Friction disk 1 rotates about fixed axis A-A and its working surface is pressed against sharp-edged roller 2 which is a nut moving along fixed screw 4. Keyed to the shaft of disk 1 is bevel gear 6 which meshes with bevel gear 7. Gear 7 is rigidly attached to drum 5 and rotates about fixed axis B-B. When disk 1 rotates, roller 2 is rotated and moves axially, traversing carriage 3 along screw 4. At the same time, drum 5 rotates about axis B-B. The trace of stylus K on drum 5 is an exponential curve with the equation y=A*e^(((mp)/(πd))*x) where p is the thread pitch of the screw, d is the diameter of roller 2, and m is the proportionality factor relating the displacement of the drum surface, with respect to tracing point K, and the angle of rotation of disk 1. If the angle of rotation of disk 1 is φ and the relative displacement of the drum (circumferential length) is x, then m=φ/x.
$3432$CF,Ge$