JP2015023726A - Rotor and motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor and a motor that contributes to high output.SOLUTION: A rotor comprises: first and second rotor cores 31, 32 in which a plurality of pawl-like magnetic poles 31b, 32b are projected at equal intervals on the outer peripheral parts of the core bases 31a, 32a, each of which has an approximately disk shape, and also extended in an axial direction; and an annular magnet 33 in which the pawl-like magnetic poles 31b, 32b are functioned as different magnetic poles. When the outside diameter of an assembly in which the first rotor core 31, the second rotor core 32, and the annular magnet 33 are fitted together is represented by Do, the inside diameter thereof is represented by Di, and the length thereof in the axial direction is represented by Hr, the rotor is configured to satisfy the range of 0<Di/Do<0.56 (0.2≤Hr/Do≤0.3) and the range of 0.06<Hr/Do<0.96 (0<Di/Do≤0.2).

Description

  The present invention relates to a rotor and a motor.

  The rotor used in the motor includes two rotor cores combined with each other having a plurality of claw-shaped magnetic poles in the circumferential direction, and a field magnet arranged between them, and each claw-shaped magnetic pole is alternately arranged. There is a so-called permanent magnet field Landell-type rotor that allows different magnetic poles to function.

  And in the rotor of patent document 1, the leakage magnetic flux in a rotor is reduced by providing the interpolar magnet magnetized in the circumferential direction between each circumferential direction of claw-shaped magnetic poles.

JP 2012-115085 A

  By the way, in the rotor of the Landell type structure as described above, it is possible to suppress the leakage magnetic flux in the rotor by providing an interpole magnet, thereby contributing to the improvement of the output. Improvement is desired.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a rotor and a motor that can contribute to higher output.

  Each of the rotors that solve the above-described problems has a plurality of claw-shaped magnetic poles projecting radially outward at equal intervals on the outer periphery of a substantially disk-shaped core base and extending in the axial direction. Are arranged between the first and second rotor cores in which the claw-shaped magnetic poles are alternately arranged in the circumferential direction while being opposed to each other and the axial direction of the core bases, and are magnetized in the axial direction, whereby the first rotor core A field magnet that causes the claw-shaped magnetic pole of the second rotor core to function as a first magnetic pole and the claw-shaped magnetic pole of the second rotor core to function as a second magnetic pole. (2) When the outer diameter of the assembly in which the rotor core and the field magnet are assembled is Do, the inner diameter is Di, and the length in the axial direction is Hr, 0 <Di / Do <0.56 (provided that 0.2 ≦ Hr / Do ≦ 0.3) or 0.06 Hr / Do <0.96 (provided that, 0 <Di / Do ≦ 0.2) configured so as to satisfy the range of.

According to this configuration, as shown in FIG. 5 or FIG. 6, a higher output can be obtained than a so-called SPM (Surface Permanent Magnet) type rotor, which can contribute to higher output.
In the above rotor, the assembly is in a range of 0 <Di / Do ≦ 0.4 (where 0.2 ≦ Hr / Do ≦ 0.3), or 0.1 ≦ Hr / Do <0.65 ( However, it is preferably configured to satisfy the range of 0 <Di / Do ≦ 0.2).

According to this configuration, as shown in FIG. 5 or FIG. 6, it is possible to obtain a higher output than the so-called SPM type rotor, which can contribute to further higher output.
In the rotor, the assembly is in a range of 0 <Di / Do ≦ 0.1 (where 0.2 ≦ Hr / Do ≦ 0.3), or 0.2 ≦ Hr / Do <0.3 ( However, it is preferably configured to satisfy the range of 0 <Di / Do ≦ 0.2).

According to this configuration, as shown in FIG. 5 or FIG. 6, it is possible to obtain a higher output than the so-called SPM type rotor, which can contribute to further higher output.
A motor that solves the above problem includes a rotor having any one of the above-described configurations.

  According to this configuration, it is possible to provide a motor that exhibits the same effect as any of the above effects.

  The rotor and motor of the present invention can contribute to higher output.

It is sectional drawing of the motor in embodiment. It is a top view of the motor in the same as the above. (A) (b) is a perspective view of the rotor in the same as the above. It is sectional drawing of a rotor. It is a graph which shows the torque change at the time of changing the ratio of the axial direction length of an assembly | attachment, and an outer diameter. It is a graph which shows the torque change at the time of changing the ratio of the internal diameter of an assembly | attachment body, and an outer diameter. It is a partial cross section perspective view which shows an example of the conventional motor.

Hereinafter, an embodiment of the motor will be described.
As shown in FIG. 1, a motor case 12 of a brushless motor 11 as a motor includes a yoke housing 13 formed in a substantially bottomed cylindrical shape, and an opening on the front side (left side in FIG. 1) of the yoke housing 13. And an end plate 14 for closing. The yoke housing 13 is made of, for example, magnetic iron. The end plate 14 is made of, for example, a nonmagnetic resin material.

  As shown in FIG. 1, a stator 16 is fixed to the inner peripheral surface of the yoke housing 13. The stator 16 includes a stator core 17 having a plurality of teeth 17 a extending radially inward, and a winding 20 wound around the teeth 17 a of the stator core 17 via an insulator 19. The stator 16 generates a rotating magnetic field when a drive current is supplied from the external control circuit S to the winding 20.

As shown in FIG. 2, the stator core 17 has a total of 12 teeth 17a. Therefore, the number of slots 17b formed between the teeth 17a is also twelve.
As shown in FIG. 2, the teeth 17 a include a winding part 18 a and projecting parts 18 b that protrude from the radially inner end of the winding part 18 a to both sides in the circumferential direction. In the winding portion 18a, the U-phase, V-phase, and W-phase windings 20 are wound in concentrated winding.

  As shown in FIG. 1, the rotor 21 of the brushless motor 11 has a rotating shaft 22 and is disposed inside the stator 16. The rotating shaft 22 is a non-magnetic metal shaft, and is rotatably supported by bearings 23 and 24 supported by the bottom 13 a of the yoke housing 13 and the end plate 14.

  As shown in FIGS. 3 and 4, the rotor 21 includes first and second rotor cores 31 and 32 that are fixed to the rotating shaft 22 while the axial distance between the rotating shafts 22 is maintained by press-fitting the rotating shaft 22. And an annular magnet 33 as a field magnet interposed between the first rotor core 31 and the second rotor core 32 in the axial direction. Further, the rotor 21 includes back auxiliary magnets 34 and 35 and interpole magnets 36 and 37.

  As shown in FIGS. 3A and 4, the first rotor core 31 has a plurality of (five in the present embodiment) first claws on the outer periphery of the substantially disk-shaped first core base 31 a. The magnetic pole 31b protrudes radially outward and extends in the axial direction. Specifically, the first claw-shaped magnetic pole 31b includes a protrusion 31c that protrudes radially outward from the outer periphery of the first core base 31a, and a claw 31d that is provided at the tip of the protrusion 31c and extends in the axial direction. . The protrusion 31c is formed in a fan shape when viewed from the axial direction. The claw portion 31d has a fan-shaped cross section in the direction perpendicular to the axis. The first core base 31a of the first rotor core 31 has an insertion hole 31e through which the rotary shaft 22 is inserted at the approximate center thereof.

  As shown in FIGS. 3B and 4, the second rotor core 32 has the same shape as the first rotor core 31, and a plurality of the second rotor cores 32 are arranged at equal intervals on the outer periphery of the substantially disk-shaped second core base 32 a. The second claw-shaped magnetic pole 32b protrudes radially outward and extends in the axial direction. Specifically, the second claw-shaped magnetic pole 32b has a protrusion 32c that protrudes radially outward from the outer periphery of the second core base 32a, and a claw 32d that is provided at the tip of the protrusion 32c and extends in the axial direction. . The protrusion 32 c is formed in a fan shape when viewed from the axial direction, similarly to the protrusion 31 c of the first rotor core 31. The claw portion 32d has a fan-shaped cross section in the direction perpendicular to the axis. The second core base 32a of the second rotor core 32 has an insertion hole 32e through which the rotary shaft 22 is inserted at the approximate center thereof.

  In the first and second rotor cores 31 and 32, the rotary shaft 22 is press-fitted into the insertion holes 31e and 32e, and the first and second core bases 31a and 32a are on the outer side (opposite sides) in the axial direction. It is press-fitted and fixed to the rotary shaft 22 so that the distance becomes a predetermined constant distance. At this time, the second rotor core 32 is arranged such that each of the second claw-shaped magnetic poles 32b is disposed between the first claw-shaped magnetic poles 31b adjacent in the circumferential direction, and the first core base 31a and the second core base 32a. The annular magnet 33 is assembled to the first rotor core 31 so as to be disposed (clamped) between the first rotor core 31 and the second rotor core 31.

  As shown in FIG. 4, the annular magnet 33 is a magnet such as a ferrite magnet or a neodymium magnet, and is formed in an annular shape having a central hole 33 a through which the rotary shaft 22 is inserted. The annular magnet 33 causes the first claw-shaped magnetic pole 31b to function as a first magnetic pole (N pole in the present embodiment), and causes the second claw-shaped magnetic pole 32b to function as a second magnetic pole (S pole in the present embodiment). Thus, it is magnetized in the axial direction. That is, the rotor 21 of the present embodiment is a so-called Landell type rotor using an annular magnet 33 as a field magnet.

  As shown in FIG. 2, the rotor 21 has four first claw-shaped magnetic poles 31b that are N poles and four second claw-shaped magnetic poles 32b that are S poles arranged alternately in the circumferential direction. The number is 8 poles (the number of pole pairs is 4). That is, in the present embodiment, the number of poles of the rotor 21 is set to “8”, and the number of teeth 17a of the stator 16 is set to “12”. That is, the number of poles of the rotor 21 is 2n (where n is a natural number, 4 in the present embodiment), the number of slots 17b (slot number) is 3n, and the ratio of the number of poles to the number of slots is 2: 3. It is configured as follows.

  Further, as shown in FIGS. 3B and 4, there is a back surface auxiliary between the back surface 31f (radially inner surface) of each first claw-shaped magnetic pole 31b and the outer peripheral surface 32g of the second core base 32a. A magnet 34 is arranged. The back auxiliary magnet 34 has a substantially fan-shaped cross section in the direction orthogonal to the axis, and the second core base 32a has a side that abuts on the back surface 31f of the first claw-shaped magnetic pole 31b as the N pole having the same polarity as the first claw-shaped magnetic pole 31b. Is magnetized so that the side in contact with the outer peripheral surface 32g becomes the S pole having the same polarity as the second core base 32a.

  Further, as shown in FIGS. 3A and 4, between the back surface 32f of each second claw-shaped magnetic pole 32b and the outer peripheral surface 31g of the first core base 31a, similarly to the first claw-shaped magnetic pole 31b. The back auxiliary magnet 35 is disposed. The back auxiliary magnet 35 has a fan-shaped cross section in the direction perpendicular to the axis, and is magnetized so that the side in contact with the back surface 32f is an S pole and the side in contact with the outer peripheral surface 31g of the first core base 31a is an N pole. . As the back auxiliary magnets 34 and 35, for example, ferrite magnets can be used.

As shown in FIGS. 2 and 3A and 3B, interpole magnets 36 and 37 are disposed between the circumferential directions of the first claw-shaped magnetic pole 31b and the second claw-shaped magnetic pole 32b.
In the rotor 21 configured as described above, the outer diameter of the assembly 21a assembled with the first rotor core 31, the second rotor core 32, and the annular magnet 33 is Do, the inner diameter is Di, and the length in the axial direction (thickness). ) Is preferably Hr, the following relationship is preferably satisfied. That is, the assembly 21a has a range of 0 <Di / Do <0.56 (provided that 0.2 ≦ Hr / Do ≦ 0.3), or 0.06 <Hr / Do <0.96 (provided that It is preferable to satisfy the range of 0 <Di / Do ≦ 0.2). Furthermore, the assembly 21a has a range of 0 <Di / Do ≦ 0.4 (provided that 0.2 ≦ Hr / Do ≦ 0.3), or 0.1 ≦ Hr / Do <0.65 (provided that It is more preferable to satisfy a range of 0 <Di / Do ≦ 0.2). Furthermore, the assembly 21a has a range of 0 <Di / Do ≦ 0.1 (provided that 0.2 ≦ Hr / Do ≦ 0.3), or 0.2 ≦ Hr / Do <0.3 (provided that It is preferable to satisfy the range of 0 <Di / Do ≦ 0.2).

  In FIG. 4, the assembly 21a is illustrated such that Di / Do = 0.2 and Hr / Do = 0.3. Incidentally, the outer diameter Do of the assembly 21a is the same as the diameter of a virtual circle passing through the outermost peripheral portions of the claw-shaped magnetic poles 31b and 32b of the first and second rotor cores 31 and 32, and the inner diameter Di of the assembly 21a is The diameters of the insertion holes 31e and 32e of the first and second rotor cores 31 and 32 are the same. Furthermore, the length (thickness) in the axial direction of the assembly 21a is the same as the axial length of the claw-shaped magnetic poles 31b and 32b of the first and second rotor cores 31 and 32.

  As shown in FIG. 1, the rotor 21 is provided with a sensor magnet 42 via a substantially disc-shaped magnet fixing member 41. Specifically, the magnet fixing member 41 includes a disc portion 41b having a boss portion 41a formed at the center, and a cylinder portion 41c extending in a cylindrical shape from the outer edge of the disc portion 41b. An annular sensor magnet 42 is fixed so as to come into contact with the peripheral surface and the surface of the disc portion 41b. The magnet fixing member 41 is fixed on the side close to the first rotor core 31 with the boss portion 41 a fitted on the rotary shaft 22.

  In the end plate 14, a Hall IC 43 as a magnetic sensor is provided at a position facing the sensor magnet 42 in the axial direction. When the Hall IC 43 senses the N-pole and S-pole magnetic fields based on the sensor magnet 42, it outputs an H level detection signal and an L level detection signal to the control circuit S, respectively.

Next, the operation of the brushless motor 11 configured as described above will be described.
When a three-phase driving current is supplied from the control circuit S to the winding 20, a rotating magnetic field is generated in the stator 16, and the rotor 21 is driven to rotate. At this time, as the sensor magnet 42 facing the Hall IC 43 rotates, the level of the detection signal output from the Hall IC 43 is switched according to the rotation angle (position) of the rotor 21, and the control circuit S is based on the detection signal. To the winding 20 is supplied with a three-phase drive current that switches at an optimal timing. As a result, a rotating magnetic field is generated satisfactorily, and the rotor 21 is driven to rotate continuously.

  The assembly 21a constituting the rotor 21 of the present embodiment has a range of 0 <Di / Do <0.56 (where 0.2 ≦ Hr / Do ≦ 0.3), or 0.06 <Hr / Do. <0.96 (where 0 <Di / Do ≦ 0.2) is satisfied. Furthermore, the assembly 21a has a range of 0 <Di / Do ≦ 0.4 (provided that 0.2 ≦ Hr / Do ≦ 0.3), or 0.1 ≦ Hr / Do <0.65 (provided that 0 <Di / Do ≦ 0.2). Furthermore, the assembly 21a has a range of 0 <Di / Do ≦ 0.1 (provided that 0.2 ≦ Hr / Do ≦ 0.3), or 0.2 ≦ Hr / Do <0.3 (provided that 0 <Di / Do ≦ 0.2).

(Configuration of comparative example)
Here, as a comparative example of the motor 11 of this embodiment, as shown in FIG. 7, an SPM (Surface Permanent Magnet) type rotor 103 in which permanent magnets 101 a and 101 b are provided on the surface of the rotor core 102, and the diameter of the rotor 103 A motor 100 including a stator 104 provided on the outer side in the direction will be described. FIG. 7 is a partial cross-sectional perspective view of the motor 100, and the rotor 103 and the stator 104 are approximately half of the whole.

  As shown in FIG. 7, the rotor 103 of the motor 100 of the comparative example has a permanent magnet 101a having a radially outer magnetic pole on the radially outer surface of the rotor core 102 and an S magnetic pole on the radially outer side. Magnets 101b are alternately arranged in the circumferential direction. The rotor 103 of the comparative example is provided with four permanent magnets 101a and 101b (only two are shown in FIG. 7), and the same number as the rotor 21 of the embodiment is a total of eight (only four in FIG. 7). (Shown).

  As shown in FIG. 7, the stator 104 of the motor 100 of the comparative example is provided on the radially outer side of the rotor 103 so as to face the rotor 103 in the radial direction. The stator 104 of the comparative example has a total of twelve slots 105 (only seven are shown in FIG. 7), which is the same number as the stator 16 of the embodiment.

(Comparison between the motor of the embodiment and the motor of the comparative example)
Next, changes in output in the motor 11 of the embodiment (hereinafter referred to as the Landell motor) and the motor 100 of the comparative example (conventional motor) will be mainly described with reference to FIGS. In FIG. 5, the ratio between the torque of the Landel motor and the torque of the conventional motor is shown on the vertical axis, and Hr / Do is shown on the horizontal axis. Incidentally, FIG. 5 is a graph in the case of Di / Do = 0.2. In FIG. 6, as in FIG. 5, the ratio between the torque of the Landel motor and the torque of the conventional motor is shown on the vertical axis, and Di / Do is shown on the horizontal axis. Incidentally, FIG. 6 is a graph in the case of Hr / Do = 0.3.

  As can be seen from FIG. 5, by setting the range of 0.06 <Hr / Do <0.96 (where 0 <Di / Do ≦ 0.2), higher torque than that of the conventional motor can be obtained. Further, by setting the range 0.1 ≦ Hr / Do <0.65 (where 0 <Di / Do ≦ 0.2), a torque higher by 20% or more can be obtained. Furthermore, by setting the range of 0.2 ≦ Hr / Do <0.3 (where 0 <Di / Do ≦ 0.2), a torque higher by 35% or more than that of the conventional motor can be obtained.

  Further, as can be seen from FIG. 6, by setting the range of 0 <Di / Do <0.56 (where 0.2 ≦ Hr / Do ≦ 0.3), a torque higher than that of the conventional motor can be obtained. Furthermore, by setting the range 0 <Di / Do ≦ 0.4 (however, 0.2 ≦ Hr / Do ≦ 0.3), a torque higher by 20% or more than that of the conventional motor can be obtained. Furthermore, by setting the range of 0 <Di / Do ≦ 0.1 (where 0.2 ≦ Hr / Do ≦ 0.3), it is possible to obtain a torque that is 40% or more higher than that of the conventional motor.

As described above, as shown in FIG. 4, by setting Di / Do = 0.2 and Hr / Do = 0.3, it is possible to obtain a torque 30% or more higher than that of the conventional motor. It becomes.
Next, the effect of this embodiment will be described.

  (1) The assembly 21a of the rotor 21 has a range of 0 <Di / Do <0.56 (where 0.2 ≦ Hr / Do ≦ 0.3), or 0.06 <Hr / Do <0. By setting 96 (however, 0 <Di / Do ≦ 0.2), a higher torque than that of the conventional motor can be obtained.

  (2) The assembly 21a of the rotor 21 has a range of 0 <Di / Do ≦ 0.4 (where 0.2 ≦ Hr / Do ≦ 0.3) or 0.1 ≦ Hr / Do <0. By satisfying the range of 65 (where 0 <Di / Do ≦ 0.2), a higher torque than that of the conventional motor can be obtained.

  (3) The assembly 21a of the rotor 21 has a range of 0 <Di / Do ≦ 0.1 (where 0.2 ≦ Hr / Do ≦ 0.3) or 0.2 ≦ Hr / Do <0. Torque higher than that of the conventional motor satisfying the range of 3 (where 0 <Di / Do ≦ 0.2) can be obtained.

In addition, you may change the said embodiment as follows.
In the above embodiment, the interpole magnets 36 and 37 are provided, but a configuration that is omitted may be employed.

In the above-described embodiment, the back auxiliary magnets 34 and 35 are provided.
-In the said embodiment, although the winding method of the coil | winding 20 was concentrated winding, it is not restricted to this.

In the above embodiment, the number of poles of the rotor 21 is 8 and the number of slots (the number of teeth) of the stator 16 is 12. However, these may be changed as appropriate.
-You may combine the said embodiment and said each modification suitably.

  DESCRIPTION OF SYMBOLS 11 ... Motor, 21 ... Rotor, 21a ... Assembly | attachment, 31 ... 1st rotor core, 31b, 32b ... Claw-shaped magnetic pole, 32 ... 2nd rotor core, 33 ... Ring magnet as field magnet, Di ... Inner diameter, Do ... Outer diameter, Hr ... length.

Claims (4)

A plurality of claw-shaped magnetic poles project radially outward and extend in the axial direction on the outer periphery of each substantially disk-shaped core base, and the claw-shaped magnetic poles are formed with the core bases facing each other. First and second rotor cores arranged alternately in the circumferential direction;
The claw-shaped magnetic poles of the first rotor core function as the first magnetic poles by being arranged between the axial directions of the core bases and magnetized in the axial direction, and the claw-shaped magnetic poles of the second rotor core are made to function as the first magnetic poles. A field magnet that functions as a second magnetic pole;
A rotor with
When the outer diameter of the assembly in which the first rotor core, the second rotor core, and the field magnet are assembled is Do, the inner diameter is Di, and the length in the axial direction is Hr,
The range is 0 <Di / Do <0.56 (where 0.2 ≦ Hr / Do ≦ 0.3), or 0.06 <Hr / Do <0.96 (where 0 <Di / Do ≦ 0. A rotor configured to satisfy the range of 2). The rotor according to claim 1, wherein
The assembly has a range of 0 <Di / Do ≦ 0.4 (where 0.2 ≦ Hr / Do ≦ 0.3), or 0.1 ≦ Hr / Do <0.65 (where 0 < A rotor configured to satisfy a range of Di / Do ≦ 0.2). The rotor according to claim 1 or 2,
The assembly has a range of 0 <Di / Do ≦ 0.1 (where 0.2 ≦ Hr / Do ≦ 0.3), or 0.2 ≦ Hr / Do <0.3 (where 0 < A rotor configured to satisfy a range of Di / Do ≦ 0.2).   The motor provided with the rotor as described in any one of Claims 1-3.