| 摘要 |
1. Drive device, in particular for bicycles, with - a chain wheel (2), which is rotatable around a first straight line (T) perpendicular to the chain wheel plane, and with - two tread cranks (3a, 3b) disposed on the two sides of the chain wheel (2), of which tread cranks (3a, 3b) the one tread crank (3b) can be rotated around a second straight line (D) disposed perpendicular to the chain wheel plane, which straight line (D) is staggered versus the first straight line (T), characterized in that - the other tread crank (3a) is solidly connected with the chain wheel (2), - the chain wheel (2) exhibits different radii relative to the first straight line (T), - the other tread crank (3a) is inclined relative to the maximum radius (Rmax) of the chain wheel (2) in forward direction by an angle (alpha) of 45 to 135 degrees, - the second straight line (D) is staggered versus the first straight line (T) on a horizontal running in the chain wheel plane in horizontal position of the other tread crank (3a), where the one tread crank (3b) extends also at least approximately in horizontal direction, - the one tread crank (3b) is coupled with the other tread crank (3a) via an axle (A) solidly connected with accopling lever (5) and passing through the chain wheel (2) as well as oblong hole or, respectively, sliding guide (6) for receiving the relative motion between the two tread cranks (3a, 3b), and that - chain tensioning means is present for tensioning a chain (3) disposed on the chain wheel (2). |
