Abstract: A power circuit breaker (1) is provided with an arrangement that controls its switching-on depending on operating parameters (A . . . E, M1, M2, S). These parameters may be, for example, the position of switching contacts, the state of excitation of an undervoltage release and the switching position of another power circuit breaker. The arrangement has a coupling shaft (32) that may be rotated by a tripping half-wave by means of a steering lever (34) and by certain parameters by means of a sensor lever (36). A coupling member (20) that may be swivelled by the coupling shaft (32) allows a ratchet device (5, 6) of the energy store (7) of the power circuit breaker (1) to be released only when all conditions required for switching-on are met.

Abstract: A multi-pole low-voltage power switch designed with several switching chambers per pole and a common switching shaft which acts for the pole units is formed by the switching chambers. The switching shaft is made up of shaft sections which correspond to the pole units. While the central shaft section has central pins and levers, the peripheral shaft sections are fitted with levers and have central apertures in which the pins engage. Bolts which pass through the levers are used to couple the shaft sections together. The pole units rest on a support which is dimensioned to accommodate the maximum width of the pole units and to allow for possible variations in their dimensions. Side walls of the correct dimensions for a pull-out rack enclosed the supporting framework of the power switch on each side.

Abstract: A vacuum switch has a vacuum interrupter which can be actuated by a drive device using a lever arrangement. A two-armed drive lever is mounted in a pivotable fashion on the displaceable connection bolt of the vacuum interrupter and interacts with a stop face against which the drive lever can be rested by a contact spring. In order to compensate contact-breaking forces, a loop-shaped, flexible strip conductor is used which is arranged between the two legs of the drive lever in such a way that one leg of the strip conductor rests on a central part of the drive lever while the other leg is supported in a fixed manner. The current-loop and lever assembly is suitable for the construction of compact power switches.

Abstract: Mechanical signals which are made available in the form of limited travel distances can be fed, for obtaining at least one output variable, to an arrangement in which plungers assigned to the input variable are arranged in space parallel to each other, wherein a slide movably guided likewise parallel to the plungers is provided for the transmsision of force between the plungers. For obtaining a logical AND interconnection, at least one plunger for a first input signal can be guided at the slide and at least one plunger can be arranged approximately opposite the former for the output signal and the slide an have a working surface for at least one corresponding plunger for action by a further input signal. Arrangements of this kind can be used in conjunction with wire tripping devices in electrical switching installations for interlocking purposes.

Abstract: The parts of a support structure which can be assembled together have rimmed holes and openings going through them centrally. A conical nut is screwed onto a countersunk screw which goes through the openings, and the nut has a conical surface which has a cone angle that is the same as the inner conical surface of the opening of a corresponding rimmed hole. The described screw connection is particularly well suited for support structures which are heavily stressed by shocks, vibrations or other disturbances and is found to be durably resistant under these conditions without additional means for securing the screw and nut.

Abstract: An energy accumulator for a circuit breaker comprises a cross piece which can be inserted between side walls of the support mechanism of the circuit breaker, which has a substantially U-shaped cross section and against the center part of which coil compression springs are braced. With their opposite ends, the springs rest against a movable abutment which likewise has a U-shaped cross section. A push rod which goes through one of the springs in its longitudinal direction is guided in the cross piece and has a transverse hole for inserting a securing pin in the partially cocked state of the springs. Between the legs of the cross piece there are inserts which have an extension pointing in the direction of the movable abutment. Thereby, a space for the engagement of a leg of the movable abutment is formed if the springs are tensioned more heavily.

Abstract: For cocking an energy accumulator, an actuating device comprises a ratchet wheel with teeth as well as a reciprocating transport ratchet. For maintaining the cocked position of the energy accumulator, a cam wheel and blocking lever which can be braced against a blocking member via a ratchet lever are provided. Due to a wedge-like cooperation between a working surface of the cam wheel and a projection of the blocking lever, the blocking lever is transferred from its rest position into a blocked position if the deadcenter position of the cam wheel is exceeded. In the process, the transport ratchet is lifted from the teeth of the ratchet wheel by means of a striking surface of the blocking lever.

Abstract: A pull-out frame for a switching device with a threaded spindle and a tripping device which can be actuated by a tool provided for actuating the threaded spindle. In the switching device, a coupling member is arranged which transmits the motion of the tripping device of the pull-out frame to a tripping device of the switching meachanism of the switching device. A latching device controlled by the positioning drive makes provision that the tripping device is released only in the course of the travel motion of the switching device for resetting.

Abstract: A drive mechanism for a circuit breaker has a spring which is to be tensioned by means of a shaft. On said spring sits a clamp-roll freewheel as a directional lock, whose outer part is connected via a flexible strip traction member to one or more eccentric members. The clamp rollers can be pressed out of their operating position by means of cage disks, which occurs upon reaching the end position of the spring-tensioning shaft by means of a release lever in connection with toggle levers.

Abstract: A contact assembly for electrical circuit breakers has a contact lever and a lever support with the contact lever mounted thereon in an articulate fashion. The support lever is flexibly positioned around a fixed pivot bearing by a drive linkage device for on- and off-switching cycles. A pressure lever is used to introduce a current-dependent force onto the contact levers in order to increase the contact force. The pressure lever is similarly flexibly mounted onto the lever support. The contact lever and the pressure lever operate jointly via their working surfaces which permit a conveyance of force in terms of an increase of the contact force. When switching on the contact assembly, the pressure lever is decoupled from the contact lever so that the tendency to bounce is reduced.