hasp

Abstract

This invention relates to a fastener comprising at least one planar carrier portion, on one side of which a plurality of mushroom-shaped fastener elements are provided. Each fastener element, as a one-piece component of the carrier portion, has a solid handle portion extending along a longitudinal axis in a hyperboloidal configuration. A head is connected to the free end of the handle portion, the head portion protruding at least partially from the handle portion with its edge region forming a hook-and-loop portion, and the head portion having a recessed recess on its top surface. The invention is characterized by a plurality of additional recessed recesses introduced on the opposite side of the carrier portion to the fastener elements, wherein, in at least a portion of the fastener elements, these additional recessed recesses extend concentrically or substantially concentrically about the longitudinal axis of their respective handle portions, and the maximum depth of the additional recessed recesses is between 30% and 60% of the thickness of the carrier portion.

Description

Technical Field

[0001] The present invention relates to a fastener comprising at least one planar carrier portion, wherein a plurality of mushroom-shaped fastener elements are provided on one side of the carrier portion. Background Technology

[0002] A method for manufacturing the hook and loop fastener or adhesive hook and loop fastener is known from DE10039937A1. The known adhesive hook and loop fastener comprises a plurality of hooking devices integrally connected to a carrier and symmetrically constructed. Each hooking device is in the form of a handle with a head. To implement the manufacturing method, formable material is fed into a forming area between an extrusion tool and a forming die. Because in the known solution—at least in a longitudinal sectional view of the respective die cavity—the opposing boundary walls are continuously provided with convex trajectory lines, a transition portion is created between the cross-sectional shapes of the handle and the head of the carrier with respect to a respective hooking device, thereby enabling an unobstructed demolding process.

[0003] Earlier solutions for fasteners with handles that extend in a substantially straight line are found in other published texts, such as DE196 46 318 A1. Summary of the Invention

[0004] Based on existing technology, the objective of this invention is to further improve known solutions to achieve fasteners with greater functionality and a wider range of applications.

[0005] The aforementioned task is achieved by a fastener according to the invention. In this fastener, a plurality of additional recessed recesses are introduced on the opposite side of the carrier portion to the fastener element. In at least a portion of the fastener element, these two recessed recesses extend concentrically or substantially concentrically about the longitudinal axis of their respective handle portions. The maximum depth of the corresponding additional recessed recesses is between 30-60% of the thickness of the carrier portion, preferably 50% of the thickness of the carrier portion. This provides additional functionality relative to the otherwise flat side of the carrier portion, and further expands the application range of this fastener.

[0006] First, the additional recessed areas on the back of the carrier section significantly reduce weight, enabling the achievement of basis weights (in g / m²) on the order of standard paper used in copiers and printers. 2 (Unit: mass / area); i.e., value < 80g / m² 2Since this type of fastener is a mass-produced product and must be transported, for example, in rolls of thousands of square meters to its respective application location (automotive industry, diaper industry, clothing industry, etc.), transportation costs can be significantly reduced without compromising the technical characteristics of the fastener, which are that it forms an adhesive fastener with a loop or ring-shaped product of a third component that can always be separated again; this is also known in technical terms as Kletten. ® The adhesive fastener is known to end consumers. Weight reduction is also aided by the recessed portion on the head side in the form of a cavity.

[0007] The additional recessed recesses in the carrier section not only reduce weight but also require less plastic material overall to produce the fasteners using known manufacturing methods (cold roll process), which helps reduce costs and environmental impact.

[0008] Furthermore, it has been shown that the carrier portion of the fastener with additional recessed or concave portions has a lower bending stiffness than known fasteners manufactured, for example, according to the teachings of DE10039937A1. This is important in so-called "soft" solutions where such fasteners are used for incontinence diapers and baby diapers, which, as functional items, should provide greater comfort to the wearer through their softness.

[0009] Furthermore, the corresponding additional recessed recesses also create the possibility of constructing collection cavities or storage sections, for example, to accommodate adhesive required to enable the subsequent installation of the corresponding fastener onto a third component at its point of use. In known solutions, the fastener always requires an adhesive coating layer to be more or less completely planar on the back side of the carrier portion, which increases the amount of adhesive required and thus the overall product cost, and may also result in undesirable peeling of the adhesive coating, which is avoided by the solution according to the invention, since the adhesive coating is largely protected by the corresponding additional recessed recesses. Furthermore, as exemplarily shown in DE102004058257B4, an improved feasible solution involves laying multiple film-like plastic webs for adhering the fasteners stacked on the back, wherein the outer carrier layer can be "hooked" to the inner carrier layer via the additional recessed recesses, thereby achieving improved adhesion of the stacked film-like carrier webs or carrier layers for the fastener product.

[0010] In the fastener according to the invention, the maximum depth of the corresponding additional recessed recess is specified to be between 30% and 60% of the thickness of the carrier portion, preferably 50% of the thickness of the carrier portion. In particular, in the wall thickness selection described for the carrier portion, a harmonious recessed extension for the corresponding additional recessed recess is presented in the carrier portion.

[0011] The corresponding additional recessed portion extends substantially concentrically with the handle of the respective mushroom-shaped hook and loop element, with its bottom and other recesses protruding from the carrier portion adjacent to the recess and integrally connected to the carrier portion. This creates a bridge-like structure in cross-section, on which the hook and loop element can be supported, resulting in increased support force in the longitudinal direction toward the corresponding handle in the load direction on the hook and loop element, thus improving the hook and loop characteristics. Preferably, it is specified here that a recess is provided in conjunction with each hook and loop element, and all hook and loop elements are constructed identically, and all recesses are also constructed identically to each other. This achieves a regular construction for the respective hook and loop elements as a whole, along with a high degree of symmetry along the longitudinal and transverse axes of the hook and loop elements.

[0012] As explained, the functionality of this new generation of fasteners is improved, and the potential application areas of fasteners with recessed or sunken features on the back side are also increased. The additional recessed features can be mechanically introduced into the carrier portion from the outside without problems, for example, by pressing protrusions on an additional forming roller into the still plasticized rear region of the carrier portion, so that the additional recessed features are introduced into the plastic material and in a manner that compresses the plastic material. Another feasible manufacturing method is to expel the material in the rear region of the carrier portion by applying a fluid (water, air, etc.) under high pressure using a nozzle, while simultaneously creating the aforementioned recesses. However, this manufacturing method ultimately cannot reduce the weight of the corresponding fastener because the plastic material is essentially only expelled rather than removed from the fastener itself. In contrast, there are feasible solutions within the scope of etching processes, as known from micro-plating, to remove the plastic material on the back of the carrier portion to create the corresponding additional recessed features. Removing the plastic material reduces the weight of the fastener.

[0013] However, surprisingly to those skilled in the art of adhesive hook and loop fasteners, it is possible to manufacture the additional recessed or sunken portion in the carrier portion—preferably opposite the corresponding mushroom-shaped structure—with proper control of the manufacturing process. The demolding process on the molding roller having cavities for the handle and head can be controlled such that, upon pulling out the hook and loop material, resistance is created in the corresponding cavity of the molding roller during demolding, causing the underlying plastic material to be pulled in recessedly, thereby quasi-automatically generating the corresponding additional recessed or sunken portion in the carrier portion from the back during the molding process. This is not present in the prior art.

[0014] In a preferred embodiment of the fastener according to the invention, the corresponding additional recessed portion extends continuously without protrusion from the other side of the carrier portion, extending flatly, until the bottom of the recess. Since no protruding recessed edge is produced during the manufacture of the fastener, further processability of the fastener is not impaired.

[0015] In another preferred embodiment of the fastener according to the invention, the corresponding additional recessed portion ideally transitions from a convex to a concave curved extension in the longitudinal cross-section, extending from the other side of the carrier portion toward the bottom of the recess. This produces a harmonious curved extension in the form of a sine or cosine curve, and low material stress along the recess configuration. It has proven particularly advantageous that the concave curved extension in the middle is less strongly curved compared to the convex extension adjoining the edge side of the concave curved extension.

[0016] In another preferred embodiment of the fastener according to the invention, when viewed in the longitudinal direction of the carrier portion corresponding to the manufacturing direction, and also in the longitudinal cross-section, the corresponding additional recessed portion extends more gently toward the other side of the carrier portion on one side than on the opposite cross-sectional side. This recessed configuration is generated within the demolding process of the fastener element from the forming roller, which facilitates an unobstructed demolding process.

[0017] In another preferred embodiment of the fastener according to the invention, the corresponding handle of the fastener element constitutes a uniformly extending rotating body at least at its transition portion toward the foot side of the carrier portion, which has a smaller bend than the transition portion of the handle widening toward the head side, the widening portion having the hook portion of the fastener element, and the bend extending at each of the adjacent opposing recesses is smaller than the bend associated with the head side bend extension of the handle. Thus, a compromise is achieved between the unimpeded demolding of the corresponding fastener element from the mold and the simultaneous formation of the recess in the corresponding additional recess of the carrier portion.

[0018] In another preferred embodiment of the fastener according to the invention, the maximum diameter of the additional recessed portion at its opening to the other side of the carrier portion is greater than the diameter of the handle portion at any point between its foot side and its head side, and preferably greater than the extension dimension of the head at its widest point. Thus, good hooking capability is provided on the one hand by means of the corresponding head, and good support is provided by the bridge-like transition from the flat back side of the carrier portion toward the bottom of the recess. Attached Figure Description

[0019] The fastener according to the invention, along with its manufacture, will now be described in more detail with the aid of embodiments. Here, the figures are shown in principle and not to scale:

[0020] Figure 1 A strongly schematic, simplified, and partially sectional side view shows an apparatus for implementing a method for obtaining a fastener according to the invention;

[0021] Figure 2 Presented with a strongly magnified diagram based on Figure 1 The diagram shows a longitudinal sectional view of the mold cavity;

[0022] Figure 3 Showing the ability to be based on Figure 2 Individual fastener elements manufactured using a mold cavity;

[0023] Figure 4 Showing according to Figure 3 Bottom view of the fastener element;

[0024] Figure 5 A top view of each hook and loop element is shown, wherein one of the hook and loop elements is in... Figure 3 As shown in the image. Detailed Implementation

[0025] Figure 1 The diagram schematically illustrates components of an apparatus for implementing a method for obtaining a latching fastener according to the invention. The apparatus includes an extruder head 1 as a feeding device for a plastic or liquid, particularly thermoplastic, plastic, which is fed as a strip into the gap between an extrusion tool and a forming die. The width of the strip corresponds to the width of the latching fastener or adhesive fastener to be manufactured. A pressure roller 3 is provided as the extrusion tool, while the forming die is a forming roller, integrally indicated by reference numeral 5. These two rollers are positioned along... Figure 1The rotation direction indicated by the arc arrows 7 and 9 is driven, so that a conveying gap is formed between the two rollers. The plastic strip is conveyed in the conveying direction through the conveying gap, and at the same time, the plastic strip is formed into the carrier part 10 of the fastener in the gap, which is the forming area. The carrier part 10 obtains the shape required for forming the fastener by the forming element of the forming roller 5 on the side abutting against the forming roller 5.

[0026] For this purpose, the forming roller 5 has a grid screen 11 with various mold cavities 12 on its periphery. Figure 2 An example enlarged view of one of the said mold cavities 12 is shown. Furthermore, each mold cavity 12, not shown in detail, is regularly distributed on the outer periphery of the forming roller 5 having its grid screen 11, wherein the distribution and number can be freely chosen.

[0027] Figure 2 A longitudinal sectional view of the corresponding mold cavity 12 is shown again, in which the opposing boundary walls 13 are continuously provided with convex trajectory lines 14. Naturally, the two boundary walls 13 mentioned are only part of the final forming wall 15 due to the rotational symmetry of the mold cavity 12, which is bounded by the grid material 11 of the forming roller 5. The mold cavity 12 can in any case produce a snap-on element in the form of a corresponding handle 17 with a head 16, wherein the head 16, handle 17, and opposing carrier portion 10 transition into each other in one piece. Therefore, Figure 1 The forming apparatus shown allows for the manufacture of fasteners according to the invention within the scope of casting or extrusion methods, which is also known in technical terms as the cold roll manufacturing method.

[0028] In addition, such as Figure 2 As shown, here, the corresponding trajectory line 14 is oriented towards the head 16 to be formed (in Figure 2 Looking upwards, the upper region bends more strongly than towards the foot 18, and the handle 17 is connected to the carrier portion 10 via the foot on the foot side or the bottom side. It has also proven particularly advantageous for fasteners to be manufactured by a molding device to have a stronger bend in the trajectory line 14 above the middle, preferably starting from the upper third, when viewed from the longitudinal direction of the handle 17 towards the head 16.

[0029] To obtain the aforementioned mold cavity 12 with a rotationally symmetric structure in the form of a hyperboloid, an electroplating coating process has proven effective. In this process, a cylindrical mold cavity (not shown) is first coated with a coating material until a convex trajectory line 14 is formed. Alternatively, if necessary, the convex trajectory line 14 can also be produced from a solid material such as a sieve or grid using a laser or etching process.

[0030] Figure 3The single fastening element shown—a large number of such fastening elements are located on the upper side of the carrier portion 10—can be used in the manner described above according to... Figure 1 The symmetrical structure is obtained directly by using a manufacturing apparatus according to... Figure 2 The fastener is manufactured in the mold cavity 12. The fastener element can be constructed geometrically very small, for example, having only a height of 0.4 mm and a width of the fastener head 16 arranged in a 0.6 mm dimension. In this embodiment, the cross-section of the handle 17 is approximately 0.25 mm. In contrast, the thickness of the carrier portion 10 can be constructed even smaller, for example, having a thickness between 0.05 mm and 2 mm. The above dimensions should be considered only as working examples; of course, different size proportions can also be achieved here.

[0031] In addition, according to Figure 5 As shown in the diagram, multiple such fastening elements can be disposed on the carrier portion 10. The head 16, which is hexagonal in top view, requires no further processing. Instead of the hexagonal shape, other head geometries can be easily achieved for the corresponding head 16 by means of the described molding method. Since the grid 11 is supported on a solid molding roller 19, air is contained between the top surface of the corresponding head and the outer peripheral side of the roller 19, causing the air to be compressed towards the center of the top side of the head and forming a recessed, convex notch or recess 20, which helps to increase rigidity toward the edge of the head 16. As shown, the edge of the corresponding head 16 protrudes from the handle 17 on the edge side and thereby forms a surrounding anti-hook structure 21 for interaction with the head material or ring material (not shown) of the corresponding fastening element, thereby achieving an adhesive fastener that can be reopened and closed. Other head geometries can also be achieved if required.

[0032] from Figure 2 It can also be seen that an additional recessed portion 23 is provided on the other side 22 of the carrier portion 10 opposite to the fastening element. Figure 4 The bottom view of the carrier portion 10 is shown as an example. Of course, in view of the plurality of fastening elements erected on the carrier portion 10, there are also a corresponding plurality of additional recessed portions 23 in the carrier portion 10. In other locations, the top surface 26 and the bottom surface 22 of the carrier portion 10 extend parallel to each other in planar plane.

[0033] The corresponding additional recessed portion 23—originating from the other side 22 which extends flatly from the carrier portion 10—continues continuously to the bottom 24 of the recess. According to... Figure 3As seen in the longitudinal sectional view, the corresponding additional recess 23 extends from the other side 22 of the carrier portion 10 towards the bottom 24 of the recess, transitioning from a convex to a concave curved extension. Here, it has proven advantageous in manufacturing technology that the concave curved extension in the region of the bottom 24 of the recess is less pronounced than the convex extension. However, other trajectory lines and curved extensions can be selected according to process requirements; in the current case, the curved extension is observed from the inside of the carrier portion 10.

[0034] In addition, Figure 3 Looking upwards, the corresponding recessed portion 20 is on one side of the longitudinal cross-section of the carrier portion 10 in the longitudinal direction 25 corresponding to the manufacturing direction (here in... Figure 3 Looking upwards, to the right) is more accurate than on the opposite cross-sectional side (in... Figure 3 Looking upwards, the left side rises more gently. For simplicity, Figure 3 What is not shown is that, preferably, the corresponding additional recess 23 has a maximum pit depth between 30% and 60% of the thickness of the carrier portion 10, preferably about 50%. However, particularly... Figure 4 As shown, the corresponding additional recessed portion 23 extends substantially concentrically with the handle portion 17 of the hook and loop element, which is respectively configured as a mushroom head, with its recessed bottom 24 and the remaining recess extending to the edge of the recess. As already explained, the hook and loop element protrudes from the carrier portion 10 to a predetermined degree and is integrally connected to the carrier portion 10 adjacent to the additional recessed portion 23.

[0035] Preferably, each hook and latch element is provided with one additional recessed portion 23, and all hook and latch elements are preferably constructed identically, as are all the additional recessed portions 23. This also applies accordingly to the convex recesses 20 on the head side of the corresponding head 16 of the hook and latch element. For example, particularly... Figure 3 As further shown, the corresponding handle 17 of the hook element forms a uniformly extending rotating body at least at its foot-side transition portion in the form of a foot portion 18 facing the carrier portion 10, wherein the transition portion 18 has a smaller bend compared to the transition portion of the handle 17 widening towards the head side, the widening portion having the hook portion 21 of the hook element. Furthermore, the bending extension of the handle 17 is preferably smaller at each location of the adjacent opposing recessed recesses 23 than the bending associated with the head-side bending extension of the handle 17, thereby achieving a particularly high hook strength for the hook element according to the invention. Advantageously, in this case, the deepest portion of the convex recessed recess 20 is positioned opposite the deepest point of the other recessed recess 23 at a predetermined axial distance formed by the length of the handle 17.

[0036] As from Figure 3As can be further seen, the maximum diameter of the additional pit-shaped recess 23 at the outlet portion toward the other side 22 of the carrier portion 10 is greater than the diameter of the handle portion at any point between its foot side 18 and its head side 16. Preferably, the diameter of the additional pit-shaped recess 23 is greater than the extension dimension of the head 16 at its widest portion (not shown).

[0037] The plastic used for the fasteners is preferably a material with an elongation at break greater than 30%, and the dimensions and thicknesses given above are preferably measured using a Wolff Measurement Technology DM2000 thickness gauge. In addition to general plastic materials used in the manufacture of such fasteners, biodegradable materials may also be considered, preferably those that can be manufactured based on renewable or petrochemical raw materials or a combination of both.

[0038] At 27 demolding locations (see...) Figure 1 —At the demolding position, the fastener is demolded from the mold cavity 12 of the grid 11 —the fastener is still in a partially malleable state and has not yet fully hardened. The anti-hook structure 21 remains temporarily attached to the cavity 15 of the corresponding mold cavity 12 (see Figure 2 Therefore, longitudinal stretching motion is caused on the other side 22 of the lower part of the carrier portion 10 via the handle 17, thereby pulling the additional recess 23 in the concave shape into the bottom of the carrier portion 10. Subsequently, after demolding, a restoring motion occurs due to the elasticity of the plastic material, and the fastener with its corresponding fastening element finally occupies the position according to... Figure 3 The shape.

[0039] Another feasible solution for introducing the additional pitted or recessed recess 23 is to use it for the pressure roller 3 and / or the demolding roller 28 (see...). Figure 1 A protrusion (not shown) is provided on the outer peripheral side, the protrusion corresponding to the contour of the additional recessed recesses 23 to be introduced, and then the protrusion is pressed into the back side of the carrier portion 10 by rollers 3 and 28 respectively. Thus, the corresponding additional recessed recesses 23 can also be introduced into the carrier portion 10 at a location other than the extension of the handle portion 17. Such pressed-in recesses can also be combined with the additional recessed recesses 23, which are created, for example, when the fastener is pulled out of the cavity of the forming roller 5 as described. In an embodiment not shown in detail, such recesses can also be additionally or alternatively introduced into the back side of the carrier portion 10 by means of a nozzle rod, wherein the recesses are pressed into the other side 22 of the carrier portion 10 by means of a pressurized medium (air, water) applied in a jet-like manner. Furthermore, the corresponding additional recessed recesses 23 can be manufactured in the carrier portion 10 by means of etching or other removal methods, which are also not shown.

Claims

1. A fastener comprising at least one planar carrier part (10) which is provided on one side with a plurality of mushroom head-like fastener elements which each have a solid shank (17) configured in the manner of a hyperboloid of revolution which extends along a longitudinal axis, a head (16) being connected to the free end of the shank, the head projecting at least partially beyond the shank (17) with its edge region which forms a hooking structure, and the head has a dimple-like recess (20) in the top surface of the head, characterized in that On the other side (22) of the carrier part (10) opposite the snap elements, a plurality of further concave recesses (23) are introduced, which, at least in a portion of the snap elements, extend concentrically or substantially concentrically with respect to the longitudinal axis of the respectively assigned shank part (17) and the maximum pit depth of the respective further concave recess (23) is between 30 and 60% of the thickness of the carrier part (10).

2. The fastener of claim 1, wherein The respective further concave recess (23) extends continuously from the other side (22) of the carrier part (10) extending flat without protruding therefrom up to the pit bottom (24).

3. The fastener of claim 1 or 2, wherein The respective further concave recess (23) ideally transitions from convexly curved to concavely curved extension in the longitudinal cross section viewed from the other side (22) of the carrier part (10) in the direction of the pit bottom (24).

4. The fastener of claim 3, wherein The concavely curved extension is less strongly curved than the convexly curved extension.

5. The fastener of claim 1 or 2, wherein Viewed in the longitudinal direction (25) of the carrier part (10) corresponding to the manufacturing direction, and also in the longitudinal cross section, the respective further concave recess (23) emerges more gently on one side than on the opposite cross-sectional side in the direction of the other side (22) of the carrier part (10).

6. The fastener of claim 1 or 2, wherein One further concave recess (23) is present in each case in association with a snap element, and all snap elements are identically configured, and all further concave recesses (23) are also identically configured with respect to one another.

7. The fastener of claim 1 or 2, wherein The respective shank part (17) of the snap element is configured as a uniformly extending rotational body at least at its foot side transition (18) to the carrier part (10), the transition having a smaller curvature compared to the transition of the shank part (17) to the head side widening (16) having the hooking site (21) of the snap element, and the curvature of the curved extension at each site of the adjacently opposite further concave recess (23) is smaller than the curvature associated with the head side curved extension of the shank part (17).

8. The fastener of claim 1 or 2, wherein The maximum diameter of the further concave recess (23) at the emergence site to the other side (22) of the carrier part (10) is greater than the diameter of the shank part (17) at any site between its foot side (18) and its head side (16).

9. The fastener of claim 1 or 2, wherein An adhesive is introduced in the further concave recess (23).

10. The fastener of claim 1 or 2, wherein The maximum pit depth of the respective further concave recess (23) is 50% of the thickness of the carrier part.

11. The fastener of claim 8, wherein The maximum diameter of the further concave recess (23) at the emergence site to the other side (22) of the carrier part (10) is greater than the extension dimension of the head (16) at its widest site. The maximum pit depth of the respective further concave recess (23) is 50% of the thickness of the carrier part.

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