JP2014180094A - Permanent magnet rotary electric machine and elevator driving winch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a permanent magnet rotary electric machine structured to reduce torque pulsation while suppressing increase in cost of manufacture and further to provide an elevator driving winch capable of performing a smooth elevating/lowering operation while suppressing increase in cost of manufacture by the permanent magnet rotary electric machine.SOLUTION: Permanent magnets are disposed at both sides of a plurality of unit rotor cores forming a rotor, and a protrusive portion where the unit rotor core protrudes from an outer circumferential edge of the permanent magnet is provided in the unit rotor core. On one surface of the protrusive portion, a planar part extending to an outer circumferential side is formed as the same surface as a surface with which one permanent magnet is contacted. On the other surface of the protrusive portion, a protruding part is formed which protrudes while extending in a circumferential direction so as to cover a part of an outer circumferential part of the other permanent magnet with respect to a surface with which the other permanent magnet is contacted. The rotor is separated into two layers in an axial direction of a rotary shaft, the protruding part of one rotor core forming the rotor and the protruding part of the other rotor core forming the rotor protrude oppositely in the circumferential direction of the rotor.

Description

  The present invention relates to a permanent magnet rotating electric machine, and in particular, a permanent magnet rotating electric machine in which a magnet portion and a magnetic material portion (rotor core) of a rotor are alternately arranged radially, and an elevator drive hoist using the same. Related to the machine.

  In general, a permanent magnet rotating electric machine is relatively used as an electric motor used in various industrial fields. This permanent magnet rotating electric machine is a synchronous motor using a permanent magnet for the rotor field (magnetic pole). By the way, in order to improve the performance of the permanent magnet rotating electric machine, it is known that the magnetic force of the permanent magnet used should be increased. For this reason, a rare earth magnet represented by a neodymium magnet is used as a magnet having a strong magnetic force. It is increasingly used. Thereby, a small and high output permanent magnet rotating electric machine can be obtained.

  And as a typical industrial field | area where such a rotary electric machine is used, there exists an elevator system installed in the building structure. In this elevator system, a permanent magnet rotating electric machine is used for an elevator driven hoisting machine, whereby a car carrying a passenger is wound up.

  Permanent magnet synchronous motors that achieve both high torque density and low torque pulsation are used for elevator-driven hoisting machines that require small size, light weight, and low vibration. As described above, the permanent magnet synchronous motor employs a neodymium magnet having a high energy density. Neodymium, the main raw material for neodymium magnets, and dysprosium used to increase the coercivity of neodymium magnets are rare earth elements.

  However, due to the recent surge in rare earth elements, the ratio of magnet cost to the total cost of permanent magnet rotating electrical machines using neodymium magnets has increased. It is required to use a magnet or a permanent magnet that does not use a rare earth element. For this reason, ferrite magnets with a rare earth element content less than neodymium magnets are attracting attention again.

  The magnetic force of a ferrite magnet is about 1/3 that of a neodymium magnet. When a neodymium magnet is replaced with a ferrite magnet, the shortage of torque due to a decrease in magnetic force needs to be compensated for by increasing the magnet surface area, so that the overall size of the motor increases. This is a very serious problem for elevator-driven hoists where installation space is severely limited. Therefore, there is a demand for a permanent magnet rotating electrical machine that can realize a high torque density with a low-magnetism magnet such as a ferrite magnet.

  A permanent magnet rotating electric machine used in an elevator drive hoist is mainly a surface magnet type (SPM / Surface Permanent Magnet Motor) rotating electric machine in which a permanent magnet is attached to the surface of a rotor. However, in this structure, the surface area of the magnet cannot be increased beyond the area of the air gap (opposite area of the rotor and stator), and it is difficult to make the magnetic flux density in the air gap higher than the residual magnetic flux density of the magnet. there were. Therefore, with such a structure, it has been difficult to achieve a high torque density using a low-magnetism permanent magnet such as a ferrite magnet.

  On the other hand, as a permanent magnet rotating electric machine that realizes high torque density, for example, typically, Japanese Patent Laid-Open No. 2000-217286 (Patent Document 1) and Japanese Patent Laid-Open No. 63-140645 (Patent Document 2). There is a brushless DC motor disclosed in Japanese Patent Application No. 2004-110826. The magnet part and the magnetic material part (rotor core) of the rotor of this electric motor are alternately arranged radially. That is, the permanent magnet rotating electrical machines of these patent documents have a structure in which the magnets are radially arranged so that the magnetization of the magnet of the rotor is perpendicular to the radial direction. By arranging the magnet in this way, the surface area of the magnet can be increased along the radial direction, so that the magnetic flux density in the air gap between the rotor and the stator can be increased.

  As described above, in the case of a surface magnet type rotor, the magnetic flux density in the air gap does not exceed the residual magnetic flux density of the magnet. However, the magnetic flux density in the air gap of the permanent magnet rotating electrical machine disclosed in the patent document can exceed the residual magnetic flux density of the magnet by optimizing the aspect ratio of the rotor core. Therefore, even when a low magnetic force magnet such as a ferrite magnet is used, a torque density comparable to that of a neodymium magnet can be realized.

JP 2000-217286 A Japanese Patent Laid-Open No. 63-140645

  In the permanent magnet rotating electrical machine disclosed in the above-mentioned patent document that realizes a high torque density, the rotor is skewed in order to reduce torque pulsation. It is generally possible to cancel the pulsation component by adding a phase difference of 30 degrees in electrical angle (product of mechanical angle and pole pair number) at the both ends in the axial direction of the rotor, or an electrical angle corresponding to a half cycle of cogging torque in the rotational direction. Are known. Therefore, when manufacturing a rotor, it is necessary to laminate | stack an electromagnetic steel plate, shifting in a rotation direction.

  Patent Document 1 discloses a so-called continuous skew type rotor in which magnetic steel sheets are stacked while being shifted in the rotation direction so that the magnetic pole shape is smooth in the axial direction. Patent Document 2 discloses a so-called step skew type rotor in which the rotor is divided into six stages in the axial direction and stacked while being shifted in the rotation direction.

  One of the problems with these rotors is that the structure is complicated, making it difficult to manufacture the rotor. In particular, the continuous skew type of Patent Document 1 places a heavy burden on the lamination work (workability, assembly, etc.) of electromagnetic steel sheets, and further, the shape of the permanent magnet becomes complicated, making it difficult to process the magnet. Moreover, since the step skew type of Patent Document 2 needs to divide the permanent magnet in the axial direction, the number of parts increases and the burden on assembly work increases. These all lead to an increase in manufacturing costs.

  As described above, the permanent magnet rotating electrical machine described in the patent literature still needs to be improved in terms of achieving both a reduction in torque pulsation and a reduction in manufacturing cost. Moreover, when such a permanent magnet rotating electric machine is used for an elevator drive hoist, the manufacturing cost becomes high.

  It is an object of the present invention to provide a permanent magnet rotating electric machine having a structure that reduces torque pulsation while suppressing an increase in manufacturing cost, and further performs a smooth lifting operation while suppressing an increase in manufacturing cost. The object is to provide an elevator-driven hoisting machine.

  A feature of the present invention is that permanent magnets are arranged on both sides of a plurality of unit rotor cores forming a rotor, and a protruding portion from which the unit rotor core jumps out from the outer peripheral end of the permanent magnet is provided in the unit rotor core. One surface of the protruding portion is formed with a flat portion extending to the outer peripheral side as the same surface that is in contact with one permanent magnet, and the other surface of the protruding portion is provided with the other permanent magnet. A protruding portion that extends in the circumferential direction so as to cover a part of the outer peripheral portion of the other permanent magnet with respect to the surface with which the magnet is in contact is formed.

  Further, at least the rotor is separated into two layers in the axial direction of the rotating shaft, and the protruding direction of the protruding portion of the rotor core constituting one rotor and the protruding direction of the protruding portion of the rotor core constituting the other rotor are It is located in the opposite direction in the circumferential direction of the rotor.

  According to the present invention, since the two rotors are formed with a common unit rotor core, an increase in manufacturing cost can be suppressed, and the protruding portions of the unit rotor cores constituting the two rotors can be reversed. By setting the direction, the pulsation component of the cogging torque can be effectively canceled out.

It is sectional drawing which shows the cross section of the radial direction of the permanent magnet rotary electric machine to which this invention is applied. FIG. 3 is an enlarged cross-sectional view in which only a part of the radial cross section of the permanent magnet rotating electric machine according to the first embodiment of the present invention is cut out and enlarged. FIG. 3 is an enlarged cross-sectional view in which only a part of the cross section of the rotor core shown in FIG. 2 is cut out and enlarged. It is an expanded sectional view for demonstrating the suitable length of the protrusion part formed in the rotor core shown in FIG. FIG. 3 is an enlarged perspective view of a part of the rotor of the permanent magnet rotating electric machine shown in FIG. It is a characteristic view which shows the simulation result of the cogging torque of the permanent magnet rotary electric machine of the 1st Embodiment of this invention. It is explanatory drawing which shows the result of Fourier series expansion | deployment of the cogging torque waveform of FIG. It is the expansion perspective view which cut off only part of the rotor of the permanent magnet rotary electric machine which becomes the 2nd Embodiment of this invention, and was seen from the diagonal. It is the expanded sectional view which cut out only a section of the diameter direction of the permanent magnet rotary electric machine which becomes the 3rd embodiment of the present invention, and expanded it. It is sectional drawing of the axial direction of the elevator drive hoist using the permanent magnet rotary electric machine which becomes this invention. It is the expansion perspective view which cut off a part of rotor of the conventional permanent magnet rotary electric machine, and was seen from the diagonal.

  Embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments, and various modifications and application examples are included in the technical concept of the present invention. It is included in the range.

  A first embodiment of the present invention will be described with reference to FIGS. 1 to 7. FIG. 1 is a cross-sectional view showing a radial cross section of a permanent magnet rotating electric machine, and FIG. 2 is a permanent magnet rotation shown in FIG. FIG. 3 is an enlarged sectional view in which only a part of the radial cross section of the electric machine is cut out and enlarged, FIG. 3 is an enlarged sectional view in which a part of the rotor core shown in FIG. 2 is cut out and enlarged, and FIG. FIG. 5 is an enlarged cross-sectional view for explaining an appropriate length of a protrusion formed on the rotor core shown in FIG. 3, and FIG. 5 is a partial cutaway view of the rotor of the permanent magnet rotating electric machine shown in FIG. FIG.

  In FIG. 1, a permanent magnet rotating electrical machine 1 generally includes a stator 2 and a rotor 3, and the stator 2 and the rotor 3 face each other circumferentially with a predetermined air gap G interposed therebetween. ing. The stator 2 is provided with a plurality of stator salient poles 42 at predetermined angles, and the stator windings 5 are wound around the individual stator salient poles 42.

  The rotor 3 includes a hollow rotating shaft 10, a non-magnetic ring 9 disposed around the rotating shaft 10, and an annular rotor core 7 fixed to the outer periphery of the rotor shaft 10. 7, a plurality of permanent magnets 6 are radially provided at predetermined angles. When electric power is supplied to the stator winding 5, the rotor 3 starts to rotate in response to this and gives a predetermined rotational torque to the rotary shaft 10. Since the basic configuration and operation of such a rotating electric machine are already well known, further explanation is omitted.

  Next, the first embodiment of the present invention will be described in detail with reference to FIG. 2 in which only a part of the radial cross section of the permanent magnet rotating electrical machine is cut out and enlarged.

  In FIG. 2, the stator 2 includes a stator core 4 and a stator winding 5. The stator core 4 is configured by laminating electromagnetic steel plates punched by a punching die or the like. The stator core 4 is located at the outer peripheral portion and forms a stator magnetic path, and the stator core back 41 extends radially from the stator core back 41 toward the inner periphery of the stator 2 at a predetermined angular pitch. And a stator salient pole (stator teeth) 42. A space formed between the adjacent stator salient poles 42 and the stator core back 41 is a slot 43, which is a space for accommodating the stator winding 5. Here, one stator winding 5 is wound around each stator salient pole 42, and in FIG. 2, adjacent stator salient poles 42 in one slot 43. The stator windings 5 used in the above are arranged respectively.

  On the other hand, the rotor 3 is fixedly provided on the shaft 10, the non-magnetic ring 9 such as stainless steel disposed on the outer peripheral surface of the shaft 10, and the outer peripheral surface of the non-magnetic ring 9. A unit rotor core (hereinafter simply referred to as a rotor core) 7 to be formed and a permanent magnet 6 disposed between a pair of adjacent rotor cores 7 are formed. The rotor 3 is pivotally supported by a bearing (not shown) and is rotatably arranged on the inner periphery of the stator 2 via a radial air gap G. Here, the permanent magnets 6 and the rotor cores 7 are radially arranged at a predetermined angular pitch toward the outer periphery of the rotor 2.

  The rotor core 7 is configured by laminating electromagnetic steel plates punched by a punching die or the like, separated for each pole, and arranged side by side at a predetermined angular pitch along the circumferential direction of the rotor 3, The outer end of the rotor core 7 functions as a rotor magnetic pole 71 that constitutes the rotor magnetic path.

  Further, a permanent magnet 6 made of, for example, a ferrite magnet is accommodated in a space formed by a pair of adjacent rotor cores 7 and a nonmagnetic spacer 75, that is, a magnet insertion space 74. At this time, the magnetization of the permanent magnet 6 is perpendicular to the radial direction of the rotor 3, and the rotor core 7 alternates with NSNS along the circumferential direction of the rotor 3. Are arranged as follows. These permanent magnets 6 are fixed to the magnet insertion space 74 with an adhesive such as an epoxy resin. The nonmagnetic ring 9 and the nonmagnetic spacer 75 are provided in order to reduce the leakage magnetic flux to the inner peripheral side and the outer peripheral side of the rotor core 7.

  When a current is passed through the stator winding 5 of the fixed core 2, a rotational force is generated in the rotor core 7, and torque acting on the rotor core 7 is transmitted to the rotary shaft 10 via the nonmagnetic ring 9. . A space may be provided instead of the non-magnetic ring 9. In this case, a pair of disks are provided opposite to the axial ends of the rotating shaft 10, and the rotor core 7 is fastened to the disks with bolts, and torque acting on the rotor core 7 is transmitted to the rotating shaft 10. It is necessary.

  In this embodiment, the shape of the rotary iron core 7 is characteristic. As shown in FIG. 2, the permanent magnet 6 is disposed on both sides of the single rotor core 7, and the tip of the magnetic pole 71 of the rotor core 7 protrudes from the outer peripheral end of the permanent magnet 6.

  One surface of the protruding portion is formed with a flat surface portion 73 extending to the outer peripheral side as the same surface as the surface with which one permanent magnet 6 is in contact. In addition, the other surface of the protruding portion is a protrusion that extends and protrudes in the circumferential direction so as to cover a part of the outer peripheral portion of the other permanent magnet 6 with respect to the surface with which the other permanent magnet 6 is in contact. 72 is formed.

  In this embodiment, the rotor 3 is separated into two layers as shown in FIG. 5 as two rotors 3 in the axial direction of the rotary shaft 10 in order to reduce the pulsation of cogging torque. ing. The protruding direction of the protruding portion 72 provided on the rotor core 7 forming one rotor 3 and the protruding direction of the protruding portion 72 provided on the rotor core 7 forming the other rotor 3 extend in opposite directions. Is formed. Note that the top corner portion of the protrusion 72 of the rotor core 7 is rounded by beveling (chamfering) 77. The beveling 77 has a function of reducing torque pulsation by reducing the spatial harmonic component of the magnetic flux density in the air gap G.

  As described above, the rotor core 7 according to the present embodiment is simply formed by stacking the electromagnetic steel plates having the above-described protrusion 72 and flat portion 73 punched by a punching die or the like, and thus suppresses an increase in manufacturing cost. It is possible. In addition, in this embodiment, the two-layer rotor 3 is required, but the other rotor 3 can be used by turning the rotor core 7 upside down. Can do. A method for reducing torque pulsation (cogging torque) and its effect will be described later with reference to FIGS.

  Next, a more detailed configuration of the rotor core 7 according to the present embodiment will be described with reference to FIGS. In FIG. 3, the rotor core 7 is asymmetric so that the rotor core 7 becomes asymmetrical with respect to a reference line AA extending from the rotation center of the rotary shaft 10 so as to pass through the midpoint in the circumferential direction of the rotor core 7. One side of the magnetic pole 71 has a protrusion 72 extending in the circumferential direction.

  That is, the protrusion 72 extends in the circumferential direction so as to cover a part on the outer peripheral side of the permanent magnet 6 with respect to the surface where the rotor core 7 and the permanent magnet 6 come into contact. The amount of protrusion of the protrusion 62 is determined in a range that does not exceed the circumferential center line OO of the permanent magnet 6 when viewed from the reference line AA. A preferable value in this range will be described later. On the other hand, on the opposite side of the projecting portion 72, a flat surface portion 73 extending to the outer peripheral side is formed as the same surface as the surface with which the permanent magnet 6 is in contact.

  Here, the reference line AA is a magnetic pole pitch τp (= 2π / P, P: a center line OO drawn from the center of the rotating shaft 10 toward a position P that is half the magnetization direction thickness of the permanent magnet 6. This is equivalent to rotating in the rotation direction at an angle (τp / 2) of ½ of the number of magnetic poles).

  Further, it has been stated that the protrusion amount of the protrusion 72 is determined in a range not exceeding the circumferential center line OO of the permanent magnet 6 when viewed from the reference line AA. A more appropriate value will be described. As shown in FIG. 4, the angle a is a half of the magnetic pole pitch angle (the opening angle between the two permanent magnets 6 sandwiching the rotor core 7) when viewed from the reference line AA, and the reference line A- Assuming that the opening angle of the tip of the protruding portion 72 as viewed from A is an angle b and the opening angle of the root (contact surface with the permanent magnet) of the protruding portion 72 as viewed from the reference line AA is an angle c, (1) It is desirable to satisfy the conditions of b / a≈0.75 and (2) c / b≈0.71.

  Next, a method for reducing torque pulsation (cogging torque) and its effect will be described with reference to FIGS.

  In FIG. 5, in one rotor 3, the protrusion 72 a extends in the rotation direction (clockwise direction) of the rotor 3 so that the shape of the rotor core 7 changes in the axial direction of the rotation shaft 10. In the other rotor core 7 a and the other rotor 3, the second rotor core 7 b in which the protrusion 72 b extends in the direction opposite to the rotation direction of the rotor 3 (counterclockwise direction) is in the axial direction of the rotary shaft 10. Are stacked. A magnetic pole 71a and a magnetic pole 71b are formed on the rotor core 7a and the rotor core 7b, respectively. Further, the axial thicknesses of the rotor core 7a and the rotor core 7b are determined to be substantially the same. What is important is that the permanent magnet 6 is commonly used for the rotor core 7a and the rotor core 7b.

  By configuring the rotor 3 in this manner, the electrical angle phase difference corresponding to the electrical angle (the product of the mechanical angle and the number of pole pairs) of 30 degrees or the half period of the cogging torque is obtained at both axial ends of the rotor 3. It can be applied in the rotational direction, and the pulsating component of the cogging torque can be effectively canceled out.

  Further, the first rotor core 7a and the second rotor core 7b can be the same, that is, the first rotor core 7a can be used as the second rotor core 7b. Therefore, it is efficient because only one mold of the electromagnetic steel plate for producing the first rotor core 7a and the second rotor core 7b is required. Furthermore, since the permanent magnet 6 can be shared by the first rotor core 7a and the second rotor core 7b without dividing the permanent magnet 6 in the axial direction, it is possible to suppress an increase in manufacturing cost without increasing the number of parts. become.

  In addition, although the 1st rotor core 7a and the 2nd rotor core 7b showed what was laminated | stacked, the massive iron core which is not laminated | stacked can also be used. The rotating electrical machine applied in this case is suitable for a low-speed rotating type with little vortex loss, and a dust core or the like can be used as the bulk iron core.

  In order to show the effect of the present embodiment, the cogging torques of the permanent magnet rotating electric machine having the rotor 3 having the structure shown in FIG. 5 and the permanent magnet rotating electric machine having the rotor 3 having the conventional structure shown in FIG. 11 were compared. Here, as shown in FIG. 11, the rotor 3 has a pair of protrusions 72 formed in the entire axial direction in the circumferential direction of the magnetic pole 71 of the rotor core 7.

  FIG. 6 shows the simulation result of the cogging torque of the permanent magnet rotating electric machine, and FIG. 7 shows the result of Fourier series expansion of the cogging torque waveform. The cogging torque was calculated by magnetic field analysis using the edge element finite element method. As a calculation condition, torque is output when the rotor 3 is rotated from the outside at an electrical angle of 360 degrees (mechanical angle of 11.2 degrees). Since the permanent magnet rotating electric machine to be calculated has 64 magnetic poles and 48 salient poles, cogging torque is generated at 1/6 of the period of the induced voltage.

  From the calculation result of FIG. 6, since the period of the cogging torque is an electrical angle of 60 degrees, it can be said that this calculation result is approximately appropriate. By adopting the configuration as in the present embodiment, it can be seen that the cogging torque is greatly reduced in the permanent magnet rotating electrical machine according to the present embodiment compared to the conventional permanent magnet rotating electrical machine. In addition, as shown in FIG. 7, when the amplitudes of the respective orders are viewed, the sixth-order component that is the fundamental wave component of the cogging torque can be reduced to about ¼. From this, the usefulness of the permanent magnet rotary electric machine which becomes a present Example is clear.

  In the present embodiment described above, since the permanent magnet 6 of the rotor core 7a and the second rotor core 7b can be shared as shown in FIG. 5, an increase in the number of parts can be suppressed, and the manufacturing cost can be reduced. Can be planned.

  Further, as shown in FIG. 2, by applying beveling 77 to the magnetic pole 71 of the rotor core 7, the spatial harmonic component of the magnetic flux density in the air gap 8 can be reduced, and the torque pulsation can be reduced.

  Also, as shown in FIG. 3, by forming the magnetic pole 71 of the rotor 7 and bringing the protrusion 72 and the permanent magnet 6 into contact with each other, it is possible to prevent the permanent magnet 6 from being scattered by centrifugal force during rotation. It is possible to reduce the adhesive for fixing the permanent magnet 6 and the rotor core 7.

  Further, by making the first rotor core 7a and the second rotor core 7b of FIG. 5 into a lump core, the caulking operation of the core can be omitted, and the manufacturing cost can be reduced.

  To summarize this embodiment, the rotor core 7 may be formed by laminating magnetic steel plates having a projecting portion 72 and a flat surface portion 73 and using the same shape of the rotating cores 7a and 7b. It is possible to suppress an increase in cost.

  Further, by attaching the electromagnetic steel plates having the projecting portion 72 and the flat portion 73 in the opposite direction to form two layers of rotating iron cores 7a and 7b, the electrical angle is 30 degrees at both ends in the axial direction of the rotor 3 or cogging torque. Thus, the phase difference of the electrical angle corresponding to the half cycle can be applied in the rotation direction, and the pulsating component of the cogging torque can be effectively canceled out.

  Thus, according to the present embodiment, it is possible to provide a permanent magnet rotating electrical machine having a structure that realizes high torque density and low torque pulsation while suppressing an increase in manufacturing cost.

  Next, the configuration of the permanent magnet rotating electric machine according to the second embodiment of the present invention will be described with reference to FIG. In FIG. 8, the rotor core 7 is composed of a first rotor core 7a, a second rotor core 7b, a third rotor core 7c, and a fourth rotor core 7d, each of which has four layers. It is superimposed on.

  In FIG. 8, the protrusion 72 a of the lowermost rotor core 7 a and the protrusion 72 d of the uppermost rotor core 7 d protrude in a direction that coincides with the rotation direction of the rotor 3, and the rotation located therebetween. The protrusion 72b of the core 6b and the protrusion 72c of the rotor core 7c protrude in the direction opposite to the rotation direction of the rotor 3.

  With such a configuration, the rotational torque of the rotor 3 can be increased, and the magnetic pole 71 of the rotor 7 is coupled so that the shape of the magnetic pole 71 is bilaterally symmetrical with respect to the coupling surface, thereby acting on the rotor 3. The thrust force to be reduced can be reduced. Thereby, the burden at the time of manufacture can be eased. In addition, as a method of connecting the rotor 3 having such a structure, there are a method in which a bolt hole is formed in the rotor core and the shaft is fastened in the axial direction by a bolt, or a dovetail (ant connection) formed in the rotor core 7. There is a method of fixing and fastening with the non-magnetic ring 9 on the circumferential side. Which fixing method is adopted may be appropriately selected depending on the specifications of the permanent magnet rotating electric machine.

  Next, the configuration of the permanent magnet rotating electric machine according to the third embodiment of the present invention will be described with reference to FIG. 9. In this embodiment, the fixing method of the rotor core 7, the non-magnetic ring 9, and the fixed iron core 4 are described. A fixing method is proposed.

  In FIG. 9, the rotor core 7 is fixed to the nonmagnetic ring 9 by axially fitting a dovetail 76 of the rotor core 7 into a dovetail slot 91 on the outer peripheral side of the nonmagnetic ring 9. As a result, the torque acting on the rotor magnetic pole 71 can be efficiently transmitted to the nonmagnetic ring 9. Furthermore, by fixing the rotor core 7 to the non-magnetic ring 9 via the dovetail 76, the roundness on the outer diameter side of the rotor core 7 can be improved, so that the cogging torque generated due to manufacturing errors can be reduced. I can expect.

  Further, the non-magnetic ring 9 is provided with a bolt hole 92 for fitting the bolt 93. Thereby, the rotational torque transmitted to the nonmagnetic ring 9 can be transmitted to the outside by the bolt 93. Similarly, since reaction torque is generated in the stator core 4, a bolt hole 44 for fixing the stator core 4 to the outside with a bolt 45 is provided. As a result, the stator core 4 can be effectively prevented from moving due to the reaction torque. It is not necessary to fit the bolts 45 and 93 into all the bolt holes 44 and 92, and the number of bolts may be determined within a range in which the mechanical strength of the bolts 45 and 93 can be maintained.

  Next, the structure of the elevator drive hoisting machine using the permanent magnet rotating electric machine which becomes the 4th Embodiment of this invention is demonstrated based on FIG.

  In the elevator drive hoist 100, a fixed main shaft is formed at the center of the casing main body 101, and a sheave 102 is rotatably supported by a bearing 105 on the free end side of the fixed main shaft. In addition, electrical components such as a stator core 4 and a stator winding 5 that constitute an electric motor part are housed in an annular housing recess located on the outer peripheral side of the housing body 101. The stator core 4 is fixed to the housing body 101 by bolts 45.

  Further, as described above, the sheave housing 103 formed integrally with the sheave 102 via the bearing 105 is rotatably supported on the free end side of the fixed main shaft, and the sheave housing 103 is supported by the sheave 102 and the electric motor. It is comprised integrally with electric parts, such as the rotor core 7 which comprises a part. A nonmagnetic ring 9 fixed to the rotor core 7 is fixed to the sheave housing 103 by bolts 93, and the nonmagnetic ring 9 is press-fitted into the rotary shaft 10.

  As described above, the rotor core 7 is disposed opposite to the stator core 4 with a predetermined gap, and a plurality of permanent magnets 6 are fixed to the inner peripheral surface of the rotor core 7. Has been. Here, a brake drum 104 is integrally formed on the outer periphery of the sheave housing 103, and the brake drum 104 is configured to be braked by a brake device 106. The housing body 101 is provided with an encoder 107 that detects the rotation of the rotary shaft 10.

  Then, when a rotational force is generated in the rotor 3, it is transmitted to the sheave 102 via the sheave housing 103, and a plurality of main ropes wound around the sheave 102 are driven to raise and lower the car up and down. It will be. Although details of the brake device 104 are not shown in FIG. 10, when the car is moved up and down, the brake lining is separated from the rake drum 104 by a signal from a control device (not shown) to release the braking operation and When the car is stopped and its position is maintained, the brake lining is pressed against the brake drum 104 by a signal from the control device to apply a braking force to the brake drum 104 to perform a braking operation. In this embodiment, a ferrite magnet of about 0.45 T is used at room temperature.

  In the elevator-driven hoisting machine configured as described above, the permanent magnet rotating electric machine described in the first embodiment is used, so that the rotor core 7 is formed by laminating electromagnetic steel plates each having a projecting portion 72 and a flat portion 73. Therefore, it is only necessary to use the rotating iron cores 7a and 7b having the same shape opposite to each other. Therefore, it is possible to suppress an increase in manufacturing cost, and an electrical steel sheet having a projecting portion 72 and a flat portion 73 is used. By mounting them oppositely to make two layers of rotating cores 7a and 7b, the electrical angle phase difference corresponding to a half cycle of the cogging torque or 30 degrees of electrical angle at the axial direction both ends of the rotor 3 is rotated. Because the pulsating component of cogging torque can be effectively canceled out, an elevator-driven hoisting machine that performs a smooth raising and lowering operation while suppressing an increase in manufacturing cost is provided. Door can be.

  As described above, according to the present invention, it is possible to provide a permanent magnet rotating electric machine having a structure for reducing torque pulsation while suppressing an increase in manufacturing cost, and further, thereby smoothing while suppressing an increase in manufacturing cost. It is possible to provide an elevator drive hoist capable of performing a simple lifting operation.

  In this embodiment, a permanent magnet rotating electric machine and an elevator drive hoist using the same are shown, but in addition to this, a permanent magnet that requires high torque density and low torque pulsation such as a servo system and electric power steering. Note that it can be applied to rotating electrical machines.

  DESCRIPTION OF SYMBOLS 1 ... Permanent magnet rotary electric machine, 2 ... Stator, 3 ... Rotor, 4 ... Stator iron core, 41 ... Stator core back, 42 ... Stator salient pole, 43 ... Slot, 44 ... Bolt hole, 45 ... Bolt, DESCRIPTION OF SYMBOLS 5 ... Stator winding, 6 ... Permanent magnet, 7 ... Rotor core, 9 ... Non-magnetic ring, 10 ... Shaft, 71 ... Rotor magnetic pole, 72a, 72b, 72c, 72d ... Projection part, 73 ... Plane part 74 ... Magnet insertion space, 75 ... Non-magnetic spacer, 76 ... Dovetail, 77 ... Beveling, 91 ... Dovetail slot, 92 ... Bolt hole, 93 ... Bolt, 100 ... Elevator drive hoisting machine, 101 ... Body body, DESCRIPTION OF SYMBOLS 102 ... Sheave, 103 ... Sheave housing, 104 ... Brake drum, 105 ... Bearing, 106 ... Brake device, 107 ... Encoder. G ... Air gap.

Claims (13)

A stator composed of a stator iron core formed by laminating electromagnetic steel plates having a plurality of salient poles projecting toward the radially inner periphery, and a stator winding wound around the salient poles, A rotor composed of a plurality of unit rotor cores laminated with magnetic steel plates, arranged on the inner peripheral side of the stator via an air gap, and a plurality of permanent magnets arranged so as to sandwich the unit rotor core. And in a permanent magnet rotating electrical machine comprising a rotating shaft fixed to the rotor,
The unit rotor core is provided with a protruding portion where the unit rotor core protrudes from the outer peripheral end of the permanent magnet, and one surface of the protruding portion is the same as the surface in contact with the permanent magnet. A flat portion extending to the side is formed, and the other surface of the protruding portion extends and protrudes in the circumferential direction so as to cover a part of the outer peripheral portion of the permanent magnet with respect to the surface in contact with the permanent magnet A permanent magnet rotating electrical machine, wherein a protrusion is formed. In the permanent magnet rotating electric machine according to claim 1,
The permanent magnet rotating electric machine, wherein the permanent magnet is a ferrite magnet. In the permanent magnet rotating electric machine according to claim 1 or 2,
The rotor is separated into at least two layers in the axial direction of the rotary shaft, the projecting portion of the unit rotor core constituting one rotor, and the unit rotor core constituting the other rotor. The permanent magnet rotating electrical machine according to claim 1, wherein a protruding direction of the protruding portion protrudes in a reverse direction in a circumferential direction of the rotor. In the permanent magnet rotating electric machine according to claim 3,
The permanent magnet rotation combined with the unit rotor core constituting the one rotor and the unit rotor core constituting the other rotor is commonly used. Electric. In the permanent magnet rotating electric machine according to claim 3,
The unit rotor core constituting the one rotor and the unit rotor core constituting the other rotor have the same shape, and the unit rotor core used for the one rotor The unit rotor core used for the other rotor is turned over and used. In the permanent magnet rotating electric machine according to any one of claims 1 to 5,
The permanent magnet rotating electrical machine according to claim 1, wherein a protrusion amount of the protrusion formed on the unit rotor core is not more than half of a circumferential length of the permanent magnet from which the protrusion extends. The permanent magnet rotating electric machine according to claim 6,
The amount of protrusion of the unit rotor core is an angle a that is a half of the magnetic pole pitch angle when viewed from a reference line A-A connecting a center point in the circumferential direction of the unit rotor core and the center of the rotary shaft. The opening angle of the tip of the protruding portion when viewed from the line AA is an angle b, and the opening angle of the base of the protruding portion 72 (the contact surface with the permanent magnet) is the angle c when viewed from the reference line AA. In this case, the permanent magnet rotating electrical machine satisfies the conditions of b / a≈0.75 and c / b≈0.71. In the permanent magnet rotating electric machine according to claim 3,
The permanent magnet rotating electric machine, wherein the protrusion is in contact with the permanent magnet. In the permanent magnet rotating electric machine according to claim 3,
A permanent magnet rotating electrical machine characterized in that an upper surface corner portion on the tip end side of the protruding portion is beveled (chamfered) to be rounded. In the permanent magnet rotating electric machine according to claim 3,
The rotor is divided into four layers in the axial direction of the rotary shaft, and the projecting portion of the unit rotor core constituting the two rotors located at the outermost ends, and 2 located at the outermost ends. A permanent magnet rotating electrical machine characterized in that a protruding direction of the protruding portion of the unit rotor core constituting two rotors sandwiched between two rotors protrudes in the opposite direction in the circumferential direction of the rotor . In the permanent magnet rotating electric machine according to claim 3,
A permanent magnet rotating electrical machine characterized by using a bulk unit rotating core instead of the unit rotor core on which electromagnetic steel plates are laminated. In the permanent magnet rotating electric machine according to claim 3,
A non-magnetic ring is fixed between the rotor core and the rotary shaft. A dovetail slot is formed in the non-magnetic ring, and a dovetail formed in the unit rotor core is fitted in the dovetail slot. A permanent magnet rotating electrical machine, wherein the unit rotor core is fixed to a non-magnetic ring. A housing main body containing a stator and a stator winding, a fixed main shaft fixed on one side to the main body and the other as a free end, and rotatable on a free end side of the fixed main shaft via a bearing In an elevator drive hoisting machine comprising a sheave attached to which a main rope is wound, and a rotor that is formed integrally with the sheave and forms a motor part in cooperation with the stator,
An elevator-driven hoisting machine comprising the permanent magnet rotating electric machine according to any one of claims 1 to 12, wherein the electric motor section is formed.

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