JPH0314931Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] The invention relates to a rotor for a so-called portable self-excited generator, which is driven by a small engine and used for lighting at construction sites, etc. In order to improve the rise of the initial output voltage of the generator, there is a convex pole-shaped iron core that is stacked and fitted on the rotor shaft, a field coil wound around the core, and a convex pole part of the iron core. This invention relates to an improvement of a rotor consisting of a magnet fitted into a rotor.

[Conventional technology and problems]

Figure 1 is a perspective view showing a conventional rotor of this type;
The figure is a cross-sectional view showing the relationship between the rotor and the stator.The rotor 1 has an iron core 3, which is made by stacking a large number of punched iron plates formed in a convex pole shape, fitted onto the rotor shaft 2. The field coil 5 is wound around the coil winding portion 3A via the coil bobbin 4, and the iron core 3
It was customary to directly fit a radially magnetized dovetail magnet 6 into the dovetail groove 3C on the convex pole portion 3B.

When this rotor 1 is wound around the stator 7 of a self-excited generator and rotated as shown in FIG.
The magnetic flux φ ₁ of the magnet 6 flows as shown by the arrow,
As a result, the power generating coil 8 wound around the stator 7
This generates an initial output voltage.

However, as described above, this rotor 1 is made by directly inserting and fitting the dovetail magnets 6 into the dovetail grooves 3C provided in the convex pole portion 3B of the iron core 3. As shown, it does not flow to stator 7,
There is a drawback that a relatively large amount of so-called leakage magnetic flux φ ₀ flows, which lowers the initial output voltage of the generator coil 8, and the magnet 6 is formed by sintering and molding a material such as ferrite or rare earth material. Since it has extremely brittle properties, it often breaks when it is directly inserted into the groove 3C, resulting in an increase in manufacturing costs.

[Purpose and structure of the idea]

The present invention has been developed with special attention to the above points, and its purpose is to minimize the leakage magnetic flux of the magnets fitted to the convex poles of the rotor, thereby increasing the magnetic flux effective for power generation. To provide a rotor which can improve the rise characteristics of the initial output voltage of a generator by measuring the increase, and can almost completely prevent damage when assembling and fitting magnets, thereby reducing manufacturing costs. be.

In order to achieve the above object, the present invention uses a dovetail-shaped magnet whose front, rear, left, and right sides, excluding the top and bottom surfaces, are surrounded by synthetic resin protective covers in a dovetail-shaped concave groove provided on the convex pole part of a laminated iron core. It is characterized by being magnetized and fitted in the radial direction.

[Example of idea]

FIG. 3 is a perspective view of the main parts of a rotor according to an embodiment of the present invention;
4 and 5 are perspective views of the magnets and protective cover fitted to the rotor, and the rotor 11 of this embodiment has a large number of convex pole iron cores 13 laminated on the rotor shaft 12. The field coil 15 is wound around the coil winding portion 13A of the iron core 13 via the coil bobbin 14, and the groove 13C provided in the convex pole portion 13B of the iron core 13 is fitted in the radial direction. The rotor 1 is similar to the conventional rotor 1 shown in FIG. 1 in that it is equipped with a dovetail-shaped magnet 16, but the magnet 16 is integrally made of synthetic resin on its front, rear, left and right sides, excluding the top and bottom surfaces. It is surrounded by a protective cover 19 formed as shown in the figure.

Therefore, this rotor 11 is used as a generator (not shown).
When the magnet 16 is attached to the generator, the magnet 16 is surrounded by the protective cover 19 made of synthetic resin as described above from the front, back, left and right, except for the upper and lower surfaces, so that the magnet 16 does not flow to the stator of the generator. The so-called leakage magnetic flux is greatly reduced, and the effective magnetic flux flowing through the stator can be greatly increased.

Also, the magnet 16 is connected to the convex pole portion 13B of the iron core 13.
When inserting and fitting the magnet 16 into the concave groove 13C provided in the groove 13C, the magnet 16 is covered with the protective cover 19 described above. Even if the material is brittle, damage during insertion and fitting can be almost completely prevented.

[Effect of idea]

As is clear from the above explanation, the present invention consists of a rotor shaft, a convex pole-shaped iron core that is laminated and fitted to the rotor shaft in large numbers, and a field coil that is wound around the iron core. In the rotor of a self-excited generator, a dovetail-shaped concave groove is provided in the convex pole part of the iron core, and a magnet whose front, rear, left, and right sides, excluding the top and bottom surfaces, are surrounded by synthetic resin protective covers is placed in the groove. By a very simple modification of directional magnetization and fitting, the leakage magnetic flux of conventional rotors can be significantly reduced, and the effective magnetic flux flowing to the stator of the self-excited generator can be greatly increased. Therefore, in the self-excited generator equipped with the rotor of the present invention, the rise characteristics of the initial output voltage can be significantly improved compared to the conventional ones.

Furthermore, since it is possible to almost completely prevent the magnet from being damaged when it is inserted and fitted into the dovetail groove provided on the convex pole of the iron core, the manufacturing cost can be significantly reduced. I can do it.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a conventional rotor of this kind, Fig. 2 is a cross-sectional view showing the relationship between the rotor and stator, Fig. 3 is a perspective view of essential parts of a rotor according to an embodiment of the present invention, and Fig. 4 and FIG. 5 is a perspective view of the magnets and protective cover fitted to the rotor. In the figure, 11 is a rotor, 12 is a rotor shaft, 13 is an iron core, 13B is a convex pole part, 13C is a dovetail groove, 1
4 is a coil bobbin, 15 is a field coil, 16 is a magnet, and 19 is a protective cover.

Claims (1)

[Scope of utility model registration request] In the rotor of a self-excited generator, the rotor comprises a rotor shaft, a convex-pole iron core laminated and fitted onto the rotor shaft, and a field coil wound around the core. A dovetail-shaped concave groove is provided in the part, and a magnet whose front, rear, left, and right sides, excluding the top and bottom surfaces, are surrounded by synthetic resin protective covers is radially magnetized and fitted into the concave groove. Rotor of self-excited generator.