Patent ID: 8880312

Claim:
A clutch assembly for an electric 4-wheel drive system for selectively blocking power delivered from a drive element of a motor to a driven element of a rear wheel, the clutch assembly comprising: a one-way clutch movably installed between the drive element and the driven element; a fork member movably installed in a clutch housing and brought into sliding contact with an external circumference of the one-way clutch; and an actuator installed in the clutch housing and configured to provide forward working force and backward working force to the fork member, wherein the one-way clutch comprises a ratchet hinged to an inner race between an outer race and the inner race, wherein the one-way clutch is configured in a sprag method in which part of the ratchet is protruded into an interior circumference of the inner race, wherein the ratchet constrains a drive shaft of the drive element and a driven shaft of the driven element disposed coaxially with the drive shaft and the one-way clutch is moved between the drive shaft and the driven shaft by way of a forward drive of the actuator, wherein the ratchet is brought in a surface contact with exterior circumferences of the drive shaft and the driven shaft between the drive shaft and the driven shaft.