A high-stability miniature circuit breaker has a pivotal shaft having a first section, a second section and a shoulder. The diameter of the second section is larger than the first section. The shoulder diameter is larger than the second section. A pivoting lever on the first section limits the axial position of a protruding mesa relative to the shaft by contact fit between the mesa and a thrust surface on the second section. A pivoting latch is on the second section. A first end face fits to a support surface on the shoulder. A second end face fits to the protruding mesa at the other end. The latch controls a drive rod and the lever. A connecting rod separates from the latch when latch hasps are separated and the latch separates from the drive rod which slides along a groove of the lever.

An actuator (10) for actuating a vacuum switch tube (11) comprising a fixed contact (12) and a movable contact (13), comprises a bearing plate (14) that can be fastened to the fixed contact (12); a main spring (15) having a first end (151) with which it can engage the movable contact, and a second end (152); a return spring (16) having a first end (161) with which it engages at the bearing plate, and a second end (162); an actuating lever (17) having a first engagement area (171) at which the main spring (15) engages with its second end (152), and having a second engagement area (172) at which the return spring (16) engages with its second end (162);
wherein the actuating lever (17) is swivelably mounted on the bearing plate (14) such that the actuating lever (17) can assume a first end position in which the main spring (15) is at least partially relaxed and the return spring (16) is tensioned and in which, in particular, the movable contact (13) is disconnected from the fixed contact (14), and a second end position in which the return spring (16) is at least partially relaxed and the main spring (15) is tensioned and in which, in particular, the movable contact (13) is pressed against the fixed contact (14).

A high current switching device includes an electrical switch assembly and an input shaft operatively connected to the electrical switch assembly. An actuator assembly is attached to the input shaft and is configured to move the input shaft to operate the electrical switch assembly. The actuator assembly includes a mechanical advantage device operatively attached to the input shaft. An actuator is coupled to the mechanical advantage device such that movement of the actuator causes movement of the input shaft to operate the electrical switch assembly. The mechanical advantage device is configured to decrease an amount of force required to move the input shaft by the actuator.

A high current switching device includes an electrical switch assembly and an input shaft operatively connected to the electrical switch assembly. An actuator assembly is attached to the input shaft and is configured to move the input shaft to operate the electrical switch assembly. The actuator assembly includes a mechanical advantage device operatively attached to the input shaft. An actuator is coupled to the mechanical advantage device such that movement of the actuator causes movement of the input shaft to operate the electrical switch assembly. The mechanical advantage device is configured to decrease an amount of force required to move the input shaft by the actuator.