| 摘要 |
The invention relates to an improved crank and more particularly, but not exclusively, to the cranks of a bicycle crank gear and to the bicycles provided with this crank gear. It is characterised in that: - on the one hand, instead of the free end 8 of the crank 7 essentially carrying a pedal 9 directly associated with the journal carried by the crank totally free to rotate about this journal and acting directly on the crank, the means 9 for supporting the foot is associated with the journal 10 by means of a connecting rod 11 which, at its big end 12, carries the said support means 9 whereas, at its small end 13, it is rotationally guided about the journal 10 and, - on the other hand, between the small end 13 of the connecting rod 11 and the bearing bush 3, is interposed a transmission 14 of ratio 1/1 making sure that as the crank 7 rotates, the connecting rod 11: . remains, starting from the journal, pointing in the same direction and, preferably towards the back of the bicycle with respect to the direction of forward travel and, . always maintains, with respect to the horizontal, a constant angle which is preferably substantially zero. <IMAGE>
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