Patent ID: 8186525

Claim:
An anti-creep mechanism for a coupler comprising a lower lockpin rod, a coupler shank and a rotation shaft, wherein the rotation shaft is disposed in an elongate mounting hole of the lower lockpin rod and a circular mounting hole of the coupler shank so that the lower lockpin rod and the coupler shank are hinged together, wherein after the lower lockpin rod is moved upwardly, an anti-creep bulge of the lower lockpin rod abuts against an anti-creep surface of the coupler shank to prevent the coupler from being abnormally unlocked, further comprising: a boss axially disposed on an upper surface of the rotation shaft; and a groove axially provided in a wall of the mounting hole of the coupler shank above the rotation shaft to receive the boss of the rotation shaft, wherein the rotation shaft is axially movable relative to the lower lockpin rod and the coupler shank and has two operating positions, wherein when the rotation shaft is moved to a first operating position, an inner end portion of the boss is positioned in the elongate mounting hole of the lower lockpin rod, and a top wall of the elongate mounting hole abuts against the boss, and if the lower lockpin rod is rotated in a coupler unlocking direction, the anti-creep bulge of the lower lockpin rod abuts against the anti-creep surface of the coupler shank and the boss abuts against a sidewall of the groove in the coupler shank; and wherein when the rotation shaft is moved to a second operating position, the boss is positioned in the groove of the mounting hole of the coupler shank, and the top wall of the elongate mounting hole abuts against an outer circumferential surface of the rotation shaft.