Separable Fastening Sheet

Abstract

In a separable fastening sheet having clasping elements which are designed to co-operate with corresponding clasping elements of another sheet and at least some of which have at their end an enlarged or bulbous terminal head connected to the base by a stem, web or foot, the heads of at least part of these elements having a widened head have at least one flexible lip or edge adapted to bend with respect to the remainder of the element for penetration of said heads between or into the corresponding elements of the other sheet and the locking thereof by the last-mentioned elements by elastic retraction of said lip on contact thereof with said corresponding elements and its at least partial return to its position of rest.

Description

This invention relates to separable fastening sheets in which the clasping elements of one sheet co-operate separably, for fastening purpose, with the corresponding clasping elements of another sheet, the elements of the two sheets being either identical or similar, or of different and complementary forms.

Among such sheets, the invention applies to those in which at least part of the elements include an enlarged terminal head which co-operates, for fastening purposes, with corresponding elements of another sheet. Connection between these heads and the base or bed is achieved by means of a thin portion. Fastening is obtained by the penetration of the enlarged heads either into the interior itself of the elements of the other sheet, or between at least two elements of said other sheet.

The invention relates both to sheets in which the clasping elements are separate and include a thin or tapered stem bearing the enlarged head, and to those in which the elements are in the form of continuous parallel profiles or ribs.

According to the present technique, so that the enlarged heads of the elements of one sheet may be able to penetrate into or between the elements of the other sheet and remain in the fixed or locking position in or between the elements for fastening purposes, it is necessary, in the case where the elements are set or distributed densely, either to give the bases or beds a certain flexibility, so that two adjacent elements of a sheet may be able to move apart for a head of the other sheet to pass between them and move nearer to one another to clamp or lock the head, in the manner of an engaging or meshing action, or that an element be able to open to receive in its interior the enlarged head of an element of the other sheet, or to produce an irregular location of the clasping elements on the same sheet or from one sheet to the other, so that the elements may be able to bend laterally in order to spread adjoining heads, filling the free spaces not furnished with elements.

The first solution has the drawback of imposing on the sheets the need for a flexible bed, which implies that the surfaces on which they are placed must also be flexible; the second solution has the drawback, because of the irregular location or distribution, on the one hand of reducing the firmness of the fixing by reason of the free spaces and, on the other hand, of increasing the cost by reason of the non-uniformity of the positioning or location.

The object of the invention is in particular to overcome these drawbacks by providing a separable fastening sheet which may not be flexible, which can be placed on a rigid surface and in which the distribution of the clasping elements is regular and uniform.

To this end, a separable fastening sheet according to the invention, having clasping elements of which some at least have at their end an enlarged or bulbous terminal head connected to the base by a stem or web and designed to co-operate with at least one corresponding clasping element of a second sheet, is characterised by the fact that the enlarged or bulbous terminal heads of at least part of the clasping elements have at least one flexible lip adapted to bend with respect to the remainder of the element for penetration of said heads between or into the corresponding elements of the other sheet and the locking thereof by the last-mentioned elements by elastic retraction or drawing aside of said lip on contact thereof with said corresponding elements and its at least partial return to its state of rest.

The heads therefore have an external form which is modified through the flexibility of their lips so that they can be inserted between or into the elements of the other sheet and return at least partly to their rest position.

The invention will be clearly understood with the aid of the following description relating to various embodiments of the invention and by reference to the accompanying drawings, in which:

FIG. 1 shows two portions of facing sheets provided with respective clasping or gripping elements and in the disengaged position;

FIGS. 2 and 3 show the sheets of FIG. 1 in the course of engagement and in the engaged position, respectively;

FIG. 4 shows a modified constructional form of the sheets of FIG. 1 in the disengaged position;

FIG. 5 shows diagrammatically in plan view a preferred location and engagement pattern for the clasping elements of the sheets of FIG. 1 to 4;

FIG. 6 shows another embodiment, the sheets being in the disengaged position;

FIG. 7 shows the sheets of FIG. 6 in the engaged position;

FIG. 8 shows diagrammatically in plan view a preferred location and engagement pattern for the elements of the sheets of FIGS. 6 and 7;

FIGS. 9, 10 and 11 show another embodiment, the sheets being respectively in the disengaged position, in the course of engagement and in the engaged position;

FIG. 12 shows yet another embodiment, the sheets being in the disengaged position; and

FIG. 13 shows another embodiment in perspective.

Referring first of all to FIG. 1, two separable fastening sheets 1, 2 are shown, each of these being constituted by a base 3, 4 bearing circular and separate clasping elements 5, 6. Each of the elements 5, 6 is constituted by a stem 7 surmounted at its end remote from the corresponding base 3, 4 by a widened or enlarged head 8 projecting beyond the contour of the stem.

The heads 8 are shown in a slightly convex form, so that the elements 5, 6 assume the shape of mushrooms, but it is understood that the heads could have any other form. As an example, in FIG. 4, in which the same references have been adopted, the heads 8 are all flat and thinned down at the edges.

This being the case, mutual fixing of the two sheets 1, 2 is achieved when the elements 5 are inserted at least partially between the elements 6 and vice versa. The engaged position of the two sheets is shown in FIG. 3.

As can be seen in FIGS. 1 and 4, the free space between the heads 8 of one sheet is smaller than a head 8 of the other sheet and vice versa, so that if the heads were rigid or not very flexible there could not be any interpenetration of the elements 5, 6 of the two sheets unless the heads of at least one sheet were to move aside by bending of their stems 7 with respect to the bases 3, 4 or unless the bases 3, 4 were flexible.

According to the invention, at least some of the heads 8 are arranged so that they comprise at least one flexible lip or edge 9 adapted to draw aside or yield on contact with the elements of the other sheet so as to permit in this way the passage of a head between heads of the other sheet without the bases 3, 4 being necessarily flexible.

As can be seen in fact in FIG. 2, the flexible lips 9 of the elements 5, 6 bend towards the bases 3, 4 when they come into contact with heads of the other sheet so as to reduce their overall size and permit the passage of a head, which is itself in a compressed state, between the adjacent heads of the other sheet.

In the engaged position, the elements 5, 6 of the sheets of FIGS. 1 to 4 occupy the relative positions shown diagrammatically in FIG. 5, in which a head of one sheet is engaged between four elements of the other sheet and vice versa, the elements of each sheet being disposed in regular lines and columns. It will be noted that FIGS. 1 to 4 correspond to views on the line A-A of FIG. 5 for the various relative positions of the sheets.

In the embodiments of FIGS. 1 to 4, all the elements of the two sheets have a circular contour in the form of a flexible lip. Various modified forms may be provided, however. For example, the heads of one sheet alone may have a flexible contour, while the heads of the other sheet may be rigid or very slightly flexible. It is also possible to provide a flexible lip only over a portion of each head. This asymmetry enables the sheets to be "oriented" with respect to one another. Whatever the constructional form adopted, however, a flexible lip 9 bends in a direction substantially parallel to its stem 7 and, therefore, perpendicularly to the corresponding base 3, 4.

The dimensions of the clasping elements 5, 6 are defined in accordance with requirements; thus, in the engaged position, the clasping elements may have a certain play, or, on the other hand, they may be under elastic tension (FIG. 3), for example by giving the slender portion of the stems 7 a small height, so that the heads 8 of one sheet bear against the base 3, 4 of the other sheet and/or so that their flexible lips do not return completely to their rest position, but are in contact with the enlarged feet of the stems.

In the embodiment of FIGS. 1 to 4, the heads 8 have been able to bend in a direction substantially parallel to that of the stems 7; it is also possible to arrange the heads so that they bend in any other direction, for example a direction perpendicular to that of the stems.

Thus, in FIG. 6, the stems 7 of the elements 5a, 6a are surmounted by a bulbous head 8a substantially in the form of a ball. The bending of the heads is obtained by hollowing out at least some of these heads 8a by means of a notch 13 communicating with the outside for ease of manufacture; if need be (FIG. 8) two notches 13 at right angles may be provided so as to obtain cruciform balls 8a. It is likewise possible to provide several notches or slots per head so as to form several flexible lips or "petals." Some at least of the heads 8a therefore have lips 14, as a whole vertical, forming petals and connected to the stems 7, the junction providing the desired flexibility. It is to be noted that the lips 14 converge towards the top of the heads and close up to avoid being torn away. As before, it is not necessary for all the heads to be flexible; in fact, a head may be only partially flexible or some heads may be rigid. To obtain rigid heads, it is sufficient not to provide any notches 13. The mutual engagement of the heads 8a is effected by transverse yeilding or drawing aside of the lips or petals 14 towards the inside and, in the engaged state, the heads occupy the position shown in FIG. 7, in which a head of one sheet is lodged between at least two heads of the other sheet.

FIG. 8 shows in plan view, in a similar manner to FIG. 5, the relative position of the elements of the two sheets in the engaged position. A head is lodged between four elements of the other sheet, the elements of the two sheets being distributed in regular lines and columns.

It is likewise possible to combine the embodiments of FIGS. 1 to 4 with that of FIGS. 6 and 7 by making a head comprise at the same time at least one vertical lip and at least one horizontal lip so as to obtain bending actions in both directions.

The invention is therefore not limited to the geometrical forms described and shown so far.

In the foregoing embodiments, the corresponding elements of the two sheets are geometrically identical. The embodiments of FIGS. 9 to 12 are similar to that of FIGS. 6 and 7, as regards the elements with an enlarged head, by the fact that the heads have lips which bend transversely. However, in these embodiments, in which the elements are likewise separate, the corresponding elements which co-operate with these elements each receive an element in their interior and are of different geometrical form.

In FIG. 9, the sheet 1 bears male elements 15 similar those of FIG. 6, while the sheet 2 bears complementary female elements 16 provided with an internal cavity 17 for receiving the head of the element 15. The entry orifice 18 is smaller than the head 15, so that penetration of the head is effected with deformation of material. The flexibility of the heads permits this deformation, the elements 16 being then non-deformable, but, if need be, the elements 16 may also be given a certain flexibility.

FIG. 10 shows the intermediate relative position of two elements 15, 16 in the course of engagement. The element 15 is partially engaged, its lips being brought together so that the head is able to pass through the orifice 18. In FIG. 11, the head has moved beyond the orifice 18 and has at least partly resumed its opened-out state in the engaged position.

In the embodiment of FIG. 12, the male elements 19 are again of the type having transverse flexibility and the female elements are formed in the thickness itself of the outer part 20 of the sheet 2. These female elements are constituted by cavities or sockets 21, the profile of which corresponds to that of the elements 19. The penetration and co-operation of the elements 19 and 21 are similar to the penetration and co-operation described in connection with FIGS. 9 to 11.

There are described in the foregoing, with reference to FIGS. 1 to 12, elements with enlarged head which are separate, in the sense that the heads are independent of one another and the elements are connected only by their base or support.

According to another constructional form of the invention, it is also possible, however, to provide not only isolated elements, but also or only elements produced in the form of continuous profiles, a profile, rim or band of one sheet penetrating either into a corresponding profile, rim or band of the other sheet or between two profiles, rims or bands of this second sheet.

Referring again to FIGS. 1, 4, 6, and 9 and 12, at least some of the profiles, rims or bands, according to this second kind of embodiments, have a constant section such as that which is shown in each of these drawings. The flexible lips then extend on the entire length of the profiles. If some elements of a sheet are not profiles, they may, for example, be of the "separate" type, but co-operate with at least one profile of the other sheet.

Thus, FIG. 13 shows clasping elements which, instead of being separate from one another, are produced, at least where some are concerned, in the form of continuous profiles. It is understood that the elements shown in FIG. 13 may be replaced by the elements the sections of which are shown in any one of FIGS. 1 to 12. By way of example, the elements 22 are separate from one another, while the elements 23 are constituted by continuous profiles parallel to one another and to the lines of elements 22. An element 22 penetrates between two profiles 23 and a profile 23 penetrates between two lines of elements 22. In the same way, all the projecting elements may be profiles.

In the case of hollow-type elements (female elements 21 of FIG. 12), the profiles are naturally replaced by grooves.

On the separation of the sheets, the lips bend or yield in the other or the same direction in a similar manner.

With sheets according to the invention, the feet, stems or webs connecting the clasping elements to their base undergo practically no elastic deformation on engagement and separation. Likewise, the nature of the bases or beds does not play any part, since their deformation is not necessary; it is therefore possible to use rigid bases or, in an equivalent manner, fix these bases to rigid surfaces, which was impossible in the prior art with a homogeneous and identical location of the elements on both sheets. Furthermore, the invention permits a regular and homogeneous location of the clasping elements, whether they are separate or continuous, it being possible for the two wheets to be identical.

As is apparent from the foregoing, the invention is not limited to the embodiments which have been mentioned; on the contrary, it would be possible to conceive various modified constructions without departing from the scope of the invention.

Claims

What we claim is:

1. Separable fastening sheet designed to cooperate with another fastening sheet, comprising a sheet-like base member, a plurality of clasping elements attached to said base member, each said clasping element comprising a connecting portion secured to and extending outwardly from said base member and a head portion secured to the end of said connecting portion spaced outwardly from said base and said head portion extending outwardly from said connecting portion, at least a number of said head portions each having a laterally extending widened portion as compared to the end of the connecting portion to which said head having the widened portion is attached, at least a part of said widened portion comprising a flexible lip arranged to bend in a direction substantially perpendicular to said base member, whereby the flexible lip deflects with respect to the remainder of said clasping element for penetration of said head portion into locking engagement with head portions on another fastening sheet and the deflected flexible lip undergoing at least a partial return to its original undeflected rest position in its locking engagement position.

2. Fastening sheet according to claim 1, wherein the head portion of one said clasping element of one sheet is arranged in locking interengagement between at least two adjacent said clasping elements on another said fastening sheet.

3. Fastening sheet according to claim 1, wherein said sheet is arranged for locking engagement with an identical said fastening sheet.

4. Fastening sheet according to claim 1, wherein the flexible lip of said widened portion occupies at least a part of the lateral edge of said head portion.

5. Fastening sheet according to claim 1, wherein the connecting portion is a stem, and the clasping elements are separate from one another.

6. Fastening sheet according to claim 5, wherein said clasping elements are located in a regular homogeneous arrangement in lines and columns on said base member.