Rotor magnet, rotor, and rotor manufacturing method

Patent metadata

Field	Value
Publication number	US-9350219-B2
Application number	US-201113392353-A
Country	US
Kind code	B2
Filing date	Feb 14, 2011
Priority date	Feb 14, 2011
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

A purpose is to provide a rotor manufacturing method including a magnet assembly formed of divided permanent magnet pieces to enhance insulation and advance cost reduction. The rotor manufacturing method includes forming permanent magnet pieces by dividing a permanent magnet, arranging and resin-molding the permanent magnet pieces to form a magnet assembly, and placing the magnet assembly in a rotor. The method includes placing the permanent magnet pieces all together in a molding die for use in resin-molding, and moving the permanent magnet pieces by a moving device provided in the molding die to move the permanent magnet pieces within the molding die, thereby forming the magnet assembly.

First claim

The invention claimed is:

1. A method of manufacturing a rotor including: dividing a permanent magnet into a plurality of permanent magnet pieces; arranging and resin-molding the permanent magnet pieces to form a magnet assembly; and placing the magnet assembly in a rotor,
wherein the method comprises:
placing the permanent magnet pieces all together in a molding die for use in resin-molding; and
moving the permanent magnet pieces within the molding die by moving means for moving the permanent magnet pieces to form the magnet assembly, the moving means being provided in the molding die,
wherein the permanent magnet pieces are formed by splitting the permanent magnet,
the molding die is provided with a gate through which a resin for resin-molding flows in the molding die, and
the gate serves as the moving means,
wherein the gate includes a plurality of gates provided in the molding die,
the plurality of gates include a first gate provided in a surface of the die facing a side surface of a first permanent magnet piece of the permanent magnet pieces and a second gate provided on a surface of the die facing a side surface of a second permanent magnet piece located adjacent to the first permanent magnet piece,
the first gate and the second gate are provided in opposite surfaces of the molding die, and
after the permanent magnet pieces are placed in the molding die, the resin is supplied in the molding die through the first gate and the second gate to move the first permanent magnet piece and the second permanent magnet piece in opposite directions so that the permanent magnet pieces are resin-molded to form the magnet assembly.

2. The method of manufacturing a rotor according to claim 1 ,
wherein pins for supporting the side surfaces of the permanent magnet pieces are provided in the number corresponding to the number of the permanent magnet pieces to be placed in the molding die,
the pins include a first pin placed in a surface of the die facing a side surface of the first permanent magnet piece of the permanent magnet pieces and a second pin placed in a surface of the die facing a side surface of the second permanent magnet piece located adjacent to the first permanent magnet piece,
the first pin and the second pin are placed respectively in opposite surfaces of the molding die,
after the permanent magnet pieces are placed in the molding die, the first pin and the second pin are moved to positions short of the corresponding permanent magnet pieces,
the resin for resin-molding is supplied in the molding die to move the first permanent magnet piece into contact with the first pin and the second permanent magnet piece into contact with the second pin to form the magnet assembly.

3. A method of manufacturing a rotor including: dividing a permanent magnet into a plurality of permanent magnet pieces; arranging and resin-molding the permanent magnet pieces to form a magnet assembly; and placing the magnet assembly in a rotor,
wherein the method comprises:
placing the permanent magnet pieces all together in a molding die for use in resin-molding; and
moving the permanent magnet pieces within the molding die by moving means for moving the permanent magnet pieces to form the magnet assembly, the moving means being provided in the molding die,
wherein the permanent magnet pieces are formed by splitting the permanent magnet,
the molding die is provided with a gate through which a resin for resin-molding flows in the molding die, and
the gate serves as the moving means,
wherein pins for supporting the side surfaces of the permanent magnet pieces are provided in the number corresponding to the number of the permanent magnet pieces to be placed in the molding die,
the pins include a first pin placed in a surface of the die facing a side surface of the first permanent magnet piece of the permanent magnet pieces and a second pin placed in a surface of the die facing a side surface of the second permanent magnet piece located adjacent to the first permanent magnet piece,
the first pin and the second pin are placed respectively in opposite surfaces of the molding die,
after the permanent magnet pieces are placed in the molding die, the first pin and the second pin are moved to positions short of the corresponding permanent magnet pieces,
the resin for resin-molding is supplied in the molding die to move the first permanent magnet piece into contact with the first pin and the second permanent magnet piece into contact with the second pin to form the magnet assembly.

4. A method of manufacturing a rotor including: dividing a permanent magnet into a plurality of permanent magnet pieces; arranging and resin-molding the permanent magnet pieces to form a magnet assembly; and placing the magnet assembly in a rotor,
wherein the method comprises:
placing the permanent magnet pieces all together in a molding die for use in resin-molding; and
moving the permanent magnet pieces within the molding die by moving means for moving the permanent magnet pieces to form the magnet assembly, the moving means being provided in the molding die,
wherein the molding die is provided with a plurality of gates through which a resin for resin-molding flows in the molding die, the gates being the moving device,
the gates are located in one surface of the molding die and spaced at intervals corresponding to vicinities of mating surfaces of the adjacent permanent magnet pieces, and
after the permanent magnet pieces are placed in the molding die, the resin for use in resin-molding is supplied in the molding die to flow between the mating surfaces of the adjacent permanent magnet pieces to flow the magnet assembly.

5. A method of manufacturing a rotor including: dividing a permanent magnet into a plurality of permanent magnet pieces; arranging and resin-molding the permanent magnet pieces to form a magnet assembly; and placing the magnet assembly in a rotor,
wherein the method comprises:
placing the permanent magnet pieces all together in a molding die for use in resin-molding; and
moving the permanent magnet pieces within the molding die by moving means for moving the permanent magnet pieces to form the magnet assembly, the moving means being provided in the molding die,
wherein the molding die is provided with a movable die for moving the permanent magnet pieces as the moving device, the movable die being placed in an end of the permanent magnet pieces in a stack direction thereof,
a cavity defined by the molding die and the movable die is formed with a size larger than a final size of the magnet assembly in the stack direction of the permanent magnet pieces,
after the permanent magnet pieces are placed in the molding die, the permanent magnet pieces are moved by another moving device to widen intervals between the permanent magnet pieces, and
after the resin for resin-molding is supplied in the molding die,
the movable die is moved toward the placed permanent magnet pieces to reduce the cavity so that the magnet assembly is formed with a predetermined size.

Assignees

• Fukaya Tetsuyoshi
• Nishikuma Yasushi
• Toyota Motor Co Ltd

Inventors

• Fukaya Tetsuyoshi
• Nishikuma Yasushi

Classifications

• H01F41/0253

  for manufacturing permanent magnets · CPC title

• Y10T29/49012

  Rotor · CPC title

• H02K15/03 Primary

  having permanent magnets · CPC title

• H02K1/2766

  having a flux concentration effect · CPC title

• H02K1/27 Primary

  Rotor cores with permanent magnets · CPC title