A push button controlled means of orienting tubular film printed in the layflat for post-print gusseting.
The Bubble Rotator consists of an infeed turning bar that is Silverstone coated and has air vents to provide an air cushion for the film to easily slide over the bar. The turning bar has a screw adjustment for width of active air area to conserve plant air. The discharge nip roll assembly of the bubble rotator contains the inflated bubble between itself and the bottom nip rolls in the post-gusseter. The turning bar and the nip rolls are mounted on separate frames carried on a rotating hub that is mounted to a crossmember at the top of the post-gusseter tower.
A motor and reduction gearbox assembly and chain drive are provided to turn the turning bar at 1/2 the angular displacement of the nip rolls. The motor is controlled by push-buttons to allow the operator to easily change the orientation of the printed film to the gusseter. A torque limit clutch is provided to protect the assembly if the film should catch in the bubble rotator.
The film is printed in the layflat, fed into the Bubble Rotator over the turning bar, through the nip roll assembly, re-inflated, and fed through the gusseter. The printing is oriented by changing the turning bar and nip roll angles to the incoming and outgoing sheet.
Solenoid valves and regulators with push-button controls are provided for opening and closing the nip rolls for thread-up and regulating the pressure between the rolls.