New technique for the propulsion of a machine a three-

摘要

The invention relates to a device bringing novel technology into the propulsion of vehicles with pedals. It consists of a chain wheel 1 fixed to a chain wheel spindle 2, of two pedal cranks, a right-hand one 4 and a left-hand one 5 which are not fixed to the chain wheel spindle but each connected to this spindle by a so-called free wheel system. To the upper part in front of the spindle of each pedal crank 3 is articulated a vertical spindle or connecting rod 9 to the right, and 10 to the left connected to the end of a balance arm 11, the centre of which is articulated to the front face of the part of the frame which connects the chain wheel to the saddle. The connecting rods and balance beam together impart to the pedal cranks, when one of them starts to move, a reciprocating up and down movement, each one describing a circular arc of 90 DEG . The device according to the invention is particularly intended for the propulsion of bicycles. IMAGE