Low-voltage circuit breaker

A low-voltage circuit breaker belongs to the technical field of low-voltage electric appliances. Which comprises a shell, an arc extinguish chamber, an exhaust channel formed in the shell and used for communicating the arc extinguish chamber with the outside of the circuit breaker, and a deionization device arranged in the shell and located in the exhaust channel, and is characterized in that one side, close to the arc extinguish chamber, of the deionization shell is assembled with the shell in a matched manner; an extension part is formed on one side far away from the arc extinguish chamber; and a gap L is formed between the lower part of the extension part and the bottom of the shell. The circuit breaker has the advantages that the cooperation of the exhaust port of the circuit breaker and the deionization device is optimally designed, the insulation distance between the deionization device and the ground is increased, and the ground breakdown of each phase of the circuit breaker is effectively prevented. 一