Abstract: The invention describes a bimetallic thermal switch comprising an electrically insulating carrier (2), a contact spring (4) made from a bimetallic material, which is carried by the electrically insulating carrier (2) and has two ends, one being fixed in position, and which is so formed, at least over a certain portion (4a), that it will abruptly change its curvature when its switching temperature is exceeded; two electric supply lines (8, 9) held on the insulating carrier (2) and leading to two contact pieces (6, 7) disposed separately one from the other and from the contact spring (4); and a contact bridge (5) mounted on the contact spring (4) opposite the two contact pieces (6, 7).

Abstract: An flat casing (10) exhibiting a convex curvature to the outside on all sides, is slid onto the projection (1a) of a base (1). The casing (10) protects a contact device anchored in the base (1). The base (1) protrudes with the peripheral brackets (1b), formed on two sides of the base (1), beyond the projection (1a) into the casing (10) and supports the casing (10) from the insides A U-shaped carrier plate (4) is anchored with its arms (4a) in the brackets (1b). The carrier plate (4) is furnished with longitudinal edges (6), which are bent off at right angles outside of the anchoring, and the longitudinal edges (6) rest force-matchingly at the interior wall of the casing (10).

Abstract: An easily and preferably fully automatically manufacturable thermal switch having a minimum number of parts is disclosed. The thermal switch has two connecting parts fixed to a support part. One connecting part carries a fixed contact and the other connecting part is connected through a high resistance to a movable contact switchable by a bimetallic element. The support part is a ceramic part forming the high resistance from a PTC material and the connecting parts are almost completely frictionally engage support part.

Abstract: The material for electric contacts having arc-quenching properties comprises an irreversibly cured polymeric molding compound, which contains 5 to 20 volume percent of a metal powder and optionally contains up to 40 volume percent of an additional filler consisting of an electrically non-conducting inorganic powder. The selected thermosettable molding compound can be cured without forming a liquid phase.

Abstract: The power circuit breaker particularly for use in medium-voltage switchgear comprises contacting parts consisting of a contact pin, which is displaceable in the direction of its longitudinal axis, and a contact socket, which is coaxial to said pin and comprises a forward portion adapted to contact the pin. That forward portion of the socket is formed with axial slots dividing that forward portion into axial segments. Each of said segments comprises at its tip a covex portion, which protrudes radially inwardly and resiliently bears on the pin when the breaker is closed. In such breaker the pin has a forward portion, which comprises a tip and which has a length that is smaller than the largest depth to which the pin can be inserted into the socket. That forward portion consists of a composite material, which contains a metal having a high electrical conductivity and a material which releases quenching gases under the action of an electric arc.