The invention discloses an implementing mechanism of a vehicle electronic
parking brake system. The invention comprises a transmission device and a
brake clipping caliper
assembly. After the output of the
direct current motor in the transmission device is performed with
speed reduction and torque increase via a synchronization belt transmission device and a
involute few tooth difference planetary transmission device, the rotation motion is transferred into a straight line motion through a sliding
helical transmission mechanism, and a braking disc is braked through the method that a
piston and a braking block
assembly are pushed by a screw sleeve. The circumferential freedom degree of the
piston is limited by the braking block
assembly, and the circumferential and the racial freedom degrees of the screw sleeve are respectively limited by a
piston non-round hole and a blocking ring. The screw sleeve and a screw rod adopt
self locking thread matching, to guarantee the parking braking to be secure and reliable. Compared with the implementing mechanism of the traditional vehicle rear wheel parking
braking system, the invention has the advantages that the driving cab space is saved, the labor intensity of the driver is reduced, the parting braking is more secure and reliable, and the invention is convenient for adopting
intelligent control and integrating other functions.