Circuit breaker having automatic release linkage

A circuit breaker having an automatic release linkage including a movable conduction unit for selectively conducting a first terminal and a second terminal by contacting the second terminal while being electrically connected to the first terminal, and an open/close linkage including a connection linkage for transmitting an impact force from the movable conduction unit to a trip roller as an operational force, the circuit breaker comprises:

• an open lever;
• a first link rotatably fixing the trip roller, rotatably formed about a latch pin and having a size that does not interfere with an open lever during rotation;
• a second link rotatably coupled at the first link so that a lateral cross-sectional surface thereof can contact the open lever;
• and a spring so interposed between the first link and the second link that the first link can be discretely applied with an elastic spring force from the open lever, wherein an operational moment (77m) trying to rotate the first link by an operational force reacts in a direction opposite to that of an elastic spring moment (Ms) trying to rotate the first link, such that, when an absolute value of the operational moment (77m) is greater than an absolute value of the spring moment (Ms), a lateral cross-sectional surface of the second link connected to the open lever slip on the open lever to rotate the second link relative to the first link, thereby releasing a contacted state between the open lever and the second link.