Oblon, Spivak, McClelland, Maier & Neustadt
Punch press with independently operated pressing units driven by a crankshaft
 A punch press includes a driving crankshaft and a plurality of independent punch pressing units. The crankshaft has a plurality of angularly spaced eccentric sections. Each of the punch pressing units includes a slide, a coupler interconnecting the slide and one of the eccentric sections of the crankshaft, a punch carried on the slide, a die set, and a workpiece gripping unit. 
San Shing Hardware Works Co., Ltd.
B B
B30B B21D
inventional inventional
Yuan-Ho
Lee