JP2001169510A - Ac power generator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an AC power generator for a vehicle, which has improved heat radiating capability in a rectifying device. SOLUTION: In a rectifying device of an AC power generator, fins 11, 21 in the shape radially extending toward the external circumference side from the rotating shaft side are provided at the surface of a positive side heat sink 10 and negative side heat sink 20 opposing to an absorbing window, and the holes 1a, 2a are bored to each heat sink 10, 20. Accordingly, the cooling wind flows smoothly through the fins 11, 21 and through-holes 1a, 2a with the mutual effect of the radial fins 11, 21 and through-holes 1a, 2a, and thereby the cooling performance can be improved without increase of air flow resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular alternator mounted on an automobile or the like, and more particularly, to a vehicular alternator having a built-in rectifier with improved cooling efficiency.

[0002]

2. Description of the Related Art In recent years, the electric load of a vehicle has been increasing year by year due to the sophistication of the vehicle, and a higher output of an AC generator for a vehicle has been demanded. It is necessary to reduce the temperature of the heat radiating plate, since this leads to an increase in the temperature of the device.

In order to cope with the high temperature of the rectifier, for example, according to Japanese Patent Application Laid-Open No. H10-56760, a through hole is provided in a radiator plate near the outer periphery of the rectifier to directly apply cooling air to the rectifier to reduce the cooling effect. Enhancing structures are known.

[0004]

However, since most of the heat generated from the rectifier is conducted to the heat radiator immediately after the heat is generated, it is not sufficient to simply cool the rectifier directly. Unless the heat radiation performance is improved, it is difficult to further increase the cooling efficiency.

An object of the present invention is to provide a vehicular AC generator capable of further improving the heat radiation performance of a rectifier in view of the above points.

[0006]

In order to solve the above-mentioned problems, the present invention employs the technical means described in claims 1 to 5.

According to the first aspect of the present invention, since the fins (11, 21) are provided on the surface of the radiator plate (10, 20) and the through holes (1a, 2a) are provided, the radiator plate (10, 20) is provided. , 20), and the ventilation of the cooling air is improved as compared with the case where the through holes (1a, 2a) are not formed in the heat radiating plates (10, 20), and the cooling air flows through the fins (11, 21). And the rectifier (3) is actively cooled,
As a result, the heat dissipation performance of the rectifier (B) is greatly improved.

According to the second aspect of the present invention, since the heat radiating plates (10, 20) are mounted substantially perpendicular to the flow of the cooling air, the cooling air passing through the through holes (1a, 2a) is provided. The flow becomes smoother and the amount of cooling air increases, so that the heat radiation performance can be improved.

According to the third aspect of the present invention, since the fins (11, 21) have a shape that spreads radially from the rotating shaft (50) of the AC generator, the radiating area of the radiating plates (10, 20) is reduced. Heat sink (10, 20)
The flow of the cooling air flowing from the center side toward the outer peripheral side becomes smooth, the ventilation resistance is greatly reduced, and the amount of cooling air increases, so that the heat radiation performance can be further improved.

According to the fourth aspect of the present invention, the plurality of through holes (1a, 2a) formed in the stacked heat radiating plates (10, 20) are arranged so that the cooling air flows. Flow through the fins (11, 21) of the heat radiating plates (10, 20) and perform effective cooling, so that the heat radiation performance can be greatly improved.

According to the fifth aspect of the present invention, the through holes (1a, 2a) of the heat radiating plates (10, 20) of the laminated structure are provided at positions shifted with respect to the flow direction of the cooling air. The cooling air flows through the fins (1) of the radiator plates (10, 20).
1, 21), and it provides effective cooling.
The heat radiation performance can be greatly improved. For example, the flow direction of the cooling air can be grasped as the axial direction of the automotive alternator, and the through holes can be provided radially or circumferentially offset.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an alternator for a vehicle according to an embodiment of the present invention;
Will be described with reference to FIGS.

FIG. 1 is a partial side sectional view showing the entire structure of the alternator of the present embodiment, and shows the structure of an alternator having a built-in cooling fan as an example. The alternator A shown in FIG.
1, brush device 42, rectifier B, IC regulator 4
3, a drive frame 44, a rear frame 45, a pulley 46, and the like.

The rotor 40 is a rotor of an alternator A, which is a synchronous generator, and has a rotor coil 47 in which an insulated copper wire is wound cylindrically and concentrically, each having six claws. It has a structure in which it is sandwiched from both sides through a shaft 50 which is a rotation axis by pole cores 48 and 49. An axial-flow cooling fan 51 is attached to the end face of the pole core 48 on the front side (the pulley 46 side) by welding or the like in order to discharge the cooling air sucked in the axial direction from the front side in the axial direction and the radial direction. Installed and fixed. Similarly, a centrifugal cooling fan 52 is attached and fixed to the end face of the rear pole core 49 by welding or the like in order to radially discharge the cooling air sucked in from the rear side along the axial direction. Also, the shaft 5
0 are formed on the rear side of the rotor coil 47 with slip rings 53 and 54 electrically connected to both ends of the rotor coil 47.
Excitation current flows from the rectifier B to the rotor coil 47 by assembling it in a state where it is pressed against each of the coils 3 and 54.

The stator 41 is a stator of the alternator A, and a three-phase stator coil 5 is wound around a plurality of (for example, 36) slots formed in the stator core 57 at a predetermined interval.

The rectifier B is for rectifying a three-phase alternating current, which is an output voltage of the three-phase stator coil 5, to obtain a DC output. The heat radiating plate 10 includes a positive heat radiating plate 10 and a negative heat radiating plate 20 fixed at intervals, and a plurality of rectifiers 3 attached to the respective heat radiating plates by soldering. The heat radiating plates 10 and 20 are fixed so as to be substantially perpendicular to the flow of the cooling air introduced from the suction window 31. Details of the rectifier B will be described later.

The IC regulator 43 includes a rotor coil 47
When the load is light and the output voltage is high, the output voltage of the alternator A is kept constant by interrupting the application of the voltage to the rotor coil 47. The pulley 46 is for transmitting the rotation of an engine (not shown) to the rotor 40 in the alternator A, and is fastened and fixed to one end (the side opposite to the slip ring 53 and the like) of the shaft 50 by a nut 58. Further, a rear cover 30 is attached so as to cover the brush device 42, the rectifier B, and the IC regulator 43.

The alternator A having the above-described structure is
When rotation from the engine is transmitted to the pulley 46 via a belt or the like, the rotor 40 rotates in a predetermined direction. By applying an excitation voltage to the rotor coil 47 from the outside, the claw portions of the pole cores 48 and 49 are excited, and a three-phase AC voltage can be generated in the stator coil 5. Output current is taken out. The output voltage of the alternator A is the IC regulator 43
Is adjusted by

The rotation of the rotor 40 causes the cooling fan 51 attached to the end face of the pole core 48 to rotate.
Cooling air is sucked into the alternator A through the suction window near 6, and the rotor coil 47 is cooled by the axial component of the cooling air, and the pulley half of the stator coil 5 is cooled by the radial component. . Similarly, since the cooling fan 52 attached to the end face of the pole core 49 also rotates, the cooling air sucked through the suction window 31 of the rear cover 30 cools the rectifier B and the IC regulator 43, and then cools. The cooling air is guided to the vicinity of the fan 52, and the cooling air is discharged in the radial direction, so that the rear half of the stator coil 5 is cooled.

At this time, the through holes 1a, 2a provided in each of the laminated heat sinks (the heat sink 10 on the positive electrode side and the heat sink 20 on the negative electrode side) are provided.
However, the position of the cooling air is alternately shifted with respect to the flow direction along the substantially axial direction, and the cooling air flows through the through holes 1a,
Due to the fact that the cooling air passes alternately (in a zigzag shape), the contact time of the cooling air with each of the heat radiating plates 10 and 20 becomes longer, and the heat radiation performance can be improved.

FIG. 2 is a perspective view showing the detailed shape of the rectifier B described above. FIG. 3 is a sectional view taken along the line III-III in FIG. As shown in these figures, the rectifier B is
The positive-side radiator plate 10 and the negative-side radiator plate 2 having a predetermined interval in the rotation axis direction and partially overlapping each other in the radial direction.
It has 0. The outer diameter of the positive-side radiator plate 10 is set to be larger than the outer diameter of the negative-side radiator plate 20, and a part of the air introduced through the suction window 31 of the rear cover 30 passes through the negative-side radiator plate 20. While being guided to the positive-side heat sink 10, another part of the air is directly guided to the positive-side heat sink 10 without passing through the negative-side heat sink 20. An alternator A is provided on a part of the heat sink 10 on the positive electrode side.
An output terminal 32 for taking out the output from outside is mounted and fixed by press fitting or the like.

The positive-side heat sink 10 has four dents 33 to which the rectifier 3 is soldered in a concave portion. Similarly,
The negative-side heat sink 20 has four dents 34 to which the rectifier 3 is soldered. For example, each of these heat sinks 1
Reference numerals 0 and 20 are formed into a predetermined outer shape by molding (die-casting, sheet metal, or the like) a metal plate such as an aluminum plate or a copper plate having a predetermined plate thickness and having good heat conductivity. Although the number of the indentations 33 and 34 for installing the rectifier 3 formed on each of the heat radiating plates 10 and 20 is set to four, respectively, when three-phase alternating current generated in the stator coil 5 is rectified, three Since the rectifier 3 is sufficient, the number of the indentations 33 and 34 for installing the rectifier 3 may be set to three.

Further, the through holes 1a, 2a may be formed at the same time when the metal plate is formed, or may be formed by pressing or cutting.

The radiating fins 11 and 21 are provided on the surface of the positive-side radiator plate 10 and the negative-side radiator plate 20 on the side opposite to the suction window 31 for introducing the cooling air, on the outer circumferential side from the rotating shaft 50 side of the alternator A. It has a shape that expands radially toward. Thereby, the cooling air introduced from the suction window 31 flows smoothly from the center side toward the outer peripheral side, and the cooling air can be smoothly guided to the through holes 1a and 2a.

Next, the operation of the above configuration will be described.

1 to 3, the cooling air is sucked from the lower rear part of the alternator A shown in FIG. 1 and flows as indicated by the arrow by the rotation of the centrifugal cooling fan 52 fixed to the pole core 49 on the rear side. The cooling air flows along the side surfaces of the fins 21 protruding from the second-stage heat radiating plate 20, and a part of the cooling air flows through the through holes 2 a formed at substantially right angles to the second-stage heat radiating plate 20. In these processes, the second-stage radiator plate 20 is cooled. Further, the cooling air is supplied to the first-stage heat sink 1
The fins 11 flow along the side surfaces of the fins 11 protruding from the first radiating plate 10, and a part of the fins 11 penetrates the first-stage heat sink 10 at right angles.
Flow through. In these processes, the first-stage radiator plate 10 is cooled. The cooling air is bent in the outer circumferential direction by the cooling fan 7 as shown by the arrow, cools the stator coil 5 and is discharged to the outside of the vehicle alternator.

In FIGS. 2 and 3, two heat sinks 1
0 and 20 are stacked and a plurality of through holes 1a and 2a are formed in each of the heat radiating plates 10 and 20, so that the heat radiating area is increased, and the radial fins 11 and 21 and the plurality of through holes 1 and 2 are provided.
The interaction with the cooling air flows through the fins 11, 21 and the through holes 1a, 2a, whereby the flow of the cooling air becomes smooth, and the cooling performance can be improved without increasing the ventilation resistance so much.

Further, the two stacked heat sinks 10, 2
Since the plurality of through holes 1a, 2a formed in the hole 0 are alternately arranged so that the cooling air flows in a zigzag shape, the cooling air flows all over the fins 11, 21 of the radiating plates 10, 20, and the cooling air flows. Since the contact time with the heat radiating plate becomes longer, the cooling efficiency (radiation performance) is greatly improved.

In this embodiment, the fins are provided radially. However, the fins may be parallel and formed in a direction substantially along the flow of the cooling air flowing radially outward from the rotation shaft 50.

FIG. 4 shows an embodiment in which both the through-holes 1a and 2a provided in the positive-side radiator plate 10 and the negative-side radiator plate 20 are aligned so as to be linear with respect to the flow of cooling air. is there.

Since the cooling air flows linearly through the through holes 1a and 2a, the ability to cool the rectifier 3 is slightly reduced, but the flow of the cooling air is smoother and the ventilation resistance is lower than when the cooling air flows in a zigzag shape. Is reduced, the amount of cooling air can be increased, and both the improvement of the cooling performance of the rectifier B and the improvement of the cooling performance of the stator coil 5 can be achieved.

[Brief description of the drawings]

FIG. 1 is a partial side sectional view showing an entire structure of an alternator according to an embodiment of the present invention.

FIG. 2 relates to an embodiment of the present invention, and FIG.
It is the perspective view which took out and showed the rectifier inside.

FIG. 3 relates to an embodiment of the present invention, and FIG.
It is sectional drawing cut | disconnected by the cross section III-III in a middle.

FIG. 4 is a partial side sectional view showing a peripheral portion of a rectifier of an alternator according to another embodiment of the present invention.

[Explanation of symbols]

1a, 2a through hole 3 rectifier 10, 20 radiator plate (10: positive-side radiator plate, 20: negative-side radiator plate) 11, 21 fin 31 suction window 50 rotation axis A vehicle alternator B rectifier

Claims (5)

[Claims] A rectifier (1) including a radiator plate (10, 20) mounted in a flow of cooling air, and a rectifier (3) mounted on one surface of the radiator plate (10, 20). B) The automotive alternator provided with B), wherein fins (11, 2) are provided on the surface of the heat sink (10, 20).
An alternator for a vehicle, wherein 1) is provided and through holes (1a, 2a) are provided. 2. The vehicle alternator according to claim 1, wherein the heat radiating plates are mounted substantially perpendicular to the flow of the cooling air. 3. The alternating current for a vehicle according to claim 1, wherein the fins (11, 21) have a shape extending radially from a rotating shaft (50) of the alternator. Generator. 4. The radiator plate (10, 20) has a positive-side radiator plate (10) and a negative-side radiator plate (20), and each of the radiator plates (10, 20) has the through hole (1a, 2a). The alternator for a vehicle according to any one of claims 1 to 3, wherein a plurality of the heat radiating plates (10, 20) are stacked to form a laminated structure. 5. Each of the heat sinks (10, 20) having a laminated structure.
The vehicle alternator according to claim 4, wherein the through holes (1a, 2a) are provided at positions shifted with respect to the flow direction of the cooling air.