Chebyshev linkage

The Chebyshev mechanism, also called Chebyshev - parallelogram ( in transcriptions, there are also the spellings Chebyshev, Chebyshev or Chebyshev ), is a tripartite linkage, which converts the rotary motion into an approximately straight line. It was discovered by the Russian mathematician Chebyshev Pafnuti Lvovitch who explored the theoretical problems of kinematic mechanisms, in the 19th century. The conversion of a rotational movement into a linear movement is a part of the more general problem of converting a rotational movement into a desired movement.

The area of ​​the rectilinear motion is defined by the point - the center of the rocker - which moves between the two end points of this transmission. On this route the deviation from the ideal linear motion is low.

The ratio between the lengths corresponds to the following expression:

Follows from the illustrated relationship, the arm is vertical, if this is arrived at one of the end points of its movement.

Mathematics are the lengths in the following relationship: