Abstract: An electrical passage for an hermetic enclosure including electronic elements comprises a conducting piece (2) traversing an insulating sleeve (3) bearing on the inner surface (1) of the enclosure. A ring (7) surrounds the conducting piece (2) and a portion of the insulating sleeve (3) projecting outside of the enclosure, and a nut (13) inserted onto the conducting piece (2) ensures fastening of the assembly. A full ring seal (10) disposed between the inner surface (11) of the ring (7) and the outer surface (12) of the insulating sleeve (3) is compressed longitudinally by the outer wall (8) of the enclosure and by a shoulder (6) of the conducting piece, thus ensuring the hermeticity of the assembly. The tightening of the nut (13) acts on the insulating sleeve (3) within the enclosure. The invention has application to the electrical connection of power semiconductors utilized within the domain of railway traction.

Abstract: In electrical apparatus of the type having a column of stacked semiconductors and interposed heat sinks mounted between a pair of end plates, a precalibrated clamping element is provided for applying a predetermined clamping force to one end of the column to secure the column between the end plates. A hollow cylindrical body of the clamping element threads into one of the end plates and houses a spring which has been placed in precalibrated compression by a press. The spring is retained in a precalibrated state between a shoulder portion of a piston within the body and a fixed inner surface of the body. A cap is secured to an end of the body and is positioned to abut the shoulder to retain the spring in the precalibrated state.

Abstract: A power semiconductor assembly in which two metallic heat sinks with inner planar surfaces clamp between these surfaces a housing of a power semiconductor therein at a set clamping pressure. The casing has planar surfaces against which the inner planar surfaces of the heat sinks are clamped. Three threaded rod assemblies are assembled in three sets of recesses on the heat sinks controlling the pressure applied to the semiconductor assembly. Each heat sink has three recesses communicating with outer surfaces thereof aligned axially with corresponding similar recesses of the other heat sink. The rod assemblies each have a pair of threaded rods joined coaxially by a molded element made of, for example, porcelain, or a resin epoxy such as "Araldite", or a mica-glass composition. Nuts are threaded on the two rods and a calibrated elastic washer on one rod hold the entire assembly at the desired clamping pressure.

Abstract: A power semiconductor assembly in which two metallic heat sinks with inner planar surfaces clamp between these surfaces a housing of a power semiconductor therein at a set clamping pressure. The casing has planar surfaces against which the inner planar surfaces of the heat sinks are clamped. Three threaded rod assemblies are assembled in three sets of recesses on the heat sinks controlling the pressure applied to the semiconductor assembly. Each heat sink has three recesses communicating with outer surfaces thereof aligned axially with corresponding similar recesses of the other heat sink. The rod assemblies each have a pair of threaded rods joined coaxially by a molded element made of, for example, porcelain, or a resin epoxy such as "Araldite", or a mica-glass composition. Nuts are threaded on the two rods and a calibrated elastic washer on one rod hold the entire assembly at the desired clamping pressure.