JPS60118036A - Cooler of magneto generator - Google Patents

Abstract

PURPOSE:To efficiently circulate cooling air by providing a guide fin for guiding fluid of cooling air to an air gap in which a stator and an engine case are oppositely spaced in the axial direction of an engine. CONSTITUTION:When a rotor 1 rotates, cooling air stream generated by a fan 7 is passed between a hole 62 formed at a flywheel 6 between a cylinder 61 and an engine case cover 14 like a circulating arrow D, flowed to the side end of the engine case of the rotor, guided smoothly by a fin 133 inclined in the rotating direction, and flowed to between poles 122 of a generating coil 12, thereby effectively cooling the coil 12. The self-heating energy of the coil 12 increases the surface area by the installation of the fin 133, but is dissipated from a bobbin, thereby improving the heat dissipating effect.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an air cooling device for a magnet generator installed in an internal combustion engine.

[Background of the invention]

A small magnet generator for two-wheeled vehicles (U.S. Patent No. 3)
As shown in No. 219859, a structure in which a rotor is fixed to the drive shaft of the engine, a stator is fixed to the engine case, and the structure is sealed by covering with a case cover is often used.

In this heel magnet generator, a cooling device is known that has a structure in which a cooling fan is fixed to the rotor to circulate air within the case cover.

However, simply by fixing the fins to the rotor as described above, it is difficult to effectively circulate cold air around the generator, so there is a technical problem that the cooling efficiency of the generating coil is not good.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and includes fixing a rotor having an excitation magnet on its inner diameter to a drive shaft of an internal combustion engine, and an iron core having a power generation coil wound thereon facing the rotor. A magnet generator with a radially arranged stator attached to the engine case, the above components covered with an engine case cover, and an air cooling fan fixed inside the rotor, can be used for cooling with a simple configuration. An object of the present invention is to provide a cooling device that can efficiently circulate air.

[Summary of the invention]

In order to achieve the above object, the cooling device of the present invention guides the flow of cooling air into the gap where the stator and the engine case are opposed to each other in the engine axis direction in the magnet generator having the above structure. The invention is characterized by the provision of guide fins.

[Embodiments of the invention]

Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 is a sectional view of a magnet generator equipped with an embodiment of the cooling device of the present invention, taken along a plane including the rotating shaft. FIG. 2 is a sectional view taken along the line AA in FIG. 1.

1 is a drive shaft of the engine, and a tapered portion 2 is formed at one end of the drive shaft. A cylindrical boss 3 is tapered on its inner circumferential surface and fitted into the tapered portion 2, and is tightened with a nut 4 via a washer 5. A bowl-shaped seven flywheel 6 is fixed to the seventh rank part of the above-mentioned post 3 with a rivet 8, and cooling fins 7 are fixed to the flywheel 6.

On the inner peripheral surface of the cylindrical portion 61 of the flywheel 6, excitation ferrite magnets 8 are arranged so as to alternately have different polarities.

A power generation core 11 wrapped with a power generation coil 12 is attached to the engine case 1.
It is fixed at 0.

FIG. 3 is a perspective view of a part of the power generation core and the vicinity of the power generation coil 11 wound around the power generation core.

A 13-piece coil winding bobbin is fitted onto the core 11, and the conductor 1 is
21 is wound. The above bobbin 13 has a core 1
A flange 132 extending in the outer radial direction of the fin 132 is provided, and a fin 133 is integrally provided substantially perpendicularly to the flange.

The fins 133 are arranged in the radial direction □ as shown in FIG.
It is twisted by an angle θ with respect to r, and is inclined in the direction of arrow B, which is the rotational direction of the rotor. In the present invention, being inclined in the rotational direction means that the flow path direction (for example, arrow C) from the inflow side to the outflow side of the guide fin has a component in the direction of arrow B described above.

In the cooling device configured as described above, as the rotor rotates 10 times, the cooling air flow generated by the fan 7 passes through the opening 62 provided in the flywheel 6 as shown by the circulation arrow in FIG. 61 and the engine case cover 14, the fluid flows to the end of the rotor on the engine case side, is smoothly guided by the fins 133 inclined in the direction of rotation as described above, and flows into the gap 122 between the poles of the generating coil 12. The liquid flows in and effectively cools the power generating coil 12. In addition, the power generation coil 12
The self-heating energy is also radiated from the bobbin whose surface area has been increased by installing the fins 133, thereby improving the heat radiation effect.

FIG. 4 shows an embodiment different from the above, in which the collar portion 1 of the bobbin
32 is extended to the outer diameter side of the outer periphery 61 of the flywheel 6 of the rotor. Effects specific to this embodiment will be described next.

When the flywheel end face 62 rotates at a circumferential speed, a cylindrical air ring is formed between the end face 62 and the engine case due to the viscosity of the air, and the cooling air flow is guided to the fins 133 due to this ring. be prevented from becoming involved. As in this embodiment, the flange portion 132 is made larger in diameter than the flywheel outer circumference 61 by 41 mm. This will prevent the negative effects of the monkeys and further improve the efficiency of cooling air circulation.

〔Effect of the invention〕

As detailed above, according to the device of the present invention, a rotor having an excitation magnet on its inner diameter is fixed to the drive shaft of an internal combustion engine, and a generating coil is wound around the rotor so as to face the rotor. A stator with a radial iron core is attached to the engine case, and the periphery of the above-mentioned components is covered with an engine case bracket, and an air-cooling fan is placed inside the rotor between magnet power generation plates, A simple structure in which fins are provided to guide the flow of cooling air in the gap between the stator and the engine case, which are spaced apart from each other in the direction of the engine axis, allows the cooling air to circulate efficiently. It has practical effects.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a magnet generator equipped with a cooling device of the present invention mounted on an engine. Figure 2 is a sectional view taken along line A-A in Figure 1.
FIG. 3 is a P-bottom view of FIG. 1. FIG. 4 is a side sectional view of another embodiment.

Claims (1)

[Claims] 1. A rotor having an excitation magnet on its inner diameter is fixed to the drive shaft of an internal combustion engine, and an iron core having a power generating coil wound thereon is provided radially opposite the rotor. In a magnet generator in which the stator is attached to the engine case, the periphery of the above-mentioned components is covered with an engine case cover, and an air cooling fan is fixed inside the rotor, the stator and the engine case are connected to the engine shaft. A cooling device for a magnet generator, characterized in that fins for guiding the flow of cooling air are provided in voids spaced apart from each other in opposite directions. 2. The cooling air guide fins are integrally molded with the bobbin for winding the power generation coil in the shape of an extension, and the direction of installation of the fins is in accordance with the rotation of the rotor with respect to the radial direction with respect to the engine axis. 2. The cooling device for a magnet generator according to claim 1, wherein the cooling device is tilted in a direction. 3. The cooling device for a magnet generator according to claim 2, wherein the guide fin has an outer circumferential portion centered on the engine axis having a larger diameter than an outer circumferential portion of the rotor.