To provide a circuit breaker combining a break part and control part, capable of certainly breaking a circuit in a short time to protect an electrical component when an abnormal signal of a vehicle is inputted.
In this circuit breaker, a current sensor 73 detects a current flowing through a first bus bar 11, and a CPU 74 outputs a drive control signal to a drive circuit 77 when the detection current of the current sensor 73 becomes above a threshold current. The drive circuit 77 operates an ignition part 29 through a second board 65 and a terminal 50 to ignite the ignition part 29, heat generated by a heating agent 27 melts a second projecting part 41, and a compression spring 34 expands to spring up a thermite case 26, so that electrical connection of the thermite case 26 with first and second bus bars 11, 19 is broken. An outer vessel 61 housing the current sensor 73, the CPU 74 and the drive circuit 77 is integrally installed to a cap 14a and a resin case 14b housing the thermite case 26, the ignition part 29, the compression spring 34 and the second projecting part 41. Thereby, no operation failure of the ignition part 29 caused by disconnection of wire or the like occurs.
GOHARA TAKASHI
TAMAI YASUHIRO
TAKAHASHI HIDEO
MORIMOTO MITSUAKI
IKUTA YOSHINORI
