JP2013090515A - Rotor of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure easy to be assembled, having good magnetic characteristics, and having strong holding power capable of withstanding acceleration of a rotor associated with improved characteristics of a rotary electric machine.SOLUTION: A rotor 8 of a rotary electric machine including a rotary core 20 in which steel plates are laminated, and permanent magnets 21 provided in the rotary core 20, comprises: magnet mounting recess grooves 25 provided in the rotary core 20 so as to be recessed from the outer periphery toward the inside, for mounting the permanent magnets 21; and magnet support members 22 for supporting the permanent magnets 21 existing in the magnet mounting recess grooves 25 from the outer periphery side. Fixing cores 23 are provided on both sides of the rotary core 21 in its axis direction.

Description

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

  For example, Patent Document 1 and Patent Document 2 describe a rotor of a rotating electrical machine including a permanent magnet. The rotor of the rotating electrical machine shown in Patent Documents 1 and 2 has a structure having a rotating core in which electromagnetic steel plates are laminated and a permanent magnet embedded in a magnet insertion hole formed in the rotating core.

  In recent years, electric motors equipped with such permanent magnets are often used in household appliances. In the washing and drying machine, a permanent magnet motor is used for driving the blower. Since the blower is required to blow at high speed and high pressure, the rotation speed of the motor reaches 10,000 to 20000 r / min. Also, permanent magnet motors are required to have high performance such as high efficiency and high output, and downsizing in accordance with the compactness of the product body.

Japanese Patent Application Laid-Open No. 9-219944 JP 2008-236866 A

  In a rotor of an electric motor (rotary electric machine) including a permanent magnet, a configuration in which a permanent magnet is embedded in an insertion hole provided in a rotating core as shown in Patent Documents 1 and 2 is often employed. A structure in which the permanent magnet is embedded in the insertion hole is suitable for withstanding the centrifugal force at high speed rotation.

  However, there are disadvantages in terms of magnetic properties and ease of assembly. In the assembly in which the permanent magnet is inserted into the insertion hole of the rotary core, it is necessary to prevent the sintered permanent magnet from being damaged (notched or broken). If the insertion hole is made large so that it can be easily inserted, a gap is formed between the permanent magnet and the insertion hole, and the flow of magnetic flux is deteriorated.

  Further, since the insertion hole in which the permanent magnet is embedded is closed at the outer periphery of the rotating core, the magnetic characteristics are deteriorated due to magnetic flux leakage. For example, when a ferrite permanent magnet is used as the permanent magnet, the magnetic permeability is lower than that of a neodymium permanent magnet, so that the influence of magnetic flux leakage becomes greater.

  In particular, when used in a blower of a washing / drying machine or the like, in order to rotate the electric motor at a high speed, a holding force of a permanent magnet that is not inferior to the centrifugal force of the rotor is also required.

  In view of the above problems, an object of the present invention is to provide a rotor of a rotating electrical machine that is easy to assemble and has good magnetic properties.

  The present invention relates to a rotor of a rotating machine including a rotating core in which steel plates are laminated and a permanent magnet provided on the rotating core, and a magnet for attaching the permanent magnet provided on the rotating core that is recessed inward from the outer periphery. It has a mounting groove and a magnet support member that supports the permanent magnet existing in the magnet mounting groove from the outer peripheral side, and a fixed core is provided at both axial ends of the rotating core.

  According to the present invention, the permanent magnet is mounted on the magnet mounting groove provided in the rotary core that is recessed inward from the outer periphery, and the permanent magnet is supported from the outer periphery by the magnet support member. easy. In addition, since the magnet support member is not connected to the rotating core via the permanent magnet, the magnetic flux leakage does not occur, the magnetic characteristics are improved, and the permanent magnet and the steel plate can be connected even when the rotating electrical machine is operated at high speed. The laminated magnet support members are firmly held.

It is sectional drawing of the air blower incorporating the electric motor (rotary electric machine) which concerns on this invention. 1 is a perspective view of a rotor of a rotating electrical machine according to an embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view showing an exploded rotor of a rotating electrical machine according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, the blower shown in FIG. 1 will be described. This blower is used in a drying device provided in a drum-type washing / drying machine, but can also be applied to a so-called vertical washing / drying machine that is not a drum type and a clothes drying machine that does not have a washing function. This type of drying apparatus requires high-speed and high-pressure air blowing, and the rotational speed of the electric motor reaches 10,000 to 20000 r / min. In addition to this, since there is little noise, high efficiency, high output, and miniaturization are required, a permanent magnet motor is often used as a drive source.

  The blower has an electric motor (rotary electric machine) 1 and a blower 2. The blower unit 2 includes a centrifugal fan 3 and a fan casing 4 in which the centrifugal fan 3 is accommodated. The fan casing 4 has a suction port 5 provided at a position facing the center of the centrifugal fan 3 and a discharge port 6 provided on the outer peripheral side of the fan casing 4. The centrifugal fan 3 is fixedly supported on the rotating shaft 7 of the electric motor (rotating electric machine) 1 and driven at a high speed rotation of 10,000 to 20000 r / min. By this high speed rotation, the air sucked from the suction port 5 is pressurized by the centrifugal fan 3 and blown vigorously from the discharge port 6.

  As shown in FIG. 1, the electric motor (rotating electric machine) 1 includes a rotor 8, a stator 9, housings 10 </ b> A and 10 </ b> B, and bearings 11 </ b> A and 11 </ b> B that rotatably support the rotating shaft 7. Here, the rotor 8 of the electric motor (rotating electric machine) 1 will be described with reference to FIGS.

  A rotor 8 of an electric motor (rotating electric machine) 1 includes a rotating core 20 in which steel plates such as electromagnetic steel plates are laminated, a permanent magnet 21, a magnet support member 22 in which steel plates such as electromagnetic steel plates are laminated, and a steel plate such as electromagnetic steel plates. It has the fixed core board 23 used. Here, the magnet support member 22 is separated from the rotary core 20 via the permanent magnet 21. The rotary core 20 and the fixed core plate 23 have a shaft insertion hole 24 at the center, and the rotation shaft 7 is press-fitted into the shaft insertion hole 24. The rotating shaft 7 has a staking process on the outer periphery, and prevents the rotating core 20 and the rotating shaft 7 from rotating. The magnet support member 22 serves as a magnetic path to the stator 9 of the permanent magnet 21. The permanent magnet 21 is a ferrite permanent magnet using a low permeability material. You may use the neodymium permanent magnet of a high magnetic permeability material.

  Next, as shown in FIG. 3, the rotary core 20 has a magnet mounting groove 25 that is recessed inward from the outer periphery. The magnet mounting groove 25 has a V shape, but various shapes including a U shape and an arc shape can be adopted as long as the shape is narrowed inward from the outer peripheral side of the rotary core 20. The permanent magnet 21 has a V shape that fits into the magnet mounting groove 25, and the thickness is the same from the bottom to the tip, but can be changed.

  The magnet support member 22 has a V shape so as to be fitted to the outer peripheral side of the permanent magnet 21, but the outer periphery has an arc shape. The permanent magnet 21 may apply an adhesive (not shown) to the joint surface with the magnet mounting concave groove 25 and the joint surface with the magnet support member 22. Since the permanent magnet 21 is joined to the magnet mounting groove 25 and the magnet support member 22 without a gap, the flow of magnetic flux is improved.

  Since the magnet mounting groove 25 has a shape that narrows inward from the outer peripheral side of the rotary core 20, a simple assembly in which the permanent magnet 21 is fitted from the outer peripheral side of the rotary core 20 can be performed. Since the outer peripheral surface side of the permanent magnet 21 has a shape that narrows from the outer peripheral side to the inner side in the same manner as the magnet mounting groove 25, a simple assembly in which the magnet support member 22 is fitted from the outer peripheral side of the permanent magnet 21 can be performed. it can.

  Further, since this assembly is different from the assembly in which the permanent magnet is inserted into the insertion hole of the rotating core, there is no possibility that the permanent magnet will be damaged (not cut or broken).

  The fixed core plate 23 is provided on both axial ends of the rotary core 20 and in the middle in the axial direction, and sandwiches the rotary core 20, the magnet support member 22, and the permanent magnet 21 in the axial direction. Then, a steel support rod body (not shown) is inserted into the through holes 26A and 26B provided in the fixed core plate 23 and the magnet support member 22 so that the support rod body does not fall off at the outer end surface of the fixed core plate 23. Caulking the support rod.

  With such a configuration, the permanent magnet 21 is supported from the outer periphery by the magnet support member 22, and the magnet support member 22 is supported by the fixed core plate 23 by the support rod body, so that the permanent magnet 21 and the magnet support member 22 are the rotor 8. Is supported without being blown by the centrifugal force that rotates at a high speed of 10,000 to 20,000 r / min.

  In addition, the number of the fixed core plates 23 provided at both ends and in the middle of the rotor in the axial direction is arbitrary as required, and the insertion location and the number of insertions of the fixed core plates 23 provided in the middle are also optional as necessary.

  For this reason, magnetic flux leakage does not occur, magnetic characteristics are improved, and the performance of the motor is improved, so that it can withstand centrifugal force due to extension of the dimension of the rotor in the axial direction and further increase in the number of rotations of the rotor. It can be a structure.

  That is, unlike the electric motors described in Patent Documents 1 and 2, the outer peripheral sides of the both ends of the permanent magnet 21 have an open configuration that is not wrapped with laminated magnetic steel sheets, so that no magnetic flux leakage occurs and the low permeability material. It is possible to provide an electric motor having a rotor having a strong holding force that can withstand a centrifugal force caused by high-speed rotation even with a ferrite permanent magnet using a magnet.

  In the above embodiment, the size and shape of the fixed core plate provided at both axial ends and in the middle are the same as those of the rotating core, permanent magnet, and magnet support member. However, different shapes and sizes can be used. is there.

7 Rotating shaft 8 Rotor 20 Rotating core 21 Permanent magnet 22 Magnet support member 23 Fixed core plate 24 Shaft insertion hole 25 Magnet mounting concave grooves 26A, 26B Through hole 30 Core holding portion 31 Magnet supporting member holding portion

Claims (3)

  In a rotor of a rotating machine including a rotating core in which steel plates are laminated and a permanent magnet provided in the rotating core, a magnet mounting groove for attaching the permanent magnet provided in the rotating core that is recessed inward from the outer periphery. Rotation characterized by having a magnet support member for supporting the permanent magnet existing in the magnet mounting concave groove from the outer peripheral side, and provided with a fixed core for sandwiching the rotary core at both axial ends of the rotary core. Electric rotor. The rotor of the rotating electrical machine according to claim 1,
A rotor of a rotating electrical machine, wherein a fixed core is provided in the middle of the rotor in addition to both axial ends of the rotor core. The rotor of the rotating electrical machine according to claim 1,
A rotor for a rotating electrical machine having a plurality of other fixed cores between fixed cores provided at both axial ends of the rotary core.