Patent ID: 7083164
Filing Date: 2006-08-01
Classification: B21D,F16F

Abstract:
1. A cushion for a ram or bolster of a metal stamping press, said cushion comprising; a manifold comprising fluid-flow passages and a plurality of cylinder mounting locations each in communication with at least one of the fluid-flow passages; a plurality of cushion cylinders located respectively in said plurality of cylinder mounting locations, each cushion cylinder comprising: a cylinder body comprising an inner wall that defines a bore having a diameter D; a piston located in said bore and comprising opposite inner and outer faces, wherein said outer face is oriented outwardly relative to said bore and said manifold; a fluid seal supported on said piston and slidably engaged with said inner wall defining said bore; first and second axially spaced-apart bearings supported on said piston and slidably engaged with said inner wall defining said bore, said first and second bearings cooperating to support said piston slidably in said bore for reciprocal sliding movement between an extended position, where said piston is located adjacent an outer end of said cylinder body, and a retracted position, where said piston is moved axially into said bore away from said outer end of said cylinder body, said bearings defining inclusively therebetween a bearing-length L that is less than or equal to 40% of said bore diameter D, wherein said piston comprises a cylindrical periphery on which said first bearing is received, and wherein said second bearing is immovably held between said piston and a bearing retainer that is fixedly secured to said piston, and wherein said second bearing of each of said plurality of cushion cylinders comprises an annular disc member including a central opening defined therein, said bearing retainer of each of said cushion cylinders comprising: (i) a retainer body received in said central opening of the second bearing and fixedly secured to said piston; and, (ii) a flange that projects outwardly from said retainer body and that engages and clamps said second bearing between the flange and the piston.