Circuit breaker provided with means that reduce the switching arc between permanent contacts

A circuit breaker or switch comprising a first permanent contact (1) and a first arcing contact (2) and also a second permanent contact (4) and a second arcing contact (5), the second contacts (4, 5) being movable relative to the first contacts (1, 2) in such a manner that, during switching or circuit-breaking movements, the permanent contacts (1, 4) separate from each other before the arcing contacts (2, 5), the second contacts being linear and extending in the direction of the movements, and the second permanent contact (4) being placed between the first permanent contact (1) and the arcing contacts (2, 5), sliding contacts (9, 10), which are stationary relative to the first contacts, being in electrical connection with the second contacts (4, 5), the circuit breaker or switch being characterized in that the second permanent contact (4) includes a nose end (8) directed towards the first contacts (1, 2) and separated from a main portion (11) of the second permanent contact (4) by a spacer (12) that electrically insulates said nose end and said main portion from each other, the sliding contacts are subdivided into a first portion (9) connected to the main portion (11) of the second permanent contact and a second portion (10) connected to the nose end (8) of the second permanent contact, the first permanent contact (1) is suitable for being electrically connected with only the nose end (8) of the second permanent contact (4), and the nose end includes a narrowing step (14) at a front portion, so that, during said switching or circuit-breaking movements, the second portion (10) of the sliding contacts is separated from the nose end (8) before the first permanent contact (1).