Abstract: A paperboard blank processing apparatus including a rotatably mounted processing head for operating upon successive paperboard blanks is disclosed. A paperboard blank registration sensor is provided upstream from the processing head for detecting a preprinted registration mark on a surface of an approaching paperboard blank. A controller is responsive to the registration sensor for determining whether the approaching paperboard blank is in proper registration with the rotary processing head. A registration correction window is defined by the controller and includes upper and lower limits defining upper and lower maximum correction values for bringing the angular position of the processing head into proper register with the linear position of the approaching paperboard blank. The controller further defines an averaging window containing the registration correction window wherein the registration correction window may be shifted within the averaging window in response to consistent registration errors.

Abstract: A method of working paperboard blanks is disclosed. The method includes providing first and second pairs of parallel rotary shafts supporting first and second pairs of tool heads respectively. The first pair of tool heads is moved to a predetermined longitudinal position along the first pair of shafts to define a first line of working. Likewise, the second pair of tool heads is moved to a predetermined longitudinal position along the second pair of shafts to define a second line of working wherein a center of the first line of working is displaced relative to a center of the second line of working. The paperboard blank is conveyed between the first and second pairs of tool heads to form a panel line on the paperboard blank. The tool heads may be automatically positioned along their respective shafts by coupling members which move linearly parallel to the shafts.

Abstract: A tool positioning device for use in combination with a machine for working paperboard blanks conveyed in a horizontal direction through the machine. The machine includes pairs of parallel rotary shafts wherein each pair of shafts includes upper and lower shafts and carry a plurality of tool heads. The positioning device includes a plurality of coupling members actuated in a vertical direction by actuators wherein the coupling members are moved downwardly into engagement with the tool heads. The coupling members are supported on an actuator support which is mounted to a transfer structure wherein the transfer structure moves the actuator support in axial movement to thereby slide the tool heads along their respective shafts to preselected positions along the shafts.

Abstract: An improved bundle former for corrugated paperboard boxes in which the timing of the lift mechanisms and the squaring plates is completely independent of the timing of the flexo-folder-gluer. Also, the stacking belt drive roll is mounted near the pull roll so its top periphery is below the path of box travel. This permits the folded box to contact the stacking belt tangentially, thereby easing the box's entry into the stacking station and providing an assist in squaring the box in the stack. The improved bundle former also includes simpler and more easily maintained elements.