Thermoforming Apparatus Having Adjustable Length Load Shafts and Method

Abstract

A thermoforming machine is provided having a load shaft end adjustment apparatus. The thermoforming machine load shaft end adjustment apparatus includes a load shaft, a backlash nut, a height adjustment nut, a collar, and at least one fastener. The load shaft has a threaded end segment and an axially extending key slot. The backlash nut is threaded onto the end segment. The height adjustment nut is threaded onto the end segment adjacent the backlash nut. The collar is configured to receive the height adjustment nut for rotation, having a key configured to be received within the key slot, and is configured to be mounted onto a platen of the thermoforming machine. At least one fastener extends between the backlash nut and the collar and is configured to secure together the backlash nut and collar with the height adjustment nut interposed there between. A method is also provided.

1 - 20 . (canceled) 
     
     
         21 . A thermoforming machine load shaft apparatus, comprising:
 a load shaft configured to engage between a pair of thermoforming platens of a thermoforming machine to carry forming loads between the pair of platens during a thermoforming operation;   a first structural support provided on the load shaft at a first location configured to mate with a first platen of the pair of platens;   a second structural support provided on the load shaft at a second location configured to mate with a second platen of the pair of platens and spaced from the first location with the length adjustment segment provided between the first location and the second location; and   a length adjustment mechanism carried by one of the load shaft and one of the pair of platens movable to effect length adjustment of mating fitment between the pair of platens as engaged together along the load shaft during application of forming loads.   
     
     
         22 . The thermoforming machine load shaft apparatus of  claim 21 , wherein the length adjustment mechanism is carried by the load shaft. 
     
     
         23 . The thermoforming machine load shaft apparatus of  claim 22 , wherein the length adjustment mechanism comprises a preloaded compression mechanism. 
     
     
         24 . The thermoforming machine load shaft apparatus of  claim 23 , wherein the length adjustment mechanism comprises a threaded segment provided on the load shaft and a length adjustment nut threaded onto the threaded segment of the load shaft proximate the first structural support and movable to effect length adjustment of the load shaft proximate the first structural support and movable to effect length adjustment of the load shaft as engaged between the pair of platens. 
     
     
         25 . The thermoforming machine load shaft apparatus of  claim 24 , wherein the length adjustment mechanism comprises at least one fastener extending between the first structural support and the first platen and configured to secure together the first structural support and the first platen and further comprising a length adjustment nut interposed there between and engaged in threaded relationship to impart a preload that urges the length adjustment nut against the collar that is greater than a load received by the load shaft as thermoforming pressure is applied between the platens. 
     
     
         26 . The thermoforming machine load shaft apparatus of  claim 21 , wherein the first structural support comprises a mechanical coupling system configured between the load shaft and the first platen. 
     
     
         27 . The thermoforming machine load shaft apparatus of  claim 26 , wherein the second structural support comprises a mechanical coupling system configured between the load shaft and the second platen. 
     
     
         28 . The thermoforming machine load shaft apparatus of  claim 27 , wherein the first structural support and the second structural support each comprise a mechanical coupling system having an array of dog legs provided on the load shaft and a complementary locking collar provided on the respective platen. 
     
     
         29 . A thermoforming machine, comprising:
 a frame;   a first thermoforming platen;   a second thermoforming platen;   a drive mechanism configured to move the first platen relative to the second platen in reciprocation;   a load shaft configured to engage between the platens to carry forming loads between the pair of platens during a thermoforming operation;   a first structural support provided on the load shaft at a first location configured to mate with a first platen of the pair of platens;   a second structural support provided on the load shaft at a second location configured to mate with a second platen of the pair of platens and spaced from the first location with the length adjustment segment provided between the first location and the second location; and   a length adjustment mechanism carried by one of the load shaft and one of the pair of platens movable to effect length adjustment of mating fitment between the pair of platens as engaged together along the load shaft during application of forming loads.