JPS6126460A - Permanent magnet rotor - Google Patents

Abstract

PURPOSE:To reduce the decrease in motor characteristics due to an eddy current by mounting a stationary material made of nonmagnetic material on the outer periphery of a permanent magnet so as to both secure and to protect the surface of the magnet, thereby preventing the motor from locking. CONSTITUTION:A plurality of permanent magnets 3 are disposed on the outer periphery of a yoke 2, secured by a bonding agent 4, a bonding agent 6 is formed on the outer periphery of the magnets 3, a stationary material 5 made of nonmagnetic metal is mounted thereon, and secured by curing the agent 6. The magnets 3 are rigidly secured to the yoke 2 by the agent 4 and the material 5, and an eddy current generated at the material 5 of nonmagnetic material 5 can be reduced since the linear or strip-shaped material 5 having the radial size of the section or the width size of several millimeters or less is wound.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to the structure of a permanent magnet rotor and a method of fixing permanent magnets, and in particular to a permanent magnet that is arranged around the outer periphery of a yoke and is suitable for a round variable speed motor. It is related to the rotor.

[Background of the invention]

Currently, ferrite magnets are used as permanent magnets, which are relatively inexpensive and have good magnetic properties, but these ferrite magnets have extremely weak mechanical strength and are particularly resistant to impact forces compared to steel, which is the material of the rotor of induction motors. It is inferior. For this reason, in practical use, there is a permanent magnet in which glass fiber impregnated with a thermosetting resin is wrapped around the outer periphery of the permanent magnet, as described in JP-A-57-177265. Additionally, there is a technique currently being implemented by the applicant in which permanent magnets are protected by a stainless steel cover. However, glass fibers are susceptible to the effects of refrigerant, oil, etc. coming into contact with the surface glass fibers in the compressor.
Due to the effects of high-speed rotation, the glass fibers on the resin surface peeled off, causing the problem that the motor would lock up. In addition, in stainless steel covers, the gap between the magnet and stator is wide and there is a lot of magnetic leakage.
Iron loss occurred due to eddy currents generated in stainless steel, resulting in poor motor characteristics.

[Purpose of the invention]

The present invention has been made to improve this point, and in order to both secure the permanent magnet and protect its surface, a fixing material such as non-magnetic metal is wrapped around the outer circumference of the permanent magnet to prevent the motor from locking and to prevent the motor from swirling. An object of the present invention is to provide a permanent magnet rotor in which deterioration of motor characteristics due to current is reduced.

[Summary of the invention]

The present invention is made by wrapping and fixing a linear or band-shaped fixing material made of insulated non-magnetic metal around the outer periphery of a permanent magnet arranged in a cylindrical shape.

This prevents the locking of the C1 motor from IF, reduces iron loss due to eddy magnetic currents generated in non-magnetic metals, and suppresses the influence on motor characteristics as much as possible.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a vertical I of a permanent magnet rotor according to an embodiment of the present invention.
A cross-sectional view is shown in FIG. 2, and a cross-sectional view taken along the line AA in FIG. 1 is shown in FIG. 1 is a /yaft, 2 is a yoke, 3 is a permanent magnet, 4 is an adhesive, 5 is a fixing material such as a non-magnetic metal, and 6 is an adhesive. That is, after placing a plurality of permanent magnets 6 on the outer peripheral surface of the yoke 2 and fixing the adhesive 4C, the adhesive 6 is provided on the outer peripheral surface of the permanent magnets, and the fixing material 5 made of non-magnetic metal is placed on top of the adhesive 6. It is wrapped, and the adhesive 6 is cured and fixed. Therefore, the plurality of permanent magnets 6 can be firmly fixed to the yoke 2 by the adhesive 4 and the fixing material 5, and the eddy current generated in the non-magnetic metal fixing material 5 is Linear wires whose size or width is several millimeters or less can be reduced because they are wrapped in a band-shaped fixing material.

In addition, in terms of production technology, there are covers wrapped with glass fiber impregnated with thermosetting resin that require conventional final outer circumferential processing, and stainless steel covers that require highly accurate outer circumferential and inner circumferential processing. In comparison, the present invention rotates a permanent magnet rotor, wraps a linear or band-shaped fixing material 5 with a uniform cross-section in the longitudinal direction, and then fixes the outer periphery by simply curing and fixing the adhesive. Due to the high surface accuracy, final periphery machining is not required, resulting in excellent productivity.

[Effects of the Invention] According to the present invention, a structure is provided in which a plurality of permanent magnets are arranged on the outer periphery of a yoke, and the permanent magnets are wrapped and fixed with a linear or band-shaped fixing material made of an insulated non-magnetic metal. Therefore, it is possible to obtain the effect that the plurality of permanent magnets are firmly fixed by the fixing material and not lock, and also to reduce iron loss due to eddy current generated in the fixing material.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a permanent magnet rotor showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line A-A in FIG. DESCRIPTION OF SYMBOLS 1...Shaft, 2...Yoke, 6...Permanent magnet, 4...Adhesive, 5...Fixing material made of non-magnetic metal, 6...Adhesive.

Claims (1)

[Claims] 1. A plurality of permanent magnets (3) are arranged on the outer periphery of a yoke (2) constituting a permanent magnet rotor, and the permanent magnets are fixed with a linear or strip-shaped fixing material (5) made of an insulated non-magnetic metal.
A permanent magnet rotor characterized in that the outer periphery of a permanent magnet rotor is wrapped and fixed using.