Bike, perhaps the most common vehicle. And the fact that the most economical — there is no doubt that only two sandwiches to two hours to pedal. But is it possible to increase the efficiency of the human “engine”? With the reduction of spending “fuel”, nothing happens. Friction and the weight of the machine is reduced almost to a minimum. There is also a “box of speeds” the device for changing the gear ratio by switching the circuit to a small or large sprocket. It remains only to lengthen the levers of the pedals, but experts adamantly claim that their optimal length — 170 mm.
An original solution was proposed in recent years elliptical sprocket. Readers familiar with the details of this invention. Using the ellipse ratio is changed cyclically, better adjusting of the pedal mechanism under the human, but… not easier work.
In the present device (Fig. 1) UDA the axis to synthesize the advantages of elliptical gears and a “long” levers: here the torque increases when under pressure from the charm levers like extended, describing at the same time Ellipso curve, although the drive sprocket maintains the correct circumference. This achieves a gain in power and eliminates the uneven change of the transmission ratio; the legs describe a circle of optimal radius of 170 mm.
Fig. 1. Here is a new pedal mechanism:
1 — the bike frame 2 — front wheel 3 drive sprocket, 4 — foot extra leverage, a 5 — star lever, 6 — additional chain transmission, 7 — rod, 8 — bracket.
The pedal mechanism (Fig. 2) there has not been without the usual main lever — rod 4, on the hub which fits over the auxiliary sprocket 9. It is mounted in a fixed position relative to the Bicycle frame through the bracket 11. To the free end of the connecting rod hinge is mounted on the auxiliary extension arm 12 to the pedal 13. On the selector shaft 12 fixed to the second auxiliary sprocket 14. Both gears have the same number of teeth and are linked by a chain.