The mechanism is driven by angular crank 4 whose design is shown separately (unit a). Rotation of crank 4 about axis y-y, is converted by slider 1 and spherical sleeve 2 into oscillation of slotted link 3 and lever 5 about fixed axes A and B. The stroke of the hammer can be varied by adjusting slider 1 along axis y-y. Spring 6 is both an elastic link and a shock absorber. Lever 5 is connected at point C by a sliding pair to link 7 which is designed as a sphere that turns free y in the hollow spherical surface of link 8.
$1324$LG,HP$