US Patent 7679235 Engine starter with protective function against over current

In a starter for starting an engine having a motor to which starting current is supplied from a battery, the motor has a field coil for forming a magnetic field with the supply of current, and the starter has wiring for supplying current from the battery to the field coil. The wiring has a cross section perpendicular to the longitudinal direction, which is smaller than a cross section perpendicular to the longitudinal direction of the winding of the field coil, so that a cross section reduction portion is integrated into the wiring. The cross section reduction portion functions as a fuse for shutting down an internal circuit of the motor at an earlier occasion when an overcurrent passes through the internal circuit.