Links 1 and 2 have straight-line motion in guides c. At this, link 3 is displaced in guide d and rollers a slide along slots b. The linear displacement x of link 3 is expressed by the equation x=(a₁/(a₁+a₂))x₁+(a₁/(a₁+a₂))x₂ where x₁ and x₂ are linear displacements of links 1 and 2. Thus, the mechanism adds two quantities x₁ and x₂ which are entered as displacements of links 1 and 2.
$1256$LG,MO$