The invention relates to the winding of web materials about winding cores to form rolls of the materials, and the subsequent unwinding of the web materials from the rolls and splicing of a web tail end of a depleted roll to the web leading end of a new roll.
Web materials such as polymer film, paper, nonwoven or woven textile, metal foil, sheet metal, and others, are used in the manufacture of a variety of products. The web materials generally are provided in the form of large rolls formed by winding the web material about a winding core. To begin the winding process, a tail end of a web is attached to the winding core and the core is rotated about its axis to wind the web into a roll.
To manufacture products, the web material is unwound from the roll and subjected to converting operations, the particulars of which vary depending on the products being made. When the web from one roll is fully unwound, a splicing operation is performed wherein the leading end of the web from a new, full roll is attached to the tail end of the just-depleted roll, so that web material may be continuously supplied to the converting machinery.
Various approaches to the splicing of web material have been used, but the operation generally entails the use of some type of adhesive tape or substance for attaching the tail and leading ends of the webs together. If the adhesive were present on the tail end of a web prior to winding, the adhesive generally would have to face away from the core because that is the side of the web that will be brought into contact with the leading end of the new web to form the splice. Accordingly, the adhesive would stick to the subsequent turn of the web when the web is wound into a roll, which is clearly undesirable. Thus, some provision for preventing such sticking is necessary. U.S. Pat. No. 5,855,714 to Bockh proposes to overcome this difficulty by providing a non-adherable region on the tail end of the web adjacent the adhesive. The non-adherable region is long enough to extend at least one full turn about the core so that the adhesive is contacted by the non-adherable region and thereby is prevented from sticking. It may not be convenient or practical to form a non-adherable region on some types of web material, and in any event it would require a separate operation on the web prior to winding.
Additionally, mechanisms for splicing web materials generally have not aided or performed any function associated with the winding of the web into a roll.
The present invention addresses the above needs and achieves other advantages, by providing a dual-functioning mechanism that aids in splicing of webs and that can also aid in the startup of the winding process. The mechanism in certain embodiments of the invention generally comprises two components that initially are attached to each other at the startup of winding, but that detach from each other at completion of unwinding so as to expose a previously unexposed adhesive region that can attach to the leading end of another web to accomplish a splice. The mechanism is connected between the tail end of a web and a winding core so as to affix the web to the core prior to winding the web into a roll about the core. The attachment of the web to the core provided by the mechanism is sufficiently strong to withstand the tension exerted on the web at the start of winding without the two components of the mechanism detaching from each other. At completion of unwinding, however, the tension exerted on the web tending to pull the two components apart serves to separate the components and thereby expose an adhesive region on the component that remains attached to the tail end of the web.
The mechanism generally comprises a core component for attachment to the core and a web component for attachment to the web. In some embodiments of the invention, the core component has a core-attaching portion structured and arranged to attach to the core and a free end portion joined to the core-attaching portion, the free end portion extending out from the core when the core-attaching portion is attached to the core. The web component has a tail portion structured and arranged to attach to a tail end of a web and a leading portion joined to the tail portion, the leading portion extending out from the tail end of the web when the tail portion is attached to the tail end. The leading portion has adhesive disposed thereon and is adhered to the core component with sufficient adhesive bonding strength to remain attached when winding tension is exerted between the core and the tail end of the web during startup of winding of the web onto the core to form a roll. However, the adhesive bonding strength is low enough to allow the leading portion of the web component to detach from the core component at completion of unwinding of the roll such that the adhesive on the leading portion extending from the tail end of the web is exposed for attachment to a leading end of another web being unwound from a new roll to splice the webs together.
The adhesive on the leading portion of the web component in one embodiment is substantially completely covered by the free end portion of the core component when the two components are joined together at startup of winding of the web. In this manner, the adhesive on the leading portion is prevented from sticking to a subsequent turn of the web during winding.
The web component conveniently can comprise a splicing tape. A portion of the length of the tape is affixed to the tail end of the web, and the remaining portion of the length extends beyond the tail end for attachment to the core component.
The core component can have various configurations and constructions. In one embodiment of the invention, the core component comprises a substrate (e.g., paper, plastic film, cloth, etc.) that includes a release material disposed on one side of the substrate over a portion of the substrate length. The remainder of the substrate length (or at least a part thereof) is attached to the core prior to winding of a web about the core. An adhesive can be applied to the core for the attachment of the substrate, or adhesive can be disposed on the substrate, or adhesive can be disposed on both the core and the substrate.
In accordance with another embodiment of the invention, the core component comprises a substrate having an upper surface and a lower surface, with a release material covering the upper surface. A portion of the length of the substrate is folded over such that part of the substrate comprises two layers and the rest comprises a single layer. The part having two layers forms the free end portion for attachment to the web component, and has the release material disposed on both of its opposite surfaces by virtue of the folded-over portion. The part having one layer forms the core-attaching portion that is attached to the core prior to winding. Advantageously, the folded-over portion of the substrate is free to unfold upon completion of unwinding when the tail end of the web is pulled away from the core. As the folded-over portion of the substrate is unfolded, it moves into a more-advantageous orientation relative to the web component attached to it for peeling the web component off the substrate.
The core-attaching portion of the core component can have a double-sided adhesive tape, or a layer of adhesive, disposed on its lower surface for attaching the core component to the core. The core-facing side of the adhesive tape, or the adhesive layer, can have a release liner attached to it to prevent sticking of the core component to various objects until it is desired to attach the core component to the core. The release liner can be peeled off to expose the adhesive tape or adhesive layer just prior to attaching the core component to the core.
Similarly, prior to attaching the web component to the tail end of the web, the portion of the web component that is not attached to the core component can have a release liner attached to the adhesive surface. The release liner can be peeled off to expose the adhesive surface just prior to attaching the web component to the web.
In another embodiment of the invention, the web component comprises a splicing tape having a tail portion attached to the tail end of the web and a leading portion that extends out from the tail end. The leading portion is folded beneath the tail portion so that the adhesive on the leading portion faces away from the tail portion. The leading portion is adhered to the release surface of the core component. The core component can comprise a substrate having one portion attached to the core and a free end portion that extends out from the core. Alternatively, the core component can comprise a layer of release material disposed on the core. Upon unwinding, the folded splicing tape unfolds and detaches from the core component, thereby exposing the adhesive on the leading portion of the splicing tape for splicing the tail end of the web to a leading end of another web.
Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
The present inventions now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
A dual-functioning mechanism for startup and splicing of a webs in accordance with a first embodiment of the invention, is depicted in
The core component 40 comprises a substrate 42 of suitable sheet material (e.g., paper, plastic film, cloth, etc.). A layer of adhesive 44 is disposed on one side of one lengthwise portion of the substrate. A release liner 46, which can comprise, for example, a silicone-coated paper or the like, covers the adhesive 44 and is adhered to the adhesive in releasable fashion. An end region 48 of the substrate, which is preferably free of adhesive, is folded beneath an adjoining region 50 of the substrate, which also is preferably free of adhesive. The folded end region 48 is adhered to the portion of the splicing tape 32 that is not covered by the release liner 38.
The surface of the folded end region 48 that is adhered to the splicing tape 32 preferably is such that it will readily peel off the splicing tape when the splicing tape is pulled away from the folded end region 48 in a direction out of the plane of the end region. To this end, the end region 48 can have a suitable release material (e.g., silicone, not shown) disposed thereon; alternatively, the material of the substrate 42 itself may be such that the splicing tape will readily peel off the end region. However, the adhesive bond between the splicing tape and the end region 48 preferably is sufficiently strong to resist detachment of the splicing tape when the splicing tape is pulled away from the end region in a direction lying in the plane of the end region, i.e., in a direction tending to place the adhesive interface in shear as opposed to peeling it apart.
As shown in
More particularly, the mechanism 20 is prepared for use by first peeling off the release liner 46 from the adhesive 44 on the substrate 42 of the core component 40. The portion of the substrate 42 having the thus-exposed adhesive 44, which is referred to herein as the core-attaching portion, is affixed to the outer surface of the core C via the adhesive 44. The remaining portion of the substrate 42 remains unaffixed to the core and is referred to herein as the free end portion, and comprises the folded end region 48 and the adjoining overlying portion 50. The folded end region 48 thus lies between the outer surface of the core and the overlying portion 50 of the substrate. The free end portion of the substrate is affixed to the portion of the splicing tape 32 that is not covered by the release liner 38, which is referred to herein as the leading portion of the splicing tape.
Next, the release liner 38 is peeled off the splicing tape 32 to expose the adhesive 36 on the remaining portion of the splicing tape, which is referred to herein as the tail portion of the splicing tape. The tail portion of the splicing tape is then adhered to the tail end 52 of the web W via the thus-exposed adhesive 36. The web is now ready to begin winding about the core.
By virtue of the construction and arrangement of the mechanism 20, it will be recognized that as the core is rotated to begin winding the web about the core, the tension force between the core and the tail end tends to place the adhesive bond between the web component 30 and the core component 40 in shear rather than peeling it apart, and the web component remains attached to the core component. The core component 40 resists unfolding because the folded end region 48 is trapped between the core and the overlying portion 50. Thus, the mechanism 20 is sufficiently strong to remain intact under the levels of tension exerted during the startup of the winding process.
However, at the completion of unwinding of the roll during a converting operation or the like, the web component 30 readily detaches from the core component 40 such that the web component remains attached to the tail end of the web and provides an exposed adhesive surface for splicing the tail end to another web, as further explained below with reference to
As depicted in
A fourth embodiment of a mechanism 120 in accordance with the invention is shown in
The core component 140 includes a substrate 142 of suitable material (e.g., paper, plastic film, cloth, etc.). One side of a first lengthwise portion of the substrate (referred to herein as the free end portion) is releasably adhered to the folded leading portion 132a of the splicing tape. On the opposite side of a second lengthwise portion of the substrate (referred to herein as the core-attaching portion) is a layer of adhesive 144; a release liner 146 covers the adhesive 144 and is removed just prior to affixing the core-attaching portion of the substrate 142 to a winding core. The free end portion of the substrate 142, to which the splicing tape 132 is adhered, remains unaffixed to the core. Before startup of winding of a web about the core, the release liner 136 is removed from the splicing tape and the tape is attached to the tail end of the web. The winding core is rotated to begin winding the web about the core.
During unwinding of the web from the roll, when the tail end of the web begins to be advanced away from the winding core, the splicing tape 132 peels off the substrate 142 and unfolds in the process. Once the splicing tape completely detaches from the substrate of the core component, the splicing tape assumes the configuration as shown in
A fifth embodiment of a mechanism 220 in accordance with the invention is shown in
The mechanism 320 includes a splice-detection element 333 incorporated into the splicing tape 332. As shown, the splice-detection element 333 is disposed on the surface of the splicing tape 332 opposite the surface that attaches to the web, and is located on the tail portion of the splicing tape; alternatively, the splice-detection element could be located on the other surface of the tape, or could be embedded or impregnated in the thickness of the tape, and/or could be located on the leading portion of the tape. The splice-detection element is detectable by a suitable sensor so that the location of the splice between webs can be automatically sensed. This is useful during a converting operation, for example, because products made from the portion of the web material containing the splice must be discarded; the ability to automatically detect the splice can enable automatic discarding of such defective products. The splice-detection element can be detected in various ways, including but not limited to optical detection or metal detection (e.g., induction imbalance, pulse induction, or beat frequency oscillation). Thus, the splice-detection element may have an optically detectable property (e.g., opacity, color, reflectivity, etc.). Alternatively, the splice-detection element may incorporate metal (e.g., metal foil, iron shavings, etc.).
Any of the other embodiments shown in
While a release material is shown in the embodiments of
Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.