JP2008099445A - Inner rotor of rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To constitute the inner rotor of an AC generator having a variable output function such that generation efficiency is enhanced furthermore by reducing iron loss. <P>SOLUTION: The inner rotor 1 of an AC generator having a variable field function includes a rotor core 4 formed of a dust core having a recess 7 and a control magnetic pole 9 on the outer circumferential part, and a permanent magnet piece 3 attached to the recess, or constituted of a cylindrical holder 22, a rotor core 23 fitted to the outer circumferential surface of the holder, and a permanent magnet piece 24 and a control magnet piece 25 arranged alternately in the circumferential direction on the outer circumferential surface of the rotor core. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inner rotor used in a rotating electrical machine such as an AC generator having a variable output function.

2. Description of the Related Art Conventionally, there has been known an inner rotor type AC generator that includes an inner rotor using a permanent magnet and a stator provided with a field coil, and can adjust generated power by controlling energization to the field coil. In the inner rotor of this AC generator, a permanent magnet is magnetized with the same polarity, and the same number of iron pieces as control magnetic poles are arranged at positions adjacent to the permanent magnet (for example, see Patent Document 1). I want to be)
JP 2004-350414 A

  In such an inner rotor of an AC generator having a conventional variable output function, an iron piece and a core are mainly formed of an iron block, and when a high frequency alternating magnetic field is received, an eddy current is induced in the iron and a large iron It is difficult to increase power generation efficiency because of loss.

  The present invention has been devised to eliminate such disadvantages of the prior art, and its main purpose is to configure the inner rotor of a rotating electrical machine so as to further reduce the iron loss and further increase the efficiency. There is to do.

  In order to achieve such an object, the present invention provides an inner rotor 1 for use in a rotating electrical machine such as an AC generator having a variable field function, and has a recess 7 and a control magnetic pole 9 on the outer peripheral portion. The rotor core 4 formed in this manner and the permanent magnet piece 3 mounted in the recess (claim 1). In particular, the permanent magnet piece is a bonded magnet (Claim 2), and the control magnetic pole and the outer peripheral surface of the permanent magnet piece are covered with a thin cylindrical cover 13 (Claim 3).

  The present invention also provides an inner rotor 21 of a rotating electrical machine, a cylindrical holder 22, a rotor core 23 fitted on the outer peripheral surface of the holder, and a permanent magnet arranged alternately in the circumferential direction on the outer peripheral surface of the rotor core. It consists of the piece 24 and the control magnetic pole piece 25 (Claim 4). In this case, the rotor core and the control magnetic pole are made of a dust core, the permanent magnet piece is made of a bond magnet, and these are formed by a multicolor molding method (Claim 5). . Furthermore, the outer circumferential surface of the control magnetic pole and the permanent magnet piece is covered with a thin cylindrical cover 26 (Claim 6).

  According to the present invention configured as described above, the electrical resistance of the periphery of the permanent magnet piece and the control magnetic pole is increased, and the reduction of iron loss is realized. it can.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an inner rotor of an alternator constructed according to the present invention. FIG. 1B shows a right side surface thereof, and FIG. 1A shows a cross section taken along line A-A in FIG. The inner rotor 1 includes, for example, a rotor core 2 that is coupled to a crankshaft of an engine and is directly connected to a rotating shaft that rotates, and a plurality of (four in this embodiment) that are attached to the outer periphery of the rotor core 2 in the circumferential direction. ) A permanent magnet piece 3 is provided.

  The rotor core 1 is formed of a powder magnetic core obtained by kneading a ferromagnetic metal powder such as iron powder into a molten resin material, molding the mold, and thermosetting the resin, and is formed in a substantially cylindrical shape. The rotor core has a different diameter from the approximate center in the axial direction, and the right portion in FIG. 1 is formed to have a larger diameter than the left portion. A step surface 6 perpendicular to the axis of the rotor core 2 is formed between the left small diameter portion 4 and the right large diameter portion 5 in FIG.

  A permanent magnet mounting recess 7 is formed on the outer peripheral portion of the large-diameter portion 5 at a position that equally divides the circumference (four in this embodiment). Each permanent magnet mounting recess 7 does not penetrate to the right end surface in the axial direction of the rotor core 2, and therefore, a side wall 8 is provided on the right side of each permanent magnet mounting recess 7.

  A portion between the permanent magnet mounting recesses 7 in the rotor core 2 is configured as a control magnetic pole 9 for forming a field pole of the generator together with the permanent magnet piece 3 mounted in the recess 7. That is, the control magnetic poles 9 are the same number (four) as the permanent magnet pieces 3 attached to the permanent magnet mounting recess 7 and are arranged alternately with the permanent magnet pieces 3 in the circumferential direction of the rotor core 2.

  The permanent magnet piece 3 attached to the permanent magnet mounting recess 7 has a shape in which a flat plate-like body in the radial direction of the rotor core 2 is bent in an arc shape so as to form the same outer peripheral surface as the large diameter portion 5. For example, it is composed of a bonded magnet obtained by kneading a powder obtained by pulverizing a ferrite magnet or a neodymium magnet into a molten resin material and molding it. These permanent magnet pieces 3 are fixed to the permanent magnet mounting recesses 7 formed at equal intervals on the outer peripheral portion of the large diameter portion 5 of the rotor core 2 with the same magnetic poles, for example, using an adhesive.

  On the left side of the permanent magnet mounting recess 7, an annular holder cap 10 is fixed using, for example, a screw in a state where the annular holder cap 10 is fitted to the left small diameter portion 4 of the rotor core 2 and joined to the step surface 6. And each permanent magnet piece 3 is pinched | interposed between the side wall 8 of each permanent magnet mounting | wearing recessed part 7, and the holder cap 10, and the latching nail | claw 11 which protruded facing the outer peripheral side of the side wall 8 and the holder cap 10 was carried out. Each permanent magnet piece 3 is held on the rotor core 2 by 12.

  The outer peripheral surface of the permanent magnet piece 3 and the control magnetic pole 9 is a common peripheral surface, and the outer peripheral surface is made of a thin plate material such as aluminum, titanium, or stainless steel and having a high specific resistance in a cylindrical shape. The formed cover 13 is attached.

  In the present embodiment, the control magnetic poles 9 and the permanent magnet pieces 3 are set so that their angles are substantially the same, but this is not necessarily the same.

  According to the inner rotor 1 configured as described above, the electric resistance of the periphery of the permanent magnet piece 3 and the control magnetic pole 9 is increased, and the iron loss is reduced. Can play.

  FIG. 2 shows a second embodiment of the present invention. The inner rotor 21 according to the present embodiment is fitted with a rotor core 23 having a cylindrical surface on the inner peripheral side and an octagonal outer peripheral side on a holder 22 formed by cutting a steel ingot into a head-cylinder shape. The four permanent magnet pieces 24 and the control magnetic pole pieces 25 are alternately fixed to the outer peripheral surface forming the same, and aluminum, titanium are provided on the outer peripheral surfaces of the permanent magnet pieces 24 and the control magnetic pole piece 25 forming the same peripheral surface. A cover 26 formed in a cylindrical shape with a non-magnetic and high specific resistance thin plate material such as stainless steel is attached.

  In this case, the rotor core 23 is primarily molded with a dust core in a mold in which the holder 22 is set in advance, and then the permanent magnet piece 24 made of a bond magnet having the same outer peripheral surface is formed on the outer peripheral surface thereof. The control magnetic pole piece 25 made of a dust core is secondarily molded by a two-color molding method.

  A holder cap 28 having an annular flange 27 is fitted to the left end portion of the holder 22 protruding from the left side surface forming the same axial direction end surface of the rotor core 23, the permanent magnet piece 24, and the control magnetic pole piece 25, and the rotor core In the state where the annular flange 27 is joined to the left side surfaces of the permanent magnet piece 24, the permanent magnet piece 24, and the control magnetic pole piece 25, they are fixed using, for example, screws. The rotor core 23, the permanent magnet piece 24, and the control magnetic pole piece 25 are sandwiched between the left end surface of the enlarged head 29 of the holder 22 and the annular flange 27 of the holder cap 28, and the enlarged head 29 of the holder 22 and the holder cap The permanent magnet pieces 24 and the control magnetic pole pieces 25 are held by the holder 22 by the locking claws 30, 31 protruding so as to face the 28 annular flanges 27.

  According to the inner rotor 21 configured as described above, the electrical resistance of the periphery of the permanent magnet piece 24 and the control magnetic pole 25 is increased, and the reduction of iron loss is realized. be able to.

  In addition, this invention is equally applicable not only to an alternating current generator but to the rotor of an electric rotating machine.

The 1st Embodiment of the inner rotor by this invention is shown, (B) is a right view, (A) is sectional drawing which follows the AA line. The 2nd Embodiment of the inner rotor by this invention is shown, (B) is a right view, (A) is sectional drawing which follows the AA line.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner rotor 3 Permanent magnet piece 4 Rotor core 7 Recess 9 Control magnetic pole 13 Cover 21 Inner rotor 22 Holder 23 Rotor core 24 Permanent magnet piece 25 Control magnetic pole piece 26 Cover

Claims (6)

An inner rotor of a rotating electric machine,
The inner rotor has a recess and a control magnetic pole on the outer periphery, and a rotor core formed of a dust core;
An inner rotor of a rotating electrical machine comprising a permanent magnet piece mounted in the recess.   The inner rotor of a rotating electrical machine according to claim 1, wherein the permanent magnet piece is a bonded magnet.   The inner rotor of a rotating electrical machine according to claim 1 or 2, wherein an outer peripheral surface of the control magnetic pole and the permanent magnet piece is covered with a thin plate cylindrical cover. An inner rotor of a rotating electric machine,
The inner rotor is composed of a cylindrical holder, a rotor core fitted on the outer peripheral surface of the holder, permanent magnet pieces and control magnetic pole pieces alternately arranged in the circumferential direction on the outer peripheral surface of the rotor core. An inner rotor of a rotating electrical machine.   5. The inner rotor of a rotating electrical machine according to claim 4, wherein the rotor core and the control magnetic pole are made of a powder magnetic core, and the permanent magnet piece is made of a bonded magnet, and is formed by a multicolor molding method.   6. The inner rotor of a rotating electrical machine according to claim 4, wherein the outer peripheral surface of the control magnetic pole and the permanent magnet piece is covered with a thin cylindrical cover.

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