Patent ID: 7988169
Filing Date: 2011-08-02
Classification: B62K,B62M,Y10T

Abstract:
1. A bicycle without a seat having a front wheel, a rear wheel, a steering bar, a steering axis, and a frame which assembles and supports the steering axis and the rear wheel, said bicycle comprising: a pedal axle assembly including a pedal axle fixed onto the frame, first and second guide members into which both cut ends of the pedal axle are assembled and which a pair of guide holes are respectively formed; a crankshaft assembly including a crankshaft which is fixed onto the frame and rotates, a crankshaft gear which is assembled on the crankshaft, and first and second crank cams on which there are attached, respectively, first and second protruding members which are respectively received into the first and second guide members; and a spindle assembly including a spindle which is fixed onto the frame, a spindle gear which engages with the crankshaft gear and rotates, and a spindle sprocket which is placed with the spindle gear and connected to a rear wheel sprocket by a chain; wherein the crankshaft and the crankshaft gear rotate simultaneously, and the spindle gear engages the crankshaft gear to rotate together; wherein said first protruding member of the first crank cam is laid at an angle of θ