Abstract: A pole of a low-voltage limiting electrical power circuit breaker comprises a stationary contact defining a contact area, at least one movable contact finger and an arc extinguishing chamber. The finger is pivotally mounted on a movable support, itself linked to an opening mechanism. A spring biases the finger to a contact position. The lateral branches of a U-shaped magnetic circuit bound the contacts on each side, with interposed insulating side walls which form a passage between the contact area and the arc extinguishing chamber. This passage forms a constriction at the inlet of the chamber. The pole comprises in addition a receiving surface of an electric arc root, situated between the contact area and the constriction and electrically connected to the contact area and which is extended towards the inside of the chamber by a narrower part.

Abstract: An electrical circuit breaker pole comprises a stationary contact means, a movable contact means, and an arc extinguishing chamber comprising two side flanges, separators, a front opening situated near to the contact zone of the stationary contact means, a lower arcing horn, an upper arcing horn and a pair of lateral dielectric shields laterally limiting the front opening of the chamber. Each lateral dielectric shield is arranged in such a way as to be interposed laterally between the separators and the movable contact means in the open position. The pair of lateral dielectric shields is arranged in such a way that the width of the opening of the chamber is appreciably smaller near to the upper arcing horn than pear to the lower arcing horn.

Abstract: A pole of a low-voltage limiting electrical power circuit breaker comprises a stationary contact defining a contact area, at least one movable contact finger and an arc extinguishing chamber. The finger is pivotally mounted on a movable support, itself linked to an opening mechanism. A spring biases the finger to a contact position. The lateral branches of a U-shaped magnetic circuit bound the contacts on each side, with interposed insulating side walls which form a passage between the contact area and the arc extinguishing chamber. This passage forms a constriction at the inlet of the chamber. The pole comprises in addition a receiving surface of an electric arc root, situated between the contact area and the constriction and electrically connected to the contact area and which is extended towards the inside of the chamber by a narrower part.

Abstract: An electrical circuit breaker pole comprises a stationary contact means, a movable contact means, and an arc extinguishing chamber comprising two side flanges, separators, a front opening situated near to the contact zone of the stationary contact means, a lower arcing horn, an upper arcing horn and a pair of lateral dielectric shields laterally limiting the front opening of the chamber. Each lateral dielectric shield is arranged in such a way as to be interposed laterally between the separators and the movable contact means in the open position. The pair of lateral dielectric shields is arranged in such a way that the width of the opening of the chamber is appreciably smaller near to the upper arcing horn than near to the lower arcing horn.