Method for Adapting Separable Fasteners for Attachment to Other Objects

FIG. 1 is a simplified side view showing the type of end product with which the present invention is associated.

FIG. 2 is a simplified cutaway side view of a mold as wherein the preset application is applicable at the point in time when foam-producing liquid has been introduced therein.

FIG. 3 shows the mold of FIG. 2 after the liquid has been foamed.

FIG. 4 shows the product produced by the molding procedure of FIG. 2 and 3 in its ideal configuration following removal from the mold.

FIG. 5 is an enlarged view of the attachment strip portion of the article of FIG. 4 disclosing a problem common to the molding step which is eliminated by the present invention.

FIG. 6 is a drawing showing a prior art approach to adding a protective cover over the fastener strip prior to positioning it within the mold.

FIG. 7 shows the strip of FIG. 6 as positioned within a mold groove.

FIG. 8 is an enlarged view showing the manner in which the sides of the strip overlap the edges of the groove in the prior art leaving a gap through which liquid can enter to foul the fastening surface.

FIG. 9 shows a strip of fastener material according to the present invention in a first embodiment.

FIG. 10 is a detailed view of one side of the strip of FIG. 9 when disposed in the mold groove.

FIG. 11 shows a strip of fastener material according to the present invention in a second and preferred embodiment thereof.

FIG. 12 is a detailed view of one side of the strip of FIG. 11 showing the manner in which it forms a pair of gaskets along either side of the mold groove.

A first (although not preferred) embodiment of the present invention is shown in FIG. 9 and 10. This embodiment can be used where it is desired to cover the hooks 32 with a polyethylene sheet 56 because a post-molding process of sufficient temperature to remove the polyetheylene sheet is employed. Whereas in the prior art technique of FIGS. 6 and 7, the polyethylene sheet 56 was attached from the edge of the backing strip 36 at 64 inward and the metal strip 52 was positioned in the middle of the composite structure 34, as shown in FIGS. 9 and 10, in this embodiment, the polyethylene sheet 56 is attached to the backing strip 36 of the composite structure 34' by hot melt adhesive 66 in the region of the equal strips 54 from a point close adjacent the fastener strip 42 outward to a point intermediate (i.e. not reaching) the edge 64 of the backing strip 36. The backing strip carries a large plurality of loops (uncut hooks of a hook and loop fastener) to engage foam formed in the mold. It is actually preferred that the polyethylene sheet 56 extend beyond the outer edge 64 to provide extra material for forming the gasket which has been found to form. While the benefits of this construction with respect to forming a gasket can improve the molding where a centrally-located metal strip 52 as shown in FIG. 6 and 7 is employed, it is also possible that the magnet 60 (or a pair of magnets if smaller magnets are desired) be located close adjacent the inner edge of the equal strips 54 where they abut the outer edges of the fastener strip 42. For this purpose, it is preferred that the metal strip 52 be replaced by ferrous particulate matter embedded in hot-melt adhesive 66, or the like, used to attach the polyethylene sheet 56 to the backing strip 36. The use of such particulate material within the bonding material is not a point of novelty of the present invention and is, in fact, known in the prior art. The positioning of the adhesive with respect to the fastening of the polyethylene sheet 56 to the backing strip 36 is, however, a point of novelty of the pesent invention and the combination of the magnetic force being created at the same point is also considered to be novel. As shown in FIG. 10, should any arching of the backing strip 36 take place, the unattached outer edge 63 deforms as a result of the heat of molding and the pressure of the foam-forming liquid 24 thereon to form a gasket between the backing strip 36 and the upper outer edge 58 of the mold 18 adjacent the groove 20 as shown in FIG. 10.

The preferred embodiment of the present invention is shown in FIGS. 11 and 12. This particular embodiment is preferred since it does not require a post-molding heating operation to remove the polyethylene. As shown in FIG. 11, the composite strip 34" is constructed in substantially similar manner to that of FIG. 9. Whereas a single strip of polyethylene sheet 56 was employed therein, however, in this embodiment a central magnet attachment, by strip 52, or the like, and magnet 60 is employed and a pair of strips 70 of the same polyethylene material are employed. The outer portion and method of attachment to the equal strips 54 of the backing strip 36 are identical; however, the inner edge 72 goes over the edge of the fastener strip 42 up to the point where the hooks 32 begin. The hooks 32 are, therefore, exposed at all times. Accordingly, no process is necessary to remove the polyethylene sheet 56 therefrom as in the prior art and previous embodiment. During the molding process, this construction results in two gaskets being formed on each side of the groove 20. The first or outer gasket is as described with respect to the embodiment of FIGS. 9 and 10 and is formed by the unattached outer edge 68 of the strips 70. The second or inner gasket is formed by the inner edges 72 curling and deforming from the heat of the process in the manner shown in FIG. 12. As a result, the double-gasketing system of the embodiment of FIGS. 11 and 12 prevents the flow of the foam-forming liquid therethrough and, accordingly, total coverage of the hooks 32 is unnecessary.

Thus, it can be seen that the present invention provided a valuable improvement over the prior art and accomplishes its desired objectives.

A touch fastener, as used in this application, comprises a first planar backing material having a surface carrying large plurality of hooks, mushrooms, balls on stems, pigtails, or the like capable of engaging loops, hooks, mushrooms, balls on stems, pigtails, or the like, carried by a second planar backing material to fasten components together.