US3889322A

US3889322A - Multi-element self-gripping device

Info

Publication number: US3889322A
Application number: US378489A
Authority: US
Inventors: George C Brumlik
Original assignee: Ingrip Fasteners Inc
Current assignee: Ingrip Fasteners Inc
Priority date: 1971-10-22
Filing date: 1973-07-12
Publication date: 1975-06-17
Anticipated expiration: 1992-06-17

Abstract

A multi-element self-gripping device is disclosed and includes a plurality of upright gripping elements stiffly attached to a base which may be a common point, a line or a surface. Each of the gripping elements are elongated flat members having at least one downwardly inclined integral askewed wedge which is defined by a downwardly inclined cut in the edge of the flat member with the portion of the member above the cut bent out of plane from the flat member from one or both sides thereof. The gripping elements are adapted to penetrate and become lodged in a receiving material.

Description

United States Patent [191 Brumlik Y 1 June 17, 1975 MULTI-ELEMENT SELF-GRIPPING DEVICE I [75] Inventor: George C. Brumlik, Montclair, NJ.

[22] Filed: July 12, 1973 i 211 Appl. No; 378,489

7 Related U.S. Application Data 7 [63] Continuation of Ser. No. 191,686, Oct. 22,1971,

Parker 24/204 8/1966 Flanagan 24/204 9/1970 Pearson 24/204 Primary Examiner-Bernard A. Gelak Attorney, Agent, or Firm-Burgess, Dinklage & Sprung [57] ABSTRACT A multi-elernent self-gripping device is disclosed and includes a plurality of upright gripping elements s tiffly attached to a base which may be a common point, a line or a'surface. Each of the gripping elements are elongated flat members having at least one downwardly'inclined integral askewed wedge which is defined by a downwardly inclined cut in the edge of the flat member with the portion of the member above the cut bent out of plane from the flat member from one or both sides thereof. The gripping elements are adapted to penetrate and become lodged in a receiving material.

9 Claims, 23 Drawing Figures SHEET PATENTEDJUN 17 ms 00 o a c o o q o 00 0 V 0 0 0 "Q (b) COMPRESSED AND/OR DISPLACED ('CUINT EIRLOCKED 1 MULTI-ELEMENT SELF-GRIPPING DEVICE This is a continuation of application Ser. No. 191,686, filed Oct. 22, I971, abandoned.

BACKGROUND This invention relates to a self-gripping device having a plurality of stiffly attached flat gripping elements having askewed gripping wedges. The gripping elements are adapted to penetrate a receiving material and upon the application of a withdrawing force the entrances of the wedges act as a funnel which directs the receiving material into the wedge with a motion that may be swirling or twisting, resulting in a positive, highly efficient self-gripping action. The degree of swirling or twisting can be regulated by the geometry of the wedge. The device of the invention is thus particularly adapted for self-gripping receiving materials comprising fibers, fibrils, filaments and edges or portions of thin layers of recticular, cellular or perforated bodies.

Self-gripping devices have been known for some time but only recently have they begun to replace conventional fastening devices such as staples, nails, adhesives and the like. In general, self-gripping devices perform many unique functions which conventional fasteners cannot provide. For instance, there is unlimited freedom of self-gripping engagement over an area by virtue of the vast number of gripping sites in a receiving material. This has the effect of eliminating alignment criticalities that seriously hamper conventional fasteners, involving mating specific fastening sites such as a bore or hole with corresponding fastening devices such as a screw or bolt.

Also, a plurality of gripping elements in a selfgripping device cooperate to provide the required amount of self-gripping holding force and distribute same over a predetermined area thus avoiding localized stress concentrations such as occurs with conventional fasteners.

Another desirable feature is that the gripping elements of a device are inherently flexible which allows a self-gripping connection to accommodate dimensional changes caused by large thermal coefficients of expansion that occur between similar or dissimilar articles connected to each other by a self-gripping mechanism. This prevents buckling and cracking of joined articles.

One more capability of self-gripping devices is the ability to form a self-gripping connection between articles on any face, edge or corner by simply bringing any pair of these into contact at the desired location.

With increasing use and advancing sophistication of self-gripping devices, the ability of a self-gripping de- SUMMARY The present invention provides self-gripping devices which add new dimensions to the self-gripping art. The devices of the invention makes it possible to self-grip fibers at any given point, even fibers attached at one end and also provide for unlimited freedom of selfgripping engagement not only over an entire surface but also in depth of a receiving material.

The device of the invention includes a plurality of upright gripping elements which are stiffiy attached to a base. Each of the gripping elements comprises an elongated member having at least one flat longitudinal edge section with at least one integral askewed wedge defined by a cut in the edge of the flat section, preferably in a downwardly inclined direction, with the portion of the flat section above the cut bent out of plane from the flat section. The gripping elements are adapted to penetrate or become lodged in a receiving material and especially receiving materials made up of fibers, fibrils, filaments and thin walled cells, webs and sheets. The gripping elements are particularly adapted for self gripping fibers, fibrils, fascicles, filaments, braids, tufts, yarns, and especially any of these loose at one end. Such fibers and the like offer an infinite number of engaging sites and the devices of the invention are capable of gripping same along their entire length.

DESCRIPTION OF THE DRAWING FIG. 1a is a side elevational view showing a gripping element having .a plurality of askewed wedges along one edge thereof.

FIG. lb is a side elevational view of a gripping element curved about its longitudinal axis for increased stiffness and having a plurality of wedges along both edges thereof.

FIGS. 2 and 3 are side elevational views showing further embodiments of gripping elements suitable for use in the present invention.

FIG. 4 is a side elevational view of yet another embodiment of a gripping element suitable for use in the present invention.

FIG. 5 is an exploded view of a portion of the gripping element of FIG. 4.

FIG. 6 is a side elevational view of a gripping element used in the present invention.

FIGS. 7, Sand 9 are perspective views illustrating various configurations of the self'gripping device of the invention.

FIG. 10 is a side sectional view illustrating a particular embodiment of the invention.

FIGS. 11 a through c are perspective views illustrating embodiments of the self-gripping device wherein the gripping elements are attached to a linear member (FIG. 11a) or a common point (FIGS. 11b and c).

FIGS. 12a through h are side elevational views partly in section illustrating various profiles of filaments which provide for highly efficient self-gripping engagement with the device of the invention.

FIG. 13 is a perspective view of a receiving layer of the invention comprising filaments having striations such as shown in FIG. 12.

FIGS. 14 a through e are elevational views illustrating several ways in which loose-ended fibers are selfgripped by the askewed gripping wedges.

FIGS. 15 and 16 are side elevational views of filaments which also provide highly efficient self-gripping engagement with the device of the invention.

DESCRIPTION Referring now to the drawing and in particular to FIGS. 7 through 9 and 11, the self-gripping device of the invention is shown to include a plurality of upright gripping elements indicated generally by the reference numeral stiffly attached in thick profusion or in relatively close proximity to each other to a base which may be a surface such as the sheet shown in FIG. 7, the disc 22 shown in FIG. 8 or the strip 24 shown in FIG. 9, or a linear element such as the filament 32 shown in FIG. 11a or a common point 34 shown in FIGS. 1 lb and c. Similar or dissimilar gripping elements which can vary in size may be arranged on the base in a uniform or irregular pattern and they may extend from both sides of a base such as shown in FIG. 9 or they may. radiate about a line as shown in FIGS. 11a or about a common point such as the six-element arrangement shown in FIG. llb or the four-element tetrahedron-type arrangement shown in FIG. 11c.

Referring now to FIGS. 1-3, the gripping elements 1 of the device of the invention include an elongated fiat member 12 having at least one downwardly inclined integral askewed wedge formed by cutting the edge of the member 12 in a downwardly inclined direction at 14 and bending the portion 16 of the fiat member 12 above the cut 14 out of plane from the flat member 12. The askewed wedges formed by portions 16 and cuts 14 are shown in greater detail in FIG. 6 by the reference numeral 17. As shown in FIGS. la and lb, the askewed wedges are preferably spaced alone one or both edges of the flat member 12. As shown in FIG. 2, the askewed wedges can progressively increase in size from the tip or upper end of the flat member 12 downward. The askewed wedge can be formed using a straight angled cut 14 as shown in FIGS. 1a, lb, 2, 3 and 6 in which case the bent out portion 16 can be described as an acute angled portion.

The member 12 may also be curved as shown in FIG. 1b to increase the overall stiffness of the gripping elements 10. Also, it is only necessary that the gripping elements have one flat longitudinal edge section containing the askewed wedges described herein. Thus, the member 12 can have a curved or angled longitudinal bead or section thicker than the adjacent flat section for added strength and stiffness. The longitudinal bead or section can form one edge of the gripping element or it can be centrally located with two adjacent fiat sections on both sides thereof. It is also possible to use perforated, corrugated or similarly textured members for the gripping elements as well as composite members comprising a stiffgenerally metal core with an outer coating such as an extruded plastic sheath and the like.

The flat member 12 may also be cut along a curve as shown by reference number 13 in FIGS. 4 and 5. In this instance, the portion 11 that is bent out of plane is rounded or curved. In the embodiment shown in FIGS.

and self-gripping,is'accomplished by engagement of the receiving material with the askewed wedge. The absence of a barb is desirable to prevent skin irritation when the device of the invention is applied or utilized by hand. Thus, the invention in this embodiment provides a unique self-gripping device wherein the need for barbs can be eliminated. In another embodiment for instance as shown in FIGS. 1b and 6, self-gripping action can be accomplished by a combination of the askewed wedge 17 and the bent out portion 16 functioning as a barb.

As indicated above, the self-gripping device of the invention is especially suited for self-gripping engagement with receiving materials which are fibrous in nature and is equipped to self-grip surfaces such as those wherein the fibers, tufts, yarns and the like, are loose at one end. In FIGS. lb 2 and 3, the engagement of the wedges with a filament 18 is illustrated and in FIG. 4 a bundle of three filaments is shown being engaged by a single wedge. In FIGS. 1a and 2 filaments l8 loose at one end and attached to a base 36 on the other end, are shown gripped by the uppermost wedge of the elements 10. This general parallel engagement of a fiber is also shown-in FIG. 6. Thus, the fibers 18 can be generally parallel to the flat member 12 and still be effectively self-gripped. This is a unique capability. It should also be understood that the wedges are capable of gripping fibers and the like oriented or held in any direction or plane such as shown in FIGS. 1b, 2 and 3. Besides filaments and fibers 18, the wedges 17 are capable of engaging thin walled cells, webs and sheets as is illustrated in FIG. 6 by the thin sheet-like member 23.

A plurality of gripping elements 10, which may be the same or different, cooperate in engaging a receiving materials to distribute the self-gripping force over a given area and thus eliminate stress concentrations.

Referring now to FIG. 14 and in particular to FIG. 14e, the askewed wedge is capable of self-gripping smooth or textured filaments by one or a combination of three mechanisms depending on the depth to which the filaments or fibers reach in the wedge. As shown in FIG. 142, these mechanisms shown in the relative relationship to depth in the wedge are (a) interlocking, (b) compressed and or displaced and (c) cutting. In FIG. 14a, a textured fiber 18 attached to a base 36 is shown interlocked in the wedge defined by bent out portion 16 and segment 14 of member 12. FIGS. 14a through c are edge-on views of gripping elements 10 which are shown for purposes of illustration attached to a base 20. InFIG. 1412 a smooth fiber 18 is shown compressed and displaced at 19 between bent out portion 16 and segment 14. In FIG. 14c the fiber is drawn or forced further into the wedge and is actually partially cut by the bent out portion 16 with the portion of the fiber peeled back by the cutting action shown curled above portion 16. FIG. 14d is another view showing the relative depth of the filaments shown in FIGS. 14a and b.

directing receiving material into the wedge per se for I FIGS. 14a through c also illustrate that the cut 14 may be made at a right angle across the edge of flat member 12 as shown in FIG. 14a or at another angle greater or less than to arrive at the structure shown in FIG. 140, for example.

It is evident, therefore, that the device of the invention is not only capable of unlimited freedom of selfgripping engagement over an entire surface but also throughout the depth of a receiving material. Since each fiber loose at one end in a receiving material offers an indefinite number of engaging sites along its entire length, self-gripping engagement can take place between the very end of a filament 18 and a gripping element as shown for example in FIGS. 1a and 2 or it can occur at the base of a fiber l8 and a gripping element 10 or at any combination of sites therebetween.

Also, upon entry into a receiving material, fibers and filaments therein are effectively displaced by the entering askewed wedge and because of their physical relationship to one another in a receiving material, they tend to return to their original position which greatly enhance the probability of self-gripping engagement with an askewed wedge upon application of withdrawing force to the gripping elements.

The portions 11 and 16 may be bent out of plane from the flat member 12 from one or both sides thereof in any desired predetermined uniform, random or irregular pattern. Generally, the portions 11 and 16 above the

cuts

13 and 14 in the flat members 12 are bent out of plane a sufficient distance to form an askewed wedge capable of accommodating one or more filaments 18 as shown for example in FIGS. 1a, 1b, 2, 3 and 6. The angle of

cuts

13 and 14 in relation to the transverse portion of fiat member 12 can be 90 but are preferably downwardly inclined. The angle of the cuts Band 14 across the edge of member 12 can vary as described above.

The tip or upper end of the gripping elements 10 may be rounded as shown in FIGS. 1a and lb and 4 or they may have a sharp centrally located tip as shown in FIG. 2 or a sharp asymmetrical tip as shown in FIG. 3. The upper end of the gripping elements 10 may also be provided with a cutting edge to facilitate initial penetration into a receiving layer or material.

Generally speaking the upper end of the gripping elements 10 are characterized by a penetrating profile or shape which may be achieved by any of the shapes shown or by an angled or straight cut across the flat member 12 or forming in such a way that multiple shape points result. In those instances where skin irritation is to be avoided the upper end of the gripping elements 10 are preferably rounded as shown, for example, in FIG. 4.

As indicated above the self-gripping elements of the device of the invention are adapted to penetrate and become lodged in a receiving material which for purposes of the invention generally comprise fibers, fibrils, filaments or thin walled cells, webs or sheets all of which can enter into self-gripping engagement with the askewed wedges. in a preferred embodiment, the receiving layer or material is fibrous in nature and may have fibers, fibrils or filaments which are loose at one ,end, for example, as occurs in animal and artificial fur,

hair and in fabrics such as velvet or in woven, piled, tufted and flocked carpets.

Thus, the self-gripping device of the invention is particularly adapted for self-gripping materials such as woven, non-woven andknitted fabrics, fibers and fiber aggregates. carpets, carpet-like materials, foamed rubber and plastics, felt, wood, cork, sponge, animal and artificial fur and hair. feathers. leather, paper, card-.

board. corrugated cardboard, metal and plastic mesh, filter sheets, expanded or perforated sheet materials and composites of any of the foregoing.

The receiving material may also be a thin wall or laminae which is capable of being penetrated or pierced by the gripping element such as a sheet per se or an interior cellular wall; also included are web-like structures having thinned out or localized areas capable of being self-gripped. For example, such sheets can be a sheet with densely punched holes relatively close to each other or expanded sheets such as expanded metal.

Especially suitable receiving materials and structures are disclosed in my copending applications Ser. Nos. 126,708 and, 126,706, both filed Mar. 22, 1971, and Ser. No. 154,589, filed June 18, 1971.

The askewed wedge is formed from a flat member in such a manner that it has cutting or shearing edges. For weaker force engagement the edges could be rounded off, mechanically or by etching. This makes it possible for the askewed wedge to not only compress and/or displace or interlock with a filament (FIGS. 14a and b) but also to partially cut into the filament to obtain selfgripping (FIG. 14c). This ability to cut a fiber or filament also enables separation of a device of the invention from the receiving layer or material and because of the nature of the receiving layer or material, the ability to again enter into self-gripping engagement is not impaired by virtue of the fact that there are virtually thousands of self-gripping sites within a receiving layer or material of the nature described herein.

Referring now to FIG. 10, a self-gripping device of the invention comprising a sheet 20 and upright gripping elements 10 is shown in self-gripping engagement with a receiving layer 30 which is shown to be porous in nature for purposes of illustration.

In certain applications, it is desirable to utilize a receiving layer such as that shown in FIG. 10 as a protective layer for the gripping elements 10 which can be stripped off to prepare the device for self-gripping engagement. The use of a protective layer makes it possible to ship and handle the gripping device of the invention without irritation to the user or premature selfgripping engagement. The protective layer may have a thickness equal to or greater than the height of the gripping elements 10. Such a protective layer can be readily utilized with any of the various embodiments of the invention such as those shown in FIGS. 7 through 9, 11a and 11b for example.

It is also possible to use the receiving layer 30 as a component part of the device of the invention. In this instance the layer 30 is made of a resilient material such as felt, carpet-like materials, sponge, plastic and rubber foam and the like, that remains in place over the gripping element 10 forming what can be called a hybrid self-gripping surface. The gripping elements 10 in this embodiment can extend below to or beyond the surface of layer 30. Thus, when the layer 30 is compressed, the elements 10 are exposed and protrude out of the layer 30 and are then capable of self-gripping engagement with a receiving layer or material or a similar hybrid self-gripping device.

The gripping element used in the device of the invention may be formed or molded from a variety of materials such as metal, glass, plastics or composites of these but are preferably made of metal. Thus, the term bent out of plane, also embraces techniques where the askewed wedge is molded out of plane. As noted above, in cross-section the gripping elements have a flat longitudinal edge section which is necessary for forming the askewed wedges along the edge or edges thereof. The cross-sectional shape of the member may be varied. For example, it may be rectangular, parallelogram,

crescent-shaped, polygonal and the like with or without cutting edges on one or both edges.

In certain intances, the member 12 can be made from thin resilient metal in which case the

portions

13 or 16 will have a spring-like action enabling them to flatten out when penetrating a receiving layer or material and spring-back to their original position after insertion or upon pulling the element out.

In general, the gripping elements are sufficiently stiff such that they resist deflection which would otherwise preventthem from penetrating and becoming lodged in a receiving layer or material. It is also necessary that the gripping elements be stiffly attached to the base to enable the gripping elements to enter into self-gripping engagement. Thus, the gripping elements can be attached to a base by any suitable technique consistent with the nature of the gripping element and the base. The base itself can be fabricated from a wide variety of materials such as metal, wood, plastics, glass, paper, cardboard, porous, woven and non-woven materials and the like.

The gripping elements can be attached to the base by inserting the lower ends in a sheet, patch or strip such as shown in FIGS. 7-9, and/or by mechanical attaching the gripping elements using adhesive, welding or heat sealing techniques. In FIGS. 7-9 pairs of gripping elements may also be interconnected in a staple-like fashion.

In the embodiment shown in FIG. 11a the gripping element can be attached to the filament 32 which can be made of metal, plastic or glass using the above techniques. The same is true in the embodiments shown in FIGS. 11b and c where a plurality of gripping elements are attached at a common point 34 forming the base of the clustered self-gripping device. Suitable gripping elements and attaching techniques including staple-like structures and preformed elements are disclosed in my copending applications Ser. Nos. 171,701

filed Aug. 13, 1971, 171,668 filed Aug. 13, 1971, 179,880 filed Sept. 13, 1971, and 186,874 filed Oct. 6, 1971.

The nature of the self-gripping action by the gripping elements may be permanent or reversible depending upon the nature of the gripping elements and the receiving layers or materials which comes into selfgripping engagement therewith. For example, askewed wedges may be rigid to provide a more permanent or tenacious self-gripping action or they may be resilient to facilitate removal from a receiving layer. As noted previously, the cutting action of the askewed wedges also facilitates removal from a receiving layer.

The gripping elements generally range in length from about 0.002 to about 0.75 inch and the flat member forming the gripping element can range from about 0.001 to 0.08 inch. It should be noted that extremely small gripping elements can form the device of the invention and yet be invisible to the naked eye.

A further aspect of the present invention relates to a receiving material which is adapted to enter into selfgripping engagement with self-gripping devices including those disclosed herein or with itself and comprises a base having attached thereto in relatively thick profusion, a plurality of fibers loose at one end and having lateral protrusions.

FIG. 12 provides several illustrations of such fibers, indicated generally by the reference numeral 18, having lateral protrusions. The fibers shown in FIGS. 12a

through h can be characterized as having transverse striations which may also be crisscrossed or helical as shown, for example, in FIGS. l2e and f. The transverse striations may be angular as shown in FIGS. -0 and -h or they may be curved in cross-section as shown in FIG. 12d. The fibers 18 may be solid as shown in FIGS. 12a through f or they may be hollow as shown in FIGS. 12g and h.

In FIG. 15, another type of filament 18 is shown wherein the lateral protrusions are in the form of granules or particulate materials 40 attached to the surface of the fiber in a random or uniform pattern. Such fibers are known and have. been used to form abrasive pads. The granules 40 may be embedded in or adhesively attached to the fiber 18.

FIG. 16 illustrates a further embodiment of a composite fiber with a hightensile narrow core 44 and a deformable outer coating 42 which is capable of being displaced or cold formed, preferably without rupturing or cutting, thereby providing a projected site or lateral protrusion for self-gripping engagement with a selfgripping device. The coating 42 in practice is displaced or cold formed upon engagement with a self-gripping device such as the device of the invention. The core 44 is generally a stiff element made of wire, glass, glass yarn or plastic such as polyacetals, polyesters, polyamides, polypropylene, and yarns or the like formed from any of these. The coating 42 can be an elastomer, a tacky or pressure-sensitive material, or soft and pliable material that is resistant to peeling and stripping. Suitable materials for coating 42 include synthetic and natural rubbers, ethylene vinyl acetate elastomers, silicon resins, urethane polymers, hightack compositions, ionomer resins and the like.

It should be noted that the fibers shown in FIGS. 12, 15 and 16, for example, can also be in the form of filaments which can be spun into yarn, braided, woven, knitted, felted and the like. The filaments in any of these forms may be anchored or attached to a backing member to provide a particularly desirable receiving material for use with self-gripping devices in general.

The fibers shown in FIGS. 12 and 15 may also be composites comprising a core and an outer coating having lateral protrusions. The fibers shown in FIG. 12, for example, can be made using known techniques from metals such as aluminum, steel, copper and the like or from plastics including thermoplastics such as p'olyolefins, nylons, polyesters and the like, and thermoplastic resins such as phenolics and the like. The fibers can be formed using extrusion, melt spinning, solvent spinning, cold forming, printing, embossing, film slitting and similar techniques.

FIG. 13 illustrates this embodiment of the invention wherein fibers 18 having lateral protrusions are attached to a base 36. In this embodiment, the fibers 18 generally range in length from about 0.001 to about 0.75 inch, are closely packed on base 36 and the upper ends thereof have a penetrating profile to permit entry by gripping elements. The fibers 18 are preferably spaced no greater than one filament width apart on the base 36 and the penetrating profile can be rounded, pointed, cut-off at an angle as shown in FIG. 16, or the like.

In FIG. 13, fibers 18 can be attached to the base 36 using conventional tufting, weaving, flocking, piling, or adhesive techniques. The base 36 can be made from the same materials as the base for the gripping elements and it can be in the form of a sheet as shown in FIG. 13 or a strip or patch as illustrated in FIGS. 8 and 9. The device shown in FIG. 13 may also include other filaments which can be looped or loose at one end and may include different types of fibers having lateral protrusions which may also vary in size, including the fibers of FIG. 16 having an outer coating 42 which has a higher coefficient of friction or a pressure-sensitive force in contact.

It should be noted that the device illustrated by FIG. 13 because of the nature of the fibers 18 is inherently self-gripping to itself and it is also capable of functioning as a receiving material for self-gripping devices having gripping elements capable of engaging the fibers 18 in a self-gripping action. Such self-gripping devices include those described herein and in addition multielement self-gripping devices wherein the elements have a trough lined with an edge as disclosed in my copending application disclosed in my copending applications Ser. No. 200,366 filed Nov. 19, 1971, or a linguiform tab as disclosed in my copending application Ser. No. 295,637 filed Oct. 6, 1972.

The self-gripping devices and receiving layers of the invention may be used in a variety of ways to efficiently and quickly render virtually any surface or article selfgripping. The device of the invention can be readily used by individuals and commercial users to render selected areas of articles or entire articles self-gripping such as carpets, fabrics, felts, wall cladding materials, panels, tile, sheets, filters, decorative trim, and the like.

What is claimed is:

l. Self-gripping device comprising a plurality of upright gripping elements stiffly attached to a base, each of said gripping elements comprising an elongated member having at least one flat longitudinal edge section with at least one integral askewed wedge defined by a cut in the edge of said flat section with the portion of said flat section above the cut being rounded and bent out of plane from said flat section, said gripping elements being adapted to penetrate and become lodged in a receiving material.

2. Self-gripping device of claim 1 wherein said cut is downwardly inclined.

3. Self-gripping device of claim 1 wherein a plurality of said rounded portions are spaced along the edge of said flat section and adjacent rounded portions define a funnel to promote fiber engagement by the askewed wedge.

4. Self-gripping device of claim 1 wherein a plurality of said askewed wedges are spaced along the edge of said flat section in a uniform to irregular pattern.

5. Self-gripping device of claim 4 wherein said askewed wedges are formed from both sides of said flat section in a uniform to irregular pattern.

6. Self-gripping device of claim 1 wherein the upper end of said elongated members are rounded.

7. Self-gripping device of claim 1 having a protective layer over said gripping elements.

8. Self-gripping device of claim 1 which includes a resilient receiving material over the gripping elements forming a hybrid self-gripping device.

9. Self-gripping device of claim 1 in self-gripping engagement with areceiving material.

Claims

1. Self-gripping device comprising a plurality of upright gripping elements stiffly attached to a base, each of said gripping elements comprising an elongated member having at least one flat longitudinal edge section with at least one integral askewed wedge defined by a cut in the edge of said flat section with the portion of said flat section above the cut being rounded and bent out of plane from said flat section, said gripping elements being adapted to penetrate and become lodged in a receiving material.

2. Self-gripping device of claim 1 wherein said cut is downwardly inclined.

9. Self-gripping device of claim 1 in self-gripping engagement with a receiving material.