Motors, compressors, and equipment

Abstract

Provided is an electric motor 14 in which a stator-side small hole 80 is formed in a stator tooth tip 32B, a pair of stator tooth base side surfaces forming a stator tooth base 32A is set as a front stator tooth base side surface 32AF located in the rotation direction of a rotor 20 and a rear stator tooth base side surface 32AR located in the counter-rotation direction of the rotor 20, the stator-side small hole 80 is arranged within a width of 1 / 3T from the rear stator tooth base side surface 32AR, where T is the width of the stator tooth base 32A in the circumferential direction, a front flux barrier 60F is made longer than a rear flux barrier 60R, a rotor-side front small hole 70F is formed at the rear end of the front flux barrier 60F, and a rotor-side rear small hole 70R is formed at the front end of the rear flux barrier 60R, whereby high efficiency can be maintained and electromagnetic force in the radial direction and torque ripple, which is torque unevenness in the rotation direction, can be suppressed at the same time. Also provided are a compressor 10 using the electric motor 14, and equipment using the compressor 10.

Description

[Technical field]

[0001] The present invention relates to an electric motor, a compressor using this electric motor, and equipment using this compressor. [Background technology]

[0002] Patent Document 1 proposes an electric motor in which the rotor is provided with a magnetic saturation promoting means to make it easier to saturate, thereby reducing the unbalanced magnetic attraction force generated between the rotor and stator, thereby suppressing axial runout of the shaft and enabling the compression mechanism to be driven appropriately. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-162379 A Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, a magnetic resistance section is placed on the rotational direction side of the rotor to reduce the unbalanced magnetic attraction force, which is a radial electromagnetic force, and suppress the axial vibration of the shaft, thereby enabling the compression mechanism to be driven appropriately. However, this tends to increase torque ripple, which is an uneven rotation of the motor.

[0005] Therefore, an object of the present invention is to provide an electric motor that can maintain high efficiency and simultaneously suppress radial electromagnetic force and torque ripple, which is torque unevenness in the rotational direction, a compressor using this electric motor, and equipment using this compressor. [Means for solving the problem]

[0006] The electric motor 14 of the present invention described in claim 1 has a rotor 20 in which a plurality of permanent magnets 22 are arranged around a rotating shaft 4, and a stator 30 arranged with an air gap between the rotor 20, the stator 30 has an annular stator yoke 31 centered around the rotating shaft 4, a plurality of stator teeth 32 extending from the stator yoke 31 toward the rotor 20, and slots 33 formed between the stator teeth 32, a winding is arranged in the slot 33, and the stator The permanent magnet 22 has a stator tooth base 32A around which the winding is wound, and a stator tooth tip 32B that forms a stator tooth inner circumferential surface 32S that faces the rotor 20. The rotor 20 has flux barriers 60 that extend from both ends of the permanent magnet 22 toward the magnetic pole center of the permanent magnet 22. The flux barriers 60 are formed along a rotor outer circumferential surface 20S of the rotor 20 and are disposed on the stator 30 side relative to the permanent magnet 22. a front flux barrier 60F formed in the rotation direction of the rotor 20 and a rear flux barrier 60R formed in the counter-rotation direction of the rotor 20, and a stator side small hole 80 is formed in the stator teeth tip portion 32B, and a pair of stator teeth base side surfaces forming the stator teeth base portion 32A are arranged as a front stator teeth base side surface 32AF located in the rotation direction of the rotor 20 and a rear stator teeth base side surface 32AF located in the counter-rotation direction of the rotor 20. a rear stator teeth base side surface 32AR located at a position corresponding to the rear stator teeth base 32A; a circumferential width of the stator teeth base 32A being T; the stator side small holes 80 being disposed within a range of width 1 / 3T from the rear stator teeth base side surface 32AR; the front flux barrier 60F being longer than the rear flux barrier 60R; a rotor side front small hole 70F being formed at a rear end of the front flux barrier 60F; and a rotor side rear small hole 70R being formed at a front end of the rear flux barrier 60R. The front flux barrier 60F is formed within a range of an angle α with respect to the center of the rotating shaft 4, and when the number of poles of the rotor 20 is P, the angle α is set within a range of 4≦α≦120 / P with respect to the center between the poles. It is characterized by the fact that Claim 2 The present invention described above is characterized in that, in the electric motor 14 described in claim 1, the stator side small hole 80, the rotor side front small hole 70F, and the rotor side rear small hole 70R are gaps. Claim 3The present invention described above is characterized in that, in the electric motor 14 described in claim 1, the stator side small hole 80, the rotor side front small hole 70F, and the rotor side rear small hole 70R are circular. Claim 4 The present invention described above is characterized in that, in the electric motor 14 described in claim 1, the dimension L from the stator tooth inner surface 32S of the stator tooth tip portion 32B to the stator side small hole 80 is made smaller than the diameter of the stator side small hole 80. Claim 5 The present invention is characterized in that, in the electric motor 14 described in claim 1, the dimension M from the rotor outer peripheral surface 20S to the rotor side front small hole 70F is smaller than the diameter of the rotor side front small hole 70F. Claim 6 The present invention is characterized in that, in the electric motor 14 described in claim 1, the dimension N from the rotor outer peripheral surface 20S to the rotor side rear small hole 70R is smaller than the diameter of the rotor side rear small hole 70R. Claim 7 The present invention described above is characterized in that, in the electric motor 14 described in claim 1, a dimension Q from the rotor outer circumferential surface 20S to the flux barrier 60 is made smaller than the radial width of the flux barrier 60. Claim 8 The present invention is characterized in that, in the electric motor 14 described in claim 1, there is one stator side small hole 80, and there are two rotor side front small holes 70F and two rotor side rear small holes 70R. Claim 9 The compressor 10 of the invention as described above has the following features: Claim 8 The compressor 10 uses the electric motor 14 described above, and is characterized in that a compression mechanism portion 13 is connected to the rotating shaft 4, and the refrigerant is compressed by the compression mechanism portion 13. Claim 10 The device of the present invention described is Claim 9 The device uses the compressor 10 described above, and is characterized in that the compressor 10, a condenser 17, a pressure reducing device 18, and an evaporator 19 are connected in a ring shape by piping. Effect of the Invention

[0007] According to the present invention, it is possible to simultaneously suppress radial electromagnetic force and torque ripple, which is torque unevenness in the rotational direction, while maintaining high efficiency. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing the configuration of a compressor using an electric motor according to an embodiment of the present invention, and a refrigeration device using the compressor. [Diagram 2] A diagram showing the main components of an electric motor according to the present embodiment. [Diagram 3] FIG. 1 is an explanatory diagram showing the effect of the electric motor of the present invention. [Figure 4] Magnetic flux density contour diagram of the present invention and the comparative example [Diagram 5] Graph showing magnetic flux density in the gap when the electromagnetic force is maximum in the present invention and a comparative example [Figure 6] A configuration diagram of a scroll compressor using the electric motor according to the present embodiment, and a refrigeration system using this scroll compressor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In an electric motor according to a first embodiment of the present invention, stator side small holes are formed at the tips of the stator teeth, a pair of stator teeth base side surfaces forming the stator teeth base are a front stator teeth base side surface located in the direction of rotor rotation and a rear stator teeth base side surface located in the opposite direction of rotor rotation, the stator side small holes are arranged within a range of width 1 / 3T from the rear stator teeth base side surface, where T is the circumferential width of the stator teeth base, the front flux barrier is made longer than the rear flux barrier, a rotor side front small hole is formed at the rear end of the front flux barrier, and a rotor side rear small hole is formed at the front end of the rear flux barrier. The front flux barrier is formed within an angle α range with respect to the center of the rotating shaft. If the number of poles of the rotor is P, the angle α is set within the range of 4≦α≦120 / P with the center between the poles as the reference. According to this embodiment, it is possible to simultaneously suppress electromagnetic force in the radial direction and torque ripple, which is torque unevenness in the rotational direction, while maintaining high efficiency. In addition, a flux barrier suitable for the number of poles of the rotor can be formed.

[0010] The present invention SecondIn this embodiment, the stator side small hole, the rotor side front small hole, and the rotor side rear small hole in the electric motor according to the first embodiment are made to be gaps. According to this embodiment, productivity is excellent.

[0011] The present invention Third In this embodiment, the stator side small hole, the rotor side front small hole, and the rotor side rear small hole in the electric motor according to the first embodiment are circular. According to this embodiment, productivity is excellent.

[0012] The present invention Fourth In this embodiment, in the electric motor according to the first embodiment, the dimension L from the inner peripheral surface of the stator tooth at the tip of the stator tooth to the small hole on the stator side is made smaller than the diameter of the small hole on the stator side. According to this embodiment, it is possible to enhance the effect of reducing the magnetic flux density in the air gap between the rotor and the stator.

[0013] The present invention Fifth In the second embodiment, the dimension M from the rotor outer circumferential surface to the rotor front small hole in the electric motor according to the first embodiment is made smaller than the diameter of the rotor front small hole. According to this embodiment, it is possible to enhance the effect of reducing the magnetic flux density in the air gap between the rotor and the stator.

[0014] The present invention Sixth In the second embodiment, the dimension N from the rotor outer circumferential surface to the rotor side rear small hole in the electric motor according to the first embodiment is made smaller than the diameter of the rotor side rear small hole. According to this embodiment, it is possible to enhance the effect of reducing the magnetic flux density in the air gap between the rotor and the stator.

[0015] The present invention Seventh In this embodiment, the dimension Q from the outer circumferential surface of the rotor to the flux barrier is set smaller than the radial width of the flux barrier in the electric motor according to the first embodiment. According to this embodiment, it is possible to enhance the effect of reducing the magnetic flux density in the air gap between the rotor and the stator.

[0016] The present invention Eighth In this embodiment, the motor according to the first embodiment has one small hole on the stator side and two small holes on the front and rear sides of the rotor side. According to this embodiment, the fluctuation range of the electromagnetic force in the radial direction can be reduced, and the torque ripple can be significantly reduced.

[0017] The present invention 9th The compressor according to the embodiment includes first to fourth Eighth The present invention relates to a compressor using an electric motor according to any one of the above embodiments, and a compressor mechanism is connected to the rotating shaft, and the refrigerant is compressed by the compressor mechanism. According to this embodiment, a compressor with low vibration can be realized.

[0018] The present invention 10th The device according to the embodiment of the present invention comprises: 9th The compressor, the condenser, the pressure reducing device, and the evaporator are connected in a circular manner by piping. According to the present embodiment, it is possible to realize a highly efficient device with low noise due to low vibration without reducing torque. EXAMPLES

[0019] A compressor according to an embodiment of the present invention will be described below, however, the present invention is not limited to the following embodiment.

[0020] 1 is a configuration diagram of a compressor using an electric motor according to the present embodiment, and a refrigeration system using this compressor. The compressor according to the present embodiment is a rotary compressor. A suction pipe 2 for drawing in a refrigerant and a discharge pipe 3 for discharging the refrigerant are connected to the sealed container 1. A compression mechanism 13 for compressing the refrigerant drawn through the suction pipe 2 and an electric motor 14 for driving the compression mechanism 13 are arranged inside the sealed container 1. The bottom of the sealed container 1 serves as an oil reservoir 11. The compression mechanism 13 is composed of a cylinder 13a, a piston 13b, a vane (not shown), a main bearing 13c, and an auxiliary bearing 13d. The cylinder 13a is fixed to the sealed container 1. The piston 13b is rotatably fitted to an eccentric portion 4a of a rotating shaft 4 that passes through the cylinder 13a. The vane reciprocates in the vane groove following the piston 13b that rolls along the inner wall surface of the cylinder 13a. The main bearing 13c and the auxiliary bearing 13d seal the upper and lower end surfaces of the cylinder 13a and support the rotating shaft 4. The electric motor 14 is made up of a stator 30 fixed to the sealed container 1 and a rotor 20 arranged on the inner periphery of the stator 30 . The refrigerant is sucked into the compression mechanism 13 through the suction pipe 2, and is compressed in the compression mechanism 13. Thereafter, the refrigerant passes through the electric motor 14 and is discharged from the discharge pipe 3.

[0021] In the refrigeration system according to this embodiment, a compressor 10, a condenser 17, a pressure reducing device 18, and an evaporator 19 are connected in a ring shape by piping. The condenser 17 condenses the refrigerant discharged from the discharge pipe 3, the pressure reducing device 18 reduces the pressure of the refrigerant condensed in the condenser 17, and the evaporator 19 evaporates the refrigerant reduced in pressure by the pressure reducing device 18. The refrigerant evaporated in the evaporator 19 is returned to the compressor 10 via the accumulator 16. 1, only one end (lower end) of the rotating shaft 4 is supported by bearings (main bearing 13c, sub-bearing 13d), so axial runout is likely to occur at the other end (upper end) of the rotating shaft 4. Therefore, the electric motor 14, which can simultaneously suppress radial electromagnetic force and torque ripple, which is torque unevenness in the rotational direction, is highly effective in reducing vibration.

[0022] FIG. 2 is a diagram showing the main components of an electric motor according to this embodiment, where FIG. 2(a) is a diagram showing the stator and rotor, FIG. 2(b) is a diagram showing the rotor, and FIG. 2(c) is an enlarged view of the main components of FIG. 2(a). In this embodiment, the rotor 20 is fixed to the rotating shaft 4, and the stator 30 is fixed to the sealed container 1. In addition, in this embodiment, the electric motor 14 has a pole number P of six. The arrow shown in FIG. 2(a) indicates the direction of rotation of the rotor 20, and in this embodiment, the rotor 20 rotates counterclockwise.

[0023] The rotor 20 has a rotor core 21 formed in a cylindrical shape by laminating rotor core sheets, and permanent magnets 22 arranged in slits formed on the outer periphery of the rotor core 21. The rotor 20 has a plurality of permanent magnets 22 arranged around the rotating shaft 4. The rotor core sheet is an electromagnetic steel sheet having a thickness of about 0.3 mm, and the rotor core 21 is made of a magnetic material. The rotor core 21 has a through hole 23 in the center in which the rotating shaft 4 is disposed, and is provided with a plurality of rotor refrigerant passages 24 in the axial direction around the through hole 23. The rotor refrigerant passages 24 are formed concentrically between the through hole 23 and the permanent magnets 22.

[0024] The rotor 20 has flux barriers 60 that extend at a predetermined width from both ends of the permanent magnets 22 toward the magnetic pole center of the permanent magnets 22. The flux barriers 60 are magnetic resistance parts formed by gaps that continue from the slits in which the permanent magnets 22 are arranged. The flux barriers 60 increase the magnetic resistance, and are highly effective if they are non-magnetic, and may be filled with resin. The flux barrier 60 is formed in an arc shape along the rotor outer circumferential surface 20S of the rotor 20, and is disposed on the stator side of the permanent magnets 22. The flux barrier 60 includes a front flux barrier 60F formed in the rotation direction of the rotor 20, and a rear flux barrier 60R formed in the counter rotation direction of the rotor 20.

[0025] The front flux barrier 60F is formed within an angle α range with respect to the center of the pole gap relative to the center of the rotating shaft 4, and the rear flux barrier 60R is formed within an angle β range with respect to the center of the pole gap relative to the center of the rotating shaft 4. Here, the angle α is greater than the angle β. That is, the front flux barrier 60F is formed to be longer than the rear flux barrier 60R. The angle α forming the front flux barrier 60F is in the range of 4≦α≦120 / P with respect to the center between the poles, where P is the number of poles of the rotor 20. By making the dimension Q from the rotor outer peripheral surface 20S to the flux barrier 60 smaller than the radial width of the flux barrier 60, the effect of reducing the magnetic flux density in the air gap between the rotor 20 and the stator 30 can be enhanced.

[0026] A rotor-side front small hole 70F is formed at the rear end of the front flux barrier 60F, and a rotor-side rear small hole 70R is formed at the front end of the rear flux barrier 60R. It is preferable that there are two rotor-side front small holes 70F and two rotor-side rear small holes 70R. The rotor-side front small holes 70F and the rotor-side rear small holes 70R are for increasing magnetic resistance, and are highly effective if they are non-magnetic. Although they may be filled with resin, it is preferable that they are voids. In this way, by making the rotor-side front small holes 70F and the rotor-side rear small holes 70R voids, excellent productivity is achieved.

[0027] By making the dimension M from the rotor outer surface 20S to the rotor side front small hole 70F smaller than the diameter of the rotor side front small hole 70F, the effect of reducing the magnetic flux density in the air gap between the rotor 20 and the stator 30 can be enhanced. In addition, by making the dimension N from the rotor outer surface 20S to the rotor side rear small hole 70R smaller than the diameter of the rotor side rear small hole 70R, the effect of reducing the magnetic flux density in the air gap between the rotor 20 and the stator 30 can be enhanced. It is preferable that the dimension Q from the rotor outer peripheral surface 20S to the flux barrier 60, the dimension M from the rotor outer peripheral surface 20S to the rotor side front small hole 70F, and the dimension N from the rotor outer peripheral surface 20S to the rotor side rear small hole 70R are the same.

[0028] The stator 30 is disposed with an air gap between it and the rotor 20. The stator 30 is configured by laminating stator core sheets in the axial direction of the rotating shaft 4. The stator core sheets are electromagnetic steel sheets with a thickness of about 0.3 mm, and the stator 30 is configured of a magnetic material. The stator 30 has an annular stator yoke 31 centered on the rotating shaft 4 of the rotor 20, a plurality of stator teeth 32 extending from the stator yoke 31 toward the rotor 20, and slots 33 formed between the stator teeth 32. A winding (not shown) is arranged in the slots 33. In this embodiment, the stator 30 is formed by dividing the stator into a plurality of stator segments, each corresponding to a stator tooth 32, and arranging the divided stator segments in an annular shape.

[0029] Stator teeth 32 have stator teeth base portions 32A around which windings (not shown) are wound with insulating material (not shown) interposed therebetween, and stator teeth tip portions 32B formed at the tips of stator teeth base portions 32A. Stator tooth tip portions 32B form stator tooth inner peripheral surface 32S that faces rotor outer peripheral surface 20S of rotor 20. Stator tooth tip portions 32B are formed to protrude on both sides beyond circumferential width T of stator tooth base portion 32A. Stator tooth inner peripheral tapered surfaces 32Sa are formed on both sides of this protruding stator tooth inner peripheral surface 32S, with the air gap gradually expanding toward the ends.

[0030] A single stator side small hole 80 is formed in the stator tooth tip portion 32B. The stator side small hole 80 is intended to increase magnetic resistance, and is most effective if it is non-magnetic. Although the small hole 80 may be filled with resin, it is preferable that the small hole 80 is a gap. By making the small hole 80 a gap in this way, productivity is excellent. If a pair of stator teeth base side surfaces forming the stator teeth base 32A are the front stator teeth base side surface 32AF located in the rotation direction of the rotor 20 and the rear stator teeth base side surface 32AR located in the opposite rotation direction of the rotor 20, the stator side small hole 80 is arranged within a range of width 1 / 3T from the rear stator teeth base side surface 32AR. More preferably, the stator side small hole 80 is within a range of width 1 / 4T from the rear stator teeth base side surface 32AR. In addition, the stator side small hole 80 is arranged along the stator teeth inner peripheral surface 32S that forms a certain air gap, rather than the stator teeth inner peripheral tapered surface 32Sa. The distance between the front stator teeth base side surface 32AF and the rear stator teeth base side surface 32AR is the circumferential width T of the stator teeth base 32A.

[0031] By making the dimension L from the stator tooth inner surface 32S of the stator tooth tip portion 32B to the stator side small hole 80 smaller than the diameter of the stator side small hole 80, the effect of reducing the magnetic flux density in the air gap between the rotor 20 and the stator 30 can be enhanced. Furthermore, it is preferable that the dimension L from the stator tooth inner surface 32S to the stator side small hole 80 is the same as the dimension Q from the rotor outer surface 20S to the flux barrier 60, the dimension M from the rotor outer surface 20S to the rotor side front small hole 70F, and the dimension N from the rotor outer surface 20S to the rotor side rear small hole 70R. Moreover, it is preferable that the diameter of the stator side small hole 80 is the same as the diameter of the rotor side front small hole 70F and the diameter of the rotor side rear small hole 70R. In this embodiment, the stator side small hole 80, the rotor side front small hole 70F, and the rotor side rear small hole 70R are circular, but may be elliptical or polygonal.

[0032] FIG. 3 is an explanatory diagram showing the effect of the electric motor of the present invention. The electric motor 14 of the present invention is the electric motor 14 described with reference to FIG. 2, and as a comparative example, the electric motor 14 shown in FIG. 3(c) is used. In the motor shown in Fig. 3(c), the stator side small hole 80 and the rotor side rear small hole 70R are not formed. Also, in the motor 14 shown in Fig. 3(c), the front flux barrier 60F has the same length as the rear flux barrier 60R. The motor 14 shown in Fig. 3(c) has the same configuration as the motor 14 shown in Fig. 2 in other respects. FIG. 3(a) shows the electromagnetic force acting as a radial force, and the present invention is able to reduce the amplitude value by 7.6% compared to the comparative example. FIG. 3(b) shows torque fluctuation, and the present invention is able to reduce torque ripple by 50% compared to the comparative example. Moreover, the motor 14 according to the present invention maintained the same efficiency as the comparative example.

[0033] FIG. 4 is a contour diagram of magnetic flux density in the present invention and a comparative example. 4(a) shows the stator shown in FIG. 2, FIG. 4(b) shows the rotor shown in FIG. 2, FIG. 4(c) shows the stator shown in FIG. 3(c), and FIG. 4(d) shows the rotor shown in FIG. 3(c). Figure 4 shows the magnetic flux density when the electromagnetic forces acting as radial forces are equal, and it can be seen that there are influences due to the front flux barrier 60F, the rotor side front small hole 70F, the rotor side rear small hole 70R, and the stator side small hole 80.

[0034] FIG. 5 is a graph showing the magnetic flux density in the gap when the electromagnetic force is maximum in the present invention and a comparative example. As shown in FIG. 5, the present invention can reduce the magnetic flux density in the gap by 2.7% per tooth compared to the comparative example.

[0035] FIG. 6 is a configuration diagram of a scroll compressor using the electric motor according to this embodiment, and a refrigeration system using this scroll compressor. The compressor 10 according to this embodiment includes, in a sealed container 1, a compression mechanism portion 13 for compressing a refrigerant gas, and an electric motor 14 for driving the compression mechanism portion 13. The inside of the sealed container 1 is divided into one container space and the other container space by the compression mechanism part 13. An electric motor 14 is disposed in the other container space. The space inside the other container is divided into a compression mechanism side space and an oil-storage side space by the electric motor 14. And, the oil-storage side space has the oil-storage section 11 disposed therein. A suction pipe 2 and a discharge pipe 3 are fixed to the sealed container 1 by welding. The suction pipe 2 and the discharge pipe 3 lead to the outside of the sealed container 1 and are connected to members that constitute a refrigeration cycle. The suction pipe 2 introduces refrigerant gas from the outside of the sealed container 1, and the discharge pipe 3 discharges the refrigerant gas from one of the spaces inside the container to the outside of the sealed container 1.

[0036] The main bearing member 7a is fixed inside the sealed container 1 by welding, shrink fitting, or the like, and supports the rotating shaft 4. One end of the rotating shaft 4 is supported by the main bearing member 7a, and the other end is supported by a bearing 7b. A fixed scroll 13j is bolted to the main bearing member 7a. An orbiting scroll 13k that meshes with the fixed scroll 13j is sandwiched between the main bearing member 7a and the fixed scroll 13j. The fixed scroll 13j and the orbiting scroll 13k form a scroll-type compression mechanism 13. Between the orbiting scroll 13k and the main bearing member 7a, a rotation restraining mechanism 9 such as an Oldham ring is provided. The rotation restraining mechanism 9 prevents the orbiting scroll 13k from rotating on its axis and guides the orbiting scroll 13k to move in a circular orbit. The orbiting scroll 13k is eccentrically driven by an eccentric portion 4a provided at the upper end of the rotating shaft 4. Due to this eccentric drive, the compression chamber formed between the fixed scroll 13j and the orbiting scroll 13k moves from the outer periphery toward the center of the compression mechanism portion 13, reducing the volume and performing compression.

[0037] The electric motor 14 has a rotor 20 arranged to be rotatable about the rotating shaft 4, and a stator 30 arranged via an air gap with the rotor 20. Note that the configuration of the electric motor 14 is the same as that shown in FIG. 2, and therefore a description thereof will be omitted.

[0038] The refrigerant is sucked into the compression mechanism 13 through the suction pipe 2, and is compressed in the compression mechanism 13. Thereafter, the refrigerant is discharged from the discharge pipe 3. In the refrigeration system according to this embodiment, a compressor 10, a condenser 17, a pressure reducing device 18, and an evaporator 19 are connected in a ring shape by piping. The condenser 17 condenses the refrigerant discharged from the discharge pipe 3, the pressure reducing device 18 reduces the pressure of the refrigerant condensed in the condenser 17, and the evaporator 19 evaporates the refrigerant reduced in pressure by the pressure reducing device 18. The refrigerant evaporated in the evaporator 19 is returned to the compressor 10 through the suction pipe 2 . In the compressor 10 shown in FIG. 6, one end (lower end) of the rotating shaft 4 is supported by a bearing 7b, and the other end (upper end) of the rotating shaft 4 is supported by a main bearing member 7a, so that axial runout is unlikely to occur. However, since vibrations from the electric motor 14 are easily transmitted to the sealed container 1, the effect of reducing vibrations by the electric motor 14, which can simultaneously suppress electromagnetic force in the radial direction and torque ripple, which is torque unevenness in the rotational direction, is high.

[0039] As shown in FIGS. 1 and 6, the electric motor 14 according to this embodiment is suitable for a compressor 10 in which a compression mechanism 13 is connected to a rotary shaft 4 and the compression mechanism 13 compresses a refrigerant. In this embodiment, the vertical compressor 10 has been described, but the horizontal compressor 10 is similarly effective and is suitable for an in-vehicle compressor, for example. Also, although a rotary compressor is shown in Fig. 1 and a scroll compressor is shown in Fig. 6, a reciprocating compressor or other compressors may be used. Low noise is particularly required for vehicle-mounted compressors, so by using the electric motor 14 of this embodiment, which can simultaneously suppress radial electromagnetic force and torque ripple, which is rotational unevenness, the effect of low noise due to low vibration is significant. In addition, in a refrigeration system in which the compressor 10 using the electric motor 14 according to this embodiment is connected in a ring shape with the condenser 17, the pressure reducing device 18, and the evaporator 19 by piping, low noise due to low vibration and high efficiency can be achieved without reducing the torque.

[0040] As described above, the electric motor 14 according to this embodiment has the stator side small holes 80 arranged within a width of 1 / 3T from the base side surface 32AR of the rear stator teeth, the front flux barrier 60F is made longer than the rear flux barrier 60R, the rotor side front small holes 70F are formed at the rear end of the front flux barrier 60F, and the rotor side rear small holes 70R are formed at the front end of the rear flux barrier 60R, thereby maintaining high efficiency and simultaneously suppressing radial electromagnetic force and torque ripple, which is torque unevenness in the rotational direction. In particular, by providing one stator side small hole 80 and two rotor side front small holes 70F and two rotor side rear small holes 70R, the fluctuation range of the radial electromagnetic force can be reduced and torque ripple can be significantly reduced. In this embodiment, the stator 30 divided into a plurality of pieces for each stator tooth 32 is arranged in a circular shape, but the same applies to an integrated stator 30. [Industrial Applicability]

[0041] The compressor of the present invention is useful for devices such as hot water heating systems, indoor air conditioners, vehicle air conditioners, water heaters, refrigerators, showcases, chillers, and freezers. [Explanation of symbols]

[0042] 1. Airtight container 2 Suction pipe 3 Discharge pipe 4 Rotation Axis 4a Eccentric part 7a Main bearing member 7b Bearings 10 Compressor 11 Oil storage section 13 Compression mechanism 13a Cylinder 13b Piston 13c Main bearing 13d Sub bearing 13j Fixed Scroll 13k Swirling Scroll 14 Electric motor 16 Accumulator 17 Condenser 18 Pressure reducing device 19 Evaporator 20 Rotor 20S Rotor outer surface 21 Rotor core 22 Permanent magnets 23 Through hole 24 Rotor refrigerant passage 30 Stator 31 Stator yoke 32 Stator teeth 32A Stator teeth base 32B Stator tooth tip 32AF Front stator teeth base side 32AR Rear stator teeth base side 32S Stator teeth inner surface 32Sa Stator teeth inner circumference tapered surface 33 Slots 60 Flux Barrier 60F Forward Flux Barrier 60R Rear Flux Barrier 70F Rotor side front small hole 70R Rotor side rear small hole 80 Stator side small hole L: Dimension from the inner circumference of the stator teeth to the small hole on the stator side M Dimension from rotor outer periphery to front small hole on rotor side N Dimension from rotor outer periphery to rear small hole on rotor side P Number of poles Q Dimension from rotor outer periphery to flux barrier T Circumferential width of the base of the stator teeth

Claims

1. A rotor having a plurality of permanent magnets arranged around a rotating shaft; a stator disposed between the rotor and an air gap; having The stator includes: an annular stator yoke centered on the rotation axis; A plurality of stator teeth extending from the stator yoke toward the rotor; Slots formed between the stator teeth; having A winding is disposed in the slot; The stator teeth are a stator teeth base around which the winding is wound; a tip portion of the stator teeth forming an inner peripheral surface of the stator teeth facing the rotor; having The rotor has flux barriers extending from both ends of the permanent magnet toward a magnetic pole center of the permanent magnet, the flux barrier is formed along an outer circumferential surface of the rotor and is disposed closer to the stator than the permanent magnets, As the flux barrier, A front flux barrier formed in the rotation direction of the rotor; A rear flux barrier formed in the counter-rotation direction of the rotor; An electric motor having A small hole on the stator side is formed at the tip of the stator tooth, When a pair of stator teeth base side surfaces forming the stator teeth base are defined as a front stator teeth base side surface located in the rotation direction of the rotor and a rear stator teeth base side surface located in the opposite rotation direction of the rotor, and a circumferential width of the stator teeth base is T, the stator side small holes are disposed within a range of width 1 / 3T from a side surface of a base portion of the rear stator tooth, The front flux barrier is longer than the rear flux barrier; A rotor-side front small hole is formed at the rear end of the front flux barrier, a rotor-side rear small hole is formed at a front end of the rear flux barrier; The front flux barrier is formed within an angle α with respect to the center of the rotation axis, If the number of poles of the rotor is P, Based on the center of the magnetic pole The angle α is set to 4≦α≦120 / P The range was An electric motor characterized by:

2. The stator side small hole, the rotor side front small hole, and the rotor side rear small hole are gaps.

2. The electric motor according to claim 1 .

3. The stator side small hole, the rotor side front small hole, and the rotor side rear small hole are circular.

2. The electric motor according to claim 1 .

4. A dimension L from the inner peripheral surface of the stator tooth at the tip portion of the stator tooth to the stator side small hole is made smaller than a diameter of the stator side small hole.

2. The electric motor according to claim 1 .

5. The dimension M from the rotor outer circumferential surface to the rotor side front small hole is made smaller than the diameter of the rotor side front small hole.

2. The electric motor according to claim 1 .

6. The dimension N from the outer circumferential surface of the rotor to the rotor side rear small hole is made smaller than the diameter of the rotor side rear small hole.

2. The electric motor according to claim 1 .

7. A dimension Q from the outer circumferential surface of the rotor to the flux barrier is made smaller than a radial width of the flux barrier.

2. The electric motor according to claim 1 .

8. The number of the stator side small holes is one, and the number of the rotor side front small holes and the rotor side rear small holes is two each.

2. The electric motor according to claim 1 .

9. A compressor using the electric motor according to any one of claims 1 to 8, A compression mechanism is connected to the rotating shaft, The refrigerant is compressed by the compression mechanism. A compressor characterized by:

10. An apparatus using the compressor according to claim 9, The compressor, the condenser, the pressure reducing device, and the evaporator are connected in a ring shape by piping. An apparatus characterized by:

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