a portion extending in the circumferential direction) disposed between the piece 40C and the core piece 42C serves as a second magnet. The magnet 32C and the magnets 33C and 34C each function as a second magnet of the present invention.

As can be seen from the structure of the magnetic pole 2C, the core piece 41C has an area where the magnetic fluxes of the magnets 30C and 33C act (area of the surface 41a in contact with the magnet 30C + area of the surface 41b in contact with the magnet 33C). The magnetic flux of the magnets 30C and 33C is concentrated on the surface 41c through the core piece 41C through the surface 41a and the surface 41b, respectively, in the air gap portion. Magnetic flux acts.
The core piece 42C has an area where the magnetic flux of the magnets 31C and 34C acts (the area of the surface 42a in contact with the magnet 31C + the area of the surface 42b in contact with the magnet 34C) in contact with the air gap portion (on the surface of the rotor 1C). Thus, the magnetic fluxes of the magnets 31C and 34C are concentrated on the surface 42c through the core pieces 42C through the surfaces 42a and 42b, respectively, and the magnetic flux acts on the air gap portion.
Similarly, in the core piece 40C, the area on which the magnetic fluxes of the magnets 30C to 34C act is larger than the area in contact with the air gap portion (the area of the surface 40c that appears on the surface of the rotor 1C). The magnetic flux acts on the air gap portion by concentrating on 40c.
Since the rectifying action of magnetic flux and the reducing action of leakage magnetic flux are the same as those in the first embodiment, the description thereof is omitted.

  As described above, the rotor 1C of the present embodiment can effectively utilize the magnetic flux generated from the magnets 30C to 34C by the magnetic flux concentration action, the magnetic flux rectification action, and the leakage magnetic flux reduction action. Since the magnetic flux can be increased from the rotor, and the magnetic flux rectifying action and the leakage magnetic flux reducing action can be increased as compared with the conventional embedded magnet rotor, the motor torque can be improved and the efficiency can be improved. In addition, since the three core pieces 40C, 41C, and 42C exist in one magnetic pole, the magnetic flux distribution becomes smoother than in the first or second embodiment, and the cogging torque and torque ripple can be reduced.

FIG. 9 is a schematic view of a permanent magnet type rotor 1D according to the fourth embodiment, and FIG. 10 is an enlarged view of the rotor magnetic pole portion shown in FIG.
The fourth embodiment is a modification of the second embodiment, and the basic configuration and effects of the rotor 1D shown in FIG. 9 are the same as those of the second embodiment, so that the description thereof will be omitted and only different parts will be described.
The difference from the second embodiment is that, as shown in FIG. 10, the rotor core 2 and the two core pieces 40D and 41D and the core pieces 40D and 41D are connected to each other by the connecting portions, and the second The magnets 32D and 33D are divided into two in the circumferential direction, and a connecting portion exists between the two divided magnets.

Specifically, the rotor core 2 and the core pieces 40D and 41D are connected by connection portions 50 and 51, respectively. Further, the core piece 40D and the core piece 41D are connected by the connecting portions 52 and 53. Further, adjacent magnetic poles are also connected by the connecting portion 54. Further, the connection part 54 between the magnetic poles and the rotor core 2 are connected by a connection part 55.
Said rotor 1D is comprised by laminating | stacking several disk shaped core sheets 10 (refer FIG. 11) formed from soft magnetic materials, such as a silicon steel plate, for example. As shown in FIG. 11, in the core sheet 10, a magnet insertion hole 11 for arranging the first magnet 30D, a magnet insertion hole 12 for arranging the second magnet 31D, and a second magnet 32D are arranged. A magnet insertion hole 13 for arranging the second magnet 33D and a magnet insertion hole 14 for arranging the second magnet 33D are formed. In addition to the magnet insertion holes 11 to 14, a portion 20 for forming the rotor core 2 and two core pieces Sites 40 and 41 forming 40D and 41D and connection portions 50 to 55 are provided.

According to said structure, since intensity | strength can be ensured with respect to a centrifugal force, while being able to use to higher rotation, high productivity can be acquired by punching the core sheet | seat 10. FIG. Further, if a composite magnetic material (a material capable of creating a magnetic part and a non-magnetic part by using different structures in the same material) is used for the core sheet 10, leakage can be caused by making the connecting part non-magnetic. Since the magnetic flux can be reduced, the power factor is improved, and motor torque and efficiency can be improved.
Further, in the structure of the rotor 1B described in the second embodiment, a means such as winding a high-strength metal cover or a reinforcing fiber around the rotor surface is required. No means such as winding reinforcing fibers is required.
In addition, although the present Example described as a modification of Example 2, it can be comprised similarly as a modification of Example 1 or Example 3. FIG.

(Modification)
The present invention is not limited to the first to fourth embodiments described above, and various modifications can be made within the scope of the gist of the present invention. For example, in the first to fourth embodiments described above, the 12-pole rotors 1 </ b> A to 1 </ b> D have been described.
In the first to fourth embodiments, the so-called inner rotor type in which the rotors 1A to 1D are located inside the stator has been described. However, the rotor 1A to 1D is an outer rotor type in which the rotors 1A to 1D are located outside the stator. The present invention can also be applied to an axial gap type in which the stator is disposed in the axial direction.

Schematic of a permanent magnet type rotor (Example 1). (Example 1) which is an enlarged view of the rotor magnetic pole part shown in FIG. It is the schematic diagram which showed the magnetic flux density distribution on the rotor surface for one magnetic pole pair. It is an enlarged view of a rotor magnetic pole part. Schematic of a permanent magnet type rotor (Example 2). (Example 2) which is an enlarged view of the rotor magnetic pole part shown in FIG. Schematic of a permanent magnet type rotor (Example 3). (Example 3) which is an enlarged view of the rotor magnetic pole part shown in FIG. Schematic of a permanent magnet type rotor (Example 4). (Example 4) which is an enlarged view of the rotor magnetic pole part shown in FIG. (Example 4) which is a partial top view of a core sheet. It is a schematic diagram of a permanent magnet type motor (prior art). It is the schematic of a polar anisotropic rotor (prior art). It is the schematic of a Halbach magnet arrangement | sequence rotor (prior art). It is the schematic of an embedded magnet type | mold rotor (prior art).

Explanation of symbols

1A Permanent magnet type rotor according to Example 1 1B Permanent magnet type rotor according to Example 2 1C Permanent magnet type rotor according to Example 3 1D Permanent magnet type rotor according to Example 4 2 Rotor core 10 Core sheet 11-14 Magnet insertion Hole 20 Part for forming rotor core 30A First magnet (Example 1)
31A Second magnet (Example 1)
32A Second magnet (Example 1)
40 A part for forming a core piece 40A Core piece (Example 1)
41 Site for forming a core piece 41A Core piece (Example 1)
50-55 connection

Claims (1)

An annular rotor core configured by laminating a plurality of disk-shaped core sheets made of a high permeability material; and
A permanent magnet rotor having a plurality of magnetic poles formed on the surface of the rotor core and configured by arranging a plurality of permanent magnets and a plurality of core pieces per magnetic pole;
The plurality of core pieces have a first core piece and a second core piece that are spaced apart in the circumferential direction, and the first core piece and the second core piece each have a diameter. The cross-sectional shape of the direction is provided in a polygon, one side of which appears on the rotor surface, the other side is arranged in contact with the permanent magnet,
The plurality of permanent magnets includes a first magnet disposed between the first core piece and the second core piece in a circumferential direction, and the first core piece and the first magnet, A second magnet disposed in contact with the other side of the second core piece,
The first magnet is magnetized along a radial direction of the rotor core;
The second magnet is magnetized along a direction perpendicular to a contact surface between the first core piece and the second core piece,
Each of the first core piece and the second core piece is formed such that an area of a portion in contact with the second magnet is larger than an area of a portion appearing on the rotor surface,
The core sheet is integrally formed with the plurality of core pieces per magnetic pole, and has a plurality of magnet insertion holes for arranging the plurality of permanent magnets, and the rotor core and the plurality of cores A permanent magnet rotor, wherein a connecting portion for connecting the pieces and a connecting portion for connecting the plurality of core pieces are integrally provided.

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