JP2004312852A - Rotary electric machine for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To offer a rotary electric machine for a vehicle which raises the heat radiation property of a power semiconductor element and a power module. <P>SOLUTION: In the rotary electric machine for a vehicle, a fan 11 is attached to the end of the rotor 3. A power module (including a power semiconductor element) 14 for power is attached to a bracket 10, which holds this rotor and constitutes the housing of the rotary electric machine, directly or through a heat conductive member 23, with the heat radiation face on the mounting side of the power module being directed toward the bracket 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a heat dissipation structure of a power semiconductor element of a rotating electrical machine for a vehicle, and more particularly, to a rotating electrical machine mounted with a power semiconductor element for electric power (for example, a rectifying element, a voltage regulator, a power converter, etc.).
[0002]
[Prior art]
Patent Literature 1 discloses an electronic component (such as a capacitor or a transistor) of an automatic voltage regulator of a vehicle generator, which is modularized on a substrate, and the substrate is fixed to an outer surface of a rear bracket of the generator. . The board is a printed board made of resin, and has a structure mounted away from the bracket surface.
[0003]
Patent Literature 2 discloses a generator in which a voltage regulator (a rectifier having a power transistor as a semiconductor rectifier incorporated in a case) is fixed to an outer surface of a generator housing (rear bracket). In the voltage regulator in this case, the case and its lid form cooling fins, and the voltage regulator is fixed to the inner surface of the lid. Therefore, the heat generated from the power semiconductor rectifier of the voltage regulator is transmitted from the lid to the rear bracket via the case and radiated, and a part of the heat is radiated into the air.
[0004]
[Patent Document 1]
JP-A-9-331654 [Patent Document 2]
JP-A-8-336258
[Problems to be solved by the invention]
In the field of rotating electric machines for vehicles, as described above, a voltage regulator and a power element such as a diode are mounted on a bracket of a generator (for example, an alternator). However, from the viewpoint of the environment, the need to stop the engine idling has led to the development of a motor generator that has both functions of driving and power generation with a single rotating electric machine. It is also being studied to mount it on a rotating electric machine (motor, generator) as a power module.
[0006]
In such a tendency, it is desired to improve the heat radiation of the power module of the rotating electric machine with an increase in the capacity of the rotating electric machine.
[0007]
SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a rotating electric machine for a vehicle in which the heat dissipation of a power semiconductor element and a power module is improved as compared with the related art.
[0008]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION In order to achieve the above object, the present invention basically provides a rotating electric machine for a vehicle configured as follows.
[0009]
One is a rotating electric machine for vehicles,
A fan is attached to an end of the rotor, and a bracket that holds the rotor and forms a housing of the rotating electric machine has a power semiconductor element for electric power, and a heating surface on a mounting side of the power semiconductor element on the bracket. Is mounted directly or via a heat transfer member.
[0010]
For example, in a rotating electric machine for a vehicle, a power module (or a rectifier diode such as an alternator) having a semiconductor element for power, an insulating substrate, and a heat sink is mounted on an outer surface of a bracket serving as a housing, and a side opposite to a surface on which the power module is mounted. The inner surface of the bracket, which faces the one end of the rotor having a fan attached to the end surface of the rotor, has a laminated structure of the bracket, the heat sink, the insulating substrate, and the semiconductor element.
[0011]
In addition, a fin having a heat dissipation function is provided on the inner surface of the bracket to which the power module is attached.
[0012]
The other is a rotating electrical machine for vehicles,
A fan is attached to an end of the rotor, a window is formed in a bracket that holds the rotor and forms a housing of the rotating electric machine, and a power semiconductor device for power having a finned heat sink (for example, a power semiconductor device). A power module having a semiconductor element, an insulating substrate, and a heat sink, and a rectifying diode).
The power semiconductor element is arranged such that the fins of the heat sink are located in a passage of the cooling air flowing through the window by the rotation of the fan.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0014]
FIG. 1 is a longitudinal sectional view of a rotating electric machine according to one embodiment of the present invention, FIG. 2 is a partially enlarged view thereof, and FIG. 3 is a schematic diagram of a laminated structure of a power module used in the above embodiment.
[0015]
As an example, the rotating electric machine in the present embodiment is a vehicle alternator.
[0016]
In FIG. 1, the side of the pulley 2 attached to one end of the rotor shaft 1 is defined as a front side, and the opposite side is defined as a rear side.
[0017]
A rotor 3 on which a field coil 4 is mounted is fixed to the rotor shaft 1, and a stator core 5 is arranged around the rotor 3 via a minute gap. A stator coil 6 is mounted on the stator core 5. Both ends of the rotor shaft 1 are held by a pair of brackets (front bracket, rear bracket) 9, 10 via bearings 7, 8. Further, the front bracket 9 and the rear bracket 10 sandwich the stator core 5.
[0018]
Fans 11 are fixed to both ends of the rotor 3, and when the rotor 3 rotates, cooling air flows into the alternator via an external air intake (not shown) provided on a bracket. The cooling air deprives the heat generated from the field coil 4 and the stator core 5 of the alternator to increase the power generation efficiency.
[0019]
A slip ring 12 for supplying current to the field coil 4 is arranged around one end 1a of the rotor shaft protruding from one bracket (rear bracket) 10. On the outer surface of the rear bracket 10, the slip ring 12, an output terminal 13 for outputting power induced in the stator core 6, a power module 14 for controlling output power, and a rectifying diode (not shown) are attached. Have been. These accessories are covered by a rear cover 15. Reference numeral 16 denotes a magnet for detecting rotation of the rotor.
[0020]
As shown in FIG. 3, the power module 14 includes a power semiconductor device 20, for example, a MOS (complementary metal oxide semiconductor) and an IGBT (insulated gate transistor). And a laminate of a semiconductor element 20, a solder layer 21, an insulating substrate 22, a solder layer 21, and a heat sink 23.
[0021]
The power module 14 is mounted on the outer surface of the rear bracket 10 by screws or the like. Grease 24 is interposed between the power module mounting surface, that is, between the heat sink 23 and the rear bracket 10.
[0022]
The rear bracket inner surface opposite to the power module mounting surface faces one end surface of the rotor 3 to which the fan 11 is mounted. The rear bracket 10 to which the power module 14 is attached, the heat sink 23, the insulating substrate 22, and the semiconductor element 20 form a laminated structure. The heat sink 23 is formed of, for example, aluminum or the like having good heat conductivity. Fins 17 having a heat radiation function are provided on the inner surface of the rear bracket 10 to which the power module 14 is attached.
[0023]
The fins 17 are formed so as to be radial about the rotor shaft 1 as shown in FIG.
[0024]
In the present embodiment, a semiconductor element for power adjustment is exemplified as the power module 14, but this power module may be a rectifier diode used in an AC rotating machine such as an alternator.
[0025]
The power module 14 is housed in a case 26 formed on the surface of the heat sink 23 and is covered by a cover 27.
[0026]
The power semiconductor element 20 of the power module 14 is connected to a bus bar 29 via a wire bonding 28.
[0027]
According to the present embodiment, it is possible to radiate the heat generated by the power module 14 that comes into surface contact with the rear bracket 10 via the heat sink 23 by using the rear bracket 10 as a heat sink. In particular, since the power semiconductor element 20 is mounted directly or via a heat transfer member with the heat generation surface on the mounting side facing the bracket 10, the power semiconductor element 20 has a structure in which the heat of the heat source can easily escape to the bracket 10. That is, the rear bracket 10 has a large heat dissipation capacity, and its inner surface is exposed to the inside of the alternator (between the end face of the rotor with a fan and the inner surface of the rear bracket) which serves as a passage of the cooling air through the fins 17. The heat radiation effect can be enhanced. Therefore, the cooling of the power module 14 can be improved. In particular, even when the power module 14 is covered by the housing 26 and the cover 27 on the outer surface of the bracket 10, an excellent heat radiation effect can be exhibited.
[0028]
FIG. 5 is a partially enlarged view showing another embodiment of the present invention. In the drawing, the same reference numerals as those used in the embodiment (first embodiment) indicate the same or common elements as those in the embodiment.
[0029]
In the present embodiment (second embodiment), the power module 14 similar to the above is mounted on the outer surface of the rear bracket 10 via the heat sink 23, and the fan 11 is mounted on the inner surface of the bracket opposite to the power module mounting surface. The rotor 3 faces one end face of the rotor 3.
[0030]
Fins 23a are formed on the back surface of the heat sink 23 of the power module 14. A window 30a is formed in the power module mounting portion of the rear bracket 10. The window 3a is provided on the end face of the rear bracket 10 so as to open in the axial direction of the rotating electric machine. In the present embodiment, the window 3 a is provided around the rear bearing 8. On the peripheral surface of the rear bracket 10, a window 30b is provided so as to open in the radial direction of the rotating electric machine. A window 15a is provided on the peripheral surface of the rear cover 15 covering the rear bracket end surface so as to open in the radial direction of the rotating electric machine. Therefore, the outside air is introduced from the window 15a of the rear cover 15 by the rotation of the fan 11, and as shown by the arrow A, this outside air becomes the cooling air, passes through the fins 23a, passes through the window 30a, and enters the inside of the bracket (the inside of the rotating electric machine). Will be introduced. Thereafter, the cooling air is discharged outside through the window 30b.
[0031]
In this embodiment, heat transmitted from the power module (including the rectifier diode) 14 to the heat sink 23 can be radiated to the cooling air passage in the alternator via the fins 23a. As a result, the heat radiation effect of the power module can be enhanced.
[0032]
In the above-described embodiment, the alternator for a vehicle is exemplified, but the invention is also applicable to a motor for a vehicle. In addition, when the power module is mounted on the bracket 10 without the heat sink 23, or when the ground side of the power semiconductor element is a surface to be mounted on the bracket, the power module can be mounted on the bracket 10 directly. Performance can be improved.
[0033]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a vehicular rotating electrical machine in which the heat dissipation of the power semiconductor element is improved compared to the related art.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view according to a first embodiment of the present invention.
FIG. 2 is a partially enlarged sectional view of the embodiment.
FIG. 3 is a schematic diagram of a power module used in the present embodiment.
FIG. 4 is an inside view of a rear bracket used in the embodiment.
FIG. 5 is a partially enlarged view showing another embodiment of the present invention.
[Explanation of symbols]
3 Rotor, 10 Bracket (rear bracket), 11 Fan, 14 Power module, 15 Rear cover, 17 Fin, 20 Power semiconductor element, 23 Heat sink, 23a Fin.

Claims (8)

In rotating electric machines for vehicles,
A fan is attached to an end of the rotor, and a bracket that holds the rotor and forms a housing of the rotating electric machine has a power semiconductor element for electric power, and a heating surface on a mounting side of the power semiconductor element on the bracket. A rotating electric machine for a vehicle, wherein the rotating electric machine is mounted directly or via a heat transfer member. In rotating electric machines for vehicles,
A power module having a power semiconductor element, an insulating substrate, and a heat sink is mounted on an outer surface of at least one of a pair of brackets holding the rotor, and an inner surface of the bracket opposite to a surface on which the power module is mounted. Is opposed to one end face of a rotor having a fan mounted on an end face of the rotor, and the bracket on which the power module is mounted and the heat sink, the insulating substrate, and the semiconductor element form a laminated structure. Electric rotating machine for vehicles. The rotating electric machine for a vehicle according to claim 1, wherein a fin having a heat radiation function is provided on an inner surface of the bracket. In rotating electric machines for vehicles,
A diode for power rectification is mounted on an outer surface of at least one of a pair of brackets holding the rotor, and a fin is formed on an inner surface of a bracket opposite to a surface on which the diode is mounted. A rotating electrical machine for a vehicle, wherein the rotating electrical machine faces a first end surface of the rotor to which a fan is attached. The vehicular rotating electrical machine according to claim 3 or 4, wherein the fins are formed radially about an axis of the rotor. In rotating electric machines for vehicles,
A fan is attached to an end of the rotor, a window is formed in a bracket that holds the rotor and forms a housing of the rotating electric machine, and a power semiconductor element for electric power having a finned heat sink is provided.
The rotating electric machine for a vehicle, wherein the power semiconductor element is arranged such that the fin of the heat sink is located in a passage of a cooling air flowing through the window by the rotation of the fan. In rotating electric machines for vehicles,
A power module having a power semiconductor element, an insulating substrate, and a heat sink is mounted on an outer surface of at least one of a pair of brackets holding the rotor, and an inner surface of the bracket opposite to a surface on which the power module is mounted. Is opposed to one end face of a rotor having a fan attached to the end face of the rotor,
A fin is formed on the back surface of the heat sink of the power module, and a window is formed on the power module mounting portion of the bracket, and the flow of the cooling air causes the window from the fin to flow from the fin by the rotation of the fan. A rotating electric machine for a vehicle, characterized in that the rotating electric machine is configured to flow therethrough. In rotating electric machines for vehicles,
A diode for power rectification is mounted on the outer surface of at least one of a pair of brackets holding the rotor via a heat sink, and the inner surface of the bracket opposite to the surface on which the diode is mounted is an inner surface of the rotor. Facing one end face of the rotor with the fan attached to the end face,
A fin is formed on the back surface of the heat sink, and a window is formed on the mounting portion of the diode, and a flow of cooling air is configured to flow from the fin through the window by rotation of the fan. A rotating electric machine for a vehicle, comprising:

Images