This mechanism is similar to those in models S-27 and S-28. Straight-line motion is affected by the rolling of a toothed cylinder sector on straight rack gearing. A form of this mechanism was used in steam engine design in the 18th century. The involute is a curve generated when a tension band is unwrapped from a circular cylinder similar to the rolling of a circle on a line. The Voigt catalog attributes this mechanism to Franz Reuleaux himself along with the mechanisms in models S-27, S-28.

Francis Moon 2004-07-00