EP-4741149-A2 - DUNNAGE CONVERSION MACHINE AND METHOD

EP4741149A2EP 4741149 A2EP4741149 A2EP 4741149A2EP-4741149-A2

Abstract

A cushioning conversion machine converts a sheet stock material into a relatively lower-density cushioning dunnage product. An exemplary sheet stock material includes two sheets that each overlap a common side of another sheet and are connected to respective lateral edges of the other sheet. The conversion machine includes a forming assembly having a former for shaping and randomly crumpling the sheet material, a set of adjustable guide members to guide the crumpled sheet material to a feeding assembly downstream of the forming assembly, and a severing assembly downstream of the feeding assembly that separates discrete lengths of cushioning. The severing assembly includes a window frame passage that guides the crumpled sheet material to an outlet during operation of the feeding assembly and constrains the crumpled sheet stock material during operation of the severing assembly.

Inventors

CHEICH, ROBERT C.
WAGNER, DENNIS J.
LEMMENS, Peter L.C.
PLUIJMEN, Rob A.H.

Assignees

Ranpak Corp.

Dates

Publication Date: 20260513
Application Date: 20200212

Claims (11)

A cushioning conversion machine, comprising a conversion assembly having a forming assembly for shaping a sheet stock material into a relatively lower density strip of dunnage, a feeding assembly downstream of the forming assembly, the feeding assembly having at least one rotating element to draw the strip of dunnage through the forming assembly, and a set of guide walls between the forming assembly and the feeding assembly to guide the strip of dunnage along a path from the forming assembly to the feeding assembly; where the set of guide walls includes at least one adjustable guide wall that is pivotally mounted at an upstream end adjacent the forming assembly and selectively positionable in any of a plurality of predetermined positions to vary at least one dimension of the path between the forming assembly and the feeding assembly.
A dunnage conversion machine as set forth in claim 1 or any claim depending from claim 1, where the set of guide walls include a guide plate with a plurality of circumferentially-spaced apertures and a pair of laterally-spaced adjustable guide walls having tabs that are receivable in corresponding apertures.
A dunnage conversion machine as set forth in claim 1 or any claim depending from claim 1, where the guide plate extends from the forming assembly and through the feeding assembly.
A dunnage conversion machine as set forth in claim 1 or any claim depending from claim 1, where the adjustable guide walls are curved to provide a convex surface that faces the path.
A dunnage conversion machine as set forth in claim 1 or any claim depending from claim 1, where the set of guide walls circumferentially bound the path.
A dunnage conversion machine, comprising a conversion assembly for converting a sheet stock material into a relatively lower density dunnage product that includes a feeding assembly having at least one rotating element to advance the sheet stock material along a path through the conversion assembly, and a severing assembly downstream of the feeding assembly to sever discrete lengths of dunnage products from the sheet stock material, the severing assembly including a stationary cutting blade and a driven cutting blade that is moveable relative to the stationary cutting blade across the path of the sheet stock material to sever discrete dunnage products from the sheet stock material; wherein the severing assembly further including a translating frame movable with the driven cutting blade between a feeding position and a severing position removed from the feeding position, the translating frame including a passage that is aligned with the path of the sheet stock material in the feeding position and blocks the path of the sheet stock material in the severing position, and the translating frame includes a crossbar that defines a side of the passage and redirects the sheet stock material to the path as the frame moves from the severing position to the feeding position.
A dunnage conversion machine as set forth in claim 6 or any other claim depending from claim 6, where the translating frame translates its position without rotating as it moves from the feeding position to the severing position.
A dunnage conversion machine as set forth in claim 6 or any other claim depending from claim 6, where the severing assembly includes a guide member to which the translating frame is mounted to guide the translating movement of the translating frame between the feeding position and the severing position.
A dunnage conversion machine as set forth in claim 6 or any other claim depending from claim 6, where the driven cutting blade is mounted to the translating frame adjacent the passage.
A pre-prepared sheet stock material for use in a dunnage conversion machine, comprising: a first sheet; and a pair of second sheets connected to lateral edges of the first sheet with an adhesive.
A pre-prepared sheet stock material as set forth in claim 10, where the pre-prepared sheet stock material has two coextensive plies, with a first ply received within a second ply, and where each ply has a first sheet and a pair of second sheets connected to lateral edges of the first sheet with an adhesive as set forth in claim 24.

Description

Field of the Invention This invention relates generally to a dunnage conversion machine that converts a sheet stock material into a cushioning dunnage product useful for packaging. Background In the process of shipping an item from one location to another, a protective packaging material is typically placed in the shipping case, or box, to fill any voids or to cushion the item during the shipping process. Some conventional protective packaging materials are plastic foam peanuts and plastic bubble pack. Paper protective packaging material is a very popular alternative to conventional plastic packaging materials. Paper is biodegradable, recyclable and made from a renewable resource, making it an environmentally responsible choice for conscientious industries. While paper in sheet form could be used as a protective packaging material, packaging companies usually prefer to convert the sheets of paper into a relatively lower density dunnage product to provide improved protection. This conversion may be accomplished by a dunnage conversion machine, such as those disclosed in commonly assigned U.S. Patent Nos. 5,123,889 and 5,322,477. Dunnage conversion machines typically convert a sheet stock material, such as paper, into a strip of dunnage having a lower density than the original stock material. Dunnage products of a desired length are severed or cut from the strip for use in packaging applications. Summary The present invention provides a cushioning conversion machine and method for converting a sheet stock material into a relatively less dense dunnage product having improved cushioning properties, and more particularly, into a cushioning product formed from stock material having its lateral regions inwardly turned and connected along a narrow central band, leaving an increased amount of stock material in randomly-crumpled lateral pillow portions, and providing improved cushioning properties in the pillow portions. To that end, the present invention provides a cushioning dunnage conversion machine converts a sheet stock material into a relatively lower-density cushioning product, where the sheet stock material includes two sheets that overlap and are connected to lateral edges of another sheet. The conversion machine includes a forming assembly having a former for shaping and randomly crumpling the sheet material, adjustable guide members to guide the crumpled sheet material to a feeding assembly downstream of the forming assembly with a controlled maximum dimension, and a severing assembly downstream of the feeding assembly that separates discrete lengths of cushioning. The severing assembly includes a window frame that guides the crumpled sheet material to an outlet during operation of the feeding assembly and constrains the crumpled sheet stock material during operation of the severing assembly. More particularly, the present invention provides a forming assembly for a cushioning conversion machine that includes an internal forming device. The internal forming device has a height dimension, a width dimension perpendicular to the height dimension, and a length dimension perpendicular to both the height dimension and the width dimension. The internal forming device further includes a bottom surface, and a pair of laterally-spaced lengthwise-extending protrusions that protrude from a common side of the bottom surface. The width dimension of the internal forming device decreases from an upstream end to a downstream end spaced from the upstream end along the length dimension, and the height dimension of the protrusions increases from the upstream end to the downstream end such that the protrusions include wedge-shape volumes. These wedge-shape volumes of the protrusions extend along converging axes, but the protrusions also include a pair of laterally-spaced lengthwise-extending parallel ridges, which also may be referred to as shoulders, that protrude above the wedge-shape volumes and are spaced inwardly from laterally-outer edges of the wedge-shape volumes. The internal forming device may have a uniformly-thick central region between the laterally-spaced protrusions. This central region may include a flat upper surface between the laterally-spaced protrusions. The bottom surface of the internal forming device may be flat or planar. The parallel ridges may extend from the upstream end a distance less than the length dimension. The resulting internal forming device may include a step change in a height of an upper surface of the laterally-spaced protrusions laterally outwardly positioned relative to the parallel ridges. The protrusions may further include laterally outer cavities extending laterally inwardly from laterally outer extents of the wedge-shape volumes, and the protrusions may have circular cross-sections at the downstream end of the internal forming device. In one or more embodiments, the internal forming device may be symmetric about a lengthwise-extending vertical plane, and each of the laterally-sp