JP2522872Y2 - Flywheel magnet rotor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flywheel magnet rotor mounted on an internal combustion engine.

[0002]

2. Description of the Related Art As a flywheel magnet rotor attached to an internal combustion engine, a concave portion for attaching a magnet is provided on the outer periphery of a flywheel formed substantially in a cup shape, and a rotating field for ignition of the internal combustion engine is provided in the concave portion. Some have a permanent magnet attached. In this type of magnet rotor, a number of blowing blades are arranged in a circumferential direction at a portion of the bottom wall of the flywheel near the outer periphery, and the blowing blades generate an air flow for cooling the engine. Many.

When a blower is provided on the bottom wall of a flywheel having a magnet mounting recess on the outer periphery, it is necessary to escape the recess and provide a blower at the position where the recess is provided. It is unavoidable that the length of the provided blower is shorter than that of the other blowers by the depth of the concave portion.

[0004]

SUMMARY OF THE INVENTION As described above, a flywheel magnet rotor of the type in which a concave portion for mounting a magnet is provided on the outer periphery of a flywheel having a blower blade on a bottom wall portion and a magnet is mounted in the concave portion. In, the flywheel is usually manufactured by casting. In the case of manufacturing a flywheel by casting, if there is a portion where cooling is too early, the hardness of the portion becomes high, the portion becomes brittle, and is easily chipped. Therefore, in order to obtain a flywheel with high strength, it is necessary to cool the whole over a predetermined time after pouring the molten metal into the mold.

However, in the flywheel used in the conventional magnet rotor, the length of the blower at the position where the recess for mounting the magnet is provided is shorter, and the heat capacity is smaller than that of the other blowers. Therefore, at the time of casting, there is a problem that the blowing wing located at the position of the concave portion is cooled faster than other blowing wings, and has a higher hardness and becomes brittle. When the blower blades become brittle, there is a possibility that the blower blades may be chipped when the rotor is carried or when the rotor is attached to the engine.

Further, in the above flywheel magnet rotor, a concave portion is provided on the outer periphery of the flywheel, and two blowers located on both sides of the concave portion are in a state where an object easily hits them. There is a problem in that the blower blades are damaged by tools or the like and chippings often occur.

Further, in the conventional flywheel magnet rotor, since the weight of the portion provided with the magnet mounting concave portion is reduced, the weight balance of the rotor is deteriorated, and vibration is liable to occur with rotation. there were. In order to prevent this, complicated processing for balancing the weight of the flywheel was necessary.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flywheel magnet rotor capable of improving the strength of a blower at a portion provided with a magnet mounting recess and improving the weight balance. It is in.

[0009]

According to the present invention, there is provided a flywheel comprising a plurality of blower blades arranged in a circumferential direction at a portion of a bottom wall near an outer periphery and a concave portion for attaching a magnet at the outer periphery. And a permanent magnet mounted in a recess provided on the outer periphery of the flywheel.

[0010] The blower wing provided at the position of the concave portion of the flywheel is formed shorter than the other blower wings by an amount corresponding to the depth of the concave portion, but in the present invention, it is provided at the position of the concave portion. The thickness of each of the blowers provided and the two blowers provided on both sides of the concave portion was set to be larger than the thicknesses of the other blowers.

[0011]

As described above, the blower blade located at the position of the concave portion for mounting the magnet and the air blower provided on both sides of the concave portion, respectively.
If the thicknesses of the two blow blades are increased, the weight of the portion provided with the concave portion can be increased, so that the weight balance of the rotor can be improved.

Further, since the heat capacity of the blower at the position of the recess for mounting the magnet is increased, the cooling speed of the blower at the position of the recess at the time of casting can be reduced, and the position of the recess for mounting the magnet can be reduced. The strength of the blower can be increased.

Further, with the above configuration, the two blades on both sides of the concave portion, which are in a state where the object can easily hit, can be strengthened, so that the blades can be prevented from being damaged.

[0014]

1 and 2 show an embodiment of the present invention. FIG. 1 is a front view, and FIG. 2 is a sectional view taken along line AA of FIG. In these figures, reference numeral 1 denotes a substantially cup-shaped flywheel formed by casting.
It has a bottom wall 1a, an outer peripheral wall 1b, and an inner peripheral wall 1c integrally. A boss 1d is provided at the center of the bottom wall 1a.
Is provided, and the boss portion 1d is fitted to an output shaft of an engine (not shown). One magnet mounting recess 1e is formed on the outer periphery of the outer peripheral wall 1b of the flywheel.
The permanent magnet 2 is fixed in e by bonding or the like. A pole piece 3 is fixed to the pole face of the permanent magnet 2 by bonding or the like. In the illustrated example, a protective case 2a (see FIG. 2) that covers the periphery of the magnet 2 is provided, and the magnet is prevented from being damaged by the protective case.

A large number of blower blades 1f1, 1f2,... 1fn having a bow shape are protruded from the bottom wall portion of the flywheel near the outer periphery at intervals in the circumferential direction. Among these blowers, the blowers 1f2 and 1f3 located at the positions where the recesses 1e are provided are formed to be shorter by the depth of the recesses 1e.

In the present invention, the thickness of the blowers 1f2 and 1f3 at the position of the recess 1e and the thickness of the blowers 1f1 and 1f4 provided on both sides of the recess 1e are different from those of the other blowers 1f5. It is set to be larger than the thickness dimension of 〜1fn. Here, the thickness of the blower blades 1f2 and 1f3 is
The volume of each of the blowing blades is set to be substantially equal to the volume of the other blowing blades 1f5 to 1fn. Further, by increasing the thickness dimension of the blower blades 1f1 to 1f4, the concave portion 1e is formed.
By increasing the weight in the vicinity, the weight of the flywheel is balanced.

A ring-shaped magnet 4 is attached to the inner periphery of the inner peripheral wall 1c of the flywheel, and the magnet 4 is magnetized so as to form a predetermined number of field poles.

The flywheel 1 and the permanent magnets 2 and 4 constitute a flywheel magnet rotor.

A stator (not shown) in which a generating coil is wound around an armature core is disposed inside the magnet 4, and the stator and the flywheel magnet rotor ignite a head lamp, a battery charging circuit, and the like. A magnet generator that drives a load other than the device is configured.

On the outer peripheral side of the flywheel, an ignition power generation coil is wound around an iron core having at both ends a magnetic pole portion which can oppose the magnetic pole of the magnet 2 and the outer peripheral surface of the flywheel on both sides of the concave portion 1e. When the magnet 2 passes through the position of the magnetic pole portion of the stator, a voltage is induced in the ignition power generation coil. The output of the ignition power generation coil is used to drive an ignition device for an internal combustion engine.

In the above flywheel magnet rotor, when the thickness of the blowers 1f2 and 1f3 is the same as the thickness of the other blowers, when the flywheel is cast, the thickness of these blowers 1f2 and 1f3 is increased. The cooling rate is too fast,
Both wings become brittle. On the other hand, if the thickness of the blowers 1f2 and 1f3 is increased as in the present invention, the cooling speed of both blowers can be made equal to that of the other blowers.
The blower blades 1f2 and 1f3 can be prevented from becoming weak.

In the embodiment described above, the flywheel is provided with the inner peripheral wall 1c, and the magnet 4 is attached to the inner periphery of the inner peripheral wall to constitute a magnet generator for supplying electric power to loads other than the ignition device. However, when it is not necessary to supply power to loads other than the ignition device, the magnet 4 is omitted. When the magnet 4 is not required, the inner peripheral wall 1c can be omitted.

[0023]

As described above, according to the present invention, the thickness of the blower located at the position of the recess for mounting the magnet and the two blowers provided on both sides of the recess are increased. By increasing the weight of the portion provided with the mounting concave portion, it is possible to improve the weight balance of the rotor.

Further, according to the present invention, since the heat capacity of the blower at the position of the concave portion for mounting the magnet is increased, the cooling speed of the blower at the position of the concave portion during casting of the flywheel is prevented from becoming too high. Therefore, there is an advantage that the strength of the blower at the position of the magnet attachment concave portion can be prevented from lowering.

Further, according to the present invention, the two wings on both sides of the concave portion in a state where an object easily hits can be strengthened, so that there is an advantage that these wings can be prevented from being damaged. is there.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Flywheel, 1a ... Bottom wall part, 1b ... Outer peripheral wall part, 1c ... Inner peripheral wall part, 1d ... Boss part, 1e ... Magnet mounting recessed part, 1f1-1fn ... Blower blade.

Claims (1)

(57) [Scope of request for utility model registration] 1. A flywheel having a plurality of blower blades arranged in a circumferential direction protruding from a portion near an outer periphery of a bottom wall portion, and a concave portion for attaching a magnet on an outer peripheral portion, and provided on an outer periphery of the flywheel. And a permanent magnet mounted in the recessed portion,
The blower wing provided at the position of the concave portion of the flywheel is a flywheel magnet rotor formed to be shorter than the other blower wings by an amount corresponding to the depth of the concave portion, and provided at the position of the concave portion. A flywheel magnet rotor, wherein the blower wings and the two blower wings provided on both sides of the recess are formed to be thicker than the other blower wings.