Patent ID: 7445223

Claim:
A bicycle drive unit that moves forward and backward and idles upon clockwise and counterclockwise pedaling, comprising: a drive shaft 1 having one end located in an inner bearings B 1 of an internal bearing housing H 1 integrally formed with a rotary plate 5 and the other end fixed to a clockwise one-way clutch C 1 and the inner wheel of a counterclockwise one-way clutch C 2 by means of a sunk key 2 ; a counterclockwise one-way clutch C 2 having a central gear 7 press-fitted on its outer wheel, wherein a plurality of turnabout gears 8 engaged with the central gear 7 are coupled to the rotary plate 5 by means of a fixed pin 9 ; a ring gear 10 engaged with the turnabout gear 8 and having a chain sprocket 4 attached on its outer circumference; a flange 23 connected to a ring gear 10 by means of a locking screw 22 and having an inner circumference press-fitted into the outer wheel of the clockwise one-way clutch C 1 ; a bearing housing of a dual structure consisting of an outer bearing housing H 2 having outer bearings B 2 , wherein the outer bearings B 2 are rotated together with the internal bearing housing H 1 in a backward movement; a brace 17 attached to the outer circumference of the outer bearing housing B 2 by means of the locking screw 22 ; a detent pin unit for curving the internal bearing housing H 1 and the rotary plate 5 , wherein the detent pins 11 within the detent pin guide 13 is introduced into the detent plate 16 attached to the internal bearing housing H 1 by means of the return spring 12 as the hand lever 19 is relaxed; and a bicycle backward movement control unit having a hand lever 19 and a detent latch 20 , wherein the hand lever 19 is connected to the detent pins 11 by means of a steel wire 18 and is fixed to a steering handle tube 30 by means of a clamp 21 , and the detent latch 20 is attached to the hand lever 19 .