JPH1056760A - Ac generator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an AC generator, for a vehicle, in which the cooling efficiency of a rectifying device can be enhanced by directly cooling a rectifying element. SOLUTION: An embossed part 57 which is formed on every heat sink 53 of a rectifier as a rectifying device has a conical trapezoid shape, and four through holes 59 which are used as ventilation ports are formed in parts of a slope as a side face. A rectifying element 55 is attached to a flat face in a recess on the backside of the embossed part 57 so as to sandwich a copper plate 61. Since each of the four through holes 59 is formed so as to pass a part of the slope at the embossed part 57, a part of a cooling wind W which is introduced via an intake window in a rear cover flows to the backside of the heat sink 53 through the through holes 59, and a part flows along the surface of the heat sink 53. The rectifying element 55 is cooled directly by the cooling wind W which flows to the backside of the heat sink 53.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art A vehicular alternator performs auxiliary charging of a battery while the vehicle is running, as well as ignition, lighting,
It supplies the power of various other electrical components, and in order to maintain or improve market competitiveness, reduction in size, weight, output, and cost are important issues. Among these problems, as one of means for achieving reduction in size and weight and cost reduction, a method of changing the material of a radiator plate of a rectifier installed in a vehicle alternator from copper to aluminum is known. I have. However, since aluminum has a higher electrical resistance and a lower heat transfer coefficient than copper, changing the heat sink from copper to aluminum while maintaining the conventional shape may increase the temperature. Needs to be reduced.

In recent years, the trend of electric loads on vehicles has been increasing year by year due to the sophistication of vehicles and the like, and it is required to increase the output of AC generators for vehicles. Since the temperature of the rectifier rises, it is necessary to reduce the temperature of the heat sink not only when the heat sink is made of aluminum but also when it is made of copper.

As a conventional technique for reducing the temperature of the heat radiating plate of the rectifier, there is a rectifier disclosed in Japanese Patent Application Laid-Open No. 1-99460. This rectifying device is provided with a cut-and-raised portion opened on the lead side of the rectifying element in a part of the radiator plate, so that the lead projecting to the back side of the radiator plate is directly cooled by cooling air. Another conventional technique is a rectifying device described in German Patent No. 294,693. In this rectifying device, a cooling heat is introduced into the rectifying element side by increasing the surface area by bending an outer peripheral portion of a fan-shaped heat radiating plate in a rotation axis direction and providing cutouts at several corners thereof. Also, as another conventional technology,
There is a rectifying device described in U.S. Pat. No. 4,701,828. This rectifying device cuts and raises a part of the radiator plate along the outer circumference of the rectifier element and presses the cut and raised surface against the rectifier element, and through a through hole generated by partially cutting and raising the radiator plate. A cooling air is introduced.

[0005]

The rectifier described in Japanese Patent Application Laid-Open No. 1-99460 directly cools the leads of the rectifying element. However, since the surface area of the leads themselves is small, the cooling efficiency is reduced. May not be so high. A cut-and-raised portion is provided in the vicinity of the rectifying element, but the fan of the automotive alternator shown in FIG. In this case, since most of the cooling air flows in the rotation axis direction, there is a possibility that the cooling air does not sufficiently hit the leads and the cooling efficiency does not increase.

[0006] Also, the above-mentioned German Patent No. 29426.
In the rectifier described in No. 93, cooling air can be introduced to the back side of the radiator plate by several cutouts provided at the outer peripheral corners of the radiator plate, as shown in FIGS. 1 and 3. Since the plurality of notches are merely arranged at appropriate intervals, there is a possibility that the rectifying element having the highest temperature cannot be efficiently cooled.

In the rectifier described in US Pat. No. 4,701,828, the cut surface is first cooled by cooling air introduced through a through hole formed by cutting and raising a heat sink. The cooling efficiency may be reduced as compared with the case where the rectifying element having the highest temperature is directly cooled.

The present invention has been made in view of the above points, and an object of the present invention is to provide a vehicular AC generator capable of improving the cooling efficiency of a rectifier by directly cooling a rectifier. Is to do.

[0009]

According to the present invention, one or a plurality of through holes are formed in a radiator plate of a rectifier at a position where the rectifier is mounted so as to substantially contact the outer periphery of the rectifier. A part of the cooling air sucked into the rectifier from the inlet window of the generator directly hits the rectifier element body, which is attached to the back side of the radiator plate by soldering, etc., so that the rectifier element, which is a heat source, is efficiently cooled. can do.

In particular, when a truncated-cone-shaped projection for attaching a rectifying element is provided on a heat sink, and a through-hole is formed at an inclined position on the side surface, the through-hole and the rectifying element body approach each other. It is easy to directly apply a part of the element to the rectifying element body.

[0011] In the above various rectifiers,
A metal plate may be interposed between the radiator plate and the rectifying element, and the metal plate may face the through hole.
For example, if the material of the heat sink is aluminum,
It is conceivable to attach a copper plate to the surface of this heat sink and solder a rectifier to the surface.If this copper plate is made to face the through hole, the rectifier, which is a heat source than the heat sink, can be considered. Since the copper plate close to the element is cooled, the temperature of the entire rectifier can be reduced. The same effect can be obtained even when the above-described metal plate is interposed with the material of the heat sink made of copper.

In addition to forming a through hole,
By inclining the outer edge of the through hole and away from the rectifying element so as to approach the rectifying element toward the downstream of the cooling air passing through the through hole, the flow of the cooling air flowing substantially perpendicular to the heat sink. Can be partially directed to the rectifying element body. Alternatively, the amount of cooling air flowing to the rectifying element side can be increased by forming a convex-shaped partition on the outer side of the through hole and away from the rectifying element to increase the opening area. Thus, the rectifying element body, which has a higher temperature than the heat sink, can be efficiently cooled.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicular alternator (hereinafter referred to as an "alternator") of the present invention is characterized in that the cooling performance is improved by devising the shape of a rectifier as a rectifier. . Hereinafter, an alternator according to one embodiment to which the present invention is applied will be specifically described with reference to the drawings.

FIG. 1 is a partial cross-sectional view showing the entire structure of the alternator according to the present embodiment. As an example, the structure of an alternator incorporating a cooling fan is shown. The alternator 1 shown in FIG. 1 includes a rotor 2, a stator 3, a brush device 4, a rectifier 5, an IC regulator 6, a drive frame 7, a rear frame 8, a pulley 9, and the like.

The rotor 2 is a rotor of the alternator 1 which is a synchronous generator, and has a rotor coil 21 in which an insulated copper wire is wound cylindrically and concentrically, each having six claws. The pole cores 22 and 23 have a structure sandwiched from both sides through a shaft 24 which is a rotation axis. An axial-flow-type cooling fan 25 is attached and fixed to the end face of the pole core 22 on the front side (the pulley 9 side) by welding or the like to discharge the cooling air sucked from the front side in the axial direction and the radial direction. . Similarly, a centrifugal cooling fan 26 is attached and fixed to the end face of the rear pole core 23 by welding or the like in order to radially discharge the cooling air sucked in from the rear side.
Slip rings 27 and 28 electrically connected to both ends of the rotor coil 21 are formed on the rear side of the shaft 24, and the brushes 41 and 42 in the brush device 4 are attached to the slip rings 27 and 28, respectively. By assembling in a pressed state, an exciting current flows from the rectifier 5 to the rotor coil 21.

The stator 3 is a stator of the alternator 1, and three-phase stator coils 32 are wound around a plurality of (for example, 36) slots formed in the stator core 31 at predetermined intervals.

The rectifier 5 is for rectifying a three-phase AC, which is an output voltage of the three-phase stator coil 32, to obtain a DC output. The heat radiating plate 52 includes a positive heat radiating plate 52 and a negative heat radiating plate 53 fixed at intervals, and a plurality of rectifying elements 54 and 55 attached to the respective heat radiating plates by soldering. The details of the rectifier 5 will be described later.

The IC regulator 6 includes a rotor coil 21
When the load is light and the output voltage is high, the output voltage of the alternator 1 is kept constant by interrupting the application of the voltage to the rotor coil 21. The pulley 9 is for transmitting the rotation of an engine (not shown) to the rotor 2 in the alternator 1, and is fixedly fastened to one end of the shaft 24 (opposite to the slip ring 27 and the like) by a nut 91. . Also, a brush device 4, a rectifier 5
And a rear cover 92 covering the IC regulator 6.
Is attached.

The alternator 1 having the above-described structure includes:
When the rotation from the engine is transmitted to the pulley 9 via a belt or the like, the rotor 2 rotates in a predetermined direction. By applying an excitation voltage to the rotor coil 21 from the outside, the claw portions of the pole cores 22 and 23 are excited, and a three-phase AC voltage can be generated in the stator coil 32. A predetermined voltage is output from the output terminal of the rectifier 5. Output current is taken out. Thereafter, since the output voltage of the alternator 1 itself is applied to the rotor coil 21 via the IC regulator 6, an externally applied excitation voltage is not required.

Further, with the rotation of the rotor 2 described above,
Cooling fan 25 attached to the end face of pole core 22
, The cooling air is sucked into the alternator 1 through the suction window near the pulley 9 of the drive frame 7, and the axial component of the cooling air causes the rotor coil 21 to rotate.
Is cooled, and the pulley side half of the stator coil 32 is cooled by the radial component. Similarly, the cooling fan 26 attached to the end face of the pole core 23 also rotates, so that the cooling air sucked through the suction window of the rear cover 92 cools the rectifier 5 or the IC regulator 6 and then closes the cooling fan 26. The cooling air is discharged in the radial direction, and the rear half of the stator coil 32 is cooled.

FIG. 2 is a plan view showing the detailed shape of the rectifier 5 described above. FIG. 3 is a partially enlarged cross-sectional view of the alternator 1 including the rectifier 5, and shows a cross-sectional structure near the rear cover 92 and the rectifier 5 shown in FIG. As shown in these figures, the rectifier 5 has a positive-side radiator plate 52 and a negative-side radiator plate 53 having a predetermined interval in the rotation axis direction and having an arc shape partially overlapping with each other in the radial direction. ing. The outer diameter of the heat sink 52 on the positive electrode side is set to be larger than the outer diameter of the heat sink 53 on the negative electrode side, and a part of the air introduced through the suction window of the rear cover 92 passes through the heat sink 53 on the negative electrode side. While being guided to the side heat radiating plate 52, it is directly guided to the positive electrode side radiating plate 52 without passing through the negative electrode side radiating plate 53. Further, an output terminal 69 for taking out the output of the alternator 1 to the outside is mounted and fixed to a part of the positive electrode side heat sink 52 by press fitting or the like.

The heat sink 52 on the positive electrode side has a rectifying element 54
Have four embossed portions 56 soldered.
Similarly, the negative side heat sink 53 is provided with the rectifying element 5
5 has four embossed portions 57 to be soldered. For example, each of the heat radiating plates 52 and 53 is formed into a predetermined external shape by pressing an aluminum plate having a predetermined thickness, and each embossed portion 56 and 57 is formed by extruding a part thereof. Is done. Although the number of the embossed portions 56 and 57 formed on each of the heat radiating plates 52 and 53 is four, three rectifying elements 54 and 55 are used to rectify the three-phase AC generated by the stator coil 32. Is sufficient, the number of the embossed portions 56 and 57 may be set to three each.

FIG. 4 is a diagram showing a detailed shape of one of the embossed portions 57 extracted. FIG. 7A is a plan view of the embossed portion 57, and FIG.
FIG. 4 is a sectional view taken along line IV. The embossed portion 56 has the same detailed shape, and the embossed portion 57 will be described as a representative.

The embossed portion 57 is formed as a truncated cone-shaped convex portion, and four through holes 59 serving as ventilation holes are formed at inclined positions on the side surfaces thereof. Each through hole 5
9 is formed by, for example, punching out the embossed portion 57 with a press device when extruding the embossed portion 57. Alternatively, the through holes 59 may be formed by cutting.

A rectifying element 55 is mounted on the flat surface of the concave portion on the back side of the embossed portion 57 with a copper plate 61 as a metal plate interposed therebetween. In general, it is not easy to solder the case 55a of the rectifying element 55 made of copper to the heat radiating plate 53 made of an aluminum plate. In this embodiment, the copper plate 61 is ultrasonically welded to the surface of the heat radiating plate 53. And a rectifying element 5 on the surface.
The fifth case 55a is soldered. As described above, the rectifying element 55 is soldered to the flat surface of the concave portion on the back side of the embossed portion 57 with the copper plate 61 interposed therebetween, so that the rectifying element 5
5 and the radiator plate 53 are in good electrical contact with each other,
The heat generated by the rectifying element 55 is efficiently transmitted to the heat radiating plate 53 via the copper plate 61.

As described above, since each of the four through holes 59 is formed so as to penetrate a part of the inclined surface of the embossed portion 57, the cooling air introduced through the suction window of the rear cover 92 is provided. As shown in FIG. 3 and FIG. 4B, the wind W partially flows to the back side of the heat radiating plate 53 through the through hole 59 and partially flows along the surface of the heat radiating plate 53. Therefore, the heat radiating plate 53 itself is cooled by the cooling air W flowing along the surface of the heat radiating plate 53, and the rectifying element 55 is directly cooled by the cooling air W flowing to the back side.

The case 55a of the rectifying element 55 and the lead 55
b is generally formed of copper having a small electric resistance,
Since the thermal conductivity is large, if these can be directly cooled, the rectifying element 55 which is one of the heat sources can be efficiently cooled. Particularly, as shown in FIG. 4B, the outer diameter of the flat surface on the back side of the embossed portion 57 and the rectifying element 5
In the case where the outer diameter of the case 55a is substantially the same as that of the case 55, the case 55a and the through hole 59 have a very close positional relationship, and therefore the cooling air introduced through the through hole 59. The case 55a, which is heated to a high temperature by W, can be efficiently cooled.

In some cases, the rectifier 5 is painted for the purpose of preventing corrosion. However, the rectifier 5 of the present embodiment is provided with a plurality of through holes 5 in the embossed portions 56 and 57.
8 and 59, the coating can be easily turned on the back side (the side where the rectifying elements 54 and 55 are attached) of each radiator plate 52 and 53 of the rectifier 5 to prevent uneven coating. Can be. In particular, when powder coating is performed on a conventional rectifier, powder coating has lower fluidity than liquid coating. Therefore, as shown in FIG. Is soldered, it is not easy to sufficiently penetrate the coating powder into the gap near the outer periphery of the copper plate 61, but as in the present embodiment, a through hole 59 is formed near the outer periphery of the copper plate 61. By forming the powder, the powder can easily flow around this portion, so that the occurrence of uneven coating can be suppressed.

As can be seen from the cross-sectional structure of the rectifier 5 shown in FIG. 3, the rectifier 5 has a complicated shape, and conventionally, the back side of each of the heat radiating plates 52 and 53, particularly the rectifying element 54, Although muddy water, rainwater, and the like are likely to stay around 55, in the present embodiment, the through holes 58, 59 are formed at positions near the rectifying elements 54, 55 to prevent such various liquids from staying. There is also an effect.

FIG. 5 is a diagram showing a modification of the above-described embodiment. FIG. 7A is a plan view showing one of the embossed portions 57, and FIG. 7B is a sectional view taken along line VV. The difference from the structure near the embossed portion 57 shown in FIG. 4 is that the copper plate 61 is replaced with a copper plate 62 in which the shape is partially changed. That is, the copper plate 61 shown in FIG. 4 has a circular shape having substantially the same outer diameter as the case 55a of the rectifier element 55, and is used for the purpose of facilitating the soldering of the rectifier element 55. On the other hand, the copper plate 62 shown in FIG. 5 has a shape in which the outer diameter portion corresponding to the through hole 59 is extended outward, so that the rectifying element 55 can be easily soldered and the cooling air W By projecting this extended portion into the ventilation path, the cooling efficiency can be further increased. More specifically, the copper plate 62 is slightly smaller than the flat surface on the back side of the embossed portion 57 and slightly larger than the bottom surface of the case 55a of the rectifying element 55.
And four arm portions 62 b extending in four directions from the joining portion and directly facing the through holes 59. Moreover, these arms 62b are located on the axial direction of the through hole 59 so that they can be directly viewed through the through hole 59.

In particular, since the temperature of the copper plate 62 closer to the rectifying element 55, which is the heat source, is higher than that of the heat radiating plate 53, the temperature difference between the copper plate 62 and the cooling air W increases, and the amount of heat radiation increases.
Further, as shown in FIG. 5B, the copper plate 62 can protrude into the through hole 59 only by extending the outer diameter portion thereof, so that the cooling efficiency of the copper plate 62 can be increased, and the copper plate 61 can be further improved. When replacing with the copper plate 62, it is only necessary to change the shape of the punching die,
An increase in manufacturing cost can be minimized.

FIG. 6 is a view showing a modification of the through hole provided on the inclined surface of the embossed portion. In the above-described example, a part of the radiating plate 53 punched out as a guide plate for introducing the cooling air W is used. The case where it was used is shown. FIG. 7A is a plan view showing one of the embossed portions 57, and FIG. 7B is a sectional view taken along line VI-VI of FIG. Fig. (B)
As shown in FIG.
Is inclined toward the downstream of the flow of the cooling air W passing through the through hole 59 so as to approach the rectifying element 55, so that the inclined portion is used as a guide plate 65 for the cooling air W. Can be positively directed to the case 55a and the lead 55b of the rectifying element 55. In particular, in the structure shown in FIG. 4, a part of the heat radiating plate 53 is removed by punching or cutting to form the through hole 59, but in the structure shown in FIG.
The guide plate 65 is formed by bending along one side of the outer peripheral side of the through hole 59 and inclining it to the rear side (the side where the rectifying element 55 is mounted) of the heat radiating plate 53 without removing a part of 3. And effective cooling of the rectifier element 55 can be realized.

FIG. 7 is a diagram in which the shape around the embossed portion shown in FIG. 6 is further modified. FIG. 7A shows one planar shape of the embossed portion 57, and FIG. Indicates a cross section taken along the line VII-VII. The point that a part of the heat radiating plate 53 is bent to function as a guide plate 65 for introducing the cooling air W is the same as the structure of the embossed portion 57 shown in FIG. Extrusion by press is performed on the outer periphery of 59 to form a convex partition 63 along the outer periphery of the arc shape.
For example, the partition portion 63 is formed in a convex shape by pressing and deforming a part of the heat radiation plate 53 on the outer peripheral side further by extrusion molding by a press to cause a change in thickness. The cooling air W flowing on the surface of the heat sink 53 by the partition 63
Is taken into the through hole 59, and the opening area for introducing the cooling air W to the rectifying element 55 side can be substantially enlarged.

FIG. 8 is a view showing another modification in which the opening area for introducing the cooling air W is enlarged. FIG. 8A shows one of the embossed portions 57 in a plan view. B) shows a section taken along line VIII-VIII. FIG.
In the structure shown in FIG. 8, the guide plate 65 is formed simply by inclining the edge of the through hole 59 on the side remote from the rectifying element 55, but in the structure shown in FIG. By cutting and raising the outside of the connecting portion 67 formed at a position where the inclined surface of the embossed portion 57 and the heat radiating plate 53 intersect with each other at the edge of the through hole 59 on the side remote from 55, the diameter of the outer peripheral portion is reduced. A large guide plate 66 is formed. Also, the guide plate 66 inside the connecting portion 67
The rectifying element 55 side is inclined so as to approach the rectifying element 55 toward the downstream of the flow of the cooling air W passing through the through hole 59, similarly to the guide plate 65 shown in FIG. Therefore,
The flow of the cooling air W passing through the through hole 59 is positively
5 can be directed to the case 55a and the lead 55b, and by increasing the diameter of the outer periphery, the opening area for introducing the cooling air W to the rectifying element 55 side can be substantially enlarged.

By increasing the opening area for introducing the cooling air W by the structure shown in FIG. 7 or FIG. 8, the cooling air guided to the back side of the embossed portion 57, that is, to the case 55a and the lead 55b of the rectifying element 55. Since the flow rate of W increases, the temperature of the rectifying element 5 becomes higher than that of the heat sink 53.
5 can be efficiently cooled.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. For example, the rectifier 5 described above
Although the radiator plates 52 and 53 made of aluminum are used, a radiator plate made of copper may be used. However, in this case, the copper plate 61 shown in FIG.
The rectifying element can be directly soldered to the flat part on the back side of the embossed part. Also, as an example, the case where four through holes 59 are formed in each of the embossed portions 57 has been described, but the number and shape of the through holes 59 are determined in consideration of the temperature of the rectifying element, the material of the heat sink, and the like. May be changed as appropriate.

When the heat radiating plate 53 shown in FIG. 4 is formed by pressing an aluminum or copper plate material, the plate material corresponding to the through hole 59 is punched and removed. The thickness of the remaining inclined surface may be increased by causing a change in the thickness toward the inclined surface of the rectifying element 55 so that heat is easily transmitted from the rectifying element 55 to the heat sink 53. In particular, when the material is aluminum, the malleability and ductility are good, so that the wall thickness can be easily changed, and the above-described processing is easily performed.

Further, the cooling fins may be formed by partially extruding the remaining inclined surface having the increased thickness. FIGS. 9A and 9B are views showing the structure near the embossed portion 57 in which the cooling fin 64 is formed on the inclined surface. FIG. 9A is a plan view, and FIG. 9B is a sectional view taken along line IX-IX. Is shown. As shown in these figures, the cooling fins are directed toward the heat sink 53 from the end of the convex flat surface of the embossed portion 57 by utilizing the thickness moved to the adjacent inclined surface when the through hole 59 is formed. Since the surface area of the heat radiating plate 53 is increased by forming the heat sink 64, the cooling efficiency can be further increased. In particular, as shown in FIG.
When the cooling fins 64 are formed substantially radially from the center of the convex flat surface of the embossed portion 57, the cooling fin flows from the flat flat surface to the surface of the heat radiating plate 53 through the through holes and to the rectifying element 55. Since the cooling air is not blocked, the amount of the cooling air does not decrease.

In the above description of the embodiment, it is assumed that the heat radiating plate 53 and the like are formed by using an aluminum plate material. The copper plate 61 is attached to the surface, and the rectifying element 55 is further soldered to the surface. However, when the rectifying element 55 is directly attached to the heat radiating plate 53 by soldering or other methods, or when the heat radiating plate 53 is When formed of copper, the copper plate 61 may be removed. Alternatively, the heat sink 53 may be formed of copper, and the copper plate 62 may be added.

In the above description of the embodiment, the four embossed portions 56, 57 are provided on the heat radiating plates 52, 53, respectively.
Are formed, and the rectifying elements 54 and 55 are attached to the recesses by soldering or the like.
The present invention can also be applied to a rectifier having a radiator plate having no radiator 7, that is, a rectifier in which a rectifying element is attached directly to a radiator plate having no unevenness or a copper plate is interposed. In this case, instead of forming a through-hole serving as a ventilation port on the inclined surface of the embossed portion, one or a plurality of through-holes are formed so as to substantially contact the outer periphery of the case of the rectifying element.
By forming the through hole at a position very close to the rectifying element in this way, the cooling air flowing through the through hole to the backside of the rectifier flows along the case of the rectifying element. Can be directly cooled. Further, the copper plate 62 having the shape shown in FIG.
When a copper plate is used, a part of the copper plate 62 is exposed to the through hole, so that the copper plate 62 can be efficiently cooled. When a part of the heat sink is bent or a partition is formed as shown in FIGS. 6 to 8, it is necessary to change the direction of the cooling air passing through the through-holes and more directly apply the heat to the rectifying element. Alternatively, it is possible to increase the air volume by increasing the opening area.

Further, in the above-described embodiment, the internal fan type alternator 1 in which the cooling fan is built in the frame as shown in FIG. 1 has been described as an example, but the external fan in which the cooling fan is attached to the end surface of the pulley is described. The present invention can be applied to an alternator of the formula.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of an alternator to which the present invention is applied.

FIG. 2 is a plan view showing a detailed shape of a rectifier as a rectifier.

FIG. 3 is a partially enlarged cross-sectional view of an alternator near a rectifier.

FIG. 4 is a diagram showing a detailed structure of an embossed portion formed in the rectifier.

FIG. 5 is a view showing a modified example of an embossed portion formed in a rectifier.

FIG. 6 is a view showing another modification of the embossed portion formed in the rectifier.

FIG. 7 is a view showing another modified example of an embossed portion formed on a rectifier.

FIG. 8 is a view showing another modified example of an embossed portion formed on a rectifier.

FIG. 9 is a view showing another modified example of an embossed portion formed in a rectifier.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Alternator 2 Rotor 3 Stator 4 Brush device 5 Rectifier 51 Terminal block 52, 53 Heat sink 54, 55 Rectifier element 56, 57 Embossed part 58, 59 Through-hole 61, 62 Copper plate

Claims (5)

[Claims] 1. A radiator plate mounted substantially perpendicular to the flow of cooling air introduced through a suction window, and a rectifying element mounted on one surface of the radiator plate and opposite to the suction window. In a vehicle alternator having a built-in rectifier device, one or more through holes are provided at a position where the rectifier element of the radiator plate is to be attached and almost in contact with an outer periphery of the rectifier element. Characteristic alternator for vehicles. 2. The method according to claim 1, wherein a truncated-cone-shaped protrusion is formed at a position where the rectifying element of the radiator plate is attached, so as to protrude toward the suction window, and the through hole is formed at an inclined position on a side surface of the protrusion. A vehicle alternator characterized by being provided. 3. The alternating current for a vehicle according to claim 1, wherein a metal plate is interposed between the radiator plate and the rectifying element, and the metal plate is arranged to face the through hole. Generator. 4. The piercing device according to claim 1, wherein an edge of the through hole on a side remote from the rectifying element is inclined toward the downstream of the flow of the cooling air so as to approach the rectifying element. An alternating current generator for a vehicle, wherein the flow of the cooling air passing through the hole is directed to the rectifying element. 5. The rectifying device according to claim 4, wherein an opening area of the cooling air flowing toward the rectifying element is increased by forming a convex-shaped partition on an outer periphery of the through-hole remote from the rectifying element. An alternator for a vehicle, characterized in that: