| 摘要 |
<p>The present invention relates to a crank assembly increasing rotation ratio which more increases the number of rotations of a rear wheel with respect to one rotation of a crank arm when a diameter of a sprocket installed in a crank shaft is regarded to be regular. The crank assembly increasing the rotation number, having the crank shaft supported at a shell arranged in a frame structure to be rotatable; and crank arms having one ends fixated on both ends of the crank shaft respectively to have their phases opposite to each other, is configured to comprise a planet gear carrier formed on one end of one side crank arm and having a planet gear concentrically arranged around the crank shaft; a sun gear having a tube shape where one side is fixated on one side of the shell and the other side wraps one side of the crank shaft at an interval, and having the outer circumferential surface engaged with the planet gear; and a ring gear rotationally supported on the outer circumferential surface of the sun gear, having the inner circumferential surface engaged with the planet gear, and including one or more sprockets on the outer circumferential surface, wherein the diameter of the sun gear is greater than that of the planet gear.</p> |
