| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a disc brake capable of securing favorable operation efficiency. <P>SOLUTION: A piston holding mechanism 34 provided at the disc brake 1a includes a planetary gear reduction mechanism 34 which raises the rotation of a motor 38, and a screw mechanism 52 and a ball and ramp mechanism 28 for converting the rotation of the planetary gear reduction mechanism 34 into a linear motion so that a piston 12 is advanced in parallel. The planetary gear reduction mechanism 34 transmits such a rotational output as an input from the motor 38 and is enhanced to the screw mechanism 52 or the ball and ramp mechanism 28, and transmits a reaction force of the rotation output to the screw mechanism 52 or the ball and ramp mechanism 28. The screw mechanism 52 keeps a stopped state when the supply of a rotational force from the motor 38 is stopped. Thus, favorable operation efficiency is secured. <P>COPYRIGHT: (C)2012,JPO&INPIT |
