JP2012023900A - Rotor of permanent magnetic type rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor structure for a rotor of a magnet embedded type rotary machine which is improved to reduce the number of component kinds and manufacturing cost.SOLUTION: A rotor of a permanent magnet type rotary machine has a permanent magnet 3 embedded into a lamination block 1 of a core plate 2 and an end plate 4 overlapped on both ends of the lamination block and fastened by a bolt 5 to be mounted on a rotor axis 6. The core plate is formed by punching a magnet insertion hole 2a, a rotor axis hole, a fastening bolt hole, and a keyway 2d on the periphery of the rotor axis hole. The lamination block 1 laminates the core plate 2 in the same direction based on the keyway 2d as a reference upon setting a relative gap angle θ in the peripheral direction between the keyway 2d of the core plate 2 and a center position of the magnetic insertion hole 2a, and core plates whose front and back sides are reversed from the core plate 2 of the lamination block are used as end plates 4 for preventing the magnet from slipping and provided on both ends of the lamination block 1 by overlapping them to be integrally fastened by the bolt.

Description

  The present invention relates to a rotor structure of a permanent magnet type rotating electrical machine.

  As a rotor of a permanent magnet type rotating electrical machine, a permanent magnet is embedded in a laminated block of disk-shaped core plates, and end plates are overlapped on both ends of the laminated block and bolted together, and then the rotor core assembly is assembled. A magnet-embedded rotor mounted on a rotor shaft is known (see, for example, Patent Document 1).

  Next, FIG. 4 shows a conventional structure of an example of a magnet-embedded rotor with 6 magnetic poles and no skew. 4 (a) to 4 (c), 1 is a laminated block of a rotor core in which a disk-shaped core plate 2 (magnetic steel plate) is laminated in the axial direction, 3 is a cubic permanent magnet embedded in the laminated block 1, Reference numeral 4 denotes an end plate which is stacked on both ends of the laminated block 1 to prevent the permanent magnet 3 from coming off, 5 is a fastening bolt for fastening the laminated block 1 and the end plate 4 together, 5a is a nut, 6 is a rotor shaft, and 7 is a rotation. A key (sink key) for coupling the child core assembly to the rotor shaft 6.

  Here, as shown in FIG. 4C, the core plate 2 has a magnet insertion hole 2a corresponding to the number of magnetic poles (six poles) on the basis of the center O of the disk, and a bolt hole 2b through which the four fastening bolts 5 are passed. A rotor shaft hole 2c through which the rotor shaft 6 passes, and a key groove 2d circumscribed on the circumference of the rotor shaft hole 2c are formed by punching. In addition, about the magnet insertion hole 2a, the hole corresponding to the external shape of the permanent magnet 3 is allocated along the outer periphery of the core plate 2 so that each side of a regular hexagon may be formed. The bolt holes 2b are drilled at four locations at 90 ° intervals with respect to the center O of the core plate 2.

  On the other hand, the end plate 4 for preventing the magnet from being removed, which is arranged at both ends of the core laminated block 1 and closes the end surface of the magnet insertion hole 2a, is made of a non-magnetic material such as brass, copper or stainless steel in order to prevent leakage flux of the permanent magnet 3. As a product, the end plate 4 itself does not form a magnetic path for leakage flux.

JP 2002-354722 A (FIGS. 3 and 4)

  In the above-described conventional rotor structure, the end plates 4 arranged at both ends of the core laminated block 1 are made of a nonmagnetic material such as stainless steel in order to prevent leakage flux of the permanent magnet 3. For this reason, the types of assembly parts are increased, and the production cost of the end plate is added to increase the product cost of the rotor.

  In addition, Patent Document 1 described above discloses a configuration in which the entire rotor core is resin-molded to prevent the permanent magnet from coming off, instead of using a non-magnetic end plate. In practice, it is difficult to reduce manufacturing costs, such as requiring resin molding equipment on the assembly line.

  The present invention has been made in view of the above points, and eliminates the need for an end plate made of a non-magnetic material in a conventional structure for the purpose of reducing the types of components and manufacturing costs, and instead of using a laminated component of a rotor core. A rotor of a permanent magnet-type rotating machine that has been improved so that a core plate can be used as an end plate to prevent the embedded magnet from falling off and to reduce leakage magnetic flux, and can easily cope with the formation of step skew. The purpose is to provide.

In order to achieve the above object, according to the present invention, a permanent magnet is embedded in a laminated block of a disk-shaped core plate, and end plates are overlapped on both ends of the laminated block and bolted together, and then a rotor shaft. A permanent magnet type rotor with a structure mounted on the core plate, in which a magnet insertion hole, a rotor shaft hole, a fastening bolt hole, and a key groove are punched on the periphery of the rotor shaft hole. ,
A relative displacement angle θ in the circumferential direction is set between the key groove of the core plate and the center position of the magnet insertion hole, and the laminated block is laminated with the core plates aligned in the same direction based on the key groove. In addition, at both ends of the laminated block, a core plate of the laminated block and a core plate reversed in the front and back directions are overlapped as an end plate for retaining the magnet, and bolted together (Claim 1).

  In the rotor core assembly structure, the laminated block of the core plate is divided into two blocks in the axial direction, one of the blocks is laminated with the core plate facing up, and the other block is laminated with the core plate facing down. Then, a step skew angle 2 × θ corresponding to the deviation angle θ of the core plate is formed between the blocks (claim 2).

  As described above, a core plate having a shape in which a relative displacement angle θ in the circumferential direction is set between the key groove and the center position of the magnet insertion hole is used as a laminated core component, and the core plate is front and back with reference to the key groove. When they are overlapped in the opposite direction, the magnet insertion holes cross each other obliquely by the deviation angle θ. Therefore, in the present invention, in a state where the permanent magnet is embedded in the laminated block of the core plate, the core plates that are opposite to each other are overlapped on both ends of the laminated block and are bolted together. As a result, the core plates disposed at both ends of the laminated block serve as a permanent magnet retaining end plate.

  As a result, the core plate, which is a laminated component of the rotor core, can be directly used as an end plate without disposing separate end plates made of non-magnetic material at both ends of the core laminated block as in the conventional structure. The permanent magnet embedded in the laminated block of the rotor core can be retained and retained, thereby reducing the types of components constituting the rotor and the manufacturing cost.

  In addition, since magnet insertion holes are formed in the core plate over almost the entire circumference, the magnet insertion holes are provided for core plates (electromagnetic steel plates) arranged at both ends of the laminated block as end plates. Becomes a gap in the magnetic path, and the leakage flux of the permanent magnet is reduced.

  Also, after dividing the core stack block into two blocks in the axial direction, one block is the core plate facing up, and the other block is stacked with the core plate facing down to assemble the rotor core. A step skew angle 2 × θ corresponding to the deviation angle θ is formed between the blocks, so that cogging torque and torque ripple of the permanent magnet type rotating machine can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the rotor concerning Example 1 of this invention, Comprising: (a) is sectional drawing of a rotor assembly along a rotor axial direction, (b), (c) is the arrow in (a), respectively. It is sectional drawing of view AA and BB. It is a figure showing the shape of the core plate in FIG. 1, Comprising: (a), (b) is a top view of the front and back of a core plate, respectively. It is a block diagram of the rotor concerning Example 2 of this invention, Comprising: (a) is sectional drawing of a rotor assembly along a rotor axial direction, (b), (c), (d), (e ) Are sectional views taken along arrows AA, BB, CC, and DD, respectively, in FIG. FIG. 2 is a conventional rotor configuration diagram of a magnet-embedded rotating electrical machine, where (a) is a cross-sectional view of the rotor assembly along the rotor axial direction, and (b) and (c) are arrows in FIG. It is sectional drawing of AA and BB.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on the examples shown in FIGS. In addition, in the figure of an Example, the same code | symbol is attached | subjected to the member corresponding to FIG. 4, and the description is abbreviate | omitted.

First, the rotor structure according to the first embodiment of the present invention will be described with reference to FIGS. 1A to 1C, taking a 6-pole, skew-free embedded rotor as in FIG. 4 as an example.
The rotor of the illustrated embodiment is basically the same as the conventional structure shown in FIG. 4, but the core plate 2 of the electromagnetic steel plate constituting the core laminated block 1 and the permanent magnet 3 are arranged at both ends of the laminated block 1. For the end plate 4 to be fixed, a magnet insertion hole 2a, a bolt hole 2b, a rotor shaft hole 2c, and a key groove 2d are formed by punching at the following positions.

  That is, in the core plate 2 of the embodiment shown in FIGS. 2 (a) and 2 (b), it passes through the key groove 2d from the center position P of the magnet insertion hole 2a formed by being assigned to the peripheral area of the plate and the center O of the plate 2. A predetermined deviation angle θ (for example, θ = 2.5 °) is set in the circumferential direction between the imaginary line in the radial direction. In the illustrated embodiment, the deviation angle θ is set clockwise in the face-up direction of the core plate 2 (see FIG. 2A) with the key groove 2d as a reference, and when the orientation of the core plate 2 is reversed. (See FIG. 2B.) The deviation angle θ is reversed in the counterclockwise direction. Accordingly, when the front-facing core plate in FIG. 2A and the back-facing core plate in FIG. 2B are overlapped with respect to the key groove 2d, the positions of the bolt hole 2b, the rotor shaft hole 2c, and the key groove 2d are as follows. However, the magnet insertion holes 2a cross each other at an angle.

  In order to assemble the rotor core of FIG. 1 by laminating the core plate 2, first, the plate surface of the core plate 2 is aligned face up (FIG. 2 (a)), and then the key shaft 2d or bolt A laminated block 1 is constructed by laminating the core plate 2 in the axial direction with the hole 2b as a reference, and in this laminated state, a rectangular parallelepiped permanent magnet 3 is inserted from the side into the laminated block 1 and embedded. In order to assemble the laminated block 1, for example, the core plate 2 is sequentially inserted and laminated in a rod-shaped jig standing in the bolt hole 2b, and the permanent magnet 3 is coated with an adhesive or the like to apply the magnet insertion hole 2a. To be loaded.

  Next, one or several core plates 2 are overlapped face down (see FIG. 2B) as end plates 4 for retaining the magnets at both ends of the core laminated block 1 in which the permanent magnets 3 are embedded. In this state, the fastening bolts 5 are fitted into the bolt holes 2b, and the nuts 5a are tightened to assemble the rotor core.

  In the assembled state of the rotor core, as shown in FIG. 1 (c), the permanent magnet 3 (see FIG. 1 (b)) embedded in the laminated block 1 is overlapped face down at both axial ends. Further, the magnet insertion holes 2a of the core plate 2 (see FIG. 2B) obliquely intersect to partially cover the permanent magnet 3 from the outside. Thereby, the permanent magnet 3 embedded in the laminated block 1 is prevented from coming off in the axial direction and is held in the embedded position.

  Next, the rotor shaft 6 is passed through the assembly of the rotor core temporarily assembled in the above process, and a key 7 (sink key) is inserted into the key groove 2d to be fixed to the rotor shaft 6. A method in which the rotor core assembly is shrink-fitted and fixed to the rotor shaft 6 without using the key 7 can also be employed.

  According to the assembly structure of the rotor described above, the end plate of the non-magnetic material used in the conventional structure of FIG. 4 is eliminated, and instead of the core plate 2 of the electromagnetic steel sheet, which is a laminated part of the core laminated block 1. By diverting and stacking face down, the permanent magnet 3 embedded in the core laminated block 1 can be retained and retained, thereby reducing the types of parts and the manufacturing cost compared to the conventional structure.

  In addition, in the magnetic steel plate core plate 2 disposed at both ends of the core laminated block 1 as the magnet retaining end plate 4, the magnet insertion hole 2 a formed in the peripheral area is directly used as a gap in the magnetic path. The magnetic flux leakage of the magnet 3 can be reduced, and good magnetic properties of the rotor core can be ensured.

  Next, as an application example of the first embodiment, the configuration of the second embodiment corresponding to claim 2 of the present invention will be described with reference to FIG. In FIG. 3, members corresponding to those in FIG.

  In the second embodiment, the rotor core is utilized by utilizing a circumferential relative shift angle θ (for example, θ = 2.5 °) set between the magnet insertion hole 2a and the key groove 2d of the core plate 2. A step skew is formed in the laminated block 1 to reduce cogging torque and torque ripple.

  That is, in FIGS. 3A to 3E, the laminated block 1 that is a laminated body of the core plates 2 is divided into two blocks 1A and 1B in the axial direction. Here, the block 1A stacks the core plate 2 face up (see FIG. 2A), and the block 1B stacks the core plate 2 face down (see FIG. 2B). And 1B are combined with the key groove 2d as a reference, and the permanent magnet 3 is inserted into the magnet insertion hole 2a of the core plate 2 for each of the blocks 1A and 1B. Further, at both ends of the laminated block 1, as described in the first embodiment, as the end plate 4 for preventing the permanent magnet 3 from coming off, the left side end face of the block 1A has a core plate 2 facing backward (see FIG. 2B). And the core plate 2 (see FIG. 2 (a)) facing each other on the right end surface of the block 1B, and then tightening them together with bolts 5 fitted into the bolt holes 2b. Configure the assembly.

  According to this core assembly, as shown in FIGS. 3B and 3C, the permanent magnet 3 loaded in the magnet insertion hole 2a of the block 1A and the permanent magnet 3 loaded in the magnet insertion hole 2a of the block 1B In between, a step skew angle 2 × θ corresponding to the above-described clockwise and counterclockwise shift angle θ is set. Further, the permanent magnet 3 embedded in the blocks 1A and 1B is reversely turned upside down as the end plate 4 of the laminated block 1 superimposed on the end faces of the blocks 1A and 1B, as shown in FIGS. 3 (d) and 3 (e). It is secured with a core plate.

  In Examples 1 and 2, the number of magnetic poles of the rotor is set to 6 and the relative deviation angle θ between the magnet insertion hole 2a of the core plate 2 and the key groove 2d is set to θ = 2.5 °. In Example 2, the step skew angle 2 × θ = 5 ° is formed, but the number of magnetic poles and the deviation angle θ are not limited to this.

1 Laminated block of rotor core.
1A, 1B Block section 2 Core plate 2a Magnet insertion hole 2b Fastening bolt hole 2c Rotor shaft hole 2d Key groove 3 Permanent magnet 4 End plate 5 Fastening bolt 6 Rotor shaft 7 Key θ Relative between magnet insertion hole / key groove Misalignment angle

Claims (2)

A rotor of a permanent magnet type rotating machine having a configuration in which a permanent magnet is embedded in a laminated block of a disk-shaped core plate, and end plates are overlapped on both ends of the laminated block and bolted together and mounted on a rotor shaft. In the core plate, a magnet insertion hole, a rotor shaft hole, a fastening bolt hole, and a key groove punched and formed on the circumference of the rotor shaft hole,
After setting the relative displacement angle θ in the circumferential direction between the key groove of the core plate and the center position of the magnet insertion hole, the stacked block stacks the core plate in the same direction based on the key groove, A permanent magnet type rotating machine characterized in that a core plate having a laminated block and a front and back opposite to each other is stacked and bolted integrally at both ends of the laminated block as an end plate for preventing a magnet from coming off. Rotor. The rotor according to claim 1, wherein the laminated block of the core plate is divided into two blocks in the axial direction, one of the blocks is laminated with the core plate facing up, and the other block is laminated with the core plate facing down. And a step skew angle 2 × θ corresponding to the shift angle θ of the core plate is formed between the blocks.