Model: W05 Friction Wheels with Transverse Axes and Grooved Wheel
In distinction to the other friction wheel mechanisms in this series, the axes of the two wheels are transverse to one another at an angle of 90 degrees. A single groove is placed in the smaller diameter wheel with a 'vee' shaped geometry. The groove allows a larger contact area as well as permits the required normal force to be created with either forces along or transverse to either wheel axis. A toothed wheel solution to crossed axes motion would require bevel gears. Reuleaux called this particular device a "conical friction wheel" and the general class of friction wheels, "force closed" mechanisms.

Francis Moon 2003-07-01

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