Head b of the hammer slides in fixed guide a and has flat board 2 which is clamped between friction driving roll 3 and pressure roll 4. Roll 3 rotates about fixed axis A, and roil 4 about axis B of lever 1 which turns about fixed axis C. Head b is raised by the continuously rotating friction roll 3 with lever 1 in the position shown. When lever 1 is turned clockwise, head b drops by gravity, imparting a blow on the work which lies on the anvil.
$3459$CF,HP$