When tracing point F is moved along curve y=f(x), guide rollers 3 and 3', connected by link b, travel along axis x-x. Attached to roller 3 is gear 4 which meshes with gear 4', rotating about axis T of link b. Rigidly attached to gear 4' is disk a along which recording wheel 2 rolls. The angle of rotation a of wheel 2 is proportional to the area A of the figure around which point F has been traced: α=cA=c∮(f(x))dx. When lever 1 is turned about point D, wheel 2 does not turn about its axis.
$3441$CF,MO$