Link 2 rotates about fixed axis z-z, parallel to axis Oy, and is connected by a screw pair to link 3 which has pin a sliding along slot b of link 1. Link 1 turns about fixed axis O. Displacement y of nut 3 is proportional to the tangent of angle ϕ, i.e. y=k tan(ϕ), where k is a constant dimension of the mechanism.
$2258$LS,MO$