Patent ID: 7312545

Claim:
An electric power steering system comprising: a motor for electric power steering; and a controller generating alternating current for driving said motor; said motor for electric power steering comprising: a stator equipped with a stator coil; and a rotor supported rotatably inside said stator; said stator being equipped with a stator coil wherein the stator core is split, and the stator core is integrally constructed thereafter; said rotor comprising: a rotor core; and a plurality of magnets secured on the surface of said rotor core; wherein said magnets whose stator side is curved and whose polarity reverses alternately in the circumferential direction are magnetized in the axial direction; said motor for electric power steering further comprising: a connection board on the side of the stator for supplying alternating current to the stator coil; said controller incorporating: a power module equipped with a semiconductor switching device; a conductor module; and a control module; inside the case; said control module supplying said power module with the control signal for generating the control signal for controlling said semiconductor switching device and driving the motor for electric power steering; said power module containing a semiconductor switching device, and generating 3-phase alternating current for driving said motor in conformity to said control signal; said conductor module comprising: a bottom formed of resin; a plate-formed conductor provided on said bottom; a relay; and a capacitor; wherein said plate-formed conductor forms a circuit for sending 3-phase alternating current to be supplied to the motor for electric power steering; wherein said conductor module is secured onto one side of the case interior in such a way that the bottom thereof will be located at the upper position; said power module is arranged on the other side of the case interior; and said power module and plate-formed conductor of the conductor module are electrically connected; wherein a chamber is formed between the bottom of the case and the bottom of the conductor module arranged in such a way that the bottom thereof will be located at the upper position; and said relay and capacitor are arranged in the chamber; wherein a hole is provided on the bottom of said conductor module arranged in such a way that the bottom thereof will be located at the upper position; said relay and capacitor terminals protrude from the hole; and said protruding terminals and plate-formed conductor are connected by welding; and wherein the alternating current generated by the power module is supplied to the stator coil through the connection board for the motor for electric power steering.