Abstract: A circuit breaker comprises a puffer volume (9) and at least one overpressure valve (16) for discharging gas from the puffer volume (9), if the pressure therein exceeds a given threshold. The overpressure valve (16) is formed by a piston (17) and a spring (19) as well as by a cavity (18) in the stationary support body (10) of the moveable contact assembly (2). The overpressure valve (16) is of compact and simple design, has low hysteresis and large cross-section.

Abstract: A circuit breaker comprises a puffer volume (9) and at least one overpressure valve (16) for dis-charging gas from the puffer volume (9), if the pressure therein exceeds a given threshold. The overpressure valve (16) is formed by a piston (17) and a spring (19) as well as by a cavity (18) in the stationary support body (10) of the moveable contact assembly (2). The overpressure valve (16) is of compact and simple design, has low hysteresis and large cross-section.

Abstract: The sheet-metal casing comprises at least two sheet-metal parts (1, 2) and has a plastic seal (9) arranged in between. A first sheet-metal part (1) is folded over along the seal (9) to form a fold (10) and comes into contact with the second part (2) in such a way that, in addition to the fold (10), a gap (13) for accommodating the seal (9) forms. The fold (10) ensures good electrical contact between the two parts (1, 2) and thus good screening. At the same time, it defines the width of the gap (13), so that the seal (9) is subjected to defined compression.

Abstract: A metal-enclosed, gas-insulated switchgear assembly having at least one active part (19) is mounted in an enclosure extended along an axis (18). The active part (19) is provided on at least one side with a contact-making assembly (25). The contact-making assembly (25a) is electrically conductively connected to a connecting part (26) which is provided with a shielding electrode (28). The shielding electrode (28) is connected to a supporting element (35) which bounds an intermediate area (40). The supporting element (35) is connected, on the side facing away from the shielding electrode (28), to a fitting (37) which has holes (39) which originate from the intermediate area (40) and are designed to hold fixing screws. The connecting part (26) is designed for advantageously simply assembly. The connecting part (26) dielectrically shields the heads of the fixing screws.