Question

Explain the mechanical advantage and transmission angle of four bar chain with neat sketch.

Answer 1

A four-link mechanism with four revolute joints is commonly called a four-bar mechanism.

Application of four-bar mechanisms to machinery is numerous. Some typical applications will involve:

a) Correlation of the angular rotations of the links connected to the fixed link (commonly known as correlation of crank angles or function generation). In such applications we would like to have a certain functional relation such as q14 = f(q12) to be realised by the four-bar mechanism. A simple example will be to convert a linear scale to a logarithmic scale within a certain range