US 5,090,281 A · Slitting apparatus for corrugated paperboard and the like

Abstract

An apparatus for providing longitudinal, laterally spaced slits in a continuously moving sheet or web of corrugated paperboard or the like includes a plurality of upper tool heads each supporting a thin, circular rotary slitting blade. The blades are coaxially mounted and driven by a common drive shaft and each blade-carrying tool head is independently positionable across the width of the paperboard sheet. Each slitting assembly includes a lower tool head or counterhead carrying a roller assembly which supports the underside of the moving board and provides a firm surface to support the board against the upper rotary slitting blade. The roller assembly includes a circumferential radially extending slot in its outer surface through which an edge portion of the upper cutting blade travels with the sheet firmly supported by the roller surfaces on each side of the slot. A blade lubricator is attached to the upper head and applies a thin film of lubricant to the blade edge by direct engagement by a lubricating wick while the blade is rotating. The thin blade is maintained in a sharpened condition by periodic engagement with a rotary sharpening tool pivotally attached to the upper tool head for periodic light sharpening contact with one face of the beveled blade cutting edge.

Claims14

Dependent claims

An apparatus for longitudinally slitting a moving sheet of corrugated paperboard of the type having multiple paper layers secured together with a starch-based adhesive, said apparatus comprising:

a tool head mounted on one side of the sheet and translatable laterally across the width of the sheet on a line parallel thereto;
an annular blade rotatably attached to said tool head said blade having a smooth continuous peripheral cutting edge defined by similar beveled edge faces on opposite sides of the cutting edge, and said cutting edge extending beyond the opposite side of the sheet;
a counterhead mounted on the opposite side of the sheet and translatable laterally across the width of the sheet on a line parallel to the line of translation of said tool head;
idler roller means rotatably attached to said counterhead and having a cylindrical outer surface positioned to make tangent contact with said opposite side of the sheet;
an annular circumferential slot in the outer surface of said roller means, said slot having a width greater than the maximum width of the peripheral edge of said blade defined by said edge faces and positioned to receive without contact said blade edge and edge faces therein to form a nip;
means for rotating said blade to move the peripheral edge thereof in the direction of movement of the sheet and at a speed at least about two times greater than the speed of the sheet;
direct contact means for applying a lubricant to the peripheral edge of said blade for preventing the adherence and build-up of starch thereon;
and,
means for sharpening the cutting edge of the blade while said blade is rotating.

6 more elements

An apparatus for longitudinally slitting a continuous, traveling sheet of corrugated paperboard made of multiple layers of paper glued together with a starch-based adhesive to provide a plurality of parallel spaced slits, said apparatus comprising:

an upper support structure overlying the sheet and having upper guide means defining an upper linear path across the width of the sheet;
a plurality of upper tool heads mounted on said upper guide means, each of said upper tool heads movable individually thereon along said upper linear path;
a tool holder rotatably attached to each upper tool head for rotation on a common axis parallel to said guide means;
a drive shaft positioned on said common axis to simultaneously drive said tool holders and to support said tool holders and upper tool heads for movement along said upper guide means;
a thin annular blade carried on each tool holder, each of said blades presenting a downwardly depending continuous circular cutting edge defined by smooth beveled edge faces on opposite sides of said edge, which edge and side faces extend below the bottom side of the sheet;
a lower support structure under the sheet and having lower guide means defining a lower linear path parallel to the upper linear path;
a plurality of lower tool heads mounted on said lower guide means, each of said lower tool heads movable individually thereon along said lower linear path;
idler roller means rotatably attached to each of said lower tool heads, each roller means having a cylindrical outer surface positioned to make tangent contact with the bottom side of the sheet;
an annular circumferential slot in the outer surface of said roller means, said slot having a width greater than the maximum width of the edge faces defining said blade edge and positioned to receive therein without contact the blade cutting edge and edge faces extending below the sheet;
means for rotating said drive shaft to move said blade cutting edges at a speed at least about two times greater than the speed of the moving sheet;
direct contact means for applying a lubricant to said blade cutting edges to prevent the adherence and build-up of starch thereon;
and,
means for sharpening the blade cutting edges while said blades are operating.

10 more elements

Dependencies are inferred from the claim text.

Slitting apparatus for corrugated paperboard and the like

Life of this patent

Slitting apparatus for corrugated paperboard and the like

Life of this patent

Abstract

Claims14