The present invention relates to machines for converting sheet stock material into a dunnage packaging product and, more particularly, to a method and supply of two-ply stock material supply that facilitates splicing a new or succeeding supply of stock material to an almost-spent supply of stock material.
Dunnage conversion machines convert sheet stock material from a supply thereof into a relatively less dense dunnage product useful in packaging to protect articles during shipment. The sheet stock material usually is supplied in the form of a roll or a fan-folded stack, from which the sheet stock material is payed off for conversion by the machine into the dunnage product.
When the supply is spent, a new supply is loaded in place of the spent supply and the leading end of the new supply is inserted into the machine. Because it can be difficult to get the new supply to feed properly, operators have learned to stop the machine before the trailing end of the sheet material enters the machine, and to splice the leading end of the new supply to the trailing end of the almost-spent supply. When the machine is operated once again, the trailing end of the almost spent supply will pull the leading end of the new supply into and through the machine.
Common splicing techniques include using one or more strips of tape to attach a leading end of the succeeding supply of stock material to a trailing end of the almost-spent supply of stock material, and spraying a liquid adhesive on the trailing end of the almost spent supply and then pressing the leading end of the succeeding supply to the adhesive-covered trailing end.
Another technique is to pre-apply a double-sided adhesive to the leading or trailing ends of the supply, with a removable covering that the operator can remove before splicing the leading end of the succeeding supply of stock material to the trailing end of the almost spent supply of stock material. This latter technique is described in commonly-owned U.S. Pat. No. 6,756,096, which is hereby incorporated herein by reference. When this technique is used with a multi-ply sheet stock material, an adhesive strip must be applied to each ply, and each ply must be attached to a corresponding ply in a particular sequence. For example, the removable covering is removed from the adhesive on a first ply, and the leading ends and trailing ends of the corresponding plies furtherest from the operator are attached together. Then the removable covering is removed from the adhesive on a second ply, and the next-nearest (relative to the operator) corresponding plies are attached together. This process is repeated until all of the plies are spliced.
The present invention provides an improved splicing method, particularly for two-ply sheet stock material, and an improved supply of two-ply sheet stock material, both of which simplify the process of splicing a succeeding or new supply of two-ply stock material to an almost-spent supply of two-ply stock material.
According to the present invention, a supply of sheet stock material includes two plies of sheet stock material rolled or folded into a compact configuration, such as a roll of wound material or a stack of fan-folded material. The leading ends of the plies of the new supply are temporarily secured together, and an adhesive is pre-applied to each of the outwardly-facing opposing surfaces of respective plies if on the leading end of the new supply, or to each of the inwardly-facing opposing surfaces of respective plies if on the trailing end. A removable covering or release liner typically covers the adhesive until ready for splicing. In use, the release liner is removed and the leading ends of the plies of the new supply, which are temporarily attached to one another, are placed between the trailing ends of the respective plies of the almost-spent supply, and the plies are readily secured by pressing the overlapping plies together, without any sequencing limitation. In other words, no extra care is required to ensure that the correct plies of the respective supplies are being attached together in the correct sequence, as was required in prior methods and supplies of sheet stock material. The leading ends of the plies of the new supply may remain connected together until drawn through the conversion machine, which may separate the plies or allow the plies to remain connected.
More particularly, and generally paraphrasing the original claims, the present invention provides a supply of sheet stock material suitable for use in a dunnage conversion machine that includes a first ply of sheet stock material and a second ply of sheet stock material that overlaps the first ply. The first ply and the second ply both have an adhesive layer adjacent one of a leading end or a trailing end of each ply. The adhesive layer is applied to opposing outwardly-facing surfaces of the respective plies if adjacent the leading ends and the adhesive layer is applied to respective inwardly-facing surfaces of the respective plies if adjacent the trailing ends.
The first ply and the second ply may be attached to one another adjacent their respective leading ends. For example, the first ply and the second ply may be secured together with an adhesive between inwardly-facing surfaces of the plies.
The first and second plies may be rolled or folded into a compact configuration. For example, the first and second plies may be rolled around a common core to form a roll of two-ply sheet stock material. Alternatively, the first and second plies may be fan-folded to form a stack of two-ply sheet stock material.
The first ply and the second ply may include paper. The first and second plies may have substantially the same width dimension. The leading end of the first ply may be aligned with the leading end of the second ply.
The adhesive layer may be disposed on a carrier and may be covered by a removable release liner. The adhesive layer may be adjacent a leading end of each ply. The adhesive layer may include a pressure sensitive adhesive and a removable release liner covering the pressure sensitive adhesive.
The adhesive layer may be applied across substantially the full width of at least one ply. The adhesive layer may have a substantially continuous length. The adhesive layer may have a major dimension that extends parallel to a width dimension of the overlapping plies. The adhesive layer on the first ply may be aligned with the adhesive layer on the second ply.
The present invention also provides a method of converting a two-ply sheet stock material into a relatively lower density dunnage product. The method includes the following steps: (a) operating a dunnage conversion machine to produce one or more dunnage products from a supply of sheet stock material having a first ply and a second ply until the supply of sheet stock material is almost spent, the supply being a preceding supply, (b) displacing a trailing end of the second ply of the preceding supply of sheet stock material to expose a trailing end of the first ply of the preceding supply of sheet stock material, (c) providing a succeeding supply of two-ply sheet stock material having a first ply and a second ply that overlaps the first ply, (d) attaching a leading end of the first ply of the succeeding supply of sheet stock material to the first ply of the preceding supply of sheet stock material, (e) replacing the trailing end of the second ply of the preceding supply of sheet stock material over the leading end of the second ply of the succeeding supply of sheet stock material to secure the second ply of the succeeding supply of sheet stock material to the second ply of the preceding supply of sheet stock material, and (f) operating the dunnage conversion machine once again to produce one or more dunnage products from the succeeding supply of sheet stock material.
The attaching step may include removing a release liner covering a pressure sensitive adhesive layer and applying pressure to the sheet stock material adjacent the adhesive layer.
The method may further include the step of connecting the leading ends of the first ply and the second ply of the succeeding supply of sheet stock material before the attaching step.
The foregoing and other features of the invention are hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail plural illustrative embodiments of the invention, such being indicative, however, of but a few of the various ways in which the principles of the invention may be employed.
Referring now to the drawings in detail and initially to
In
The supply of stock material 34 generally is provided in a compact configuration, such as a roll of stock material 44 (
The supplies 34 and 43 of sheet stock material 32 shown in
The supplies 34 and 43 of sheet stock material 32 also include a pre-applied layer of adhesive 42 adjacent either a leading end 40 or a trailing end 46 of each ply P1 and P2 to attach the leading ends 40 of each ply P1 and P2 of the new supply of stock material 34 or 43 to the trailing ends 46 of respective plies P1 and P2 of the almost-spent supply of stock material 45. Alternatively, an adhesive layer 42 may be applied near a leading end 40 of one ply P1 or P2, and near a trailing end 46 of the other ply P2 or P1. Further, the adhesive layers 42 on respective plies P1 and P2 may be longitudinally aligned, as shown in
The adhesive layer 42 typically is covered with a removable cover 70, sometimes referred to as a release liner, to protect the adhesive layer 42 until it is needed. An exemplary adhesive is a pressure-sensitive adhesive. The adhesive layer 42 and release liner 70 extend transversely across the width of the ply P1 and P2. By removing the release liner 70, such as by manually peeling same from the adhesive layer 42, the leading end 40 of the stock material 32 may be spliced to, or more particularly adhered to, a corresponding surface of a trailing end 46 of an almost-spent supply of stock material 45 extending from the upstream end 52 of the machine 30 of
The adhesive layer 42 also may be provided as a double-sided tape that is secured to the stock material 32. As another alternative, a cohesive may be applied to both the outwardly facing surfaces of the plies P1 and P2 adjacent their leading ends 40 and to inwardly-facing surfaces adjacent their trailing ends 46. A cohesive is like an adhesive but only sticks to other cohesive or cohesive-coated surfaces. Consequently only one of the inwardly-facing surfaces would require a removable release liner. When the cohesive is applied to the outwardly-facing surfaces, the layer of sheet stock material underlying or adjacent the adhesive layer 42 may serve as the release liner, enabling the clean and easy removal of the adhesive layer 42 therefrom.
The adhesive layer 42 may include a reduced strength adhesive, meaning a pressure sensitive adhesive that enables a release liner 70 to be cleanly and easily removed from the adhesive layer 42 to expose the adhesive layer, which exposed adhesive layer 42 may be removably adhered to the sheet stock material 32. This permits the sheet stock material 32 to be wound, or stacked, on top of itself, i.e., to contact the underlying adjacent layer of sheet stock material 32. In addition, this permits the sheet stock material 32 to be repositioned when splicing. The reduced strength adhesive provides sufficient adhesive holding power and shear strength between the spliced plies P1 or P2 to hold the leading end 40 and the trailing end 46 together when subjected to a longitudinal pulling force. An exemplary adhesive is the adhesive used for Highland™ brand removable notes manufactured by the 3M Company of St. Paul, Minn., U.S.
With a reduced strength adhesive, the leading end 40 of a ply P1 or P2 of sheet material 32 may be repositioned, as desired, to obtain the appropriate alignment between the leading end 40 of the ply P1 of sheet material 32 of the succeeding supply of stock material with the trailing end 46 of the ply P1 of the almost-spent supply of stock material. The adhesive layer 42 has sufficient shear strength and adhesive holding power to maintain the splice (i.e., the adhesive bond) of the leading end 40 of the succeeding supply of stock material 34 to the trailing end 46 of the almost-spent supply of stock material when the stock material 32 is advanced through the conversion machine 30.
Alternatively, the adhesive layer 42 may include an adhesive having a holding power and shear strength that provides a permanent bond (i.e., not removable) between the plies of sheet stock material when spliced. In this case, the adjacent layer of sheet stock material, or at least the portion of the adjacent layer of stock material which the adhesive layer 42 overlaps, will require a surface treatment such as by application of a coating of a material which would enable clean and easy removal of the adhesive layer 42 from the overlapped portion; in other words, to enable the overlapped portion to operate as the release liner.
To splice the leading end 40 of a new supply of stock material 34 or 43 to the trailing end 46 of an almost-spent supply of stock material 45, the leading end 40 of the sheet material 32, is removed (i.e., unwound or unfolded) from the new supply of stock material 34 or 43 and the outwardly-facing surfaces of the respective plies P1 and P2 are spliced to, or more particularly adhered to, the inwardly-facing surfaces of the trailing ends 46 of the respective plies P1 and P2 of the almost-spent supply of stock material 45.
A method of employing the stock material 32 provided by the invention is illustrated in
An alternative method is shown in
Because the plies P1 and P2 typically travel slightly different paths through the conversion machine 30 (
In
Similarly, one or more pairs of spaced-apart cuts may be made through both plies P1 and P2 at either a side near a leading end 40 (
Another alternative is shown in
The plies P1 and P2 also can be connected together by layers of tape 94 applied on both sides of the opening 100, to the outwardly-facing surfaces of both plies P1 and P2, with the adhesive tape 94 on one ply P1 secured to the adhesive tape 94 on the other ply P2 through the opening 100. This arrangement can be used in addition to tabs 98, such as in
An exemplary dunnage conversion machine 110 is shown in
The illustrated conversion assembly 112 includes a former or forming assembly 126 and a feeding/connecting assembly 128 powered (energized) by a feed motor 130, for example an electric motor, through a motion transfer assembly 132. Downstream of the feeding/connecting assembly, a severing assembly 134 (for example a cutting assembly) powered by suitable means, such as the illustrated motor and motion transfer assembly 136 is provided to separate lengths or sections of dunnage products from the generally continuous strip of dunnage produced by the feeding/connecting assembly 128. The forming assembly 126, the feeding/connecting assembly 128, and the severing assembly 134 are mounted to or in a housing 138 in a well-known manner. The operation of the conversion machine 110 may be controlled by a controller, also in a well-known manner. As will be apparent, other types of conversion assemblies may be employed to convert the sheet material to a strip of dunnage, and other types of severing assemblies may be employed to separate discrete sections of dunnage products from the strip of dunnage produced by the conversion assemblies.
The illustrated forming assembly 126 includes a forming member 144, such as a forming frame, and a converging shaping chute 146. The forming assembly 126 randomly crumples the sheet stock material and causes an inward rolling or folding of the lateral edges of the sheet stock material to form a continuous strip of cushioning having lateral pillow-like portions. The shaping chute 146 includes longitudinally extending, transversely converging side walls 150 which preferably are curved or arcuate in transverse cross-section. As the sheet stock material passes through the shaping chute 146, the side edges turn or roll inwardly towards one another so that the inwardly turned or rolled edges form resilient pillow-like crumpled portions of stock material disposed in lateral abutting relationship as they emerge from the exit end of the shaping chute.
The forming member 144 coacts with the shaping chute 146 to randomly crumple the stock material, while also shaping and forming the stock material, including guiding a central portion of the stock material along the bottom wall 154 of the shaping chute 146 for controlled inward rolling or folding of the side edge portions of the stock material.
The illustrated feeding/connecting assembly 128 includes a pair of cooperating and opposed gears or gear-like members 160 and 162. The gears 160 and 162 of the feeding/connecting assembly 128 perform two functions in the operation of the machine 110. One function is a “feeding” function, with the gears pulling the stock material from the supply of stock material and then through the forming assembly 126. The stock material is then discharged by the feeding/connecting assembly 128 to the severing assembly 134. The second function that may be performed by the feeding/connecting assembly 128 is a connecting function. Specifically, the feeding/connecting assembly 128 connects overlapping layers of stock material along a central band, passing between the two opposing gears 160 and 162 to form a connected strip. Other mechanisms may be employed to “connect” the strip, i.e., to operate on the strip in such a manner that it will retain its shape as opposed to reverting to the original flat form of the stock material. Known connecting mechanisms include mechanisms that crease the stock material to enable the stock material to hold its three-dimensional shape, and mechanisms that “punch” tabs through overlapping layers to hold those layers together.
The connected strip travels downstream from the feeding/connecting assembly 128 to the severing assembly 134 which severs, for example by cutting, the strip into a section of a desired length.
Referring now to the upstream end 114 of the conversion machine 110, the stock material is supplied to the conversion machine 110 from a stock supply assembly 166. The illustrated stock supply assembly includes a pair of C-shape laterally spaced apart mounting brackets 170 secured to the conversion assembly 112. When rolled stock material is used with the conversion machine 110, the lower legs of the brackets 170 have journaled between the ends thereof a stock supply roll 172. When fan-folded stock material (
As described above, when the trailing ends of the plies of an almost spent supply of stock material are held, the leading ends of the plies of a succeeding supply of stock material may be spliced to the trailing ends. To detect that a supply of stock material is nearing its depleted or spent state, an end of web detector may be included upstream of the conversion assembly to detect the trailing end of one or more plies before the trailing ends of the stock material are pulled into the conversion machine.
In summary, in
Thus, the present invention provides a supply of stock material 34 and 43 for a dunnage conversion machine 30 that includes two plies P1 and P2 of sheet stock material 32 wound into a roll 44 or fan-folded into a stack 56 (
Although the invention has been shown and described with respect to certain embodiments, equivalent alterations and modifications will occur to others skilled in the art upon reading and understanding this specification and the annexed drawings. In particular regard to the various functions performed by the above described integers (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such integers are intended to correspond, unless otherwise indicated, to any integer which performs the specified function of the described integer (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.
Number | Date | Country | |
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62161563 | May 2015 | US |
Number | Date | Country | |
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Parent | 15574023 | Nov 2017 | US |
Child | 17104141 | US |