Miniature circuit breaker

The miniature circuit breaker comprises a shell, a movable contact, a static contact and an operating mechanism, the movable contact, the static contact and the operating mechanism are located in the shell, and the operating mechanism is used for controlling connection and disconnection of the movable contact and the static contact; the operating mechanism comprises a supporting piece, a transmission assembly, a lock catch and a lock catch linkage piece, the lock catch is rotationally arranged on one surface of the supporting piece, and the lock catch linkage piece is arranged on the other surface of the supporting piece and fixes the lock catch on the supporting piece; the transmission assembly and the lock catch are engaged to ensure that the circuit breaker is stably in a fixed linkage state. The operating mechanism further comprises a blocking piece, the blocking piece synchronously moves along with the operating mechanism, and the blocking piece is at least arranged in the direction, close to the movable