WO2018037652A1

WO2018037652A1 - Consequent pole-type rotor, electric motor, and air conditioner

Info

Publication number: WO2018037652A1
Application number: PCT/JP2017/020020
Authority: WO
Inventors: 優人浦邊; 及川　智明; 山本　峰雄; 石井　博幸; 洋樹麻生; 隼一郎尾屋; 諒伍 ▲高▼橋
Original assignee: 三菱電機株式会社
Priority date: 2016-08-22
Filing date: 2017-05-30
Publication date: 2018-03-01
Also published as: WO2018037455A1; JPWO2018037652A1; CN208835850U; JP6545393B2

Abstract

A consequent pole-type rotor (20) comprises: a rotor core (5) having first magnetic pole sections (60) and second magnetic pole sections (61), said first magnetic pole sections (60) having a plurality of permanent magnets and having a first polarity as a result of the permanent magnets and said second magnetic pole sections (61) being formed between adjacent permanent magnets and having a second polarity being a different polarity from the first polarity; and an annular magnet (72) provided in one end section (5a) in the axial direction of the rotor core (5). The annular magnet (72) comprises: a plurality of position detection magnets (70) arranged in the rotational direction of the rotor core (5) and being for detecting the position of the first magnetic pole sections (60) and the second magnetic pole sections (61) of the rotor core (5); and a plurality of coupling sections (71) that are provided between adjacent position detection magnets and couple adjacent position detection magnets (70) to each other. In the plurality of position detection magnets (70), the polarity of the magnetic pole for an end surface on the opposite side to the rotor core (5) in the axial direction is the same as the second polarity.

Description

Consecutive pole type rotor, electric motor and air conditioner

The present invention relates to a continuous pole type rotor, an electric motor, and an air conditioner.

Conventionally, in order to improve the energy saving performance of an air conditioner, a rare earth magnet having a high energy density such as a neodymium sintered magnet is generally used as a permanent magnet of an electric motor mounted on a compressor of an air conditioner. An electric motor using a neodymium sintered magnet has been developed for an air conditioner fan.

Such a permanent magnet is expensive because it contains a valuable rare earth element. Therefore, there is a strong demand for reducing the cost by reducing the amount of permanent magnet used and the processing cost.

Permanent magnets are generally processed into a specified shape by cutting block-like chunks. For this reason, the processing cost increases as the number of permanent magnets used in the electric motor increases.

As a method for reducing the number of permanent magnets used in an electric motor, there is a method in which a rotor is constituted by a so-called continuous pole. In the continuous pole type rotor, magnet magnetic poles formed by permanent magnets and salient poles formed on the core material without using permanent magnets are alternately arranged in the circumferential direction. Therefore, the number of magnet magnetic poles and the number of salient poles are both half the number of poles. Also, half the number of magnetic poles has the same polarity, and half the number of salient poles has a different polarity from the magnetic pole. As described above, in the continuous pole type rotor, the number of permanent magnets is half of the normal number. However, in the continuous pole type rotor, there is a problem that the inductance differs between the magnetic pole and the salient pole, and vibration and noise increase due to the imbalance of the inductance.

In response to this problem, the continuous pole type rotor disclosed in Patent Document 1 improves the asymmetry of the inductance by reducing the shape of the flux barrier at both ends of the permanent magnet, thereby reducing vibration and noise. ing. An electric motor using a continuous pole type rotor disclosed in Patent Document 1 includes a magnetic sensor that detects a position of the rotor in the rotation direction, and the magnetic sensor leaks in the axial direction from the magnet magnetic pole of the rotor. The rotation control of the rotor is performed by alternately detecting the first magnetic field and the second magnetic field leaking in the axial direction from the salient poles of the rotor.

JP 2012-244783 A

However, in the continuous pole type rotor disclosed in Patent Document 1, since the magnetic flux leaking in the axial direction from the magnet magnetic pole is larger than the magnetic flux leaking in the axial direction from the salient pole, the first magnetic field detected by the magnetic sensor. There is a possibility that the imbalance between the first magnetic field and the second magnetic field increases, and the rotational position detection accuracy decreases.

The present invention has been made in view of the above, and an object of the present invention is to obtain a continuous pole type rotor capable of improving the detection accuracy of the rotational position.

In order to solve the above-described problems and achieve the object, a continuous pole type rotor according to the present invention has a plurality of permanent magnets, and a first magnetic pole portion having a first polarity by the permanent magnets, A rotor core having a second magnetic pole portion having a second polarity different from the first polarity formed between adjacent permanent magnets, and an annular magnet provided at one end of the rotor core in the axial direction A plurality of position detecting magnets arranged in the rotation direction of the rotor core and for detecting the positions of the first magnetic pole portion and the second magnetic pole portion of the rotor core; A plurality of connecting portions that are provided between adjacent position detecting magnets and connect adjacent position detecting magnets to each other, and the plurality of position detecting magnets are arranged in the rotor core in the axial direction of the rotor core. The polarity of the magnetic pole on the opposite end face is the same as the second polarity.

The continuous pole type rotor according to the present invention has an effect of improving the detection accuracy of the rotational position.

Sectional drawing of the electric motor provided with the consequent pole type rotor which concerns on Embodiment 1 of this invention Sectional view of the mold stator shown in FIG. Sectional drawing which shows the state by which the rotor was inserted in the mold stator shown in FIG. Configuration diagram of a stator core composed of a plurality of divided core portions and developed in a band shape The figure which shows the state which bent the expand | deployed stator core shown in FIG. 4, and comprised it cyclically | annularly Sectional view of the rotor shown in FIG. 1 is a perspective view of a continuum pole type rotor according to a first embodiment of the present invention. Front view of the rotor shown in FIG. The perspective view of the annular magnet shown in FIG. The figure which shows the 1st modification of the continuum pole type rotor which concerns on Embodiment 1 of this invention. Front view of the rotor shown in FIG. The perspective view of the annular magnet shown in FIG. The figure which shows the 2nd modification of the continuum pole type rotor which concerns on Embodiment 1 of this invention. Front view of the rotor shown in FIG. First perspective view of the annular magnet shown in FIG. Second perspective view of the annular magnet shown in FIG. The figure which shows an example of a structure of the air conditioner which concerns on Embodiment 2 of this invention.

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, a continuous pole type rotor, an electric motor, and an air conditioner according to an embodiment of the present invention will be described in detail based on the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view of an electric motor including a continuous pole type rotor according to Embodiment 1 of the present invention. An electric motor 100 shown in FIG. 1 includes a mold stator 10, a rotor 20, and a metal bracket 30 attached to one end portion in the axial direction of the mold stator 10. The “axial direction” is equal to the stacking direction of the plurality of rotor cores constituting the rotor 20. The electric motor 100 is a brushless DC motor having a permanent magnet in the rotor 20 and driven by an inverter. The rotor 20 is an internal magnet type and a continuous pole type.

The mold stator 10 includes a stator 40 and a mold resin 50 that covers the stator 40, and the axial direction of the mold stator 10 coincides with the axial direction of the shaft 23 that penetrates the rotor 20. In FIG. 1, the stator core 41, which is a constituent element of the stator 40, the coil 42 wound around the stator core 41, the insulating portion 43 provided on the stator core 41, and the insulating portion 43 are provided. The neutral point terminal 44b is shown. In FIG. 1, the board 45 attached to the insulating portion 43, which is a component of the stator 40, the lead wire lead part 46 assembled to the board 45, and the lead wire 47 lead out from the lead wire lead part 46. In addition, an IC (Integrated Circuit) 49a mounted on the substrate 45 and a Hall IC 49b which is a magnetic sensor mounted on the surface of the substrate 45 on the rotor 20 side are shown.

The rotor 20 is mounted on the shaft 23, the resin portion 24 that integrates the main body of the rotor 20 and the shaft assembly 27, and the load-side rolling attached to the shaft 23 and supported by the bearing support portion 11 of the mold stator 10. A bearing 21a and an anti-load-side rolling bearing 21b attached to the shaft 23 and supported by the bracket 30 are provided. The load side 110 represents the end surface side from which the shaft 23 projects out of both end surfaces of the electric motor 100, and the anti-load side 120 represents the end surface side on which the bracket 30 is provided.

The rotor 20 is installed at one end portion 5a of the rotor core 5 in the axial direction, and a plurality of position detection magnets 70 for detecting the position of the rotor core 5 in the rotation direction, each of which is a position detection magnet. And a plurality of connecting portions 71 for connecting 70 together. The Hall IC 49b alternately detects a magnetic field generated in the axial direction from the position detection magnet 70 and a magnetic field generated in the axial direction from a first magnetic pole portion described later, and has a pulse shape corresponding to the detected change in the magnetic field. Output a signal. The IC 49a calculates the position of the rotor 20 in the rotation direction based on the signal output from the Hall IC 49b and controls the rotation of the rotor 20. Detailed configurations of the position detection magnet 70 and the connecting portion 71 will be described later. In the present embodiment, the Hall IC 49b is used as the position detection means for detecting the position of the rotor core 5 in the rotation direction. However, the position detection means is not limited to the Hall IC 49b. An element that alternately detects a magnetic field generated in the axial direction and a magnetic field generated in the axial direction from the first magnetic pole portion may be used.

The shaft assembly 27 includes an insulating sleeve 26 including a pair of insulating sleeves 26-1 and 26-2, and the insulating sleeve 26 is disposed between the anti-load side rolling bearing 21 b and the shaft 23.

FIG. 2 is a cross-sectional view of the mold stator shown in FIG. In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals. The mold stator 10 has an opening 10b at one end in the axial direction of the mold stator 10, and the rotor 20 is inserted into the opening 10b. A hole 11a larger than the diameter of the shaft assembly 27 of the rotor 20 shown in FIG. 1 is formed at the axial end of the mold stator 10 into which the load-side rolling bearing 21a of the rotor 20 inserted into the opening 10b is fitted. Opened.

FIG. 3 is a cross-sectional view showing a state where a rotor is inserted into the mold stator shown in FIG. 3, the same components as those in FIG. 1 are denoted by the same reference numerals. The rotor 20 inserted from the opening 10b of the mold stator 10 shown in FIG. 2 is arranged so that the load side of the shaft assembly 27 passes through the hole 11a shown in FIG. The At this time, the load-side rolling bearing 21 a attached to the shaft 23 is pushed in until it contacts the bearing support portion 11 shown in FIG. 1 and is supported by the bearing support portion 11. The bearing support portion 11 is an axial end portion of the mold stator 10 and is provided on the opposite side of the opening portion 10b.

The anti-load-side rolling bearing 21b is attached to the anti-load side of the shaft assembly 27. The attachment of the anti-load side rolling bearing 21b is generally performed by press fitting. Although details will be described later, an insulating sleeve 26 formed integrally with the shaft 23 is provided between the anti-load side rolling bearing 21b and the anti-load side of the shaft 23.

The bracket 30 shown in FIG. 1 closes the opening 10b of the mold stator 10 shown in FIG. 2 and supports the anti-load-side rolling bearing 21b shown in FIG. 3, and is press-fitted into the mold stator 10. . The bracket 30 includes a bearing support portion 30a and a press-fit portion 30b formed integrally with the bearing support portion 30a. The bearing support portion 30a supports the anti-load side rolling bearing 21b. The press-fit portion 30b has a ring shape.

The bracket 30 is attached to the mold stator 10 by press-fitting the press-fit portion 30b into the opening 10b side of the inner peripheral portion 10a of the mold stator 10. The outer diameter of the press-fit portion 30b is larger than the inner diameter of the inner peripheral portion 10a of the mold stator 10 by the press-fit allowance. Examples of the material of the bracket 30 include a galvanized steel plate, an aluminum alloy, an austenitic stainless alloy, a copper alloy, cast iron, steel, or an iron alloy.

The configuration of the mold stator 10 will be described below. The mold stator 10 shown in FIG. 2 includes a stator 40 and a mold resin 50 for molding. An unsaturated polyester resin is used for the mold resin 50. In particular, a bulk clay thermosetting resin (BMC) obtained by adding various additives to an unsaturated polyester resin is desirable for an electric motor. Thermoplastic resins such as polybutylene terephthalate (PBT) and polyphenylene sulfide (PPS) also have a good aspect because they can recycle the runner during molding.

However, the unsaturated polyester resin and BMC have a linear expansion coefficient close to that of ferrous materials such as the stator core 41, the load side rolling bearing 21a, and the anti-load side rolling bearing 21b, and the thermal shrinkage rate is 1 of the thermoplastic resin. / 10 or less is excellent for obtaining dimensional accuracy.

Also, compared with the case where the outer shell of the electric motor 100 is formed of a metal such as iron and aluminum, the heat dissipation is excellent when the outer shell of the electric motor 100 is formed of unsaturated polyester resin and BMC. Further, when the outer shell of the electric motor 100 is formed of metal, the metal forming the outer shell of the electric motor 100 is separated from the coil 42 and the substrate 45 due to an insulating problem. On the other hand, since unsaturated polyester resin and BMC are insulators, there is no problem of insulation even when the coil 42 and the substrate 45 are covered, and since heat conductivity is high, the heat dissipation is excellent, and the high output of the electric motor 100 Contribute to

The load side rolling bearing 21 a is supported by the bearing support portion 11 formed of the mold resin 50, and the anti-load side rolling bearing 21 b and the bracket 30 are supported by the inner peripheral portion 10 a formed of the mold resin 50. For this reason, when the dimensional accuracy of the mold resin 50 is poor, the axis of the rotor 20 and the axis of the stator 40 are deviated to cause vibration and noise. However, by using an unsaturated polyester resin and BMC having a small heat shrinkage rate, it becomes easy to ensure dimensional accuracy after molding.

In addition, when a resin having a large linear expansion coefficient is used, when the motor 100 becomes high temperature, there is a case where the rattling of the bearing becomes a problem. Unsaturated polyester resin and BMC have linear expansion coefficients that are close to the linear expansion coefficients of ferrous materials such as the stator core 41, the load-side rolling bearing 21a, and the anti-load-side rolling bearing 21b. Deviation between the axis of the child 20 and the axis of the stator 40 can be suppressed.

Further, since the unsaturated polyester resin and BMC restrain the stator 40 when cured, the deformation of the stator 40 due to the excitation force of the electric motor 100 can be suppressed, and vibration and noise can be suppressed.

FIG. 4 is a configuration diagram of a stator core configured by a plurality of divided core portions and developed in a band shape. The stator core 41 shown in FIG. 4 is obtained by arranging a plurality of divided core portions 400 such that each of the plurality of divided core portions 400 is in contact with another adjacent one of the plurality of divided core portions 400. . Each of the plurality of divided core portions 400 includes a back yoke 401 and teeth 402 protruding from the back yoke 401. Between adjacent back yokes 401, a thin portion 403 that connects the back yokes 401 is provided.

FIG. 5 is a diagram showing a state in which the developed stator core shown in FIG. 4 is bent and configured in an annular shape. The annular stator core 41 shown in FIG. 5 is formed into an annular shape by folding the belt-shaped divided core portion 400 group at the thin portion 403 after the coils 42 of FIG. 1 are applied to each of the plurality of teeth 402 shown in FIG. Formed.

4 and 5, the stator core 41 composed of a plurality of divided core portions 400 can be wound with the coil 42 in a state of being developed in a band shape, so that the density of the coil 42 can be increased and high efficiency can be achieved. It is effective for conversion. However, since the split core portion 400 is connected by the thin wall portion 403, the rigidity of the stator core 41 when it is formed in an annular shape is low, and those having a large excitation force such as the continuous pole type electric motor 100 are not suitable. It is effective to mold the stator core 41 with a saturated polyester resin, that is, to cover the stator core 41 with an unsaturated polyester resin.

In addition, the stator core 41 composed of a plurality of divided core portions 400 has a concavity and convexity at the end of the back yoke 401 in addition to the structure in which the back yokes 401 adjacent to each other are connected by a thin portion 403 as shown in FIG. The structure may be such that a dowel is formed and the dowels are connected to each other, or a plurality of back yokes 401 separated from each other may be fixed together by welding or fitting. By covering the stator core 41 configured in this manner with an unsaturated polyester resin, vibration and noise can be reduced.

In this way, it is desirable to completely cover the stator core 41 with the unsaturated polyester resin. However, as shown in FIG. 2, from the outer peripheral portion 41-1 of the stator core 41 to the outer peripheral portion 10-1 of the unsaturated polyester resin. When the thickness is T1 and the thickness from the inner peripheral portion 41-2 of the stator core 41 to the inner peripheral portion 10-2 of the unsaturated polyester resin is T2, the mold stator 10 satisfies the relationship of T1> T2. It is desirable to be configured.

If the thickness T2 is increased too much, the diameter of the rotor 20 must be reduced, the magnetic gap between the stator core 41 and the rotor 20 will be increased, and the motor characteristics will be degraded. Therefore, in the mold stator 10 according to Embodiment 1, the rigidity of the radially outer thickness T1 is increased by making the thickness T1 larger than the thickness T2. “Radial direction” indicates the radial direction of the rotor 20.

In addition, since the axial center of the rotor 20 and the axial center of the stator 40 shift | deviate and the imbalance arises in the clearance gap between the stator core 41 and the rotor 20, the excitation force by eccentricity will be superimposed, Eccentricity must be assembled as small as possible. As the thickness T2 increases, unbalance is likely to occur in the gap, and it is also effective to make the thickness T2 zero. However, in that case, the gap between adjacent teeth 402 of the stator core 41 is effective. Fill the space with the unsaturated polyester resin up to the tip of the teeth. As the excitation force, there is also a force that swings the tip of the teeth to the left and right, and completely filling the space between the teeth 402 leads to suppressing the influence of this force.

Further, in the case of the stator core 41 shown in FIGS. 4 and 5, the influence of the excitation force acting on the teeth 402 can be suppressed by providing the unsaturated polyester resin on the divided surface 404 between the adjacent divided core portions 400.

Therefore, in the stator core 41, a hole 405 is formed in the split surface 404 of the annular stator core 41 shown in FIG. The hole 405 is formed by providing a groove or notch between adjacent back yokes 401. When the unsaturated polyester is molded into the annular stator core 41, the holes 405 are filled with the unsaturated polyester resin. The hole 405 does not need to be filled with unsaturated polyester in the entire region from one end surface to the other end surface in the axial direction of the stator core 41, and is slightly filled from one end surface in the axial direction of the stator core 41. Even in this case, the effect of damping the vibration can be expected. As the hole 405 is increased in order to increase the filling amount, the magnetic properties are deteriorated, so that the filling amount is appropriately determined. The hole 405 of the dividing surface 404 can obtain the same effect even if it has a groove shape that opens to the outer peripheral surface of the stator core 41 or a groove shape that opens to the slot 406 side.

Next, the configuration of the rotor 20 shown in FIG. 1 will be described.

FIG. 6 is a cross-sectional view of the rotor shown in FIG. The rotor 20 has an annular rotor core 5 and five magnet insertion holes 2 arranged in the circumferential direction. “Circumferential direction” indicates the circumferential direction of the rotor 20. The number of magnet insertion holes 2 is half the number of poles of the rotor 20. The five magnet insertion holes 2 are arranged at equal intervals in the circumferential direction. The five magnet insertion holes 2 are arranged at an equal distance from the rotation shaft 6. The rotating shaft 6 coincides with the axis of the rotor core 5. The five magnet insertion holes 2 penetrate the rotor core 5 in the axial direction. The magnet insertion hole 2 is formed near the outer peripheral surface of the rotor core 5 and extends in the circumferential direction. Adjacent magnet insertion holes 2 are spaced apart. The rotor core 5 has a shaft insertion hole 7 at the center.

The rotor core 5 is composed of a core material that is a soft magnetic material, and specifically, a plurality of electromagnetic steel plates are laminated. The thickness of one electromagnetic steel sheet is generally 0.1 mm to 0.7 mm.

The five permanent magnets 1 are inserted into the five magnet insertion holes 2, respectively. The permanent magnet 1 has a flat plate shape with a rectangular cross section. An example of the plate thickness of the permanent magnet 1 is 2 mm. The permanent magnet 1 is a rare earth magnet and is a neodymium sintered magnet mainly composed of Nd (neodymium) -Fe (iron) -B (boron).

The magnet insertion hole 2 is composed of a rectangular first region 3A into which the permanent magnet 1 is inserted and two second regions 3B into which the permanent magnet 1 is not inserted. The second region 3B is a first region 3B. One region is formed at each end in the longitudinal direction of the region 3A. The second region 3B has a function of a flux barrier that suppresses the leakage magnetic flux a with respect to the permanent magnet 1 inserted in the first region 3A, and the magnetic flux density distribution on the outer peripheral surface of the rotor core 5 is determined. It has a function of short-circuiting the magnetic flux of the permanent magnet 1 inserted in the adjacent magnet insertion hole 2 through the rotor core 5 close to a sine wave.

The rotor 20 has ten magnetic poles arranged on the outer peripheral surface of the rotor core 5 so that the polarities are alternately arranged in the circumferential direction. Specifically, the rotor 20 is formed by five first magnetic poles each formed by five permanent magnets 1 and having the same polarity, and a rotor core 5 between the permanent magnets 1 adjacent to each other. It has five second magnetic poles having different polarities from the first magnetic poles. In the illustrated example, the first magnetic pole is an N pole and the second magnetic pole is an S pole, but may be reversed. The ten magnetic poles of the rotor 20 are arranged at equiangular intervals in the circumferential direction with a pole pitch of 360 degrees / 10 = 36 degrees.

Thus, in the continuous pole type rotor 20, the five permanent magnets 1, which are half the number of poles, each provide five first magnetic poles. Further, each of the five second magnetic poles having half the number of poles is formed on the core material of the rotor core 5 between the permanent magnets 1 adjacent to each other. The second magnetic pole is a so-called salient pole and is formed by magnetizing the rotor 20.

Therefore, the rotor 20 includes the first magnetic pole portion 60 having the first polarity by the permanent magnet 1 including the permanent magnet 1 and the second magnetic pole that is a core magnetic pole portion not including the permanent magnet 1 and is a virtual pole. The second magnetic pole portions 61 are arranged alternately in the circumferential direction of the rotor 20. In the continuous pole type rotor 20, the number of poles is an even number of 4 or more.

The outer shape of the rotor core 5 is a so-called flower circle shape. The flower-circle shape is a shape in which the outer diameter of the rotor core 5 is maximum at the pole centers 62 and 63 and is minimum at the gap 64, and the arc from the pole centers 62 and 63 to the gap 64 is an arc shape. It is. The pole center 62 is the pole center of the first magnetic pole, and the pole center 63 is the pole center of the second magnetic pole. In the illustrated example, the flower circle shape is a shape in which ten petals of the same shape and the same size are arranged at an equal angle. Therefore, the outer diameter of the rotor core 5 at the pole center 62 is equal to the outer diameter of the rotor core 5 at the pole center 63. The circumferential width of the magnet insertion hole 2 is wider than the pole pitch.

FIG. 7 is a perspective view of a continuum pole type rotor according to the first embodiment of the present invention. FIG. 8 is a front view of the rotor shown in FIG. FIG. 9 is a perspective view of the annular magnet shown in FIG. The rotor 20 is provided at one end portion 5a of the rotor core 5 in the axial direction, and includes a plurality of position detection magnets 70 for detecting the position of the rotor core 5 in the rotation direction. Between the adjacent position detection magnets 70, a plurality of connecting portions 71 are provided, each connecting the position detection magnets 70 to each other. An annular magnet 72 is formed by alternately connecting the position detection magnet 70 and the connecting portion 71.

Each of the plurality of position detection magnets 70 has the same polarity as the second polarity of the second magnetic pole part 61 in the polarity of the one end face 70b1 in the axial direction, and the rotation of the second magnetic pole part 61. It is installed at the same phase as the phase in the direction. Specifically, the position detection magnet 70 includes two end faces 70b1 and 70b2 in the axial direction. The end surface 70b1 is an end surface on the opposite side of the rotor core 5 of the position detection magnet 70. The polarity of the end face 70b1 is the S pole. The end surface 70b2 is an end surface of the position detection magnet 70 on the rotor core 5 side. The polarity of the end face 70b2 is the N pole. The magnetic flux direction of the position detecting magnet 70 is the axial direction as shown in FIG. The second magnetic pole portion 61 has a radially outer polarity of S poles and a radially inner polarity of N poles. The south pole of the second magnetic pole portion 61 corresponds to the second polarity described above. As shown in FIG. 7, the arrow from the north pole to the south pole of the second magnetic pole portion 61 indicates the magnetic flux direction of the second magnetic pole portion 61. Of the magnetic flux of the second magnetic pole portion 61, the magnetic flux leaking in the axial direction is assisted by the magnetic flux leaking in the axial direction from the position detection magnet 70, and is detected by the Hall IC 49b described above. The first magnetic pole portion 60 has a radially outer polarity of N poles and a radially inner polarity of S poles. The north pole of the first magnetic pole portion 60 corresponds to the first polarity described above. As shown in FIG. 7, the arrow from the north pole to the south pole of the first magnetic pole portion 60 indicates the magnetic flux direction of the first magnetic pole portion 60. An example of the material of each of the plurality of position detection magnets 70 is a bond magnet. By using the bond magnet, the degree of freedom of processing of the position detection magnet 70 is increased compared to the case of using a sintered magnet. Therefore, the number of processing steps in manufacturing the position detection magnet 70 is reduced, and the position detection magnet is reduced. The manufacturing cost of 70 can be reduced.

Each of the plurality of connecting portions 71 may be made of the same material as the mold resin 50, or may be made of a magnet having the same polarity as the first polarity of the first magnetic pole portion 60. By constructing the plurality of connecting portions 71 with the same material as the mold resin 50, the manufacturing cost of the rotor 20 can be reduced as compared with the case of constituting with a magnet.

The thickness of the connecting portion 71 in the axial direction is T3, the thickness of the position detecting magnet 70 in the axial direction is T4, the thickness of the connecting portion 71 in the radial direction is T5, and the thickness of the position detecting magnet 70 in the radial direction is T6. , The rotor 20 is configured such that the relationship of T4> T3 and T6> T5 is satisfied.

In the continuous pole type rotor 20, the magnetic flux leaking in the axial direction from the first magnetic pole portion 60 is larger than the magnetic flux leaking in the axial direction from the second magnetic pole portion 61. Therefore, the first magnetic field detected by the Hall IC 49b due to the magnetic flux leaking in the axial direction from the first magnetic pole portion 60 and the second magnetic field detected by the Hall IC 49b by the magnetic flux leaking from the second magnetic pole portion 61 in the axial direction. There is a possibility that the detection accuracy of the rotational position is lowered.

As described above, the rotor 20 according to the first embodiment includes the plurality of permanent magnets 1, and the first magnetic pole portion 60 having the first polarity by the permanent magnet 1 and the adjacent permanent magnet 1. A rotor core 5 having a plurality of second magnetic pole portions 61 having a second polarity different from the formed first polarity, and provided at one end of the rotor core 5 in the axial direction of the rotor core 5. The annular magnet 72 is arranged in the rotational direction of the rotor core 5 and detects the positions of the first magnetic pole portion 60 and the second magnetic pole portion 61 of the rotor core 5. A plurality of position detecting magnets 70 and a plurality of connecting portions 71 provided between the adjacent position detecting magnets 70 and connecting the adjacent position detecting magnets 70 to each other. In the plurality of position detecting magnets 70 and the plurality of connecting portions 71, the polarity of the magnetic poles of the end surface 70b1 opposite to the rotor core 5 in the axial direction of the rotor core 5 is the same as the second polarity. With this configuration, since the magnetic flux leaking in the axial direction from the second magnetic pole portion 61 is assisted by the magnetic flux generated from the position detection magnet 70, the second magnetic field detected by the Hall IC 49b is generated by the position detection magnet 70. It is a large value compared to the case without it. Thereby, the imbalance between the first magnetic field and the second magnetic field is reduced. In the first embodiment, the polarity of the end face 70b1 of the position detection magnet 70 may be the same as the second polarity, and is not limited to the S pole. That is, when the second polarity of the second magnetic pole portion 61 is N-pole, the polarity of the end face 70b1 of the position detection magnet 70 is N-pole.

Since the phases in the rotation direction of the first magnetic pole portion 60 and the position detection magnet 70 detected by the Hall IC 49b are the same, the motor 100 shown in FIG. 1 has a magnetic flux leaking in the axial direction from the first magnetic pole portion 60. By using the magnetic flux leaking in the axial direction from the position detection magnet 70, the position of the rotor 20 can be detected with high accuracy.

Since the rotor 20 according to the first embodiment uses the number of position detection magnets 70 corresponding to half the total number of magnetic poles, the number of position detection magnets 70 corresponding to the total number of magnetic poles is used. Thus, an increase in the manufacturing cost of the rotor 20 can be suppressed while improving the position detection accuracy.

In addition, since the electric motor 100 according to the first embodiment uses the annular magnet 72, the assembly time of the rotor 20 is longer than when the plurality of position detection magnets 70 are individually manufactured and assembled to the rotor core 5. Can be shortened. Further, by using the annular magnet 72, it is possible to reduce the risk that the position detecting magnet 70 is detached when the rotor 20 is assembled and the yield is lowered, and the position detecting magnet 70 is detached during the operation of the electric motor 100. The risk of splashing within 100 can be reduced. Therefore, the electric motor 100 according to Embodiment 1 can improve the position detection accuracy while suppressing an increase in manufacturing cost of the electric motor 100 and suppressing a decrease in quality.

In addition, the following method can be illustrated as an installation method of the annular magnet 72 to the rotor core 5.
(1) By providing a rib-like member (not shown) between the shaft 23 and the position detecting magnet 70 and providing a rib-like member (not shown) between the shaft 23 and the connecting portion 71, the rotor core 5 A circular magnet 72 is installed.
(2) A plurality of unillustrated pedestals arranged in the circumferential direction are provided at one end portion 5a of the rotor core 5 in the axial direction, and an annular magnet 72 is installed in the pedestal group.

Hereinafter, a modified example of the rotor 20 according to the first embodiment will be described.

FIG. 10 is a diagram showing a first modification of the consequent pole type rotor according to the first embodiment of the present invention. FIG. 11 is a front view of the rotor shown in FIG. 12 is a perspective view of the annular magnet shown in FIG.

The difference between the rotor 20A shown in FIGS. 10, 11 and 12 and the rotor 20 shown in FIG. 7 is that the thickness of the connecting portion 71 in the radial direction is different. The rotor 20A is configured such that the relationship of T4> T3 and T5 = T6 is satisfied. Since the connecting portion 71 does not need a function of assisting magnetic flux leaking in the axial direction from the first magnetic pole portion 60, the thickness T3 and T5 of the connecting portion 71 is thinner than the thickness T4 and T6 of the position detection magnet 70. can do. Therefore, compared with the case where the thicknesses T3 and T5 of the connecting portion 71 are the same as the thicknesses T4 and T6 of the position detection magnet 70, the manufacturing cost of the annular magnet 72 can be reduced without reducing the position detection accuracy. The thicknesses T3 and T5 of the connecting portion 71 are set in consideration of the strength that can prevent the

rotors

20 and 20A from being damaged during manufacture and can prevent the motor 100 shown in FIG. 1 from being damaged during operation.

FIG. 13 is a view showing a second modification of the consequent pole type rotor according to the first embodiment of the present invention. FIG. 14 is a front view of the rotor shown in FIG. FIG. 15 is a first perspective view of the annular magnet shown in FIG. 16 is a second perspective view of the annular magnet shown in FIG.

The difference between the rotor 20B shown in FIGS. 13, 14 and 15 and the rotor 20 shown in FIG. 7 is that the annular magnet 72 of the rotor 20B has a plurality of protrusions 73 extending from the annular magnet 72 in the axial direction. Is provided.

As shown in FIGS. 15 and 16, each of the plurality of protrusions 73 is disposed near both end faces 70 a in the circumferential direction of the position detection magnet 70, and the other end face of the position detection magnet 70 in the axial direction. The shape extends in the axial direction from the 70b2 side. More specifically, pedestals 74 are provided on both end faces 70 a in the circumferential direction of the position detection magnet 70. The pedestal 74 is installed on the other end face 70b2 of the position detecting magnet 70 in the axial direction. The protrusion 73 is installed on the pedestal 74 and is formed so as to extend on the opposite side of the pedestal 74 from the position detecting magnet 70 in the axial direction. The protrusion 73 and the pedestal 74 are manufactured by integral molding with the annular magnet 72.

13 and 14, each of the plurality of protrusions 73 is inserted into the second region 3 </ b> B constituting the magnet insertion hole 2. At this time, when the pedestal 74 is in contact with the one end portion 5a of the rotor core 5, each of the plurality of protrusions 73 is positioned in the axial direction.

In electric motor 100 according to the present embodiment, the rotational position detection accuracy can be improved by matching the phases of first magnetic pole portion 60 and position detection magnet 70 detected by Hall IC 49b in the rotational direction. . In the rotor 20B shown in FIGS. 13 to 16, the plurality of protrusions 73 inserted into the second region 3B function as positioning protrusions for the annular magnet 72 in the rotation direction. Therefore, in the rotor 20 </ b> B, when the annular magnet 72 is assembled, a shift between the phase in the rotation direction of the position detection magnet 70 and the phase in the rotation direction of the second magnetic pole portion 61 can be suppressed. Therefore, the electric motor 100 using the rotor 20B can improve the detection accuracy of the rotational position compared to the electric motor 100 using the rotor 20 or the rotor 20A.

Further, the rotor 20B can be manufactured by integrally forming the protrusion 73 and the pedestal 74 with the annular magnet 72, so that the position detecting magnet 70 and an axial positioning member (not shown) are individually manufactured to form the rotor core 5. Compared to the assembly, the assembly time of the rotor 20 can be shortened, and the number of manufactured parts can be reduced. Therefore, the yield is improved, and the increase in the manufacturing cost of the rotor 20B can be suppressed.

Embodiment 2. FIG.
FIG. 17 is a diagram illustrating an example of a configuration of an air conditioner according to Embodiment 2 of the present invention. The air conditioner 300 includes an indoor unit 310 and an outdoor unit 320 connected to the indoor unit 310. An indoor unit blower (not shown) is mounted on the indoor unit 310, and an outdoor unit blower 330 is mounted on the outdoor unit 320. In addition, a compressor 340 is mounted on the outdoor unit 320. The electric motor 100 according to Embodiment 1 is used for the indoor unit blower, the outdoor unit blower 330, and the compressor 340.

Thus, by using the electric motor 100 according to the first embodiment as a drive source for the indoor unit blower, the outdoor unit blower 330, and the compressor 340, the accuracy of the rotational position is improved, and the motor efficiency is improved. And the air conditioner 300 which can suppress manufacturing cost can be obtained.

The electric motor 100 according to the first embodiment can be mounted on an electric device other than the air conditioner 300, and in this case, the same effect as that of the present embodiment can be obtained.

The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

1 permanent magnet, 2 magnet insertion hole, 3A first region, 3B second region, 5 rotor core, 5a one end, 6 rotation shaft, 7 shaft insertion hole, 10 mold stator, 10-1, 41- 1 outer periphery, 10-2, 10a, 41-2 inner periphery, 10b opening, 11, 30a bearing support, 11a, 405 holes, 20, 20A, 20B rotor, 21a load side rolling bearing, 21b anti-load Side rolling bearing, 23 shaft, 24 resin part, 26, 26-1 insulation sleeve, 27 shaft assembly, 30 bracket, 30b press-fit part, 40 stator, 41 stator core, 42 coil, 43 insulation part, 44b neutral point Terminal, 45 substrate, 46 lead wire lead part, 47 lead wire, 49b Hall IC, 50 mold resin, 60 1st magnetic pole Minute, 61 second magnetic pole part, 62, 63 pole center, 61a, 61b, 70a, 70b1, 70b2, end face, 64 poles, 70 position detecting magnet, 71 connecting part, 72 annular magnet, 73 protrusion, 74 pedestal , 100 motor, 110 load side, 120 anti-load side, 300 air conditioner, 310 indoor unit, 320 outdoor unit, 330 outdoor unit blower, 340 compressor, 400 split core section, 401 back yoke, 402 teeth, 403 thin wall Part, 404 division surface, 406 slots.

Claims

A first magnetic pole portion having a plurality of permanent magnets and having a first polarity by the permanent magnet, and a second magnetic pole having a second polarity different from the first polarity formed between the adjacent permanent magnets A rotor core having a portion;
An annular magnet provided at one end of the rotor core in the axial direction;
With
The annular magnet is
A plurality of position detection magnets arranged in the rotation direction of the rotor core and for detecting positions of the first magnetic pole portion and the second magnetic pole portion of the rotor core;
A plurality of connecting portions provided between the adjacent position detecting magnets and connecting the adjacent position detecting magnets;
With
The plurality of position detecting magnets are:
A continuum pole type rotor in which the polarity of the magnetic pole on the end surface opposite to the rotor core in the axial direction of the rotor core is the same as the second polarity.
2. The continuous pole type magnet according to claim 1, wherein the plurality of position detection magnets are arranged at positions where a phase in a rotation direction of the rotor core coincides with a phase in the rotation direction of the second magnetic pole portion. Rotor.
3. The continuous pole type rotor according to claim 1, wherein the plurality of position detecting magnets are connected to each other by a connecting portion having a thickness smaller than that of the position detecting magnet.
The rotor core includes a plurality of magnet insertion holes into which the permanent magnets are inserted,
The plurality of position detection magnets include protrusions for positioning the position detection magnets,
The continuous pole type according to any one of claims 1 to 3, wherein the protrusion is inserted into a region between the permanent magnet inserted into the magnet insertion hole and the magnet insertion hole. Rotor.
The continuum pole type rotor according to claim 4, wherein a pedestal in contact with one end of the rotor core is provided between the position detecting magnet and the protrusion.
The continuous pole type rotor according to any one of claims 3 to 5, wherein a thickness of the position detecting magnet is larger than a thickness of the connecting portion.
The continuous pole type rotor according to any one of claims 1 to 6, wherein the position detection magnet is formed of a bond magnet.
An electric motor comprising the consequent pole type rotor and stator according to any one of claims 1 to 7.
An air conditioner equipped with the electric motor according to claim 8.