Patent ID: 8977450
Filing Date: 2015-03-10
Classification: B62M

Abstract:
1. An automatic gear-shifting bicycle with optimal shift timing, comprising: a bicycle body comprising a bottom bracket bearing axle, two cranks respectively coupled to said bottom bracket bearing axle, a pedal supported on each said crank, and a derailleur; a power supply module installed in said bicycle body; a microcomputer electrically coupled to said power supply module; a gear shifting control driver electrically coupled to said microcomputer, and controllable by said microcomputer to drive said derailleur to change gears; and a pedal position sensor module installed in said bicycle body corresponding to at least one said crank and electrically coupled to said microcomputer, enabling said microcomputer to determine the angular position of at least one said crank and the pedaling direction of at least one said crank to be forward pedaling or backward pedaling; wherein, when a person riding the automatic gear-shifting bicycle is pedaling said pedals, said microcomputer determines the optimal shift timing subject to one of the conditions: (1) sensing the angular position of at least one said crank at a predetermined location during forward pedaling and a related time point, and enabling said microcomputer to calculate, subject to the sensed angular position and the related time point, an estimated pedaling speed during forward pedaling and then calculating a calculated time point in which at least one said crank will next pass a pedaling dead point, wherein the pedaling dead point is 0° angle position or 180° angle position from the horizontal plane, and using the calculated time point as the optimal shift timing; or (2) sensing a sensed time point each time at least one said crank reaches the pedaling dead point during forward pedaling, and using the sensed time point as the optimal shift timing; or (3) sensing a backward pedaling of at least one crank, and judging a time point to be the optimal shift timing when a backward pedaling of at least one crank is sensed.