Abstract: Method and apparatus for operating a corrugator wet end splicing of three short orders between a longer first order and a longer fifth order utilizes a primary splicer and a tandem splicer in which the first two short order webs from paper rolls on the tandem splicer can be prepared for splice while the first longer order is running by threading the first of the short order webs from the tandem splicer to the primary splicer for splice preparation on the primary splicer and preparing the second short order for splice on the tandem splicer. The first and second short order webs are spliced on the primary and tandem splicer, respectively, immediately after completion of the longer first order. The third short order web is provided by a fourth roll mounted on the roll stand for the primary splicer immediately after completion of the longer first order.

Abstract: A method for automatically setting the rider roll/glue applicator roll gap for the single face web on a glue machine senses a forward drag that the single face web, operating at corrugator speed, exerts on the glue applicator roll, driven at an underspeed, after bringing the flute tips of the single face web into contact with the glue applicator roll by adjusting the position of the rider roll. Changes in forward drag exerted on the glue applicator roll are monitored and related directly to glue applicator roll drive current to provide a slight compression of the single face web between the rider roll and the glue applicator roll. Preferably, the glue applicator roll uses a regenerative drive and the target drive current command in a feedback control system to cause the gap to be adjusted to achieve the desired slight compression of the web flutes and to maintain the glue applicator roll under speed.

Abstract: The present invention provides a method for facilitating efficient order change in the dry end conversion of a corrugated paperboard web by looking ahead to as many as three orders scheduled to follow the running order and repositioning slit tools and score tools to unused positions in anticipation of the orders to follow. The method is particularly effective to preset the slit and score tools for an order that follows a short order that may have a running time as short as 20 seconds.

Abstract: Clutch pressure or servo motor torque profiling is applied to the powered capstan roll in a corrugator web splicer to control tension in the paper in the accelerating new paper roll to bring the new roll up to line speed more quickly and without causing web tear out.

Abstract: A block of a solid lubricant material, such as PTFE, is biased continuously or intermittently against the cutting edge of a rotary slitting blade for corrugated paperboard. The solid lubricant block prevents the build up of starch adhesive and biasing movement compensates for wear of the block and wear of the cutting blade edge.

Abstract: A method and apparatus for performing an order change in a corrugator uses a minimum slit head configuration with all slit heads carried on two sides of a single tool support structure. A single robot is operable on the support structure to independently reset the positions of slit heads during a running order to prepare for subsequent order change in a most efficient manner, utilizing order scheduling that eliminates order changes that cannot be formed with the minimum slit head configuration.

Abstract: An order transition in a corrugated is accomplished by creating an overlap of the slits made by the slitting tools associated with the expiring (running) and new orders. However, the slit tool associated with the innermost slit between the upper and lower level outs is maintained in slitting contact with the board to extend the slit line into further overlap with the slits made by the new order tools to create an order change region. A lateral cut is made to connect the innermost slit between the upper and lower level outs on the new order and the slit created by the tool delayed from withdrawal in the running order.

Abstract: An order transition in a corrugated is accomplished by creating an overlap of the slits made by the slitting tools associated with the expiring (running) and new orders. However, the slit tool associated with the innermost slit between the upper and lower level outs is maintained in slitting contact with the board to extend the slit line into further overlap with the slits made by the new order tools to create an order change region. A lateral cut is made to connect the innermost slit between the upper and lower level outs on the new order and the slit created by the tool delayed from withdrawal in the running order. Trim cut transitions are handled in the same manner.

Abstract: A self-valving vacuum distribution system for a belt-driven sheet conveyor utilizes the sheets to automatically open vacuum control valves sequentially in a downstream direction as the sheet is carried on the belts. The system also automatically adjusts for varying sheet widths to automatically apply vacuum holding force only to the belt conveyor area covered by the sheet.

Abstract: A shingling apparatus for sheets of paper or paperboard includes a pair of independently operable vacuum plenums in a gap between an in-feed conveyor and a reduced speed shingling conveyor. One of the vacuum plenums decelerates an incoming sheet to shingling conveyor speed while the second vacuum plenum captures and pulls down the tail of the sheet to allow the faster moving following sheet to override the tail. This dual vacuum action enhances sheet control, requires very little vertical displacement of the sheets at the vacuum plenums, and enhances the squareness of the shingle that is formed. The system may also include a downstream shingle separator including a translating connection that assists in pulling the necessary gap between downstream shingle portion being directed into a stacker and an upstream shingle portion that is accumulated until the downstream shingle portion is stacked and discharged.

Abstract: A soft contact roll is mounted immediately downstream of the generator roll in a single facer to press the freshly glued single face web against the surface of the heated fluted bonding roll with a light load uniformly distributed across the full width of the web. The contact roll helps spread the adhesive more quickly and uniformly.

Abstract: A system is provided for synchronizing the end of order cutoff for a plunge slit order change on a corrugator that minimizes scrap and cuts the end order sheets to a length and width such that jam-ups at order change are eliminated. The system detects a transverse edge discontinuity immediately prior to end of order cutoff and, in conjunction with a prior calculation comparing sheet lengths and order end positions between upper and lower webs, positions an upstream transverse partial web slit at an optimum order end position such that the entire web is ultimately cut on the partial sever at an optimum position for scrap minimization and scrap sheet size and shape.

Abstract: An apparatus for slitting a running paperboard web includes a thin high speed rotary slitting blade that is plunged through the moving web and into a slot between a pair of anvil rollers supporting the web on the opposite side. Because the slitting blade and the anvil rollers are vertically separated and pre-positioned before order change, an adjustment apparatus is provided to spread the anvil rollers axially apart to provide an open gap with a large target for blade edge when it is plunged through the web and into the slot. The anvil rollers are then closed against the opposite faces of the blade for running operation. Preferably, the anvil rollers are mounted on brackets hinged together below the rollers to move the opposite upper edges of the rollers between the opened and closed position in the manner of a clam shell. The anvil roller assembly is also adjustable in the machine direction to compensate for reduction in rotary slitting blade diameter with blade wear.

Abstract: An apparatus for slitting a running paperboard web includes a thin high speed rotary slitting blade that is plunged through the moving web and into a slot between a pair of anvil surfaces supporting the web on the opposite side. Because the slitting blade and the anvil surfaces are vertically separated and pre-positioned before order change, an adjustment apparatus is provided to spread the anvil surfaces apart to provide an open gap with a large target for blade edge when it is plunged through the web and into the slot. The anvil surfaces are then closed to bring the edges of the surfaces against the opposite faces of the blade for running operation. Preferably, the anvil surfaces are mounted on brackets hinged together below the surfaces to move the edges of the surfaces defining the slot between the opened and closed positions in the manner of a clam shell.

Abstract: A corrugator single facer of the type utilizing a large diameter bonding roll and a small diameter corrugating roll provides quick roll change capability by mounting three large diameter bonding rolls on a rotatable turret and carrying corresponding small diameter corrugating rolls in a magazine positioned laterally offset from the machine. By driving the corrugating rolls indirectly through the pressure belt arrangement which supports the lower corrugating roll, roll change is significantly simplified.

Abstract: A single facer for corrugated paperboard of the type using a very large diameter fluted bonding roll and a much smaller diameter fluted corrugating roll which engages the bonding roll to provide a corrugating nip. The small diameter corrugating roll is made to be resilient so that it is capable of inward deflection in the vicinity of the corrugating nip in order to cushion impact as the rolls interengage along the corrugating nip. This cushioning deflection absorbs vibrational movement due to chordal action of the interengaging flutes, and thereby reduces noise levels, roll wear and improves the quality and consistency of corrugation.

Abstract: A running web is decurled by controlling web tension as well as the angle of wrap on a decurler roll and a cooperating pivot roll, all without affecting web tension in the downstream web converting process. An upstream brake roll and a downstream pull roll control web tension within the decurler apparatus and independent decurler rolls are provided for removing up-curl and down-curl.

Abstract: A single facer for corrugated paperboard of the type using a very large diameter fluted bonding roll and a much smaller diameter fluted corrugating roll which engages the bonding roll to provide a corrugating nip. The small diameter corrugating roll is made to be resilient by utilizing a thin walled roll shell so that it is capable of inward deflection in the corrugating nip in order to cushion impact and absorb the deflection as the rolls interengage along the nip. This cushioning deflection absorbs vibrational movement due to chordal action of the interengaging flutes, and thereby reduces noise level and roll wear and improves the quality and consistency of corrugation. A modified flute profile, compensating for flute pitch variations between the large diameter bonding roll and small diameter corrugating roll, assures uniform flute-to-flute engagement in the corrugating nip.

Abstract: A glue machine for a corrugator single facer utilizes a system of simultaneously operated linear actuators to move the glue machine from an idle position adjacent the single facer to a locked position on the single facer, and then to a running position with the glue machine glue roll in a pre-established position with respect to a corrugating roll on the single facer. The glue machine is carried on laterally spaced pairs of front wheels and rear wheels mounted on pivot arms. The linear actuators are preferably air cylinders interconnecting front and rear wheel pivot arms to provide sequential glue machine frame movement from the idle to the locked position, followed by movement to the running position.

Abstract: A rotary knife incorporates the use of an electronically controlled, active damping system to control vibrations of knife cylinders. The system preferably uses pairs of electromagnetic actuators to provide opposing pulling forces on a ferromagnetic portion of a lever arm that is mechanically coupled to the stationary support shaft for the knife cylinder. Vibration sensors, preferably accelerometers, are used to monitor vibrations of the respective knife cylinders. A digital signal processor implementing a state space control system controls the electromagnetic actuators to actively cancel vibration energy in the knife cylinders.