Cross-shaped slider 1, which has guides perpendicular to each other, moves along fixed guides p-p whose axis coincides with axis 0x. Slider 2 moves along fixed guides n-n whose axis makes the angle 45° with axis 0x. Cross-piece At of slider 2 has its axis parallel to axis 0y and is connected by a sliding pair to slider 1. Cross-piece Am of slider 2 has its axis parallel to axis 0x and is connected by a sliding pair to cross-shaped slider 4 which has guides perpendicular to each other. Slider 4 moves along fixed guides r-r whose axis coincides with axis 0y. Link 5 is connected by turning pair B to slider 1 and by a sliding pair to slider 3 which, in turn, is connected by turning pair C to slider 4. When slider 1 moves along guides p-p, points D and D' of link 5 describe branches q-q and q' -q' of a Dürer "conchoid" with the equation (x-y+a)²(b²-y²)=(b²-y²-xy)² where a=A͞͞E and b=B͞D=B͞D' are constant dimensions of the mechanism.
$1216$LG,Ge$