Patent ID: 7594334

Claim:
A portable brush cutter including an elongated member, the brush cutter comprising: a cutting blade mechanism at a distal end of the elongated member; and a prime mover including an output shaft for driving the cutting blade mechanism via a transmission shaft installed inside the elongated member at a proximal end thereof; a vibration-absorbing coupler interposed between the output shaft of the prime mover and the transmission shaft, the coupler comprising: a torsion coil spring; a regulator to regulate the rotation of the torsion coil spring to prevent the spring from twisting more than a predetermined amount; a movable sleeve having spline female teeth which are slidably engaged with spline male teeth formed on the transmission shaft; and a cylindrical connector which is adapted to be rotated with the output shaft and in which the movable sleeve is slidably inserted; wherein the torsion coil spring is interposed between the movable sleeve and a spring shoe attached to the cylindrical connector, one end portion of the torsion coil spring being anchored to an anchor portion provided in the spring shoe and the other end portion thereof being anchored to an anchor portion provided in the movable sleeve; and the regulator is mounted on both of the movable sleeve and the cylindrical connector.