Multi-ratio transmission system with parallel vertical and coaxial planet gears

A multi-ratio transmission system with parallel vertical and coaxial planet gears, comprising:

• a plurality of planet gear sub-systems, being coaxially disposed in series along a first axis, each of said planet gear sub-system comprising:
• a sun gear, being coaxially disposed along said first axis, wherein said sun gear rotates around said first axis optionally;
• and
• at least one planet gear, being coaxially disposed along a second axis which is vertical to said first axis, wherein said at least one planet gear rotates around said second axis;
• a coupling assembly disposed between every two adjacent said planet gear sub-systems so as to transmit rotation of said planet gear of the former said planet gear sub-system to said planet gear of the latter said planet gear sub-system;
• a setting element disposed corresponding to each of said planet gear sub-systems, wherein said setting element optionally moves in the direction of said first axis so as to optionally engage with said sun gear of said planet gear sub-system;
• a setting element controller, having a hollowed tube disposed coaxially with said first axis to rotate around said first axis within a range of predetermined angles, wherein said hollowed tube has an outer circumferential surface, and a cam groove is formed on said outer circumferential surface in the circumferential direction corresponding to each of said setting element of said planet gear sub-system, thereby allowing said setting element to optionally move along said first axis and to optionally engage with said sun gears of said planet gear sub-systems;
• an annular gear engaged to said planet gear of at least one said planet gear sub-system;
• a cylindrical casing enclosing said planet gear sub-systems, wherein said cylindrical casing has a front end for installing said annular gear;
• a sprocket, installed onto said planet gear sub-systems through a one-way clutch, wherein said sprocket is installed with an external transmission system to drive said planet gear sub-systems to rotate;
• and
• a central axle, being disposed coaxially with said first axis, wherein said central axle is inserted into a center through hole of said hollowed tube of said setting element controller by relative rotation, thereby enabling said hollowed tube to rotate around said central axle.