JPS60109748A - Ac generator for vehicle - Google Patents

Abstract

PURPOSE:To improve the vibration resistance and to reduce the size by disposing a pair of main rectifying diodes at one positions symmetrical to a bolt for clamping a diode cooling fin, and disposing an auxiliary rectifying diode at the other. CONSTITUTION:A pair of cooling fins 13, 14 of horseshoe shape are secured at the inner and outer peripheries with a bolt 17a secured to a rear side bracket 2, cooling air is sucked by a fan 8b from a window 2a of the bracket 2 as designated by an arrow W, and discharged from 2b. Main and sub commutators, not shown, are arranged on the fins 13, 14. Thus, the vibration resistance is improved to improved the cooling effect.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a rectifying diode used in an automotive alternator.

[Background of the invention]

Conventionally, this type of diode has a main rectifier diode and an auxiliary rectifier diode arranged in an arc shape parallel to the inside of the generator bracket, as disclosed in Japanese Patent Application Laid-Open No. 53-416407.
was. On the other hand, as shown in Japanese Utility Model Application No. 56-164678, there is also a structure in which main rectifying diodes are arranged in two arc shapes with different radii, but this structure does not include auxiliary rectifying diodes. However, with all of these structures, it has been difficult to achieve both improved vibration resistance and a compact shape.

[Purpose of the invention]

An object of the present invention is to provide a diode structure that has excellent vibration resistance and has a compact shape. [Summary of the Invention] Place the main rectifier diode of
An auxiliary rectifier diode is placed on the other side to improve vibration resistance and reduce the number of vibrations.

[Embodiments of the invention]

In Figure 1, front side bracket 1. The rear side tilting bracket 2 holds an annular stator 3 therebetween and is integrally coupled with a through bolt (not shown) to form a generator main body. The stator 3 is composed of a stator core 3a and a stator coil 3b wound through slots (not shown). The brackets 1 and 2 have a rotating shaft 4.
is rotatably supported by bearings 5 and 6, and a rotor 7 is coupled to this rotating shaft 4. The rotor 7 has a pair of claw-shaped rotor cores 7a and 7b, a yoke 7c, and a field coil 7d installed therebetween.

Also, centrifugal fans 8a are provided on both sides of the rotor cores 7a and 7b.
, gb are firmly fixed by welding or the like, and a driving pulley 9 is connected to the rotating shaft 4, and the rotational force is transmitted to the engine etc. by a belt (not shown).

Previous iL! The first centrifugal fan 8a, through its rotation, sends cooling air to the cooling air intake vent 1 of the front bracket 1.
After cooling the stator coil 3b, it is discharged from the discharge vent 1b as shown by the arrow.

The second centrifugal fan 8b is taken in from the cooling air suction vent 2a of the rear brackets 1 and 2, and is connected to the semiconductor regulator 1.
0. After cooling the O-side radiation fins 13 and the ■-side radiation fins 14 of the three-phase aftereffect rectifier, the stator coil 3b is cooled and discharged from the discharge vent 2b as shown by the arrow.

Further, a fan guide 8 is provided between the centrifugal fan 8b and the three-phase full-wave rectifier, a minute gap is provided between the centrifugal fan 8b and the fan guide 18, and the fan guide 18 is connected to the three-phase full-wave rectifier. The fixing bolts 17a to 17d and the nut 19 are used to securely tighten the fixing bolts 17a to 17d. This bolt 17a~-17
d passes through holes provided in each of the wiring board 16 for connecting the diodes, the radiating fins 14 on the 1 side, the insulators 15a to 15d, and the radiating fins 13 on the e side, and is fixed to the rear bracket 2.

Further, a slip ring 12 is provided between the rotor 7 and the bearing 6 on the rotating shaft 4, and is supplied with a field current from a brush 11 and connected to a field coil 7d.

The three-phase full-wave rectifier has a circuit shown in FIG. 2, in which diodes 20a and 20b are disposed on the common ■ side radiation fin 14 on the cathode side.

20d, diodes 21a and 21b disposed on the e-side radiation fin 13 with the anode side in common;

A total of 8 diodes, including 6 main rectifier diodes 21d and 2 similarly arranged neutral point diodes 20c and 21c, are connected to each phase, U, V, W, and neutral point of the stator coil 3b. ing'. This neutral point diode is well known as shown in Japanese Patent Publication No. 4451/1983.
It uses fluctuations in the neutral point voltage to reduce the output to DC output. The auxiliary rectifier diodes 22a to 22c have anode sides U and V.

It is connected to the W phase and the cathode side is common (indicated by L in the figure), and a field current is supplied from this L point to the field coil 7d.

FIG. 3 shows this three-phase full-wave rectifier as seen from the pulley side, and FIG. 4 shows it as seen from the side opposite to the pulley. This wiring board 16 is made of an insulating material, and has wiring terminals 23 inside.
a to 23d, and the L terminal 24 are buried.

The wiring terminals 23a, 23b, 23d are respectively U,
The V and W phases are connected to each main rectifier diode and auxiliary rectifier diode, and the terminal 23c connects the N phase and the main rectifier diode, and the L terminal 24 connects the cathodes of the auxiliary rectifier diodes 22a to 22c. ing. Here, main rectifier/neutral point diodes 20a to 20d, 21a to 2
Since large current flows through 1d, all the heat radiation fins 14. ○
Although the auxiliary rectifier diodes 22a to 22c are disposed on the side heat dissipating fins 3 and are cooled, lead-type glass diodes as shown in the figure are generally used as the auxiliary rectifying diodes 22a to 22c require a small current.

The e-side radiation fins 13 and the ■-side radiation fins 14 are horse-shaped with an arcuate inner layer, facing the inner surface of the rear bracket 2, and are attached to the fixing bolts 17a to 1.
7d are similarly arranged in an arc shape at certain intervals.

A line OP connecting the center of the fixing bolt 17a and the center O of the arc
Assuming that the center axis is the center axis, the auxiliary rectifier diode 22a is arranged parallel to the center axis OP, and the ■ side main rectifier diode 20a and the θ side main rectifier diode 21a are arranged on the opposite side to the center axis OP. Main rectifier diode 20a
, 21a center 0. R is the center 0' of the fixing bolt 17a
They are more equidistant. When vibration is applied to this full-wave rectifier and the cooling fins vibrate, the center ○' becomes a node of vibration, so it is mechanically stable, and the main rectifier diodes 20a and 21a mentioned above are connected to the center 0'. Since they are more equidistant, the phase difference in vibration becomes smaller, and vibration resistance can be improved. In addition, since the connection part between the cathode side of the auxiliary rectifier diode and the L terminal 24 protrudes toward the inner circumferential side of the cooling fin, it is exposed to the cooling air flowing in from the rear bracket, which increases the temperature of the auxiliary rectifier diode. width is reduced. Also, according to this structure, there are auxiliary rectifier diodes around the center O'.

Since the main rectifier diode can be arranged in a small space, the overall shape can be made compact.

〔Effect of the invention〕

According to the present invention, it is possible to arrange the main rectifier diodes and the auxiliary rectifier diodes in a concentrated manner around the fixing bolts, thereby making it possible to provide a compact three-phase aftereffect rectifier with excellent vibration resistance and high cooling efficiency.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional side view of a vehicle alternator according to the present invention;
FIG. 2 is a circuit diagram of a three-phase full-wave rectifier, FIG. 3 is a plan view of a diode section according to the present invention viewed from the pulley side, and FIG. 4 is a plan view similarly viewed from the opposite pulley side. Explanation of symbols 13...θ side heat radiation fin, 14°...■side heat radiation fin, 15a to 15d...insulator, 16...distribution board, 1
7a to 17d--Fixing bolts, 20a, 20b. 20d...+ side main rectifier diode, 21a. 21b, 21d... - side main rectifier diodes. 20c, 21c...neutral point diode, 22a-81
Figure 2 Hard f; 354 Zυ9 Z3b Figure 4

Claims (1)

[Claims] A pair of horse-shaped cooling fins having an arcuate inner and outer periphery and a plurality of diodes of different polarity arranged in the same direction on one side of each cooling fin, the pair of cooling fins being insulated from each other. In a diode structure held at multiple fixed points, the center axis is a line connecting each of the fixed points and the center of the arc, and an auxiliary rectifier diode is connected to one side of the fin along the center axis. An alternating current generator for a vehicle, characterized in that the pair of diodes of different polarity are arranged on the other side so as to be substantially parallel to each other, and on the other side, the pair of diodes of different polarity are arranged so as to be approximately equidistant from the fixed point.