High speed web stopping mechanism

Claim 1

WEB PUNCHING MECHANISM FOR OPERATING ON A CONTINUOUSLY FED WEB, SAID MECHANISM COMPRISING A VERTICALLY RECIPROCABLE PUNCH PRESS AND DIE REQUIRING AN INTERMITTENT WEB FEED, AND MEANS FOR ALTERNATELY STOPPING AND ACCELERATING THAT PORTION OF THE WEB WHICH IS IN THE DIE, SAID MEANS INCLUDING A FIRST IDLER NEAR THE BOTTOM OF THE PRESS COOPERATING WITH TWO COLLATERAL SPACED DIRECTIONCHANGING ROLLERS THEREABOVE AT THE DIE HEIGHT TO FORM A GENERALLY UPRIGHT REVERSE LOOP OF WEB AHEAD OF THE DIE, SAID IDLER BEING LOCATED IN AND FORMING THE LOWER END OF THE LOOP, A SECOND SIMILAR IDLER NEAR THE BOTTOM OF THE PRESS COOPERATING WITH TWO COLLATERAL SPACED DIRECTION-CHANGING ROLLERS THEREABOVE AT THE DIE HEIGHT TO FORM A SECOND SIMILAR GENERALLY UPRIGHT REVERSE LOOP OF WEB FOLLOWING THE DIE, THE SIDES OF THE SAID LOOPS BEING APPROXIMATELY PARALLEL, AND HAVING A VERTICAL DIMENSION WHICH IS LARGE RELATIVE TO THE ECCENTRICITY IN ORDER TO MINIMIZE THE PROBLEM OF ANGULARITY AS THE LOOP IS OSCILLATED BY THE IDLER, A SHAFT CARRYING SAID FIRST IDLER ECCENTRICALLY, A SHAFT CARRYING SAID SECOND IDLER ECCENTRICALLY, MEANS GEARING SAID SHAFTS TOGETHER FOR CONTINUOUS EQUAL ROTATION IN OPPOSITE PHASE SO THAT ONE LOOP IS LENGTHENED WHILE THE OTHER IS SHORTENED, SAID IDLERS HAVING THE SAME RADIUS OF ECCENTRICITY SO SELECTED THAT THE WEB IS STOPPED AT DESIRED PITCH LENGTH, GEARING FOR DRIVING ONE OF SAID DIRECTION-CHANGING ROLLERS AHEAD OF THE DIE AND ONE FOLLOWING THE DIE IN TWOTO-ONE RATIO RELATIVE TO THE ROTATION OF THE SHAFTS CARRYING THE ECCENTRIC LOOP-FORMING ROLLERS, THE SAID DRIVEN DIRECTION-CHANGING ROLLERS BEING SLIGHTLY ECCENTRICALLY MOUNTED, THE AMOUNT OF ECCENTRICITY AND THE PHASE RELATION OF THE SAID DRIVEN DIRECTION-CHANGING ROLLERS BEING SUCH AS TO COMPENSATE FOR THE ANGULARITY OF THE LOOPS CAUSED DURING REVOLUTION OF THE ECCENTRIC LOOP-FORMING IDLERS.