JP6470598B2 - Permanent magnet type rotating electric machine and compressor using the same - Google Patents

Description

  The present invention relates to a permanent magnet type rotating electric machine having a permanent magnet for a field in a rotor, and particularly suitable for use in a compressor in an air conditioner, a refrigerator, a freezer or a food showcase. The present invention relates to a rotary electric machine.

  2. Description of the Related Art Conventionally, in a permanent magnet type rotating electric machine, concentrated winding is adopted for a stator winding serving as an armature winding, and a permanent magnet is adopted for a field, thereby achieving miniaturization and high efficiency. As a means for reducing the size and increasing the efficiency of a permanent magnet type rotating electrical machine, it is possible to increase the surface area of the permanent magnet along the rotation axis direction and increase the amount of magnetic flux of the permanent magnet. In order to increase the amount of magnetic flux of the permanent magnet, it is necessary to devise the shape and arrangement of the permanent magnet.

  For example, a technique described in Patent Document 1 is known as a conventional technique related to the shape and arrangement of a permanent magnet used in a permanent magnet type rotating electrical machine. In this prior art, the shape of the permanent magnet embedded in the rotor is a substantially bathtub-like shape that protrudes radially inward. The specific shape of the permanent magnet has a central part extending perpendicularly to the magnetization direction in the cross section of the rotor, and two bending points at both ends in the circumferential direction of the central part. It is a shape which has two side parts extended toward the edge part side.

JP 2013-255371 A

  In the above prior art, the magnetization direction changes abruptly at two bending points formed between the central portion constituting the permanent magnet and the side portions connected to both ends thereof. For this reason, even if the surface area of the permanent magnet is increased, the amount of magnetic flux does not increase sufficiently, and it is difficult to obtain a desired amount of magnetic flux.

  Therefore, the present invention provides a permanent magnet type rotating electrical machine capable of increasing the amount of magnetic flux by increasing the surface area of the permanent magnet and a compressor using the permanent magnet type rotating electrical machine.

In order to solve the above problems, a permanent magnet type rotating electrical machine according to the present invention is embedded in a stator having a stator core and armature windings provided on the stator core, the rotor core, and the rotor core. that has a permanent magnet, and a rotor which stator opposed via a gap, the rotor, there is provided a permanent magnet minutes poles of the rotor, the permanent magnets, one The permanent magnet is accommodated in the permanent magnet insertion hole, and the permanent magnet is an arcuate central portion that protrudes inward in the radial direction of the rotor, and a linear 2 that extends from both ends of the central portion toward the outer peripheral surface of the rotor. possess a number of sides, a central portion and two side portions are separated from each other, the two sides is open toward the outer peripheral surface of the rotor, the central portion, the double radius is different It has an outer shape surrounded by two arcs and two straight lines with a length corresponding to the width of the center. Is equivalent to the width of the central part, the side part has a rectangular outer shape whose short side length is the same as the width of the central part, the straight line at the end of the central part and the short side part of the side part And the long side of the side portion is a tangent to the arc of the central portion, and the radial distance between the end surface closest to the inner peripheral surface of the rotor and the inner peripheral surface of the rotor in the central portion is L1, L1 ≦ L2 <L3 where L2 is the radial width of the central portion of the end surface and L3 is the radial distance between the outer surface of the rotor and the surface located on the opposite side of the end surface in the central portion. .

  The compressor according to the present invention includes a suction pipe that supplies a gas as a working fluid into a compression container, a compression mechanism that reduces the volume of the working fluid, a permanent magnet type rotating electrical machine that drives the compression mechanism, and a compression mechanism. A discharge pipe that discharges the working fluid compressed by the above to the outside of the compression container, and the permanent magnet type rotating electrical machine is a permanent magnet type rotating electrical machine according to the present invention.

  According to the present invention, the amount of magnetic flux can be effectively increased in accordance with the increase in the surface area of the permanent magnet. Thereby, a small and highly efficient permanent magnet type rotating electrical machine and compressor can be realized.

  Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

1 shows a cross-sectional view of a permanent magnet type rotating electric machine that is Embodiment 1 of the present invention. FIG. It is a cross-sectional view which shows the rotor core shape of the permanent magnet type rotary electric machine shown in FIG. FIG. 2 is a transverse sectional view showing a rotor core shape for one pole of the permanent magnet type rotating electric machine shown in FIG. 1. It is a cross-sectional view which shows the rotor core shape for 1 pole of the permanent-magnet-type rotary electric machine of a comparative example. It is a figure which shows the torque characteristic of the permanent-magnet-type rotary electric machine shown in FIG. 1, and a comparative example. It is a cross-sectional view which shows the rotor core shape for 1 pole of the permanent magnet type rotary electric machine which is Example 2 of this invention. It is a cross-sectional view which shows the rotor core shape for 1 pole of the permanent magnet type rotary electric machine which is Example 3 of this invention. It is a longitudinal cross-sectional view of the compressor which is Example 4 of this invention.

  In the present embodiment, the permanent magnet type rotating electrical machine includes a 6-pole rotor and a 9-slot stator. That is, the ratio of the number of rotor poles to the number of stator slots is 2: 3. The number of rotor poles, the number of stator slots, and the ratio thereof are not limited to the values in the present embodiment, and other values can provide the same effects as in the present embodiment. For example, the number of poles of the rotor may be 4 poles or 8 poles. The present embodiment is a so-called embedded magnet type rotating electrical machine in which a permanent magnet is embedded in a rotor core.

  In the following description, “axial direction” indicates the rotational axis direction of the rotor, “radial direction” indicates the radial direction of the rotor, and “circumferential direction” indicates the circumferential direction of the rotor.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a cross-sectional view of a permanent magnet type rotating electric machine that is Embodiment 1 of the present invention. The first embodiment operates as a permanent magnet type synchronous motor.

  As shown in FIG. 1, the permanent magnet type rotating electrical machine 1 includes a stator 2 and a rotor 3. The stator 2 includes a stator core 6 including a tooth 4 and a core back 5, and a concentrated armature winding wound around the tooth 4 in a slot 7 between the teeth 4 adjacent in the circumferential direction. 8 comprises. That is, the armature winding 8 is wound around the axial center of the tooth 4 radially arranged in the radial direction, and the U-phase winding 8a, the V-phase winding 8b, and W of the three-phase winding are circumferentially arranged. The phase windings 8c are arranged with a gap between them. Here, in the permanent magnet type rotating electrical machine 1, since the number of poles of the rotor 3 is 6 and the number of slots of the stator 2 is 9 slots, the slot pitch is 120 degrees in electrical angle. A shaft hole 15 for accommodating a cylindrical shaft (not shown) is formed at the center of the rotor 3.

  In the permanent magnet type rotating electrical machine 1 of the present embodiment, when a three-phase alternating current is passed through the armature winding 8 composed of the three-phase windings 8a to 8c, a rotating magnetic field is generated. The rotor 3 is rotated by the electromagnetic force acting on the permanent magnet 14 and the rotor core 12 by the rotating magnetic field.

  In order to reduce iron loss such as eddy current loss generated in the stator core 6 and the rotor core 12 when the permanent magnet type rotating electrical machine 1 is operated, the stator core 6 and the rotor core 12 are made of silicon steel plates. It is preferable to comprise a laminated body in which a plurality of thin plates made of magnetic steel plates are laminated.

  FIG. 2 is a cross-sectional view showing the rotor core shape of the permanent magnet type rotating electrical machine 1 shown in FIG. As shown in FIG. 2, the rotor 3 includes a permanent magnet insertion hole 13 having a substantially U-shaped cross section in a rotor core 12 having a shaft hole 15, and a ferrite permanent magnet 14 in the permanent magnet insertion hole 13. Is housed and fixed. The rotor 3 includes six permanent magnets 14 corresponding to the number of poles of the rotor 3, that is, six. The magnetic flux axis of the permanent magnet 14 is the d-axis, and the axis located at the magnetic pole separated from the d-axis by an electrical angle of 90 ° is the q-axis. A gap having a gap length g <b> 1 is formed in the radial direction between the outer peripheral surface of the rotor core 12 and the inner peripheral surface of the tooth 4. That is, the stator 2 and the rotor 3 are opposed to each other through the gap (g1).

  FIG. 3 is a cross-sectional view showing a rotor core shape for one pole of the permanent magnet type rotating electric machine shown in FIG. In FIG. 3, the permanent magnet 14 has two substantially linear side portions 41 extending from the radially outer side of the rotor 3 toward the radially inner side per pole, and is convex toward the radially inner side of the rotor 3. The arc-shaped central portion 40 is divided into three. That is, in the permanent magnet 14, the two side portions 41 extending from the radially outer side of the rotor 3 toward the radially inner side are defined by a predetermined curvature, and the substantially central portion thereof is formed on the rotor inner peripheral surface 3a. It connects to the both ends of the arcuate center part 40 which goes. Accordingly, the two side portions 41 extend from both end portions of the central portion 40 toward the outer peripheral surface of the rotor 3.

  The magnetization direction 16 indicated by the white arrow in FIG. 3 is continuously smooth between the radially inner surface of the central portion 40 constituting the permanent magnet 14 and the inner circumferential surface of the two side portions 41. To change. In particular, in the region including both ends of the central portion 40, a sudden change in the magnetization direction 16 is unlikely to occur. Thereby, it can magnetize reliably and the amount of magnetic flux by a permanent magnet can be ensured.

  With the above-described shape, the surface area of the permanent magnet 14 can be increased to effectively increase the amount of magnetic flux, and the rotor core cross-sectional area on the radially outer side of the permanent magnet 14 can be increased, so that the reluctance torque can be actively utilized. It becomes possible.

  As shown in FIG. 3, the distance between the end surface 40a closest to the rotor inner peripheral surface 3a in the central portion 40 and the rotor inner peripheral surface 3a (the inner wall surface of the shaft hole 15) is L1, and the end surface 40a of the central portion 40 is. The radial width (magnet thickness) of the central portion 40 at L2 is L2, and the diameter of the surface (radially inner surface) located on the opposite side to the end surface 40a of the central portion 40 and the outer peripheral surface 3b of the rotor The distance in the direction is L3. The permanent magnet 14 is configured such that these distances have a relationship of L1 ≦ L2 <L3. Such an arrangement relationship of the permanent magnets 14 in the rotor core 12 is preferable as the arrangement of the permanent magnets 14 having a shape capable of increasing the effective magnetic flux by expanding the magnet surface area as described above.

  Further, since the permanent magnet 14 is configured to have a relationship of L1 ≦ L2 <L3, the harmonic component of the in-machine magnetic flux due to the armature reaction is reduced, and the torque is increased by improving the power factor. A highly efficient permanent magnet type rotating electrical machine can be realized. In addition, a reduction in the amount of magnetic flux due to winding magnetization can be suppressed, and a small and highly efficient permanent magnet type rotating electrical machine is realized.

  The cross-sectional shape of the permanent magnet in the first embodiment will be described more specifically as follows.

  The central portion 40 and the two side portions 41 on both sides thereof are arranged symmetrically with respect to the d axis. Therefore, the permanent magnet 14 for one pole is arranged symmetrically with respect to the d axis. The central portion 40 has a center O ′ on the d-axis, has the same central angle (α) and is located radially inward of the center O ′, and the width of the central portion 40. The outer shape is surrounded by two straight lines having a length L2 corresponding to. The difference in radius between the two arcs corresponds to the width L2 of the central portion 40. The side portion 41 has a rectangular outer shape whose short side is the same as the width L <b> 2 of the central portion 40. The straight line at the end of the central portion 40 is in contact with the short side of the side portion. Here, the long side of the side portion 41 is a tangent to the arc of the central portion 40. In such a cross-sectional shape, the central angle α is set to a value smaller than 180 ° in terms of geometric angle. Therefore, the side part 41 is open toward the radial direction outer side. That is, the surface area along the axial direction of the permanent magnet 14 is increased, and the bending of the surface of the permanent magnet in the vicinity where the end portion of the central portion 40 and the end portion of the side portion 41 are in contact with each other can be moderated. Thereby, it can magnetize reliably and the magnetic flux by the permanent magnet 14 can be ensured.

  Further, in the first embodiment, as described above with reference to FIG. 3, the permanent magnet 14 is configured and arranged in the rotor core so that L1 ≦ L2 <L3 in FIG. The magnetic flux can be increased to ensure magnet torque, and the rotor core cross-sectional area can be increased to ensure reluctance torque.

  The curvature of the central portion 40 of the permanent magnet 14 can be appropriately set according to the size (diameter) and the number of poles of the rotor 3. Even in this case, the surface area (area in the cross section) of the permanent magnet 14 in the rotor 3 can be increased by setting so that the relationship of L1 ≦ L2 <L3 is satisfied. Can be realized. In addition, when the number of poles of the rotor is a general 4-pole, 6-pole, or 8-pole, as the radius of curvature increases, from both ends of the arc-shaped central portion 40 along the substantially radial direction. Thus, the opening angle of the two side portions 41 extending toward the outer peripheral side of the rotor 3 is increased. Therefore, it is preferable to set the curvature radius of the central portion 40 in consideration of the number of poles to be adopted.

  Here, a comparative example will be described with reference to FIG.

  FIG. 4 is a cross-sectional view showing a rotor core shape for one pole of a permanent magnet type rotating electrical machine of a comparative example. In this comparative example, the other configuration of the magnet shape is the same as that of the first embodiment.

  As shown in FIG. 4, the rotor 3 ′ of the comparative example has two bending points 42 in the circumferential direction, and a linear central portion 40 ′ having the two bending points 42 as ends, Permanent magnet 14 'is comprised from the substantially linear side part 41' extended | stretched to radial direction outer side from each bending point 42. FIG. In FIG. 4, the magnetization direction 16 ′ indicated by the white arrow changes rapidly in the vicinity of each bending point 42.

  Further, as shown in FIG. 4, the distance between the radially inner surface of the central portion 40 ′ and the rotor inner peripheral surface 3a ′ (the inner wall surface of the shaft hole 15) is L1, and the radial direction of the central portion 40 ′. When the width (magnet thickness) is L2, and the radial distance between the radially outer surface of the central portion 40 ′ and the rotor outer peripheral surface 3b ′ is L3, these distances are the same as those in Example 1 (L1 ≦ L2 <L3). ), L2 <L1 <L3. In the configuration of such a comparative example, the amount of magnetic flux obtained by winding magnetization decreases in the vicinity of the two bending points 42. Furthermore, even if the central portion 40 ′ of the permanent magnet 14 ′ is arranged on the radially inner side (rotor inner peripheral surface 3a ′ side) and the relationship between L1, L2, and L3 is made closer to the relationship of the first embodiment, Similarly, the magnetic flux due to winding magnetization decreases. That is, in the vicinity of the bending point 42, magnetizations having different magnetization directions 16 ′ are mixed, so that a desired amount of magnetic flux cannot be secured, and it is difficult to increase the amount of magnetic flux by expanding the surface area of the permanent magnet 14 ′.

  In the comparative example of FIG. 4, even if the permanent magnet 14 ′ is divided into three substantially linear side portions 41 ′ and substantially linear central portions 40 ′, similarly, in the vicinity of the bending point 42, Since magnetizations having different magnetization directions 16 ′ are mixed, it is difficult to increase the amount of magnetic flux by increasing the surface area of the permanent magnet 14 ′.

  Next, torque characteristics of the permanent magnet type rotating electrical machine 1 of this embodiment and the permanent magnet type rotating electrical machine 1 'of the comparative example shown in FIG. 4 will be described.

  FIG. 5 is a diagram showing the torque characteristics of the permanent magnet type rotating electrical machine 1 shown in FIG. 1 together with the torque characteristics of the comparative example. In FIG. 5, the rated current is 1 P.U. (Per Unit), and the torque (high speed range) of the permanent magnet type rotating electrical machine 1 (example) when the rated current is passed is 1 P.U. It has become. Note that the relationship between the torque and the armature current shown in FIG. 5 is based on the result of examination by the present inventors.

  As shown in FIG. 5, the torque of the permanent magnet type rotating electrical machine 1 of this embodiment is larger than that of the permanent magnet type rotating electrical machine 1 'of the comparative example shown in FIG. The degree of increase in torque is particularly great at high speeds. Therefore, according to the permanent magnet type rotating electrical machine 1 of the present embodiment, it is possible to improve the power factor decrease due to the effect of the armature reaction and the decrease in the magnetic flux amount due to the winding magnetization, and the torque characteristics are improved. A highly efficient permanent magnet type rotating electrical machine can be realized.

  The permanent magnet 14 of the present embodiment is configured and arranged in the rotor core so that L1 ≦ L2 <L3 as shown in FIG. 3, but L1 ≦ L2 depending on the desired motor specifications. The permanent magnet 14 may be configured and arranged so that the above relationship is satisfied. Thereby, as shown in FIG. 3, the change of the magnetization direction of a permanent magnet can be made smooth.

  Hereinafter, two different assembling methods for inserting the permanent magnet 14 into the permanent magnet insertion hole 13 provided in the rotor core 12 according to the method of manufacturing the permanent magnet rotating electrical machine of the present embodiment will be described.

  In the first assembling method, first, the two side portions 41 are fixed to both end portions of the central portion 40 having a circular cross section by an adhesive or the like. Next, the permanent magnet 14 in which the two side portions 41 are fixed and integrated at the center portion 40 and both end portions thereof is inserted into the permanent magnet insertion hole 13 from the outside in the axial direction and fixed. Thereby, the rotor 3 shown in FIG. 3 is obtained.

  In the second assembling method, the central portion 40 having a circular cross section is inserted into the permanent magnet insertion hole 13 from the outside in the axial direction. Thereafter, an adhesive or the like is poured into both end portions of the central portion 40 inserted into the permanent magnet insertion hole 13. Subsequently, the two side portions 41 are respectively inserted into the permanent magnet insertion holes 13 from the outside in the axial direction. At this time, excess adhesive flows out of the permanent magnet insertion hole 13 by the two side portions 41 press-fitted into the permanent magnet insertion hole 13. Then, the rotor 3 shown in FIG. 3 is obtained by removing excess adhesive. In addition, in order to fix these three divided | segmented center parts 40 and the two side parts 41, the injection | pouring of the adhesive agent etc. to the both ends of the center part 40 inserted in the permanent magnet insertion hole 13 is preferable. Further, after inserting the central portion 40 into the permanent magnet insertion hole 13, only the two side portions 41 are inserted into both ends of the central portion 40. The permanent magnet insertion hole 13 may be fastened. In this case, pouring of an adhesive or the like can be omitted.

  As described above, according to the present embodiment, the amount of magnetic flux can be reliably ensured by increasing the surface area of the permanent magnet, so that torque characteristics are improved and a small and highly efficient permanent magnet type rotating electrical machine can be realized.

  Further, according to the present embodiment, even in the case where the high load and the armature winding are increased and the inductance is increased in the high speed range, the harmonic component of the in-machine magnetic flux due to the armature reaction is reduced, and the force is reduced. High torque can be achieved by improving the rate. Moreover, the fall of the magnetic flux amount obtained by coil | winding magnetization can be suppressed.

  In addition, by dividing the permanent magnet for one pole in the present embodiment as described above, the centrifugal force acting on the permanent magnet is dispersed while increasing the surface area of the permanent magnet, or the permanent magnet as shown in FIG. The complicated stress due to the cross-sectional shape is suppressed. As a result, the strength of the rotor is improved. Further, by dividing the permanent magnet, the eddy current generated in the permanent magnet can be reduced while increasing the surface area of the permanent magnet.

  Note that the number of divisions of the permanent magnet is not limited to three divisions, and the central portion or the side portion of the permanent magnet may be further divided to have a division number of 3 or more such as four divisions or five divisions. However, if the number of divisions is increased, the assembly time of the rotor by the above-described mounting method increases. Therefore, considering the time and cost required for manufacturing, in order to obtain the effect on the electrical or mechanical characteristics or performance of the rotating electrical machine by dividing the permanent magnet in this embodiment, the three division is suitable.

  In the present embodiment, the permanent magnet for one pole is divided into three parts at the central part and two side parts, but these central part and two side parts may be formed of a continuous magnet material and integrated. Even in this case, as in the first embodiment, a sudden change in the magnetization direction is alleviated in the region including both ends of the central portion.

  In this embodiment, a ferrite magnet is used as the permanent magnet, but a permanent magnet made of another magnet material, for example, a rare earth permanent magnet may be used. Ferrite, which is a magnet material in this embodiment, is less expensive than other magnet materials such as rare earth materials, but has a small residual magnetic flux density. However, according to this embodiment, the magnetic flux is reliably increased by increasing the surface area of the permanent magnet. Since the amount can be secured, a small and highly efficient permanent magnet type rotating electrical machine can be realized by using a ferrite magnet.

  FIG. 6 is a transverse sectional view showing a rotor core shape for one pole of a permanent magnet type rotating electric machine that is Embodiment 2 of the present invention. The same components as those in FIG. 3 are denoted by the same reference numerals. Hereinafter, differences from the first embodiment will be mainly described.

  In the second embodiment, unlike the first embodiment, the rotor core 12 is positioned at a position adjacent to the radially outer ends of the two substantially linear side portions 41 constituting the permanent magnet in the outer peripheral portion of the rotor core 12. A notch (concave portion) is provided from the surface of the iron core 12 toward the outer periphery of the rotor iron core.

  As shown in FIG. 6, in the outer peripheral portion of the rotor core 12, the ends 41 a of the two substantially linear side portions 41 constituting the permanent magnet 14, that is, the ends located on the radially outer peripheral side of the rotor core 12. A notch (recess) 11 having a bottom surface that is recessed from the rotor outer peripheral surface 3b into the outer peripheral portion of the rotor core 12 and has a bottom surface substantially parallel to the width direction of the end portion 41a is provided at a portion facing the portion 41a. It is done. Further, the notch (recess) 11 is provided so as to extend in the axial direction of the rotor 3.

  As a result, the outer peripheral shape of the rotor core 12 (rotor outer peripheral surface 3b) is such that the gap between the inner peripheral surface of the teeth 4 constituting the stator 2 is the gap length g1 and the gap is the maximum gap. It becomes the structure which has the notch part (recessed part) 11 which has the substantially linear bottom face which becomes long g2 (g2> g1). Note that the gap length g2 is the deepest depth of the notch 11 that is the deepest between the end 41a in FIG. 6 and the end of the permanent magnet that is adjacent to the end 41a and forms the adjacent pole (not shown). It corresponds to. That is, on the outer peripheral surface of the rotor core 12, the position where the gap between the notch portion 11 and the inner peripheral surface of the tooth 4 becomes the maximum gap length g2 Part, that is, located on the outer side in the circumferential direction from the corner of each side 41. Accordingly, the circumferential length of each notch portion 11 is equal to or greater than the circumferential length of the end portion 41a of each side portion 41, that is, the width L2.

  Moreover, as shown in FIG. 6, the arc-shaped portion of the rotor outer peripheral surface 3b that forms a gap having a gap length g1 between the inner peripheral surface of the teeth 4 has an angle θp of 90 ° to 120 ° in electrical angle. It is comprised so that it may become.

  According to the present embodiment, the rotor outer peripheral surface 3b and the inner peripheral surface of the tooth 4 at the positions corresponding to the radially outer ends 41a of the two side portions constituting the permanent magnet 14 are formed by the notch portion 11. The gap length of the gap formed by is increased. For this reason, since the magnetic resistance increases in the q-axis direction, the magnetic flux of the permanent magnet can be concentrated in the d-axis direction. As a result, the influence of the armature reaction can be suppressed, and the harmonic component of the in-machine magnetic flux can be reduced.

  Furthermore, since the bottom surface of the notch portion 11 is parallel to the width direction of the end portion 41 a of the side portion 41, the thickness of the portion of the rotor core 12 between the end portion 41 a and the bottom surface of the notch portion 11 is ensured. Thus, the strength of this portion is ensured. For this reason, even if it provides the notch part 11, the side part 41 of the permanent magnet 14 which a centrifugal force works can be supported reliably.

  Also in this embodiment, the power factor decrease due to the effect of the armature reaction and the decrease in the magnetic flux amount due to the winding magnetization can be improved, the torque decrease can be suppressed, and a small and highly efficient permanent magnet type A rotating electrical machine can be realized. That is, the same effect as in the first embodiment can be obtained.

  FIG. 7 is a cross-sectional view showing a rotor core shape for one pole of a permanent magnet type rotating electric machine that is Embodiment 3 of the present invention. The same components as those in FIG. 3 are denoted by the same reference numerals. Hereinafter, differences from the first embodiment will be mainly described.

  In the present embodiment, unlike the first embodiment, a part 120 of the rotor core 12 is interposed between the central portion 40 and the side portion 41 of the permanent magnet 14. In addition, the other structure including the shape and arrangement | positioning of the center part and side part of the permanent magnet 14 is the same as that of Example 1 (refer FIG. 3).

  As shown in FIG. 7, in this embodiment, the permanent magnet insertion hole into which the permanent magnet 14 for one pole is inserted is divided into three permanent magnet insertion holes 13a, 13b, and 13c. The central portion 40 of the permanent magnet 14 is inserted into the permanent magnet hole 13a, and the two side portions 41 of the permanent magnet 14 are inserted into the permanent magnet insertion holes 13b and 13c. For this reason, if the center part 40 and the side part 41 of the permanent magnet 14 are inserted in the permanent magnet insertion holes 13a, 13b, and 13c, the permanent magnet insertion hole 13a is interposed between the center part 40 and the side part 41 of the permanent magnet 14. , 13b and a part 120 of the rotor core that divides the permanent magnet insertion holes 13a, 13c is interposed.

  According to the present embodiment, the central portion 40 of the permanent magnet 14 on which centrifugal force works is supported by the portion 120 of the rotor core 12 interposed between the central portion 40 and the side portion 41. Moreover, since each part of the permanent magnet divided | segmented into 3 is each inserted in an individual insertion hole, the centrifugal force which acts on a permanent magnet is disperse | distributed. As a result, the strength of the rotor 3 is improved while the surface area of the permanent magnet is increased.

  FIG. 8 is a longitudinal sectional view of a compressor that is Embodiment 4 of the present invention. The permanent magnet type rotating electrical machine according to any of the first to third embodiments described above is applied to the compressor of the present embodiment.

  As shown in FIG. 7, in the compressor 50, the spiral wrap 62 standing upright on the end plate 61 of the fixed scroll member 60 and the end plate 64 of the orbiting scroll member 63 stand upright in the cylindrical compression container 69. A spiral wrap 65 is provided, and the spiral wrap 62 of the fixed scroll member 60 and the spiral wrap 65 of the orbiting scroll member 63 are engaged with each other. The compressor 50 includes a permanent magnet type rotating electrical machine 1 that transmits a turning force to the orbiting scroll member 63 via the crankshaft 72 in the compression container 69. The orbiting scroll member 63 orbits through the crankshaft 72 by the permanent magnet type rotating electrical machine 1 that operates as a permanent magnet type synchronous motor, thereby performing a compression operation.

  Specifically, of the compression chambers 66a, 66b, 66c, 66d, and 66e formed by the fixed scroll member 60 and the orbiting scroll member 63, the compression chambers 66a and 66b that are positioned on the outermost diameter side are associated with the orbiting motion. By moving toward the center of the fixed scroll member 60 and the orbiting scroll member 63, the volume is gradually reduced and the compression operation is performed. When the compression chambers 66a and 66b reach the vicinity of the center of the fixed scroll member 60 and the orbiting scroll member 63, the compressed gas (gas) as the working fluid in the compression chambers 66a and 66b supplied from the suction pipe 71 is compressed into the compression chamber 66e. Is discharged into the compression container 69 from a discharge port 67 communicating with the air. The compressed gas to be discharged passes through gas passages (not shown) provided in the fixed scroll member 60 and the frame 68 to reach the compression container 69 below the frame 68 and from a discharge pipe 70 provided on the side wall of the compression container 69. It is discharged out of the compressor 50.

  The permanent magnet type rotating electrical machine 1 that drives the compressor 50 is controlled by a separate inverter device (not shown) and rotates at a rotation speed suitable for the compression operation. Here, the permanent magnet type rotating electrical machine 1 includes a stator 2 and a rotor 3, and a crankshaft 72 provided in the rotor 3 is a shaft hole 15 in the first to third embodiments (FIGS. 3, 6, and 7). Mounted on. When the crankshaft 72 is rotated by the permanent magnet type rotating electrical machine 1, the orbiting scroll member 63 does not rotate but performs a revolving orbiting motion with a predetermined eccentric amount at the upper portion of the crankshaft 72 as a radius. An oil hole 74 is provided inside the crankshaft 72, and as the crankshaft 72 rotates, the lubricating oil in the oil reservoir 73 at the lower part of the compression container 69 is supplied to the slide bearing 75 through the oil hole 74. The By applying the permanent magnet type rotating electrical machine 1 of any of the first to third embodiments to such a compressor 50, the efficiency of the compressor can be improved and energy saving can be achieved.

  At the time of manufacturing the compressor 50, in the assembly process of the permanent magnet rotating electrical machine 1, permanent magnets that are not magnetized are inserted and embedded in the rotor core 12. After the permanent magnet type rotating electrical machine 1 is assembled, a permanent magnet embedded in the rotor core is magnetized by passing a large current through the armature winding, that is, the stator winding. In addition, you may use not only such a winding magnetizing method but another magnetizing method.

  By the way, many current home and commercial air conditioners have the R410A refrigerant sealed in the compression container 69, and the ambient temperature of the permanent magnet type rotating electrical machine 1 is often 80 ° C. or more. In the future, as the adoption of R32 refrigerant having a smaller global warming potential proceeds, the ambient temperature further increases. In particular, the permanent magnet 14 decreases in the residual magnetic flux density of the magnet due to a high temperature, and the armature current increases in order to ensure the same output. By applying, efficiency reduction can be suppressed.

  In addition, in applying the permanent magnet type rotary electric machine 1 of Examples 1 to 3 described above to the compressor of Example 4, the type of refrigerant is not limited. Moreover, the permanent magnet type rotary electric machine 1 of Examples 1-3 is applicable not only to a scroll compressor but to the compressor which has other compression mechanisms, such as a rotary compressor.

  According to the present embodiment, a compressor capable of saving energy can be realized by applying a small and highly efficient permanent magnet type rotating electrical machine. In addition, by applying the permanent magnet type rotating electrical machine of the first to third embodiments, it is possible to widen the operating range of the compressor, such as enabling high speed operation.

  Further, refrigerants such as He (helium) and R32 have a larger leakage from the gap in the compressor than refrigerants such as R22, R407C, and R410A. For this reason, at the time of low speed driving | operation, since the ratio of the leakage with respect to the circulation amount becomes large, efficiency falls. In order to improve the efficiency at the time of low circulation (low speed operation), it is effective to reduce the leakage loss by downsizing the compression mechanism and increasing the rotational speed to obtain the same circulation. Furthermore, it is preferable to increase the maximum rotational speed in order to secure the maximum circulation amount. On the other hand, by applying the permanent magnet type rotating electrical machine 1 of the first to third embodiments described above to the compressor, it is possible to increase the maximum torque and the maximum number of revolutions, and to reduce the loss in the high speed range. Therefore, the efficiency can be improved when a refrigerant such as He or R32 is used.

  As described above, by applying the permanent magnet type rotating electrical machines of Examples 1 to 3 to the compressor, a highly efficient compressor can be realized and energy saving can be achieved.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  For example, the permanent magnet rotating electrical machine according to the present invention can be applied not only to a compressor but also to other devices.

DESCRIPTION OF SYMBOLS 1 ... Permanent magnet type rotary electric machine 2 ... Stator 3, 3 '... Rotor 3a, 3a' ... Rotor inner peripheral surface 3b, 3b '... Rotor outer peripheral surface 4 ... Teeth 5 ... Core back 6 ... Stator core 7 ... Slot 8, 8a, 8b, 8c ... Armature winding 11 ... Notch (recess)
12, 12 '... Rotor cores 13, 13', 13a, 13b, 13c ... Permanent magnet insertion holes 14, 14 '... Permanent magnet 15 ... Shaft hole 16, 16' ... Magnetization direction 40 ... Central part 41 ... Side part 41a ... end 42 ... bending point 50 ... electric compressor 60 ... fixed scroll members 61 and 64 ... end plates 62 and 65 ... spiral wraps,
63 ... Orbiting scroll members 66a, 66b, 66c, 66d, 66e ... Compression chamber 67 ... Discharge port 68 ... Frame 69 ... Compression container 70 ... Projection pipe,
71 ... Suction pipe 72 ... Crank shaft 73 ... Oil retaining part 74 ... Oil hole 75 ... Sliding bearing 120 ... Part of the rotor core

Claims (5)

A stator having a stator core and armature windings provided on the stator core;
A rotor core, wherein and a permanent magnet that will be embedded in the rotor core, a rotor facing the stator with a gap,
Equipped with a,
In the permanent magnet type rotating electric machine, the rotor includes the permanent magnets corresponding to the number of poles of the rotor .
The permanent magnet is accommodated in one permanent magnet insertion hole,
The permanent magnet is
An arcuate central portion that protrudes radially inward of the rotor;
Two linear side portions extending from both ends of the central portion toward the outer peripheral surface of the rotor;
I have a,
The central portion and the two side portions are divided from each other;
The two side portions are open toward the outer peripheral surface of the rotor,
The central portion has an outer shape surrounded by two arcs having different radii and two straight lines having a length corresponding to the width of the central portion, and a difference between the radii of the two arcs is determined by the width of the central portion. Equivalent,
The side portion has a rectangular outer shape in which the length of the short side is the same as the width of the central portion,
The straight line at the end of the central part is in contact with the short side of the side part,
The long side of the side portion is tangent to the arc of the central portion,
The radial distance between the end surface closest to the inner peripheral surface of the rotor in the central portion and the inner peripheral surface of the rotor is L1, the radial width of the central portion on the end surface is L2, and the central portion A permanent magnet type rotating electrical machine characterized in that L1 ≦ L2 <L3, where L3 is a radial distance between a surface located on a side opposite to the end surface in the radial direction and an outer peripheral surface of the rotor . In the permanent magnet type rotating electrical machine according to claim 1,
The rotor core has a plurality of concave portions provided on an outer peripheral portion of the rotor facing a radial end portion of the two side portions . In the permanent magnet type rotating electrical machine according to claim 2,
The permanent magnet rotating electrical machine according to claim 1, wherein a bottom surface of the concave portion is parallel to a width direction of radial end portions of the two side portions . In the permanent magnet type rotating electrical machine according to claim 1,
The permanent magnet type rotating electrical machine , wherein the permanent magnet is made of a ferrite magnet . A suction pipe for supplying a working fluid gas into the compression vessel;
A compression mechanism for reducing the volume of the working fluid;
A permanent magnet type rotating electrical machine that drives the compression mechanism;
A discharge pipe for discharging the working fluid compressed by the compression mechanism out of a compression container;
A compressor comprising:
The permanent magnet type rotating electrical machine is:
A stator having a stator core and armature windings provided on the stator core;
A rotor core, and a permanent magnet embedded in the rotor core, the rotor facing the stator via a gap;
With
The rotor includes the permanent magnets for the number of poles of the rotor,
The permanent magnet is accommodated in one permanent magnet insertion hole,
The permanent magnet is
An arcuate central portion that protrudes radially inward of the rotor;
Two linear side portions extending from both ends of the central portion toward the outer peripheral surface of the rotor;
Have
The central portion and the two side portions are divided from each other;
The two side portions are open toward the outer peripheral surface of the rotor,
The central portion has an outer shape surrounded by two arcs having different radii and two straight lines having a length corresponding to the width of the central portion, and a difference between the radii of the two arcs is determined by the width of the central portion. Equivalent,
The side portion has a rectangular outer shape in which the length of the short side is the same as the width of the central portion,
The straight line at the end of the central part is in contact with the short side of the side part,
The long side of the side portion is tangent to the arc of the central portion,
The radial distance between the end surface closest to the inner peripheral surface of the rotor in the central portion and the inner peripheral surface of the rotor is L1, the radial width of the central portion on the end surface is L2, and the central portion , Wherein L1 ≦ L2 <L3, where L3 is a radial distance between a surface located on the opposite side of the end surface in the radial direction and the outer peripheral surface of the rotor.

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