| 摘要 |
<p>An electric parking brake system capable of achieving efficient operation while reducing generation of noise. The electric parking brake system comprises first and second parking cables (41,42) to be connected to brakes that are used to stop rotation of wheels of a vehicle, a motor (110) to generate a drive force required to selectively operate the parking cables (41,42), a drive gear (121) adapted to rotate in accordance with operation of the motor (110), a planetary gear unit (130), and a screw-nut unit (140). The planetary gear unit (130) includes a sun gear (131) connected to the drive gear (121) in a power transmittable manner, a plurality of planetary gears (132) gearedly connected with the sun gear (131) and adapted to revolve along a periphery of the sun gear (131), an internal gear (134) formed along a revolving path of the planetary gears (132) and adapted to be gearedly connected with the planetary gears (132), and an output carrier (135) connected to the planetary gears (132) in a power transmittable manner and adapted to rotate about the same rotating center as that of the sun gear (131). The screw-nut unit (140) includes a screw member (141) and a nut member (145) screwed to the screw member (141) to perform a relative linear movement. The screw-nut unit (140) is coupled to the output carrier (135) in a power transmittable manner. The parking cables (41,42) are connected to opposite ends of the screw-nut unit (140), respectively, and are adapted to be operated by the relative linear movement of the screw member (141) and nut member (145) during rotation of the output carrier (135).</p> |
