Rotary capping apparatus and feedback control system for regulating applied torque

A rotary capping apparatus for applying screw-on type caps to containers, said apparatus comprising:

• a primary supporting frame having a plurality of vertical leg members;
• a cap driver assembly including an inflatable gripping means for application of a predetermined torque to the screw-on type caps, said cap driver assembly being mechanically coupled to said capping head;
• primary height adjusting means for imparting vertical movement to said capping head;
• a driving means including a servomotor for transmitting a predetermined torque to said cap driver assembly, said driving means being mounted on said height adjusting means and mechanically coupled to said capping head;
• container indexing means mechanically attached to said driving means for synchronous advancement of said containers to said cap driver assembly for torquing;
• a capping head disposed in vertically adjustable relation to said primary supporting frame, wherein said capping head includes a housing containing a gear mechanism and at least one input shall having a hollow core for transmission of torque from said driving means to said cap driver assembly, said core being disposed in fluid communication with an inflatable gripping means permitting the flow of compressed air and vacuum thereto, wherein said at least one input shaft is mechanically connected to said driving means by an axially extensible spine mechanism that permits simultaneous rotation and vertical extension of said at least one shaft during operation of said driving means;
• and
• closed loop controlling means for applying said predetermined torque further including:
• (a) a central processing unit for conducting proportional, integral, and derivative control calculations,
• (b) an operator console for setting parameters that govern application of said torque transmitted by said cap driver assembly to said caps, and
• (a) a servocontroller interfaced for bidirectional communication with said central processing unit, said servocontroller generating an output signal to said servomotor based on the position of said cap driver assembly for torquing said caps such that said predetermined torque is attained.