US Patent 10153634 Switch box and overcurrent preventing method

A switch box includes a circuit substrate having a conductor pattern, a switching element that is mounted on the circuit substrate, a bus bar having a current input and output portion formed at one end thereof and a mounting portion formed at the other end thereof, the mounting portion being connected to the conductor pattern of the circuit substrate so as to be electrically conducted to the switching element through the conductor pattern, and a magnetic sensor that is mounted on the circuit substrate to detect a magnetic field generated due to a current flowing into the bus bar. The magnetic sensor is disposed in a gap formed between the circuit substrate and the bus bar.