JPH07123339B2 - Vehicle generator cooling structure - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention is a rotor attached to an engine output shaft,
The present invention relates to a cooling structure for a vehicle generator in which a stator coil arranged to face the rotor is housed in a generator cover.

[Prior art]

Overheating of the vehicular generator, and in particular of its stator coil, can lead to the disadvantage of reduced generator output. In order to prevent this, a cooling structure for it has been conventionally considered. One of them is that the iron core of the stator coil is fixed to the engine case, and the heat generated in the stator coil is released to the engine case by utilizing the thermal gradient between the iron core side and the engine case. Some are designed to be cooled. Further, in order to cool the generator, ventilation holes are formed in the side wall of the generator, and cooling air is circulated in the generator by a fan attached to the rotor (for example, the actual open sho 56
-35865).

[Problems to be Solved by the Invention]

By the way, in the former case of the conventional structure, a considerable cooling effect can be obtained when the engine case has a relatively low temperature and the thermal gradient is large, but the engine case becomes considerably high in temperature with the operation of the engine. When the thermal gradient is small, there is a problem that the heat generated by the stator coil cannot escape to the engine case side and a sufficient cooling effect cannot be obtained. Further, in the latter, since the cooling air is guided directly into the generator and is circulated, when rainwater or the like invades, the coil or the like is violated by water and loses the insulating property, degrading the performance of the generator. There is a problem. The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle generator capable of efficiently cooling the vehicle generator without deteriorating the performance of the vehicle generator. It is intended to provide a cooling structure for a generator.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the cooling structure for a vehicle generator according to the present invention has a stator coil mounting base fixed to an engine case, and a mounting surface between the engine case and the mounting base. The air passage for introducing the vehicle traveling wind between the mounting surfaces is formed.

[Action]

Since it is the cooling structure for the vehicle generator configured as described above, when the vehicle travels, the vehicle traveling wind is introduced into the air passage between the mounting surfaces of the engine case and the mounting base, and the stator coil The mounting base of is cooled by air. As a result, the thermal gradient between the stator coil and the mounting base of the stator coil is increased, and the generator is cooled efficiently. And, rainwater does not enter the rotor, the stator coil, etc., which are the main parts of the generator.

【Example】

Embodiments of the present invention will be described with reference to the accompanying drawings. In the figure, 2 is a front wheel, 4 is a rear wheel, 6 is a frame, 8 is an engine, and 10 is a crankcase as an engine case. A generator 12 is attached to the crankcase 10. In the generator 12, a rotor 18 attached to, for example, a crankshaft 16 as an engine output shaft, and a stator coil 20 arranged to face the rotor 18 are housed in a generator cover 14. A stator coil mounting base 24 to which the iron core 22 of the stator coil 20 is mounted is fixed to the crankcase 10. The stator coil mounting base 24 has a bottomed cylindrical shape, and has an opening 26 for leading out one end of the crankshaft 16 at the center of the bottom surface thereof. The iron core 22 is fixed to the thick portion around the opening 26 with a bolt 28. On the other hand, the periphery of the bottom of the stator coil mounting base 24 bulges toward the crankcase 10, and a notch is formed along the periphery. Further, above the notch on the traveling direction side, there is an air guide duct 29 having a U-shaped cross section, the cross sectional shape of which extends in the vehicle traveling direction.
It is formed integrally with the stator coil mounting base 24. By mounting the stator coil mounting base 24 on the crankcase 10 with the bolts 30, a plurality of openings 32 are provided between the mounting surfaces between the stator coil mounting base 24 and the crankcase 10 and communicate with these openings 32. An air passage 34 is formed. On the other hand, in the rotor 18, a plurality of permanent magnets 38 are fixed to the inner peripheral surface of the flywheel 36, and the open end of the rotor 18 is fixed to the stator coil mounting base 24 side and fixed to the tip of the crankshaft 16 by a bolt 40. ing. In this state, the permanent magnet 38 is arranged to face the iron core 22 of the stator coil 20. Then, the generator cover 14 is fixed to the stator coil mounting base 24 from above the rotor 18 with the bolt 42. Next, the operation of the embodiment having the above-mentioned configuration will be described. When the rotor 18 rotates together with the crankshaft 16, a generated current flows through the stator coil 20. The heat generated by this is conducted mainly to the stator coil mounting base 24. On the other hand, the traveling wind guided by the wind guide duct 29 by the traveling of the motorcycle and introduced from the opening 32 in the front in the traveling direction flows rearward along the air passage 34 and flows out from the opening 32 in the rear in the traveling direction. . At this time, the traveling air flowing through the air passage 34 cools the stator coil mounting base 24 by air. Although the plurality of openings 32 are formed between the mounting surfaces between the stator coil mounting base 24 and the crankcase 10 in the above-described embodiment, it is sufficient that the traveling wind can be introduced into the air passage 34. 32 is not always necessary, and may be formed so that the entire periphery between the mounting surfaces is opened, for example. Further, by forming heat radiation fins along the flow of traveling wind on the bottom surface of the stator coil mounting base 24 facing the air passage 34 and the surface of the generator cover 14, the heat radiation area is expanded, which further enhances the cooling effect of the generator. Preferred for improving. Further, as shown in FIG. 4, when the guide plate 44 along the flow direction of the traveling wind is integrally formed with the stator coil mounting base 24 'on the inner surface of the air guide duct 29', the traveling wind is rectified to efficiently travel. Wind can be introduced into the air passage 34,
Further, since the heat radiation area is expanded, the cooling effect of the generator 12 'can be further improved. Further, in the above-described embodiment, the generator 12 is used as the crankcase.
Although the case where the generator is attached to 10 has been described as an example, since the rotational force of the rotor is also given by the shaft of the mission or the like, the generator may be attached to the mission case or the like, for example. When the air duct 29 is formed integrally with the stator coil mounting base 24 as in this embodiment, the heat dissipation effect from the air duct 29 itself can be obtained.
The generator can be cooled more efficiently as compared with the case where such an integrated air duct is not formed.

【The invention's effect】

In the cooling structure for a vehicle generator according to the present invention, an air passage for circulating traveling air is formed between the engine case and the stator coil mounting base. Therefore, when the vehicle travels, the vehicle traveling wind is introduced into the air passage between the mounting surfaces of the engine case and the mounting base, and the mounting base of the stator coil is air-cooled. The heat gradient between the mounting base and the generator is increased, and the generator is cooled efficiently. As a result, according to the present invention, when the same power generation output as that of the conventional generator is obtained, the generator can be made smaller than the conventional generator. Since rainwater does not enter the rotor, the stator coil, etc., which are the main parts of the generator, the performance of the vehicle generator is not deteriorated.

[Brief description of drawings]

FIG. 1 is a side view of a motorcycle equipped with a cooling structure for a vehicle generator according to an embodiment of the present invention, and FIG. 2 is an external perspective view showing an enlarged view of the periphery of the vehicle generator. FIG. 3 is a vertical cross-sectional view of the vehicular generator according to the above embodiment, and FIG. 4 is an external perspective view showing another embodiment from the mounting surface side of the generator. 10 …… Engine case, 12,12 ′ …… Generator, 14 …… Generator cover, 16 …… Engine output shaft, 18 …… Rotor, 20
...... Stator coil, 24,24 '…… Stator coil mounting base, 34 …… Air passage.

Claims (1)

[Claims] 1. A mounting base fixed to an engine case, a stator coil fixed to the mounting base, a rotor mounted on an engine output shaft extending from a central portion of the mounting base, and the stator coil. A cooling structure for a vehicle generator, comprising: a generator cover attached to the attachment base so as to cover the rotor, wherein a vehicle is mounted between mutual attachment surfaces of the engine case and the attachment base. A cooling structure for a vehicle generator, wherein an air passage for introducing traveling wind between the mounting surfaces is formed.