Torque Sensing Gear Structure of an Electronic Bike

A torque sensing gear structure comprising:

• a main sprocket base being a holder for fastening at least a driving sprocket of a bicycle, an external ring of the main sprocket base extended and disposed with a plurality of fastening racks, a shaft hole piercing through the main sprocket base to provide a stepping shaft of the bicycle passing thereto, a connection ring structure forwardly extended and disposed to the main sprocket base, an external ring wall surface of the connection ring structure disposed with a plurality of snap blocks mutually spaced, an arrangement space formed between the snap blocks, a flexible element arranged in the arrangement space, a snap slot concavely disposed to each snap block at a same turning place, a bottom wall of each snap slot disposed with a sliding hole, a first ring groove concavely disposed to a rear sidewall surface of the main sprocket base, the first ring groove overlapped in each sliding hole, a second ring groove corresponding to an inner side of the first ring groove further concavely disposed and concentrically arranged together with the first ring groove;
• a first magnetic ring correspondingly disposed in the first ring groove, a plurality of first magnetic members disposed at a same interval apart on the first magnetic ring, a guide column corresponding to each sliding hole further fastened to the first magnetic ring, each guide column passing through the sliding hole and extended to the snap slot;
• a second magnetic ring correspondingly fastened in the second ring groove, in which a plurality of second magnetic members identical in quantity as the first magnetic members are distributed at equal intervals;
• a shaft disc rotably fit to the connection ring structure, a via hole disposed thereon, the via hole correspondingly fit to the stepping shaft of the bicycle, an unidirectional clutch bearing disposed inside the shaft disc so that the stepping shaft of the bicycle drives the shaft disc to unidirectionally rotate in the stepped rotational direction, a fastener corresponding to each snap slot disposed to a rear sidewall of the shaft disc, the fastener extended and passing through the snap slot, the fastener moving towards an exterior of the snap slot and pushing the flexible element when the stepping shaft of the bicycle is stepped to rotate, the flexible element compressing and pushing the main sprocket base to drive the main sprocket base to rotate, the fastener disposed with a guide hole, the guide hole correspondingly fit to the guide column;
• and
• a sensing unit correspondingly disposed to a rear side of the first magnetic ring and the second magnetic ring, wherein when the stepping shaft of the bicycle is stepped to rotate to drive the bicycle to advance forward, the sensing unit is capable of sensing a moving distance of the second magnetic ring lagging behind the first magnetic ring during rotation, which is a length that the flexible element is compressed .