Clearance adjusting decelerator and electric power steering apparatus having the same

An electric power steering apparatus, comprising:

• a worm wheel connected to a steering shaft;
• a worm engaged with the worm wheel;
• a motor for providing a rotational force to the worm;
• and
• a gear housing enclosing the worm wheel, the worm and the motor,
• wherein the gear housing comprises:
• a rotary housing comprising a worm/motor housing including the worm therein and a worm wheel housing having both sides open, the rotary housing being rotatable about a worm wheel housing pivot center axis;
• a first worm wheel housing cap comprising a first cap tooth formed on one side surface and a first body integrally formed with the first cap tooth, the first body comprising a first inserting hole, formed on a center portion, to have the steering shaft pass in it and at least one first assembly hole formed on a rim thereof, wherein a worm wheel center axis passing through a center of the first inserting hole is spaced apart from the worm wheel housing pivot center axis;
• a second worm wheel housing cap comprising a second cap tooth formed on one side surface and a second body integrally formed with the second cap tooth, the second body comprising a second inserting hole, formed on a center portion, to have the steering shaft pass in it and at least one second assembly hole formed on a rim thereof, wherein a worm wheel center axis passing through a center of the second inserting hole is spaced apart from the worm wheel housing pivot center axis;
• and
• at least one fastening member passing through at least one first assembly hole formed on the first worm wheel housing cap and at least one second assembly hole formed on the second worm wheel housing cap.