Frost & Jacobs
Die assembly for use in general type mechanical press machine
 A die assembly for use in a general type mechanical press machine has opposite upper and lower dies adapted to be fitted in upper and lower die sets, respectively, so as to be slidable freely by a predetermined stroke, and a differential mechanism interposed between the upper and lower dies so as to transmit a predetermined rate of displacement to the lower die in accordance with the movement or displacement of the upper die set. The differential mechanism comprises a rack and pinion mechanism or linkage having two pair of link mechanisms. 
Kabushiki Kaisha Komatsu Seisakusho
B B B B
B30B B21J B30B B21J
inventional inventional inventional inventional
Yasuo Chieo
Suzuki Urata