JP6101716B2 - Permanent magnet synchronous motor - Google Patents

Description

  The present invention relates to a permanent magnet type synchronous motor, and more particularly to a permanent magnet type synchronous motor suitable for an elevator hoist motor.

  A permanent magnet type synchronous motor uses a rotor having a structure in which a plurality of permanent magnets and a plurality of cores formed of a magnetic material and assembled in a non-contact manner are alternately arranged radially (for example, Patent Document 1). .

  In a rotor having such a structure, an air gap is provided between the cores to increase the magnetic resistance between the cores, so that each core is magnetically independent. It is necessary to prevent short circuit. Further, since the magnetic flux short-circuited between the cores is not converted into torque, in order to increase the torque efficiently, the cores need to be magnetically independent without contacting each other.

  However, it is difficult to integrate separate permanent magnets and cores and to connect them to a rotating shaft. Conventionally, for the purpose of simplifying the structure and improving manufacturability, the permanent magnet and core and connecting the rotating shaft In general, the entire rotor such as a component is integrated and fixed by a resin mold.

Special table 2003-533158 gazette

  Resin molds have problems such as low strength and short life compared to steel materials. For this reason, in order to realize a higher torque and a longer life of the motor, a strong and long-life integration / fixing method is required.

  In general, the permanent magnet is fixed to the core by a method that is strong and has a long life by being hooked on a protrusion provided at the tip of the core, but the fixing method of the core itself uses a resin. Therefore, the strength and life of the entire rotor are not improved.

  An object of the present invention is to provide a permanent magnet type synchronous motor including a rotor that is easy to assemble and has a high strength and a long life.

The present invention includes a stator and a rotor, and the rotor is configured by alternately arranging a plurality of permanent magnets and a plurality of cores in a radial pattern when viewed from the rotation center, and is formed at each of radial ends of the plurality of cores. In the permanent magnet type synchronous motor that restricts the radial movement of each of the plurality of permanent magnets by the protrusion protruding in the circumferential direction, the holding block is formed of a nonmagnetic metal material and configured in an annular shape, The plurality of cores are each held by the holding block so that the movement in the radial direction is restricted, and the holding block is divided in the circumferential direction, and each divided holding block divided in the circumferential direction has a circumferential direction. Each of the divided holding blocks is connected to an adjacent divided holding block at the end, and each divided holding block is fixed to the motor rotating shaft with a bolt .

  According to the present invention, it is possible to obtain a permanent magnet type synchronous motor including a rotor that is easy to assemble and has a high strength and a long life.

  Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

1 is an external view (front view) of an entire permanent magnet type synchronous motor according to an embodiment of the present invention. 1 is a partially enlarged view of the appearance of a permanent magnet type synchronous motor according to an embodiment of the present invention. The enlarged view of the core (pole piece) used for the rotor of the permanent-magnet-type synchronous motor of one Example of this invention. The enlarged view of the division | segmentation holding | maintenance block used for the rotor of the permanent-magnet-type synchronous motor of one Example of this invention. The partial enlarged view of the front section of the permanent magnet type synchronous motor of one example of the present invention. The side sectional view of the rotor of the permanent magnet type synchronous motor of one example of the present invention. The figure explaining the rotor incorporating procedure to the motor rotating shaft in the permanent magnet type synchronous motor of one Example of this invention. The elements on larger scale of the external appearance of the permanent-magnet-type synchronous motor of another Example of this invention. Side surface sectional drawing of the rotor of the permanent-magnet-type synchronous motor of another Example of this invention.

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

  A schematic structure of the permanent magnet type synchronous motor of this embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is an external view of the entire motor, and FIG. 2 is a partially enlarged view of FIG.

  The motor according to the present embodiment includes a rotor 20 fixed to the motor rotating shaft 15 and a stator 21 that is arranged to face the rotor 20 in the radial direction via an air gap. The motor of this embodiment is an inner rotor type permanent magnet synchronous motor in which the rotor 20 is disposed inside the stator 21.

  As shown in FIG. 2, the stator 21 includes a stator core 9, a coil 10, and an insulating material 11 formed of laminated electromagnetic steel sheets. The stator core 9 has a back yoke portion 7 and a tooth portion 8. The coil 10 is wound around the tooth portion 8 via an insulating material 11. In this embodiment, concentrated winding is performed by winding the coil 10 around each tooth portion 8, but distributed winding may be performed by winding the coil 10 across a plurality of teeth 8.

  As shown in FIG. 2, the rotor 20 mainly includes a permanent magnet 1, a core (pole piece) 2, a holding block 3, and a contact plate 4. In FIG. 2, the permanent magnet 1 etc. which are stored in the inside of the contact plate 4 and are not visible from the outside are illustrated by dotted lines.

  The plurality of permanent magnets 1 and the plurality of cores 2 are alternately arranged radially as viewed from the rotation center of the motor rotation shaft. The plurality of permanent magnets 1 are arranged such that the magnetization direction, that is, the directions of the N pole and the S pole are in the motor circumferential direction and the same pole faces each core (pole piece) 2. As a result, the core 2 is magnetized by the magnetic flux of the permanent magnet 1, and the magnetic pole at the tip of the core 2 viewed from the stator 21 is alternately arranged in the circumferential direction with the N pole and the S pole. Can be configured.

  The core 2 needs to be magnetized by the permanent magnet 1 and is formed of a magnetic material. In order to reduce iron loss such as eddy current loss and hysteresis loss, it is particularly preferable to use a laminated magnetic steel sheet or a dust core.

  Next, the rotor structure inside the backing plate 4 will be described in detail with reference to FIGS. FIG. 3 is an enlarged view of the core 2, FIG. 4 is an enlarged view of the holding block 3, and FIG. 5 is a partially enlarged view of the motor front cross section.

  As shown in FIG. 3, the core 2 is provided with a protrusion 2 b protruding in the circumferential direction at a distal end portion in the radial direction (a distal end portion on the stator side). As shown in FIG. 5, the movement of the permanent magnet 1 outward in the radial direction is restricted by the protrusion 2b. The core 2 is attached to the holding block 3 so that movement in the radial direction is restricted. The specific structure of attachment will be described later.

  The holding block 3 is formed of a nonmagnetic metal material and has an annular shape in order to prevent the magnetic flux from short-circuiting between the cores. In this embodiment, nonmagnetic austenitic stainless steel such as SUS304 (JIS standard) is used. As the nonmagnetic metal material, a nonmagnetic aluminum alloy or the like can also be used.

  In this embodiment, the holding block 3 is divided in the circumferential direction, and each divided holding block divided in the circumferential direction is connected to an adjacent divided holding block at the end in the circumferential direction to form an annular shape. It is configured as follows. In this embodiment, the holding blocks are divided so that the number of divided holding blocks 3 is the same as that of the cores 2. In the present embodiment, the divided holding blocks are connected as follows. That is, as shown in FIG. 4, each division holding block 3 has a protrusion 3 b at one circumferential end and a groove 3 c at the other circumferential end. The divided holding blocks are connected in the circumferential direction by inserting the projection 3b of the divided holding block into the groove 3c of the adjacent divided holding block. In addition, the connection by the protrusion 3b and the groove | channel 3c is connected in the state with a moderate clearance gap.

  As described above, the core 2 is attached to the holding block 3 so that the movement in the radial direction is restricted. In this embodiment, the core 2 is attached to the holding block 3 as follows. That is, as shown in FIG. 3, a protrusion 2 a that protrudes in the circumferential direction is formed at the base of the core 2 in the radial direction. On the other hand, as shown in FIG. 4, a groove 3 a is formed on the outer peripheral surface of the divided holding block 3. Then, the projection 2a of the core 2 and the groove 3a of the divided holding block are firmly fitted by a method such as shrink fitting, and the core 2 and the divided holding block 3 are integrated to form the core block 5. In this embodiment, a plurality of core blocks 5 in which one core 2 is fixed to one divided holding block 3 are formed.

  In the present embodiment, first, the core 2 and the divided holding block 3 are firmly integrated to form the core block 5, and then the plurality of core blocks 5 are moderately formed by the protrusions 3 b and the grooves 3 c provided on the divided holding block 3. The rotor core 6 is formed by connecting in the circumferential direction with a clearance. Since the holding block 3 is formed of a non-magnetic metal material, in this embodiment, the core 2 is integrated in the circumferential direction via the holding block 3 without being magnetically short-circuited.

  Next, a procedure for incorporating the rotor 20 into the motor rotating shaft 15 will be described with reference to FIGS. 6 and 7. FIG. 6 is a cross-sectional side view of the rotor after assembly of the rotor, and FIG. 7 is a diagram showing the assembly procedure. 6 and 7 only show a half on one side from the axis center.

  As shown in FIG. 7, the backing plate 4 a and the rotor core 6 are assembled into the motor rotating shaft 15 in this order with respect to the motor rotating shaft 15, and then the permanent magnet 1 is opened in an open space formed between two adjacent core blocks. The rotor 20 is inserted and finally the entire rotor 20 including the contact plate 4b is fixed to the motor rotating shaft 15 using a bolt 30 or the like. By assembling in this way, the state of FIG. 6 is obtained. In this embodiment, a screw is provided on the motor rotating shaft 15 into which the bolt 30 is inserted, and the bolt 30 and the motor rotating shaft 15 are fastened. However, the bolt 30 may be fastened using a nut. . Further, as will be described later, the axial dimensions of the permanent magnet 1 and the core 2 are the same as or smaller than the axial dimension of the holding block 3, so that the contact plate 4a and the permanent magnet 1 and An adhesive or a filler is provided between the core 2 and the core 2. These assembly operations are performed such that the axial direction is the vertical direction in order to facilitate the operations.

  The contact plate 4 (4a, 4b) is formed of a nonmagnetic metal material in the same manner as the holding block 3 in order to prevent the magnetic flux from short-circuiting between the cores. The contact plate 4 (4a, 4b) is formed so as to restrict the movement of the permanent magnet 1 in the axial direction, that is, to prevent the permanent magnet from protruding in the axial direction. It is attached.

  Here, the radius of curvature of the surface of the holding block 3 opposite to the groove 3 a, that is, the inner peripheral surface of the holding block 3 (fitting surface with the motor rotating shaft) 3 d is the radius of the motor rotating shaft 15. The value is the same or less. In other words, when the divided holding blocks are connected to form the rotor core, the inner diameter of the holding block is configured to be the same as or smaller than the outer dimension of the motor rotation shaft. Further, the inner diameter dimension of the contact plate 4 a is set to a value equal to or smaller than the outer diameter dimension of the motor rotating shaft 15. Therefore, the contact plate 4a and the rotor core 6 are assembled by being press-fitted into the motor rotating shaft 15 using a press device or the like. By having such a dimensional relationship, the connecting portion of the core block 5 (the projection 3b and the groove 3c of the divided holding block) is rattling from a state having an appropriate clearance due to the fitting pressure with the motor rotating shaft 15. No state. The core (pole piece) 2 can be easily positioned with respect to the motor rotation shaft 15 via the holding block 3. Further, the rotor core 6 can be incorporated in a state in which the contact plate 4a is fixed by fitting with the motor rotating shaft 15.

  Next, the insertion of the permanent magnet 1 into the rotor core 6 will be described. As described above, the core 2 has the protrusions 2b in the circumferential direction at the front end portion on the stator side, and the permanent magnet 1 is stored in an open space formed by two adjacent core blocks 5. In this embodiment, the outer dimension of the permanent magnet 1 as viewed from the axial direction is smaller than the dimension of the open space as viewed from the axial direction. In other words, the length from the outer peripheral surface of the holding block 3 to the inner peripheral side of the protrusion 2b and the circumferential length between the cores 2 are larger than the outer dimensions of the corresponding permanent magnet. Therefore, there is a gap near the outer surface of the permanent magnet 1. Since the motor torque and the attractive force with respect to the stator 21 act on the core 2, the core 2 is slightly deformed by them. When the permanent magnet 1 and the core 2 are in close contact with each other, there is a possibility that the permanent magnet 1 may be broken due to the deformation of the core 2, so that a gap is provided.

  In the present embodiment, the axial dimensions of the permanent magnet 1 and the core 2 are the same as or smaller than the axial dimension of the holding block 3. By setting it as such a dimensional relationship, the curvature of the abutting plate 4b and the crack of the permanent magnet 1 can be avoided. In order to reliably obtain these effects, it is desirable that there is a gap between the contact plate 4b, the permanent magnet 1 and the core 2.

  In this embodiment, as described above, the core 2 is firmly fixed to the holding block 3 formed of a nonmagnetic metal material such as austenitic stainless steel to form the core block 5, and the core block 5 is connected. The rotor core 6 is configured. By doing in this way, it is possible to prevent the magnet magnetic flux from short-circuiting between the cores, and to fix the core itself by a method having high strength and long life. That is, strength and life can be improved as compared with conventional resin molds.

  In the case of a conventional resin mold, it is necessary to temporarily position the permanent magnet 1 and the core 2 with a positioning device or jig, perform resin molding while maintaining the state, and finally remove the positioning device or jig. In this embodiment, the holding block 3 and the core 2 formed of a nonmagnetic metal material are firmly fixed to form the core block 5, and the core blocks 5 are connected to each other via the holding block 3 to form the rotor core 6. Since the rotor core 6 is fitted to the motor rotating shaft 15 together with the contact plate 4a, the permanent magnet 1 and the core (pole piece) 2 are interposed via the holding block 3 by press-fitting the rotor core 6 into the motor rotating shaft 15. Positioning is performed. Therefore, this process of incorporation also serves to position the permanent magnet 1 and the core 2. That is, if this embodiment is compared with the conventional one, the assembly is completed in this embodiment at the stage of temporary positioning by a conventional positioning device or jig.

  Therefore, according to the present embodiment, it is possible to obtain a permanent magnet type synchronous motor including a rotor that is easy to assemble and has high strength and long life.

  Further, in this embodiment, since the holding blocks 3 are divided into the same number as the cores 2, the material utilization rate is greatly increased compared to the case of using a ring-shaped nonmagnetic metal material having a single ring shape or a small number of divisions. The material can be improved.

  Since the permanent magnet type synchronous motor of this embodiment can realize a high-strength and long-life rotor, it can realize a high torque and a long life of the motor, and in particular, a high torque and a long life of the motor. Is suitable for an elevator hoist motor that requires

  In the above-described embodiment, the protruding portion 2a is formed on the core 2 side, the groove 3a is formed on the holding block side, and the core 2 and the holding block 3 are fixed. However, the groove portion is formed on the core 2 side. Then, a protrusion projecting in the circumferential direction may be formed on the holding block 3 side to fix the core 2 and the holding block 3.

Further, in the above embodiment, the holding block is configured by being divided into the same number as the core in the circumferential direction, with less split number be fixed a plurality of cores to one holding block good.

  Moreover, in the above-mentioned Example, although the contact plate 4 (4a, 4b) is shape | molded in the donut-shaped board, you may divide | segment into the circumferential direction.

  In the first embodiment, the present invention is applied to an inner rotor type permanent magnet synchronous motor. However, the present invention can also be applied to an outer rotor type permanent magnet synchronous motor.

  In this case, the holding block is located on the outer peripheral side, and a groove for firmly fixing the core is formed on the inner peripheral side of the holding block. In addition, a protrusion that fits firmly with the groove of the holding block is formed at the outer peripheral end of the core in the radial direction of the core, and the radial direction of the permanent magnet is formed on the inner peripheral side of the core in the radial direction (the tip of the stator side). A protrusion that restricts inward movement is formed. Others are basically the same as those in the first embodiment, and a description thereof will be omitted. In the present embodiment, the same effects as those of the first embodiment can be obtained.

  In the first embodiment, the outer diameter of the contact plate 4b is the same as that of the contact plate 4a. However, the purpose of the contact plate 4b is to prevent the permanent magnet 1 from protruding in the axial direction, as shown in FIGS. Further, the outer diameter may be smaller than that of the contact plate 4a. The contact plate 4a also has a function of preventing the tilt of the permanent magnet when the rotor is incorporated, so that it is necessary to make the length so that the permanent magnet does not tilt. Others are the same as in the first embodiment, and a description thereof will be omitted. In the present embodiment, the same effects as those of the first embodiment can be obtained.

  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. Moreover, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

DESCRIPTION OF SYMBOLS 1 ... Permanent magnet, 2 ... Core (pole piece), 2a, 2b ... Projection, 3 ... Holding block (divided holding block), 3a ... Groove, 3b ... Projection, 3c ... Groove, 3d ... surface (fitting surface with motor rotation shaft), 4, 4a, 4b ... backing plate, 5 ... core block, 6 ... rotor core, 7 ... back Yoke part, 8 ... teeth part, 9 ... stator core, 10 ... coil, 11 ... insulating material, 15 ... motor rotating shaft, 20 ... rotor, 21 ... stator, 30 ···bolt

Claims (8)

A stator and a rotor, wherein the rotor is configured by alternately arranging a plurality of permanent magnets and a plurality of cores in a radial pattern when viewed from the rotation center, and formed at peripheral ends of the plurality of cores, respectively. In the permanent magnet type synchronous motor that restricts the radial movement of each of the plurality of permanent magnets by a protrusion protruding in the direction,
A holding block formed of a non-magnetic metal material and configured in an annular shape,
Each of the plurality of cores is held by the holding block such that movement in the radial direction is restricted,
The holding block is configured to be divided in the circumferential direction, and each divided holding block divided in the circumferential direction is connected to each adjacent divided holding block at the circumferential end,
Each of the divided holding blocks is fixed to a motor rotating shaft using a bolt, and is a permanent magnet type synchronous motor. In the permanent magnet type synchronous motor according to claim 1,
A permanent-magnet-type synchronization characterized by having a backing plate that is formed of a non-magnetic metal material, is formed to restrict axial movement of the plurality of permanent magnets, and is attached to both axial sides of the holding block. motor. In the permanent magnet type synchronous motor according to claim 1 or 2,
The permanent magnet type synchronous motor is an inner rotor type permanent magnet type synchronous motor,
The protrusions for restricting the movement of the permanent magnet in the radial direction are provided at the radial tips of the plurality of cores;
Protrusions projecting in the circumferential direction are formed at the radial root portions of the plurality of cores,
A permanent magnet type synchronous motor, wherein the holding block is formed with a groove into which the protrusion formed at the base of the core is fitted. In the permanent magnet type synchronous motor according to any one of claims 1 to 3 ,
In the divided holding block divided in the circumferential direction, a protrusion is formed at one circumferential end, and a groove into which the protrusion formed in the adjacent divided holding block is inserted at the other circumferential end. A permanent-magnet synchronous motor characterized by being formed. In the permanent magnet type synchronous motor according to claim 4 ,
The holding block is divided so that the number of divided holding blocks is the same as the plurality of cores,
A plurality of core blocks in which one of the plurality of cores is fixed to one of the divided holding blocks,
The core blocks are connected by inserting the protrusions formed at the circumferential end portions of the divided holding blocks into the grooves formed at the circumferential end portions of the adjacent divided holding blocks. A permanent magnet type synchronous motor. In the permanent magnet type synchronous motor according to any one of claims 1 to 5 ,
The divided holding block is connected with a gap between the adjacent divided holding blocks,
The divided holding block has an inner diameter dimension of the connected divided holding blocks such that when the connected divided holding blocks are attached to the motor rotation shaft, the connecting portions of the divided holding blocks are free from rattling. Is configured to be equal to or less than the outer dimension of the motor rotation shaft. In the permanent magnet type synchronous motor according to any one of claims 1 to 6 ,
Each of the plurality of permanent magnets is stored in an open space formed by the plurality of cores and the holding block, and the outer dimensions of each of the plurality of permanent magnets viewed from the axial direction are viewed from the axial direction. A permanent-magnet synchronous motor characterized by being smaller than the size of the open space. In the permanent magnet type synchronous motor according to any one of claims 1 to 7 ,
The permanent magnet type synchronous motor characterized in that axial dimensions of the plurality of permanent magnets and the plurality of cores are equal to or smaller than the axial dimension of the holding block.

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