Patent ID: 8302284

Claim:
An apparatus for securing at least one end cap including an end cap flange to a shell including a shell flange by forming a lip portion comprising the end cap flange and the shell flange into a lock seam portion in which the end cap flange and the shell flange are engaged with each other, the apparatus comprising: an elongate tool element at least partially defined by a central axis thereof and rotatable about the central axis, the tool element being adapted for receiving said at least one end cap thereon; said at least one end cap being adapted to receive at least part of the shell thereon to locate the shell flange in a predetermined position relative to the end cap flange; a plurality of roller subassemblies for forming the lip portion into the lock seam portion, each said roller subassembly comprising a forming roller engageable with the lip portion while the tool element rotates; each said roller subassembly additionally comprising an arm on which said forming roller thereof is rotatably mounted, and a support mechanism for positioning the arm to engage the forming roller with the lip portion; a hydraulic system comprising: a hydraulic fluid; a pump for utilizing energy inputs therein to subject said hydraulic fluid to positive pressure in a positive direction relative to the pump; a plurality of hydraulic cylinders, said hydraulic cylinders being the support mechanisms of the roller subassemblies respectively, each said hydraulic cylinder being in fluid communication with the other said hydraulic cylinders and with the pump; and each said hydraulic cylinder being adapted to subject said hydraulic fluid to alternating positive pressures and negative pressures in a negative direction opposite to the positive direction as the tool element rotates, the forming rollers being positioned relative to the central axis and relative to each other such that the positive and negative pressures at least partially offset each other, for optimizing said energy inputs.