Patents Assigned to Sterling Tool Co.
  • Patent number: 4823661
    Abstract: A die assembly for mounting in a die press operates to punch a row of holes in a stack of paper sheets in response to a single press stroke. The die assembly comprises a stationary lower die block having a row of die holes therethrough, one or more lubricated stationary guide plates each having a row of guide holes therethrough and located above and spaced from the die block by a separator plate so as to define a stack-receiving slot, a reciprocably movable punch retainer assembly located above the guide plate and a row of elongated, downwardly-depending punches connected at their head ends to the punch retainer assembly which extend through and slidably engage the guide holes. When the press closes, the cutting ends of the punches move through the stack-receiving slot and through a stack of sheets therein into sliding engagement with the die holes. When the press opens, the punches are withdrawn clear of the stack-receiving slot.
    Type: Grant
    Filed: December 23, 1987
    Date of Patent: April 25, 1989
    Assignee: Sterling Tool Co.
    Inventor: Donald E. Freres