Pulleys 1 and 3 rotate about fixed axes B and C. Driven pulley 5 rotates about axis A of movable bearing housing 2. Pulley 4 rotates about axis D of housing 2. Endless flexible link 6 runs over all four pulleys. When pulley 1 rotates about axis B, all the other pulleys rotate about their axes, and bearing housing 2 can be moved to any position along fixed guide a.
$3582$CFL,DF$