Patent ID: 7779979

Claim:
A synchronizing device for a manual transmission for synchronizing rotation speeds of a rotating shaft and a shift gear, the synchronizing device comprising: at least one first ring disposed on an exterior circumference of the rotating shaft and having an exterior sloped surface at its exterior circumference; at least one second ring disposed on an interior circumference of the shift gear and having an internal sloped surface contacting the exterior sloped surface of the first ring; and an actuator unit selectively applying an axial directional load to the at least one first ring or the at least one second ring so as to engage the shift gear or release the shift gear from the rotating shaft by frictional force between the first and second rings, wherein the synchronizing device comprises a plurality of first rings and a plurality of second rings, and a first supporting step is formed on the exterior circumference of the rotating shaft so as to support an innermost first ring opposite to the actuator unit among the plurality of first rings; and a second supporting step is formed on the interior circumference of the shift gear so as to prevent escape of an outermost second ring close to the actuator unit among the plurality of second rings.