Electric power steering apparatus

摘要

An electric power steering apparatus can improve heat dissipation of a power board. A heat sink is mounted on the power board in surface contact therewith, on which power board there is mounted a bridge circuit including a plurality of semiconductor switching elements for switching an electric current supplied to an electric motor in accordance with torque assisting a steering wheel. The heat sink has a plurality of protrusions formed on a surface thereof at a side opposite to the power board.