METHOD AND APPARATUS OF FEEDING MATERIAL FOR PROGRESSIVE PUNCHING

摘要

METHOD AND APPARATUS OF FEEDING MATERIAL FOR PROGRESSIVE PUNCHING In a method of feeding a band-shaped sheet material in a progressive punching process, a finger provided downstream of a punching station adapted to progressively punch the sheet material is moved backwardly by one pitch in synchronization with the downward movement of a ram and is then moved forwardly by one pitch in synchronization with the upward movement of the ram, to pull-feed the sheet material engaged with the finger by one pitch. An apparatus for practicing the method comprises the finger; means for moving the finger forwardly by one pitch in synchronization with the upward movement of the ram and for returning the finger to its original position in synchronization with the downward movement of the ram; and means for causing the finger returned to the original position to be engaged with a punched hole in the sheet material.