Mechanical closure part

Abstract

The invention relates to a mechanical closure part comprising a support part and a plurality of closure elements which extend away from the support part via stems and are provided with a head part (2) respectively on the free ends thereof. Said closure elements are subdivided on the support part into groups (4) which form a fictitious annular arrangement in the form of a multi-cornered element comprising corners equipped with a closure element. The invention is characterised in that a group of closure elements (6) is formed within the respective groups (4), the head parts (2) thereof in the non-actuated state of the closure, adjoin each other in an adjacent manner.

Description

The invention relates to a mechanical closure part comprising a backing and a plurality of adhesive elements which extend away from the backing via stems and on their free end are each provided with a head part, the adhesive elements on the backing being arranged so as to be able to be subdivided into groups which form an imaginary ring arrangement in the form of a polygon with corners occupied by an adhesive element.

Such touch-and-close fastener parts are a component of touch-and-close fasteners, as have become widely known under the trademark name “Kletten.” The adhesive elements, which are joined with their stems to the backing, form, with their head parts, closure bodies which can preferably have the shape of mushroom heads, but also of hooks or loops. Here the adhesive elements with stem lengths, which are often less than 1 mm, are arranged distributed densely packed on the backing such that the interlocking bodies of the head parts engage the mating elements of another touch-and-close fastener part, which completes the touch-and-close fastener by interlocking.

One of the criteria for good performance characteristics of touch-and-close fasteners is that for actuating the closure, the interlocking engagement takes place securely and easily even if, in the effort to make available a high holding force of the actuated closure, the adhesive elements are arranged very densely packed on the backing. The demands for high packing density and for ease of actuation of the closure with low expenditure of force are, however, mutually conflicting.

If the touch-and-close fastener parts are placed against one another for closure actuation, there is a certain probability that head parts will meet head parts flush with each other. In order to achieve interlocking engagement, a type of displacement to clear the engagement path must take place. Especially for high packing density, a correspondingly high actuating force is thus necessary. If high actuating forces are tolerated, which is acceptable in certain applications, in the actuated state often such high holding forces result so that an easy release of the actuated fastener is prevented or made difficult.

With respect to this problem, it is prior art to provide the adhesive elements on the backing in a pattern arrangement which deviates from a regular matrix. In this respect, in document DE 603 10 529 T2, a touch-and-close fastener part of the initially mentioned type is disclosed in which the adhesive elements are arranged in groups of four adhesive elements each, the adhesive elements of each group being located on the corners of an almost square rectangle.

A generic touch-and-close fastener part is disclosed in DE 94 12 526 U1. The known touch-and-close fastener part or fastening part has a base and several essentially pin-shaped anchoring elements provided with heads, which are adjacent to one another and which project from the base. A group of first anchoring elements is located at positions on the surface of the base such that they form the corner points of essentially regular hexagonal patterns. The arrangement of the first anchoring elements is determined by a basic pattern defined by regular hexagons which border one another and thus have one side or corner in common, or defined by concentric circles. Furthermore, in each of the polygonal patterns, there is at least one second anchoring element in a position offset from the center point. In this way, a fastening device with fastening parts exhibiting anchoring elements is formed which has a relatively high retaining force even in the shear direction.

On the basis of this prior art, the object of the invention is to make available a touch-and-close fastener part which is characterized by especially good performance characteristics with reference to safe and convenient actuation with low expenditure of force which is required for interengagement and in which the holding forces desired at the time can be implemented.

This object is achieved according to the invention by a touch-and-close fastener part having the features specified in claim 1 in its entirety.

Accordingly, the invention calls for one adhesive element grouping at a time to be formed within the groups in the form of a polygonal ring arrangement with corners occupied by adhesive elements, the head parts of the grouping adjacently meeting one another in the unactuated state of the touch-and-close fastener. Such a pattern arrangement, in which both groupings with adhesive elements which meet on the head side and also “freely standing” adhesive elements are contained, enables an optimum compromise between the required actuating force and the resulting holding force, especially at the high packing density of the adhesive elements which is the goal.

The subject matter of the invention according to claim 2 is also a touch-and-close fastener part of the initially named type in which the adhesive elements are arranged on the backing with a packing density of at least 150/cm².

With respect to the groupings with adhesive elements which meet on the head side, the arrangement can be made such that the adhesive element groupings are formed by pairs of adhesive elements or from three adhesive elements.

In groupings formed from pairs of adhesive elements, each group can have preferably at least six corners occupied by an adhesive element, in each group the adhesive elements of at least two corners forming a pair of adhesive elements with adjoining head parts.

In preferred exemplary embodiments, the adhesive elements have head parts in the shape of mushroom heads.

The material for the adhesive elements is preferably isotactic polypropylene.

In exemplary embodiments with groupings of adhesive elements in the form of pairs of adhesive elements, the arrangement is preferably made such that the groups of adhesive elements form hexagons with unequal sides with two groupings of adhesive elements each, with pairs of adhesive elements adjoining their head parts.

Especially good performance characteristics can be achieved when the individual adhesive elements, which are located between the pairs of adhesive elements of the groups, have a greater distance from one another than from the respectively adjacent pairs of adhesive elements.

According to the art shown in document DE 102 40 986 B3, the backing can be formed from warp, weft, and pile threads, especially in the form of a W-weave. Here the loops of the pile threads, which project over the base fabric, are cut off. The thread ends formed in this way are thermally treated in order to form adhesive elements with head parts in the form of interlocking bodies, especially in the shape of a mushroom head.

The arrangement can advantageously be made such that the warp and weft threads are multifilaments and that the pile thread, made preferably as monofilament, has a diameter of approximately 0.20 mm.

In especially advantageous exemplary embodiments, the warp threads and weft threads have 200 and 110 dtex, the pickage for the weft threads being approximately 23 picks/cm.

The invention is detailed below using exemplary embodiments shown in the drawings.

FIG. 1 shows in a highly schematically simplified and greatly enlarged sketch the pattern arrangement of adhesive elements according to one exemplary embodiment of the touch-and-close fastener part according to the invention;

FIG. 2 shows a representation of the pattern arrangement of a second exemplary embodiment which corresponds to FIG. 1, and

FIG. 3 shows a schematic and highly enlarged side representation of a pile weave for producing the touch-and-close fastener part according to the invention, with only pile and warp threads being shown.

FIG. 1 illustrates the pattern arrangement of the adhesive elements of a first exemplary embodiment of the touch-and-close fastener part according to the invention. Of the adhesive elements, in FIG. 1 circles indicate only the head parts 2, which—on the ends of the stems which are not visible—form mushroom head-like interlocking bodies. In the example of FIG. 1, the arrangement of the adhesive elements can be divided into groups 4, which depict a ring arrangement in the form of a hexagon with unequal sides, whose six corners are each occupied by the head part 2 of an adhesive element. The hexagonal shape has two shorter sides opposite one another, as a result of which the head parts 2, which are located on the corners of these short sides, meet one another. Thus, within each group 4, two groupings of adhesive elements are formed, consisting of one pair 6 of adhesive elements each. For the sake of clarity, not all of these pairs 6 of adhesive elements are numbered in FIG. 1. As FIG. 1 illustrates, a pattern arrangement is formed in which following groups 4 extending horizontally in the figure, groupings, which are formed from pairs 6 of adhesive elements, alternate with individual head parts 2, so that the head parts 2 which do not belong to pairs 6 have a greater distance from one another than from the respectively adjacent pairs 6. As has been shown, this pattern arrangement in which “free-standing” head parts 2 alternate in the illustrated manner with groupings formed by pairs 6 of adhesive elements, which meet one another on the head side, offers optimal conditions with respect to closure actuation by inducing the interlocking engagement with comparatively low expenditure of force, in spite of an arrangement of adhesive elements in high packing density of, for example, more than 150 adhesive elements per cm². In this type of pattern arrangement, the holding forces which are favorable for the performance characteristics can also be implemented.

FIG. 2 illustrates another exemplary embodiment in which groups 4 in turn define a ring arrangement in the form of a hexagon with unequal sides, whose corners are occupied by a head part 2 of a pertinent closure element. In the rectangular shape of FIG. 2, there are two long sides opposite one another, while there are two short sides between the long sides on either side. In turn, each corner is occupied by head part 2 of one adhesive element. Due to the reduced distance of the corners on the four shorter sides, on the three corners separated by the long sides, one grouping at a time is formed in the form of a triplet of adhesive elements in which three head parts 2 meet one another in sequence. Thus, in this exemplary embodiment, alternating rows 8 are formed of densely packed head parts 2, which alternate with rows which form free spaces. Depending on the choice of the length of the two long sides of the hexagonal shape and thus of the width of the free spaces formed between the rows 8, the properties of the closure can be optimized with respect to holding force and actuating force.

FIG. 3 illustrates only warp threads 12 (not all numbered) from the base fabric of a backing 10 which bears the adhesive elements, provided with pile threads 14 in the form of a W-weave, the pile threads 14 forming loops 16 which project over the base fabric. Warp, weft, and pile threads can be formed from an isotactic polypropylene, the warp and weft threads preferably being multifilaments, while the pile thread 14 is preferably made as a monofilament and has a diameter of approximately 0.20 mm. In these materials, adhesive elements can be formed from the loops 16 of the pile thread 14 by means of the art known from DE 102 40 986 B3. When the loops 16 are cut off by a thermal cutting process to form the adhesive elements, the free loop ends can be caused to shrink by further heating, with the ends being able to form closure bodies of preferably mushroom-like shape or also closure hooks.

At diameters of the pile thread 14 of approximately 0.20 mm, and for warp threads and weft threads which have 200 and 110 dtex respectively, packing densities of the formed adhesive elements of more than 150/cm² can be implemented. The pickage for the well threads, which are not shown in FIG. 3, can be in the region of 23/cm.

It goes without saying that instead of pile weaves in the form of a W-weave with a gauze weave pair, there could be other types of weaves and/or that any appropriate plastic materials are suitable, especially for the base fabric of the backing 10.

Claims

1. A mechanical closure part comprising a backing (10) and a plurality of adhesive elements which extend away from the backing (10) via stems and on their free end are each provided with a head part (2), the adhesive elements on the backing (10) being arranged so as to be able to be subdivided into groups (4), which form an imaginary ring arrangement in the form of a polygon with corners occupied by an adhesive element, characterized in that within the respective groups (4) an adhesive element grouping (6) is formed whose head parts (2) adjacently meet one another in the unactuated state of the touch-and-close fastener.

2. The mechanical touch-and-close fastener part comprising a backing (10) and a plurality of adhesive elements which extend away from the backing (10) via stems and on their free end are each provided with a head part (2), the adhesive elements on the backing (10) being arranged so as to be able to be subdivided into groups (4), which form an imaginary ring arrangement in the shape of a polygon with corners occupied by an adhesive element, characterized in that the adhesive elements are arranged on the backing (10) with a packing density of at least 150/cm2.

3. The mechanical touch-and-close fastener part according to claim 1, characterized in that the groupings of adhesive elements are formed by pairs (6) of adhesive elements or from triplets which have three adhesive elements.

4. The mechanical touch-and-close fastener part according to claim 3, characterized in that each group (4) has at least six corners occupied by an adhesive element, and that in each group (4) the adhesive elements of at least two corners form a pair (6) of adhesive elements with adjoining head parts (2).

5. The mechanical touch-and-close fastener part according to claim 1, characterized in that adhesive elements are provided with head parts (2) in the form of mushroom heads.

6. The mechanical touch-and-close fastener part according to claim 1, characterized in that the adhesive elements are formed from isotactic polypropylene.

7. The mechanical touch-and-close fastener part according to claim 1, characterized in that the groups (4) of adhesive elements form hexagons with unequal sides with two groupings of adhesive elements each with pairs (6) of adhesive elements adjoining their head parts (2).

8. The mechanical touch-and-close fastener part according to claim 7, characterized in that the individual adhesive elements which are located between the pairs (6) of adhesive elements of the groups (4) have a greater distance from one another than from the respectively adjacent pairs (6) of adhesive elements.

9. The mechanical touch-and-close fastener part according to claim 1, characterized in that the backing (10) is formed from warp (12), weft, and pile threads (14), especially in the form of a W-weave, the loops of the pile threads (14) which project over the base fabric being cut off and the thread ends formed being thermally treated in order to form adhesive elements with head parts (2) in the form of interlocking bodies.

10. The mechanical touch-and-close fastener part according to claim 9, characterized in that the warp (12) and weft threads are multifilaments and that the pile thread (14) made preferably as a monofilament has a diameter of approximately 0.20 mm.

11. The mechanical touch-and-close fastener part according to claim 9, characterized in that the warp threads (12) and weft threads have 200 and 110 dtex, respectively, and that the pickage for the weft threads is approximately 23 picks/cm.