JPS58172961A - Ac generator for vehicle - Google Patents

Abstract

PURPOSE:To eliminate a trouble due to dusts and muddy water by enclosing a diode in a metal case, thereby constructing a rectifier. CONSTITUTION:An AC generator for a vehicle has a field core 4 having a field coil 10 fixed to a rotational shaft 1, and a stator core 11, on which a stator coil 8 is wound around the periphery of the core 4. A rectifier 25 which is connected to the coil 8 is mounted in a metal case 28, and has a diode 26 for the heat sink of the bottom 28a of the case 28. The bottom 28a of the case 28 of the rectifier 25 is mounted in contact with the part 15 of a housing. Cooling air is introduced into a groove 32 between the bottom 28a of the case 28 and the part 15 of the housing by a cooling fan 30.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicular alternator that supplies DC power to an in-vehicle electrical load.

Among conventional vehicle AC generators, those for four-wheeled passenger cars have a rectifier inside the generator housing, but this rectifier has pellet-shaped diodes mounted on a cooling plate that serves as a heat sink and is supported within the housing. It is something.

Therefore, the surface of the cooling plate, the diodes, and the wiring between the diodes are directly exposed to the outside air, and if muddy water or salt-containing water enters, electrolytic corrosion occurs, causing corrosion of various parts and current flow. There was a problem with leaks (2).

In addition, in the case of generators for two-wheeled vehicles, only the sealed generator body is installed adjacent to the engine, and the rectifier and voltage regulator are located elsewhere, and there is no connection between the generator body, rectifier, and voltage regulator. were connected by wiring.

In such a structure, the wiring work is troublesome and the installation work takes a lot of man-hours. In order to solve this problem, it is conceivable to use a generator for a two-wheeled vehicle that has a structure similar to the conventional generator for a four-wheeled passenger vehicle as described above.

However, generators for two-wheeled vehicles are required to be extremely compact, and because they are often directly exposed to muddy water, they are required to have a structure that does not cause failures due to electrolytic corrosion or dust adhesion.

In view of the above-mentioned problems, the present invention provides a vehicle alternating current generator having a rectifier that does not impair the function of the rectifier due to the intrusion of muddy water or dust, has good cooling, and can be constructed in a small size. The first embodiment of the generator of the present invention is shown in the drawings (3) and will be explained below. In Figs. The shaft is driven by the vehicle engine. 2 is an oil seal, 3 is a front bearing, 4 is a field core, 5 is a front cooling fan welded to the end face of the field core 4, 6 is an O-ring, and 7 is a front The housing is made of aluminum.

8 is a stator winding, 9 is a nail-shaped tank core of a field core, 10 is a field winding, 11 is a stator core, and 12 is a bolt for tightening.

Reference numeral 13 indicates a joint surface between the front housing 7 and the rear housing 14, and 14 indicates a rear housing having both end surfaces 14a rounded and egg-shaped, and is made of aluminum. Reference numeral 15 denotes a bearing holding plate which is attached to the rear housing 14 with screws 16 shown in FIG. 4 and partitions the front housing 7 and the rear housing 14.

17 is a rear bearing, 1B is a brush holder, and 19 is a brush that is in sliding contact with the slip ring 20.

Reference numeral 21 denotes a slip ring opening cover that covers the slip ring portion, and in this case, it is integrally formed with the bearing holding plate 15 (4) and has a brush introduction opening at the upper end of a U-shaped cross section. Further, an elastic body 22 is attached to the rear end of the slip ring cover 21.

Reference numerals 23 and 23a indicate a large number of ventilation windows provided in the rear housing 14, especially between the ventilation windows 23a on the outer periphery.
It is reinforced with 4.

Reference numeral 25 denotes a rectifier, in which a Gretz-connected three-phase full-wave rectifier diode 26 is mounted, and a part of the diode is connected to the bottom 28a of a metal case 28, which serves as a heat sink, through an insulating thin layer 27. The other diodes are directly in close contact with the bottom 28a of the metal case 28. Further, the terminal lead-out portion of the metal case 28 is sealed with a sealant 29 made of synthetic resin. This metal case has an arc shape and is made of aluminum bearing holding plate 15.
It is attached with screws 16 so as to be in close contact with the flat surface of.

In addition, one of the ventilation openings 31 is formed in the portion of the bearing holding plate 15 that faces the rear cooling fan 30, and the air introduced from the ventilation window 23 of the rear housing 14 (5) flows through the metal rectifier 25. After flowing around the outer periphery of the case 28, it reaches the opening 31, passes through the stator winding 8, and is discharged from the outer peripheral ventilation window 23a of the rear housing 14.

In addition, a plurality of grooves 32 (Figs. 1 and 3) are formed in the bearing holding plate 15 in contact with the metal case bottom 28a, so that lice can get around to the back side of the metal case bottom 28a, which serves as a heat sink. It has become.

33 is a wiring connecting the stator winding 8 and the rectifier 25;
34 is an insulating bushing that insulates this wiring 33 from the bearing holding plate 15. Reference numeral 13 indicates a pilot joint, and reference numeral 7a indicates a mounting stay integrally formed with the front housing 7.

Next, in FIG. 3, the rotating shaft and the brush are omitted from illustration for the sake of simplification.

40 is a voltage regulator, which has a built-in transistor inside the case and controls the current flowing through the field winding 10;
The electromotive force of the stator winding 8 is controlled to be approximately constant. The voltage regulator 40 is attached to the bearing holding plate 15 with screws 16 (6). Reference numeral 18 denotes a brush holder, which is attached to the bearing holding plate 15 with screws 41.

28 is a metal case of the rectifier 25, which is attached to the bearing holding plate 15 with screws 16. 42 is an output terminal of the rectifier, and 34a is a synthetic resin holding plate integrated with an insulating bushing 34 that supports the wiring 33.

31 and 32 are openings provided in the bearing holding plate 15;
In particular, the opening 32 is a groove formed in the bearing holding plate 15 and extends around the back side of the rectifier 25.

Further, the outer peripheral end 15a of the bearing holding plate 15 is shown in FIGS. 1 and 4.
As shown in the figure, it abuts against the stepped portion of the rear housing 14 and is joined with a spigot. Note that 150 in FIG. 4 is a spacer, and screws 16 fasten and fix the bearing holding plate 15 to the rear housing 14.

In addition, a groove-shaped brush powder discharge port 50 (FIG. 1) is formed between the rear bearing 17 and the bearing holding plate I5, and the rotation of the rear cooling fan 30 allows air to flow inside the slip ring cover 21. The brush powder flows from the discharge port (7) 50 to the discharge port (7) 50 to discharge the brush powder.

Further, this air passes through a maze-like passage inside the brush holder 18 and enters the slip ring cover 21.

Therefore, the brush 19 inside the brush holder 18 is also cooled.

The rear cooling fan 30 is a so-called mixed flow fan, and has the action of a centrifugal fan that sends air around the rear bearing 17 to the stator winding 8 side, and a part of the air to the field core 411! It acts as an axial fan that sends the flow to the front cooling fan 5 side via the side. Furthermore, the front cooling fan 5 is a centrifugal fan, which stirs the air in this area and discharges hot air through a ventilation window 7C provided in the front housing 7.

Next, FIGS. 5 to 7 showing the second embodiment will be explained. In this embodiment, a stay 15d is attached to the bearing holding plate 15.
are provided integrally, and the bearing holding plate 15 and the rear housing 14 are connected by a spigot surface 60, and the bearing holding plate 15 and the front housing 7 are connected by a spigot surface 61.

Furthermore, the bottom part 28a of the metal case 28 of the rectifier 25(8) is closely contacted with the flat surface of the bearing holding plate 15, and there are grooves 32 partially forming a gap in the flat surface of the bearing holding plate 15. Since the rear cooling fan 30 rotates, the wind introduced from the ventilation window 23 of the rear housing 14 flows as shown by the arrow, and flows inside the groove 32, that is, at the bottom of the metal case 28, which serves as a heat sink. .

The rectifier 25 has an arc shape as shown in FIGS. 7 and 6, and is provided with a bellet of diodes 26 inside, and one group of diodes has a metal case with a ceramic sprayed layer 27 serving as a thin insulating layer. It is insulated from the bottom portion 28a.

Note that the space 65 around the diode 26 may be filled with an epoxy resin mixed with magnesium powder serving as a synthetic resin, or the space 65 may be filled with cooling oil and sealed. 29 is a sealing material made of synthetic resin, thus preventing moisture and dust from entering the metal case 28.

Note that in each of the above embodiments, a vehicle alternator for a motorcycle is mentioned, but the reason for this is that generators for motorcycles (9) are often exposed to flying water and mud, and in addition, they are required to be smaller. This is because it is most suitable for the use of the present invention. However, the present invention is not limited to this type of two-wheeled vehicle, and may be used for four-wheeled vehicles. It is particularly suitable for four-wheeled vehicles that travel on rough roads or in coastal areas.

As described above, in the present invention, since the rectifier δ has the diode 26 sealed inside the metal case 28, there is no failure due to dust or muddy water, and even if the rectifier δ is made small, heat dissipation is achieved by the following measures. It has the effect of having good sex.

In other words, the bottom part 28a of the metal case of the rectifier 25 serves as a heat sink, and since this is in close contact with the part 15 of the metal housing of the generator, the heat from the heat sink is transferred to the outside through the housing 15, 7.14. can be dissipated to

In addition, a portion of the air from the cooling fan 30 flows through the groove 32 between the housing 15 and the metal case bottom 28a that serves as a heat sink.
Since the air passes through the air, the heat sink is effectively cooled by the cooling fan 30 (10).

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view showing a first embodiment of the generator of the present invention, Fig. 2 is an external view of the generator shown in Fig. 1 seen from the rear, and Fig. 3 is a rear housing of the generator shown in Fig. 1. FIG. 4 is a longitudinal cross-sectional view of the first embodiment shown by cutting at a different angle from FIG. 1, and FIG.
The figure is a partial vertical sectional view showing the second embodiment of the present invention, FIG. 6 is a plan view of the rectifier as seen from the direction of arrow A in FIG.
The figure is an enlarged view of the rectifier of FIG. 5. ■... Rotating shaft, 10... Field winding, 4... Field core. 3.17...Bearing, 8...Stator winding, 11K stator core, 7, 14, 1.5... Housing, 5.
30... Cooling fan, 25... Rectifier. Representative Patent Attorney Takashi Okabe'11 (11) Figure 1, Figure 211

Claims (1)

[Claims] A rotating shaft (1) driven by a vehicle engine, a field core (4) having a field winding (10) fixed to the rotating shaft (1), and a field core (4) having a field winding (10) fixed to the rotating shaft (1). ) supporting the bearing (3,1
7), a stator core (1'l) surrounding the field core (4) and having the stator winding (8) wound thereon; A metal housing (7, 1) surrounding the stator core (11)
4, 15), a cooling fan (5, 30) rotatably driven by the rotating shaft (1), and a cooling fan (5, 30) provided in the housing (7, 14, 15), and the stator winding (8).
) for rectifying multiphase alternating current, the rectifier (25)
is mounted in the metal case (28) and the metal case (28)
) whose heat sink is the bottom (28a) of the diode (
(26), (1) and the bottom (28) of the metal case (28) of the rectifier (25);
28a) is closely attached to the housing part (15), and the cooling fan (30) allows the bottom part (28B> of the metal case (28) to connect with the housing part (15). A vehicle alternator characterized in that cooling air is introduced into a groove (32) between the alternators.