JPS64814B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rectifying device used in a vehicle alternator or the like.

(Prior Art) The semiconductor rectifier connection structure in a conventionally known rectifier is as shown in FIG.
is a semiconductor rectifier, 1D is a concave copper disk,
A lead 1L and a semiconductor element 1P are connected and fixed inside this disk 1D with solder 1S, and hermetically sealed with silicone rubber 1R.
Cooling fins 3 are bonded and fixed to the outside of D with solder 2, but in order to reduce the weight of the rectifier due to recent social needs such as resource saving and energy saving, the material of the cooling fins 3 has been changed to a light metal such as aluminum. It is being changed to
However, when light metal is used as the cooling fin material, it has a large coefficient of thermal expansion, so if the temperature is applied during actual use, the disk 1 of the semiconductor rectifier
Thermal strain is applied to D through the solder 2 due to the thermal expansion of the cooling fins 3, and since the mechanical strength is small, the influence of mechanical strain on the semiconductor rectifier becomes large, significantly shortening the life of the semiconductor rectifier. There is a problem of lowering the

(Object of the present invention) In view of the above-mentioned problems, the present invention provides a lightweight, low-cost, high-quality rectifier in which the cooling fins are made of a light metal such as aluminum, and in which the semiconductor rectifier is less susceptible to distortion. The purpose is to

(Structure of the present invention) The present invention provides a metal plate with good thermal conductivity and solderability, and a part of the groove on the bottom surface formed by providing an annular groove in the embossed recess of a cooling fin made of a light metal. The connection structure is such that a semiconductor rectifier is soldered to this metal plate-like body by solid-phase bonding so as to cover the metal plate.

(Example) Hereinafter, an example of the present invention shown in the drawings will be described. FIG. 2 is a vertical cross-sectional view showing the configuration of an embodiment of the rectifier according to the present invention, in which 1 is a semiconductor rectifier, and a semiconductor element 1P and a lead 1L are connected and fixed in this order to a concave copper disk 1D with solder 1S. The lead 1L is connected to an AC input terminal (not shown) on the input side, and the disk 1D is connected to a cooling fin 3 made of light metal such as aluminum as a DC electrode. A solderable metal plate-like body, for example, a copper plate 4, is integrated in a solid state at the bottom of the embossed recess so as to cover a part of the annular groove 3b formed at the bottom of the recess of the embossed part 3a. are joined and fixed.

(Effects of the Present Invention) As described above, the rectifying device according to the present invention has a flow rectifying device that is arranged so as to cover a part of the annular groove formed at the bottom of the concave portion of the embossed portion of the light metal cooling fin. The semiconductor rectifier is joined and fixed with solder to a metal plate with good thermal conductivity and solderability, which is integrated by solid-phase bonding, so it has the following advantages compared to conventional equipment. has.

(1) When the temperature is applied during actual use, the grooves make the disk of the semiconductor rectifier
Since the structure is connected only to the bottom of the embossed part of the cooling fin, compared to the conventional structure in which the entire disk is connected so as to be covered by the concave part of the embossed part of the cooling fin, it is easier to pull out from the side of the disk. Since there is no tensile force, the effect of distortion on the disk from the cooling fins is reduced, and there is an effect that it is possible to provide a rectifying device that is less susceptible to the effects of distortion due to heat.

(2) If the light metal cooling fin is subjected to external strain during actual use, forming a groove at the bottom of the concave part of the embossed part of the cooling fin reduces the plate thickness of the groove, which reduces the rigidity and prevents the distortion. This has the effect that the distortion effect on the disks of the semiconductor rectifier is considerably alleviated by absorbing it in the groove, and it is possible to provide a rectifier device that is less susceptible to mechanical distortion effects.

(3) When the metal plate is integrated with the cooling fin by solid state bonding, it is integrated so as to cover part of the annular groove, so any burrs that are generated are suppressed by the metal plate and trapped inside the groove. This has the effect of allowing the metal plate and semiconductor rectifier to be joined and fixed using highly reliable soldering.

[Brief explanation of drawings]

Figure 1 is a longitudinal cross-sectional view of the main parts of a conventional rectifier;
The figure is a longitudinal cross-sectional view of a main part showing the configuration of an embodiment of a rectifying device according to the present invention. 1...Semiconductor rectifier, 1D...Disk, 1P
...Semiconductor element, 1L...Lead, 1S, 2...
Solder, 3... Cooling fin, 3a... Embossed part,
3b... Annular groove, 4... Metal plate-like body.

Claims (1)

[Claims] 1. Good thermal conductivity and solderability integrated with the bottom of the concave part of the embossed part by solid phase bonding so as to cover a part of the annular groove formed at the bottom of the concave part of the embossed part of the light metal cooling fin. A semiconductor rectifier is formed by fixing semiconductor elements and leads inside a concave disk to a metal plate, and hermetically sealing the semiconductor rectifier.
A rectifying device characterized by being fixed.