A handle assembly includes a handle shaft portion, a handle arm, a handle grip, and a tubular member. The handle shaft portion is mounted to the inner peripheral portion of a master gear shaft so as not to be allowed to rotate relative to the master gear shaft, and is disposed so that the tip end portion of the master gear shaft protrudes outward in the axial direction compared to the tip end portion of the master gear. The handle arm extends in the radial direction from the tip end portion of the handle shaft portion, and is mounted to the handle shaft portion so as to be capable of pivoting with respect to the handle shaft portion. The handle grip is mounted to the tip of the handle arm. The tubular member is non-rotatably engaged with the tip end portion of the master gear shaft and the base end portion of the handle arm.
