JP2017195690A - Rotor structure in outer rotor type multipolar generator - Google Patents

Abstract

An outer including a fixed stator and a rotor that is formed in a cylindrical shape coaxially surrounding the stator and is provided with a plurality of permanent magnets on an inner peripheral surface of a yoke made of a magnetic material connected to a drive shaft. In a rotor-type multipolar generator, a rotor structure is provided which facilitates centering of a yoke while reducing the weight.
A hub 20 connected to a drive shaft 14 and a cylindrical portion 21 having one end connected to the hub 20 are integrally formed of a nonmagnetic material, and a yoke 22A is fixed to an inner peripheral surface of the cylindrical portion 21. .
[Selection] Figure 1

Description

  The present invention includes a fixed stator, and a rotor which is formed in a cylindrical shape coaxially surrounding the stator and has a plurality of permanent magnets provided on an inner peripheral surface of a yoke made of a magnetic material connected to a drive shaft. The present invention relates to an outer rotor type multipolar generator provided, and more particularly to improvement of a rotor structure.

  Such an outer rotor type multipolar generator is already known from Patent Document 1 and the like, and in this case, an end wall member that is die-cast by a light alloy such as aluminum and connected to a drive shaft, for example, mild steel Thus, the rotor is configured by a yoke that is coaxially formed to cover the stator and has one end fixed to the outer periphery of the end wall member and a plurality of permanent magnets fixed to the inner periphery.

JP 2004-120848 A

  In what is disclosed in Patent Document 1 described above, a cylindrical yoke, which is a member different from the end wall member, is fixed to the end wall member connected to the drive shaft. It is difficult to “center” to match the central axis of the yoke. Therefore, if the end wall member and the yoke are integrally formed of soft iron, “centering” is facilitated. However, it is difficult to form the end wall member and the yoke integrally by drawing the soft iron, and the weight is increased. .

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a rotor structure in an outer rotor type multipolar generator that facilitates centering of a yoke while reducing the weight.

  In order to achieve the above object, the present invention provides a fixed stator and a plurality of magnetic material yokes that are formed in a cylindrical shape coaxially surrounding the stator and coupled to a drive shaft. In an outer rotor multipolar generator comprising a rotor provided with a permanent magnet, a hub connected to the drive shaft and a cylindrical portion having one end connected to the hub are integrally formed of a nonmagnetic material, and the cylinder The first feature is that the yoke is fixed to the inner peripheral surface of the portion.

  In addition to the configuration of the first feature, the second feature of the present invention is that the hub and the cylindrical portion are made of resin.

  The third feature of the present invention is that, in addition to the configuration of the first feature, the hub and the cylindrical portion are made of a light metal.

  The fourth feature of the present invention is that, in addition to the configuration of the first feature, the yoke is made of an iron pipe.

  In addition to the configuration of the first feature, the present invention has a fifth feature that the yoke is formed by winding a magnetic metal strip a plurality of times or only once.

  In addition to the configuration of the first feature, the present invention has a sixth feature that the yoke is formed by winding a magnetic metal strip in a spiral shape.

  In addition to the structure of the first feature, the present invention has a seventh feature that the yoke is formed by winding a magnetic metal wire in a spiral shape.

  Further, according to the present invention, in addition to any of the first to seventh features, the permanent magnet is a resin-bonded permanent magnet that is molded and bonded to the inner peripheral surface of the yoke by injection molding. It is characterized by.

  According to the above feature of the present invention, the hub connected to the drive shaft and the cylindrical portion provided with the cylindrical yoke on the inner peripheral surface are integrally formed of a non-magnetic material. It is easy to match the central axis of the inner peripheral surface of the cylindrical portion, and the yoke can be easily centered, and the thickness of the yoke can be reduced to reduce the weight of the rotor.

  In particular, according to the second feature, the hub and the cylindrical portion are made of resin, and particularly according to the third feature, the hub and the cylindrical portion are made of light metal, so that the rotor can be further reduced in weight.

  In particular, according to the configuration of the eighth feature, the resin-bonded permanent magnet to be injection-molded is molded and bonded to the inner peripheral surface of the yoke, so that the weight can be further reduced, and the center axis of the hub and the inner portion of the permanent magnet can be reduced. It is easy to match the central axis of the peripheral surface, and the centering of the yoke is facilitated, so that the permanent magnet can be easily assembled.

It is a longitudinal cross-sectional view of the outer rotor type | mold multipolar generator of 1st Embodiment. FIG. 2 is a sectional view taken along line 2-2 of FIG. It is a disassembled perspective view of a rotor. It is a longitudinal cross-sectional view which shows the injection molding apparatus of the resin bond permanent magnet. The second embodiment is shown, in which (a) is a longitudinal sectional view of a rotor and (b) is a perspective view of a yoke. The third embodiment is shown, in which (a) is a longitudinal sectional view of a rotor and (b) is a perspective view of a yoke. 4A and 4B show a fourth embodiment, in which FIG. 4A is a longitudinal sectional view of a rotor, and FIG. 4B is a perspective view of a yoke. 4A and 4B show a fourth embodiment, in which FIG. 4A is a longitudinal sectional view of a rotor, and FIG. 4B is a perspective view of a yoke.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  The first embodiment of the present invention will be described with reference to FIGS. 1 to 4. First, in FIG. 1, this outer rotor type multipolar generator is used as an engine generator, for example. 11 is provided with a stator 12 fixed to a hollow support portion 11 a provided on the rotor 11 and a rotor 13 covering the stator 12. Is fixed.

  Referring also to FIG. 2, the stator 12 includes a ring-shaped stator core 15 formed by laminating and joining a plurality of magnetic steel plates, a synthetic resin bobbin 16 attached to the stator core 15, and the bobbin. 16 and a coil 17 wound around 16.

  Substantially T-shaped salient poles 15a are provided at a plurality of locations spaced at equal intervals in the circumferential direction of the outer circumference of the stator core 15, and the bobbin 16 is connected to the tip of the salient pole 15a and the stator core 15. The stator core 15 is formed so as to expose a part of both end surfaces and the inner peripheral surface, and the coil 17 is wound around the bobbin 16 at a portion corresponding to the salient pole 15a.

  Insertion holes 18 are provided in the inner peripheral portion of the stator core 15 at a plurality of locations spaced in the circumferential direction of the stator core 15, and bolts 19 inserted through the insertion holes 18 are provided in the support portion 11a. The stator 12 is fixed to the support portion 11a by screwing and tightening.

  Referring also to FIG. 3, the rotor 13 includes a hub 20 connected to the crankshaft 14, a cylindrical portion 21 having one end integrally connected to the hub 20, and an inner peripheral surface of the cylindrical portion 21. A cylindrical yoke 22A to be fixed and a plurality of permanent magnets 23 provided on the inner peripheral surface of the yoke 22A.

  The hub 20 and the cylindrical portion 21 are integrally formed of a nonmagnetic material such as resin. The yoke 22A is formed in a cylindrical shape from a magnetic material. In the first embodiment, the yoke 22A, which is an iron pipe, is fixed to the inner peripheral surface of the cylindrical portion 21 by press fitting.

  The hub 20 has a cylindrical support tube portion 20a into which the end portion of the crankshaft 14 is inserted and fixed, a ring portion 20b coaxially surrounding the support tube portion 20a, and a radial shape from the support tube portion 20a. A plurality of, for example, four connecting portions 20c that extend and are continuously connected to the ring portion 20b are integrally formed, and the cylindrical portion 21 is coaxially and integrally connected to the ring portion 20b. .

  The support cylinder 20a has a coaxial mounting hole 24 having a small diameter end at the end opposite to the engine body 11, and the end of the crankshaft 14 has the mounting hole at the end. A taper portion 14a to be fitted to 24 is formed. Between the support cylinder part 20a and the taper part 14a of the crankshaft 14 fitted in the taper hole 24 of the support cylinder part 20a, the support cylinder part 20a, that is, the hub 20 is relatively located with respect to the crankshaft 14. A key 25 for preventing rotation is inserted, and a bolt 26 having an enlarged head portion 26a that comes into contact with and engages with the end surface of the support cylinder portion 20a opposite to the engine body 11 is connected to the crank. Screwed into the end of the shaft 14.

  The plurality of permanent magnets 23 are resin-bonded permanent magnets that are connected in series and integrated, and are polarized to the N pole and the S pole on the outer peripheral side and the inner peripheral side, and the polarity of the polarized poles is The poles adjacent to each other in the circumferential direction of the yoke 22A are mold-bonded to the inner peripheral surface of the yoke 22A so that the poles are different from the outer peripheral side and the inner peripheral side. Fixed and by a magnetic attractive force between the resin bonded magnet and the yoke).

  In the injection molding of the permanent magnet 23, as shown in FIG. 4, a mold device 27 and an injection machine 28 are used. The mold device 27 includes the first mold 29, the second mold 30 that sandwiches the yoke 22A between the first mold 29, and the radially inner side of the yoke 22A. A ring-shaped magnetizing magnet 31 mounted on the first mold 29, and the cavity 32 is formed by the cooperation of the first mold 29, the second mold 30, the yoke 22A and the magnetizing magnet 31. It is formed.

  In the second mold 30, a sprue 33 connected to the nozzle 28 a at the tip of the injection machine 28, a plurality of gates 34 communicating with the cavity 32, and a runner 35 connecting the gates 34 and the sprue 33 are formed. Is done. A powder material 36 in which magnetic powder is covered with a resin to be coated is heated and melted and injected from the injection machine 28. The sprue 33, the runner 35 and the nozzles 28a of the injection machine 28 are used. It is injected into the cavity 32 through the gate 34. The material 36 heated and melted is magnetized by the magnetizing magnet 31 simultaneously with the molding in the cavity 32, and the permanent magnet 23, which is a resin-bonded permanent magnet integrated in a ring shape, is formed on the inner periphery of the yoke 22A. Mold bonded to the surface.

  The yoke 22A, in which the permanent magnet 23 is molded and bonded to the inner peripheral surface in this way, is fixed to the inner peripheral surface of the cylindrical portion 21 by being press-fitted into the cylindrical portion 21 integrally connected to the hub 20. The

  Next, the operation of the first embodiment will be described. A hub 20 connected to the crankshaft 14 and a cylindrical portion 21 having one end connected to the hub 20 are integrally formed of a resin which is a nonmagnetic material. Since the yoke 22A is fixed to the inner peripheral surface of the cylindrical portion 21, it becomes easy to match the central axis of the hub 20 with the central axis of the inner peripheral surface of the cylindrical portion 21, and the yoke 22A is centered. Can be easy. Furthermore, the centering accuracy of the yoke 22A can be further improved by subjecting the taper-shaped mounting hole 24 of the support cylinder portion 20a of the hub 20 to additional cutting with reference to the central axis of the hub 20. . In addition, the thickness of the yoke 22A can be reduced, and the weight of the rotor 13 can be reduced due to the fact that the hub 20 and the cylindrical portion 21 are made of resin.

  Further, since the permanent magnet 23 fixed to the inner peripheral surface of the yoke 22A is a resin-bonded permanent magnet molded and bonded to the inner peripheral surface of the yoke 22A by injection molding, it has the same magnetomotive force as compared with the conventional ferrite magnet. It is possible to reduce the volume to be obtained, and it is possible to reduce the weight and facilitate the assembly of the permanent magnet 23.

  In the first embodiment described above, the resin-bonded permanent magnet formed by injection molding is molded on the inner peripheral surface of the yoke 22A before being fixed to the cylindrical portion 21, but the cylindrical portion integrated with the hub 20 is used. It is also possible to mold-bond a resin-bonded permanent magnet that is injection-molded to the inner peripheral surface of the yoke 22 </ b> A press-fitted into 21. Thereby, it becomes easy to match the center axis of the hub 20 with the center axis of the inner peripheral surface of the resin bonded magnet that is injection-molded on the inner peripheral surface of the yoke 22A, and centering can be facilitated.

  In the first embodiment described above, the hub 20 and the cylindrical portion 21 are integrally formed of resin. However, the hub 20 and the cylindrical portion 21 are made of a light alloy such as aluminum, magnesium, or titanium. However, the same effect can be achieved.

  As a second embodiment of the present invention, as shown in FIG. 5, the yoke 22B is formed by winding a magnetic metal strip 37 a plurality of times or only once (twice in this embodiment). May be configured.

  As a third embodiment of the present invention, as shown in FIG. 6, the yoke 22C may be configured such that a belt plate 38 made of magnetic metal is spirally wound. The yoke 22C may be formed by cutting the cylinder 38 into a necessary length as shown by a chain line in FIG.

  Further, as a fourth embodiment of the present invention, as shown in FIG. 7, the yoke 22D is configured such that a wire rod 39 made of a magnetic metal and having a rectangular cross section is spirally wound. In this case, the yoke 22D may be formed by cutting the wire 39 into a required length as shown by a chain line in FIG.

  Further, as a fifth embodiment of the present invention, as shown in FIG. 8, the yoke 22E is configured such that a wire 40 made of a magnetic metal and having a circular cross-sectional shape is spirally wound. In this case, the yoke 22E may be formed by cutting the wire 40 into a necessary length as shown by a chain line in FIG. Moreover, the yoke 22E is fixed to the inner peripheral surface of the cylindrical portion 21 by being screwed into the cylindrical portion 21, but a female screw may be formed in advance on the inner peripheral surface of the cylindrical portion 21 for the screwing. Then, the center axis of the yoke 22E can be matched with the center axis of the hub 20 with high accuracy by increasing the accuracy of the female screw. In addition, the screwing direction of the yoke 22E into the cylindrical portion 21 is preferably set in the direction opposite to the rotation direction of the hub 20 and the cylindrical portion 21, that is, the direction of rotation of the crankshaft 14. The yoke 22E is screwed by the cylindrical portion 21 according to the rotation, and the yoke 22E is securely fixed to the inner peripheral surface of the cylindrical portion 21.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible. For example, a plurality of permanent magnets are composed of a plurality of single magnets that are composed of ferrite, rare earth, or bonded magnets and have N-pole and S-pole magnetic poles, and these single-piece magnets are arranged on the inner peripheral surface of the yoke in the circumferential direction. The adjacent single magnets may be arranged so that the polarities of the adjacent single magnets are different on the inner peripheral side and the outer peripheral side.

DESCRIPTION OF SYMBOLS 12 ... Stator 13 ... Rotor 14 ... Crankshaft 20 which is a drive shaft ... Hub 21 ... Cylindrical part 22A, 22B, 22C, 22D, 22E ... Yoke 23 ... Permanent magnet 37, 38 ... strips 39, 40 ... wire rods

Claims (8)

  A fixed stator (12), and a yoke (22A, 22B, 22C, 22D, 22E) made of a magnetic material that is coaxially surrounded by the stator (12) and is connected to the drive shaft (14). ) Having a rotor (13) provided with a plurality of permanent magnets (23) on the inner peripheral surface thereof, a hub (20) connected to the drive shaft (14), and the hub A cylindrical part (21) having one end connected to (20) is integrally formed of a nonmagnetic material, and the yoke (22A to 22E) is fixed to an inner peripheral surface of the cylindrical part (21). The rotor structure in the outer rotor type multipolar generator.   The rotor structure in the outer rotor type multipolar generator according to claim 1, wherein the hub (20) and the cylindrical portion (21) are made of resin.   The rotor structure in the outer rotor type multipolar generator according to claim 1, wherein the hub (20) and the cylindrical portion (21) are made of light metal.   The rotor structure in an outer rotor type generator according to claim 1, wherein said yoke (22A) consists of an iron pipe.   The rotor structure in an outer rotor type multipolar generator according to claim 1, wherein the yoke (22B) is formed by winding a magnetic metal strip (37) a plurality of times or only once.   The rotor structure in an outer rotor type multipolar generator according to claim 1, wherein the yoke (22C) is formed by winding a magnetic metal strip (38) in a spiral shape.   The rotor structure in the outer rotor type multipolar generator according to claim 1, wherein the yoke (22D, 22E) is formed by winding a magnetic metal wire (39, 40) in a spiral shape.   The permanent magnet (23) is a resin-bonded permanent magnet that is molded and bonded to the inner peripheral surface of the yoke (22A to 22E) by injection molding. The rotor structure in the outer rotor type multipolar generator.

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