The lengths of the linkscomply with the condition: A͞C > A͞B. Link 1, rotating about fixed axis A, has pin a which slides along slot b of slotted link 2. Slotted link 2 makes complete revolutions about axis B.

Testtext:
Angle γ
Slotted link 1 has the form of a disk with three equally spaced diametral slots a and rotates about fixed axis A. Link 3, rotating about fixed axis B, carries three rollers 2 located on diameter d 2*A͞B at angles of 120° to one another. The provision of three slots a ensures equal force distribution and smooth motion of the mechanism. When link 3 rotates clockwise, rollers 2 slide along the diametral slots of link 1, rotating it in the same direction. The transmission ratio between links 3 and 1 equals i₃₁ = ω₃/ω₁ = 2. Thus the angle of rotation of link 3 is always that of link 1.