Slider 1 moves along fixed guides t-t whose axis passes through point G and makes the angle ϕ with axis Ox. Slider 1 is connected by turning pair M to link 3 having the form of a bent lever with the angle dMf equal to ϕ. Arm Md of link 3 moves in slider 4 which turns about fixed axis F. Arm Mf of link 3 moves in cross- shaped slider 2 which has guides perpendicular to each other. Sliders 5 and 6, connected together by turning pair P, move along cross-pieces Mn and Fm of sliders 1 and 4. Point F is placed at the focus of a parabola and point G is located on axis Oy (passing through vertex 0 of the parabola) at the distance G͞0 equal to G͞0=0͞F/tan(ϕ)=p/2*tan(ϕ) where p is the given distance between the focus of the parabola and its directrix. Then, when slider 1 moves along guides t-t, straight line Mf envelops parabola q-q and point B of slider 2, at the intersection of axes Pk and Mf, describes parabola q-q.
$1107$LG,Ge$