JP2009112179A - Permanent-magnet generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a permanent-magnet generator capable of easily positioning a permanent magnet without deteriorating the roundness of a flywheel. <P>SOLUTION: In the permanent-magnet generator, a plurality of first engagement sections 12 and second engagement sections 13 each having erectile pieces 16, 18 erected outwardly in the diameter direction through bending lines 15, 17 are formed on a side section 11 of a cylindrical magnet cover 8, the permanent magnet 3 is positioned to the magnet cover 8 such that its movement in the axial direction is regulated by a flange 10 formed at the periphery of the side section 11 and the first engagement section 12 formed as opposed to this flange 10, and that in the circumferential direction of the permanent magnet is regulated by a pair of the second engagement sections 13 formed as opposed to the circumferential direction of the side section 11. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a magnet generator that generates power by electromagnetic induction between a permanent magnet and a power generation coil by rotation of a flywheel.

As a conventional magnet generator, a bowl-shaped flywheel that rotates about an axis, a plurality of permanent magnets that are fixed to the inner peripheral wall surface of the flywheel and rotate with the flywheel, and the inner periphery of each permanent magnet 2. Description of the Related Art A magnet generator including a cylindrical magnet cover provided in close contact with a surface and fixing means for fixing the permanent magnet to the magnet cover is known (for example, see Patent Document 1).
In this magnet generator, a locking portion is formed on one peripheral edge of a cylindrical magnet cover, an intermittent flange is formed on the other peripheral edge, and the axial direction of the permanent magnet is formed by the locking and intermittent flange. Positioning has been made.

Further, as a magnet generator, there is known a magnet generator in which a plurality of protrusions protruding inwardly in a cylindrical portion of a flywheel are formed by pressing, and the permanent magnets are positioned in the circumferential direction by the protrusions. (For example, refer to Patent Document 2).
JP 2003-319586 A JP 2002-101630 A

In the magnet generator described in Patent Document 1, the axial positioning of the permanent magnet with respect to the magnet cover can be dealt with by adjusting the axial length of the locking portion. Is not taken.
When the protrusion described in Patent Document 2 is used as a means for positioning the permanent magnet in the circumferential direction, the protrusion is formed by pressing, and the roundness of the flywheel deteriorates. Therefore, there is a problem that the air gap between the permanent magnet and the power generation coil provided inside the flywheel cannot be reduced, and the power generation efficiency is lowered accordingly.

  An object of the present invention is to solve the above-described problems and to provide a magnet generator capable of easily positioning a permanent magnet without reducing the roundness of a flywheel. The purpose is to obtain.

  In the magnet generator according to the present invention, a bowl-shaped flywheel that rotates about an axis, a plurality of permanent magnets that are fixed to the inner peripheral wall surface of the flywheel and rotate with the flywheel, and each of the permanent magnets In a magnet generator including a cylindrical magnet cover provided in close contact with an inner peripheral surface and a fixing means for fixing the permanent magnet to the magnet cover, a side surface portion of the cylindrical magnet cover is provided. Are formed with a plurality of first locking portions and second locking portions each having standing pieces erected radially outward via a folding line, and the permanent magnet has a peripheral edge portion of the side surface portion. A pair of the flange formed on the side surface and the first locking portion formed to face the flange are restricted from moving in the axial direction and are formed to face the side surface portion in the circumferential direction. The second The stop portion, the circumferential movement is restricted, is positioned with respect to the magnet cover.

  According to the magnet generator in accordance with the present invention, the permanent magnets can be formed without reducing the roundness of the flywheel by the first and second engaging portions formed on the side surface portion of the magnet cover. Easy positioning with respect to the magnet cover ensures high power generation efficiency.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or equivalent members and parts will be described with the same reference numerals.

Embodiment 1 FIG.
1 is a front view showing a rotor 1 of a magnet generator according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1, and FIG. FIG.
The magnet generator includes a rotor 1 connected to an internal combustion engine, and a stator (not shown) attached to a fixing member (not shown) inside the rotor 1.
The rotor 1 includes a bowl-shaped flywheel 2 that rotates around an axis, a plurality of permanent magnets 3 that are fixed to the inner peripheral wall surface of the flywheel 2 and that rotate with the flywheel 2, and the permanent magnet 3 A cylindrical magnet cover 8 provided in close contact with each inner peripheral surface, and a resin material 9 as a fixing means for fixing the permanent magnet 3 to the magnet cover 8 are provided.

The flywheel 2 includes a cylindrical portion 4, a boss portion 5, and a bottom portion 6 that connects the boss portion 5 and the cylindrical portion 4. A plurality of ventilation holes 7 are formed in the bottom 6. The boss portion 5 is fixed to a rotating shaft (not shown) that is rotationally driven by the internal combustion engine, and the rotor 1 rotates about the axis C-C.
The permanent magnet 3 is fixed to the inner peripheral surface of the cylindrical portion 4 of the flywheel 2 around the axis AA at equal angular intervals. A plurality of permanent magnets 3 made of rare earth magnets and having a circular arc cross section are adjacent to each other and are magnetized in opposite polarities, and generate a magnetic field whose direction changes alternately in the space inside the permanent magnet 3. It is supposed to be.
The resin material 9 is filled in the gaps between the adjacent permanent magnets 3 at both ends in the axis AA direction of the permanent magnets 3. By this resin material 9, the flywheel 2, the plurality of permanent magnets 3, and the magnet cover 8 are integrated.

The magnet cover 8 has a flange 10 formed at one end of the cylindrical side surface portion 11. A first locking portion 12 is formed on the side surface portion 11 so as to face the flange 10. Moreover, the 2nd latching | locking part 13 is formed facing the circumferential direction. Window portions 14 are respectively formed on the side surface portions 11.
The 1st latching | locking part 12 is comprised by a pair of standing piece 16 which stood up radially outward via the folding line 15 extended along the axial direction.
The 2nd latching | locking part 13 is comprised by a pair of standing piece 18 which stood up on the radial direction outer side via the folding line 17 extended along the axial direction.
The first locking portion 12 restricts movement of the permanent magnet 3 in the axial direction, and the second locking portion 13 restricts movement of the permanent magnet 3 in the circumferential direction.

The magnet cover 8 is manufactured by the following procedure.
First, a non-magnetic steel plate such as stainless steel is punched into a predetermined shape with a press machine, and one end of the strip-shaped steel plate is bent at 90 degrees to form the flange 10.
Subsequently, a pair of cut surfaces A are formed on the steel plate corresponding to positions surrounding the arranged permanent magnets 3, and a cut surface B is formed across the center of the cut surface A.
Thereafter, the respective cut pieces are erected on the radially outer side by 90 degrees to form the first and second engaging portions 12 and 13 including the erected pieces 16 and 18.
Finally, the steel cover 8 is completed by rounding the steel plate into a cylindrical shape and joining both ends.

The rotor 1 is manufactured by the following procedure.
First, the plurality of permanent magnets 3 are respectively arranged on the side surface portion 11 of the magnet cover 8. At this time, the movement of the permanent magnet 3 in the axial direction is restricted by the flange 10 and the first locking portion 12, and the movement in the circumferential direction is restricted by the pair of second locking portions 13 that face each other. Thereby, positioning with respect to the side part 11 is made | formed.
Thereafter, the permanent magnet 3 is fitted to the flywheel 2 together with the magnet cover 8.
Finally, by insert molding, the resin material 9 is filled in the gaps between the adjacent permanent magnets 3 and both end portions in the axial direction of the permanent magnets 3, and the resin material 9 is cured, so that the flywheel 2, the permanent magnets 3 and the magnet cover 8 are integrated.

  In the magnet generator configured as described above, the flywheel 2 rotates in conjunction with the rotating shaft driven to rotate by the internal combustion engine, and an alternating magnetic field generated by the permanent magnet 3 at that time causes a stator generating coil (not shown). ) Generates power. The AC output at this time is rectified by a rectifying diode (not shown) and fed to a load such as an in-vehicle battery.

As described above, according to the magnet generator of this embodiment, the first locking portions each having the standing pieces 16 and 18 that are formed on the side surface portion of the magnet cover 8 and are erected outward in the radial direction. The permanent magnet 3 is restricted from moving in the axial direction and the circumferential direction by the 12 and the second locking portion 13. The first locking portion 12 and the second locking portion 13 that regulate and position the movement of the permanent magnet 3 with respect to the magnet cover 8 are both formed in the state of a strip-shaped steel plate, and then deformed into a cylindrical shape. Thus, the magnet cover 8 is formed.
In this manner, the circumferential positioning of the permanent magnet 3 of the rotor 1 is performed by the second locking portion 13 of the magnet cover 8, and the circumferential positioning is performed by the protrusion formed on the flywheel 2. In addition, the roundness of the flywheel 2 is improved as compared with the conventional one, and the power generation efficiency is improved.
The inventor of the present application compared the magnet generator of this embodiment with the conventional one, and it was confirmed that the inner diameter accuracy of the flywheel 2 is improved by about 0.2 mm and the power generation efficiency is improved by about 3%. It was.

  Further, the upright pieces 16 and 18 constituting the first locking portion 12 and the second locking portion 13 are simply formed by raising the steel plate radially outward.

Embodiment 2. FIG.
FIG. 4 is an overall perspective view showing the magnet cover 20 of the magnet generator according to the second embodiment.
In the magnet cover 20 of this embodiment, the standing pieces 16 and 18 have folding lines 15 and 17 extending along the circumferential direction, and the first locking portion 12 and the second locking portion 13 are respectively It is comprised by a pair of standing piece 16 and 18 which opposed in the axial direction.
Other configurations are the same as those of the first embodiment.

In this embodiment, the direction of the folding lines 15 and 17 of the magnet cover 20 extends in the circumferential direction, which is different from the magnet cover 8 of the first embodiment in which the direction of the folding line 15 extends in the axial direction.
When it is necessary to strongly support the axial load on the permanent magnet 3, the magnet cover 8 according to the first embodiment is suitable. When there is a need to strongly support the circumferential load on the permanent magnet 3, this implementation is performed. The magnet cover 20 of the form 2 is suitable.

Embodiment 3 FIG.
FIG. 5 is an overall perspective view showing a magnet cover 30 of the magnet generator according to the third embodiment.
In the magnet cover 30 of this embodiment, the pair of opposed upright pieces 18 have a “C” shape, and the first locking portion 12 and the second locking portion are matched to the trapezoidal permanent magnet 3. 13 is formed.
Other configurations are the same as those of the first embodiment.

  The magnet cover 30 of this embodiment forms the first locking portion 12 and the second locking portion 13 corresponding to the shape of the permanent magnet 3, so that the irregular shaped permanent magnet 3 can be It can be seen that it can be easily handled.

In each of the above-described embodiments, the first locking portion 12 and the second locking portion 13 are each composed of a pair of upright pieces 16 and 18; however, the upright pieces need not necessarily be formed in pairs. There is no property and each may be a single standing piece.
Moreover, although the permanent magnet comprised with the rare earth magnet as the permanent magnet 3 was demonstrated, a ferrite magnet may be sufficient.
Moreover, although the case where the resin material 9 was used as a fixing means for fixing the permanent magnet 3 to the magnet cover 8 was described, of course, the present invention is not limited to this. For example, an adhesive may be used as the fixing means. Good.

It is a front view which shows the rotor of the magnet generator of Embodiment 1 of this invention. It is arrow sectional drawing along the II-II line | wire of FIG. It is a whole perspective view which shows the magnet cover of FIG. It is a whole perspective view which shows the magnet cover of the magnet generator of Embodiment 2 of this invention. It is a whole perspective view which shows the magnet cover of the magnet generator of Embodiment 3 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Rotor, 2 Flywheel, 3 Permanent magnet, 8, 20, 30 Magnet cover, 9 Resin material, 10 Flange, 11 Side part, 12 1st latching part, 13 2nd latching part, 15, 17 Folded curve, 16, 18 Standing piece.

Claims (6)

A bowl-shaped flywheel that rotates about an axis;
A plurality of permanent magnets fixed to the inner peripheral wall surface of the flywheel and rotating together with the flywheel;
A cylindrical magnet cover provided in close contact with each inner peripheral surface of the permanent magnet;
In a magnet generator provided with a fixing means for fixing the permanent magnet to the magnet cover,
A plurality of first locking portions and second locking portions, each having a standing piece erected radially outward via a folding line, are formed on the side surface portion of the cylindrical magnet cover,
The permanent magnet is restricted in movement in the axial direction by a flange formed at a peripheral edge of the side surface portion and the first locking portion formed to face the flange, and on the side surface portion. A magnet generator characterized in that circumferential movement is restricted by a pair of second locking portions formed opposite to each other in the circumferential direction, and is positioned with respect to the magnet cover.   The magnet generator according to claim 1, wherein the upright piece has the folding line extending along the axial direction.   3. The magnet generator according to claim 2, wherein each of the first locking portion and the second locking portion is constituted by a pair of the upstanding pieces opposed to each other in the circumferential direction.   The magnet generator according to claim 1, wherein the upright piece has the folding line extending in a circumferential direction.   5. The magnet generator according to claim 4, wherein each of the first locking portion and the second locking portion is configured by a pair of the upstanding pieces facing each other in the axial direction.   The said fixing means is a resin material, The said flywheel, the said permanent magnet, and the magnet cover are integrated by insert molding by this resin material, The any one of Claims 1-5 characterized by the above-mentioned. The magnet generator described.

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