Fluid actuated press

Claim 1

IN A PRESS HAVING A STATIONARY BED, A PLURALITY OF VERTICAL GUIDE POSTS FIXED AT THEIR LOWER EXTREMITIES TO SAID BED, AND A RAM VERTICALLY SLIDABLY MOUNTED ON SAID DIRECTLY CONNECTED TO SAID POSTS AND DEFINING A DIE SET AREA WITH SAID BED, AND ACTUATOR FOR URGING SAID RAM TOWARD SAID BED, SAID ACTUATOR COMPRISING: A THRUST PLATE MOUNTED TO SAID POSTS ABOVE SAID RAM; MEANS OPERATIVE TO MAINTAIN SAID THRUST PLATE IN FIXED POSITION UPON SAID POSTS; A FLEXIBLE, UNARTICULATED BAG RESTING UPON SAID RAM AND CONNECTED TO SAID THRUST PLATE, THE MATERIAL OF SAID BAG HAVING AN ELECTRIC CHARACTERISTIC OF LONGITUDINAL EXPANSION WITHOUT SIGNIFICANT LATERAL EXPANSION UPON INTRODUCTION OF PRESSURIZED FLUID INTO SAID BAG; AND MEANS FOR INTRODUCING FLUID UNDER PRESSURE INTO SAID BAG WHEREBY SAID RAM IS URGED TOWARD SAID BED.