Double crank 1 rotates about fixed axis A and carries two rollers 3. Cam disk 2 rotates about fixed axis B and has internal contour a composed of three symmetrically arranged portions. When crank 1 rotates, rollers 3 roll along contour a, rotating disk 2 in the same direction. Continuous rotation of disk 2 is due to the provision of two rollers 3. The speeds n₁ and n₂ of crank 1 and disk 2 (in rpm) are related by the equation n₂=(2/3)n₁.
$3009$SmC,3L$