The lengths of the links comply with the condition: A͞B=B͞C. Link 2 is connected by turning pairs B and C to crank 1 and slider 3 which moves along fixed rod 4. Link 2 can be clamped in various positions by means of screws c and d. When crank 1 rotates about fixed axis A, point P describes an ellipse whose parameters can be varied by changing the position of point P. This is done by means of clamping screws c and d at points B and C.
$1606$SC,Ge$