Abstract: The present invention relates to a stationary contact for a low-voltage circuit breaker constituted by a contact holder element having a shaped slot and by a contact element fastened to the contact holder nearby the slot in order to generally improve the features of a low-voltage circuit breaker.

Abstract: The present invention relates to an electrical arc interruption chamber, in particular for fluid-quenched circuit breakers, in which, inside a tightly sealed insulating encasing, containing an arc-quenching gas, provided are current-bearing connections, respectively supporting a movable main contact and a stationary main contact, each one of the main contacts being provided with its respective arc contact, and wherein the movable arc contact of the tulip type is positioned inside a wall element of insulating material, having, e.g., the shape of an upside-down bell, the movable contact and the bell-shaped element being housed inside the body of the movable main contact, in order to define a first chamber for the passage of the arc-quenching gas between the said body and the said insulating element, defined being furthermore a second chamber for the passage of the arc-quenching gas, which is movable between the movable arc contact and the bell-shaped element.

Abstract: An automatic locking device for linkages subjected to undesirable mechanical stresses comprises a transducer with transmits an electrical signal as a function of the mechanical stress received, and feeds it to a coil which generates an electromagnetic field causing locking of the linkage.

Abstract: In an arc contact system for electrical circuit breakers, in particular of the type using an arc extinguishing fluid, comprising a stationary contact and a movable contact, one of the two arc contacts is formed by a tubular cylindrical body bearing a hollow sleeve of arc resistant material at its end destined to cooperate with the other arc contact; and the other arc contact is formed by a substantial cylindrical rod provided with at least one central longitudinal cut, suitable to render elastically yielding in the radial direction said rod, destined to be inserted inside the tubular cylindrical body of said first arc contact.

Abstract: In an electric circuit breaker of the type using an arc quenching fluid with pressure self-generating by the breakdown of the fluid due to the same arc, comprising, inside a tightly sealed insulating casing filled with the extinguishing fluid, in particular with such a gas as sulphur hexafluoride, two plate-shaped current bearing connections, of which one supports a stationary main contact and a tubular stationary arc contact, and the other is provided with a guide for a stem supporting a movable main contact and a rod-shaped movable arc contact, a drive mechanism for moving said stem from a closure position to an opening position of the contacts and vice-versa, a first extinguishing fluid collecting and compression chamber surrounding the stationary arc contact and having an outlet opening suitable to be closed by said movable arc contact, at least a further collecting and compressing chamber having an outlet opening, as well as means for closing said outlet opening of said further chamber, the outlet openin

Abstract: A high-voltage electric switch is proposed comprising an arc extinguishing device using self-generation of a quenching fluid pressure. Inside a container there is formed a compression chamber surrounded by fixed main contacts cooperating with mobile main contacts carried by a movable rod. Movable to a limited extent by said rod during its closure travel against elastic means, there are disposed in said chamber a first pair of arcing contacts for forming an auxiliary arc the main purpose of which is to generate a pressure in the quenching fluid contained in the compression chamber, and a second arcing contact which cooperates with the rod in order to form a main interruption arc which is blasted at the appropriate time by the thus compressed fluid, the arcing contacts being in series with each other and in parallel with the main contacts.

Abstract: The present invention relates to an electrical circuit breaker with arc extinguishing compressed fluid, in which the compression of the extinguishing fluid is caused in a mixed way, by the pneumatic action of a compressing piston solid with the movable contacts of the circuit breaker and by pressure self-generation, following the action of the electrical arc, which decomposes and heats the fluid.

Abstract: A plug-in electric switch which includes a mobile unit and a fixed unit, the fixed unit having a recess and a spring biased sliding plate, the mobile unit including a contact arm and main contacts, secondary contacts carried by both the mobile and the fixed units, a rod slidably mounted relative to and carried by the mobile unit, the rod having an end with an inclined face adapted to contact an inclined face of a slidably mounted latch, spring biasing the latch in a direction to maintain the faces in sliding contact, and another spring normally biasing the rod in a direction toward the contact or support arm such that when the main contacts are closed the mobile and fixed units are prevented from being disengaged or re-engaged and at a partially engaged position the main contacts cannot be closed.

Abstract: An electric switch including fixed and movable contacts, the movable contact being carried by a pivoted arm movable between a first position at which the fixed and movable contacts are in closed contacting relationship and a second position at which the fixed and movable contacts are in open noncontacting relationship, a control lever, a pivot mounting the control lever for movement between first and second positions thereof corresponding to the closed and opened positions respectively of the contacts, a toggle linkage including a plurality of links operatively interconnected between the arm and the control lever, a spring connected between the toggle linkage and the control lever for moving the arm from the first position thereof to the second position thereof and vice versa upon movement of the control lever respectively from the first to the second positions thereof and vice versa absent the contacts being welded together in the closed position thereof, the links being disposed generally in-line in the clo

Abstract: An electric switch assembly is split into two mating units one of which contains the mechanical control component parts, the accessories and display means, the other unit containing the fixed contacts and the tripping means for the switch. Further seats can be provided to make arc-quenching chambers.

Abstract: An electric switch, more particularly a current-limiter, to be actuated by a control pin which indicates the OFF or the ON condition, and which can be opened also by the agency of thermomagnetic tripping mechanisms and by means of a coil. A crank lever is linked to a swinging assembly which is rockably mounted about the pin and to a rocker carrying the rod to actuate the movable contacts. The lever, to be able to permit that the contacts may be closed, must rest on a step of another lever and this resting relationship can be undone either by acting upon the pin, or by means of the tripping mechanisms and the coil. The opening by means of the tripping mechanisms takes place with a kind of "stroke trip" action, the mechanism being automatically reset during opening. The action of the tripping mechanisms is visually displayed and the reclosure of such a switch can be caused dependent from a local intervention by means of a pushbutton.