The lengths of the links comply with the condition: A͞C=C͞B=B͞D=D͞A. Link 1 rotates about axis x-x and is connected by screw pairs to links 3 and 4 which, in turn, are connected by turning pairs A and B to links 5, 7, 6 and 8. The bearings of link 1 are mounted in slides 9 and 10 which move vertically along fixed guides p-p. Slide 2 moves along fixed guides p-p and is connected by turning pair D to links 7 and 8. Links 5 and 6 turn about fixed axis C. Screw 1 has right- and left-hand threads, a and b, of equal pitch. When link 1 is rotated, link 2 slides along guides p-p.
$2243$LS,HP$