GB2099907A

GB2099907A - U-shaped metal clips

Info

Publication number: GB2099907A
Application number: GB8210677A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-05-09
Filing date: 1982-04-13
Publication date: 1982-12-15
Also published as: ES273588U; DE3118415C2; DE3118415A1; GB2099907B; FR2505419A1; FR2505419B1; IT1210882B; IT8221126A0; ES273588Y

Abstract

A resilient metal U-clip having limbs (2, 3) connected by a web (1) to grip a plate or strip (7) has the limb ends (4, 5) bent over at right angles. The ends (4, 5) are punched to form lugs (6) having their ends (8) bent over to form edges (9) which engage the plate or strip surface. The lugs lie at an angle ??? to the limb ends to give a self locking action which serves to increase the gripping force when the clip is pulled away from the plate or strip edge. <IMAGE>

Description

SPECIFICATION U-shaped metal clips This invention relates to U-shaped metal clips for fastening components onto retaining flanges; the term "retaining flange" should be taken quite generally as being the edge strip of a supporting plate.

Such a metal clip comprises a web and two clamping limbs, which engage around and resiliently grip the flange between them; lugs which engage the flange underthe gripping force and which have edges bent away from the flange are joined to at least one ofthe clamping limbs, in such a way that the lugs bend obliquely toward the web in the opposite direction to the fitting-on movement of the clip.

Metal clips of this type are known e.g. from Patent Specification No. 780 445. Their chief purpose is to fix structural or operating components onto a supporting plate so that they are difficult to release. The components are accordingly usually provided with a corresponding flange or edge strip, and the clip surrounds this together with the retaining flange and clamps it in. However, the metal clips may equally well be used as a fastening base for other retaining elements, such as cable grips, in this case the clip portion is moulded directly onto the retaining portion and combined to form one part, or alternatively they are equipped with additional retaining shoulders or the like and used e.g. in vehicle construction, for fastening mouldings onto projecting edges of the body.

In all these applications the clamping force is generated by the resilience ofthe clamping limbs and clamping lugs, the clamping edges of which are pushed over the retaining flange. The clamping force created by the opening movement may cause the clamping edges to penetrate varying distances into the surface of the retaining flange and make visible scratch marks. This effect is a disadvantage particularly with enamelled or otherwise surface-treated sheet metal parts, since the scratch marks encourage surface corrosion and thus form the starting point for undesirable rusting.

According to the invention, there is provided a U-shaped metal clip for fixing components to a retaining flange or the edge strip of a supporting plate, comprising a web and two clamping limbs which grip the surfaces of the flange or plate and which can be sprung wider apart, wherein lugs having clamping edges to engage the surface ofthe flange or plate are contiguously joined to at least one of the clamping limbs, so that the lugs resiliently bend towards the web when the clip is fitted on the flange or plate, wherein the lugs extend from the end ofthe clamping limb which is bent substantially at right angles from the main body of the limb and at a distance from the limb main body such that when the lugs are in the clamping position they are inclined to the limb end at such an angle that they lock the clip to the flange or plate.

With the clips constructed in accordance with the invention, the clamping edges of the lugs can be pushed over the flange of the supporting plate without exerting any great pressure on it, since the lugs need far less bending resistance than the limbs. In the clamping position, on the other hand, the selflocking effect causes the lugs to act as a rigid support between the limbs and the retaining flange, so that the clamping force is determined substantially by the bending resistance of the limbs and connecting web. When pulling forces are applied, the clamping force is yet further increased; this is because with the self-locking effect the clamping lugs tend to move from their slightly backwardly inclined position into a perpendicular one and to press the limbs outwards, so that the limbs exert an increased clamping force.For fitting on purposes therefore only the bending resistance of the join between the lugs and the limbs need be overcome, whereas for securing purposes the lugs act as supports and the bending resistance of the whole clip, i.e. of both limbs and the web, comes into action.

Further, the lugs will bend readily if they are only half as wide at their joints with the limbs as they are at the clamping edge. For the purpose ofthe clip action it is also advantageous for the end part of each lug which is bent away at the clamping edge to project from the main part of the lug approximately at right angles; this makes it impossible for the lug to swing past the limb at the joint.

Embodiments of the invention are illustrated in the accompanying drawings and will be explained in greater detail below. In the drawings: Fig. 1 is a side elevation of a U-clip according to the invention, Fig. 2 is a front elevation of the clip, Fig. 3 shows the clip on a larger scale with the mode of operation of its clamping lugs (a) before being fitted onto a retaining flange, (b) after being fitted, and (c) when being pulled off the retaining flange, Fig. 4 shows an embodiment of the invention forming a cable clamp, Fig. 5 shows a further embodiment forming a trim strip clip for edge protection, and Fig. 6 shows another embodiment for fixing trim strips in the opening of a vehicle windscreen.

The metal clip illustrated in the drawings comprises a web 1 and two clamping limbs 2 and 3 which can be sprung wider apart. The limbs are bent outwardly at right angles at their ends 4 and 5. Two clamping lugs 6 are punched out of each of the ends 4 and 5 and out of part of the main bodies of the lambs 2 and 3, and they are biassed resiliently towards the web 1. The free ends 8 of the clamping lugs 6 are bent back approximately at right angles towards the web and have rounded gripping edges 9 which, when the clip is in use, lie against the retaining flange 7 (Fig. 3b).

The main parts ofthe clamping lugs 6 lie substantially perpendicular to the main bodies of the limbs 2 and 3 or are inclined slightly towards the web. They are joined to the edges of the ends 4 and 5, approximately at 10. There is a relatively small cross-section of metal at the joint, so the lugs 6 can bend resiliently substantially at the joint, because of the reduced bending resistance there. As indicated in Figure 2, this reduced cross section can easily be achieved by making the lugs 6 only half as wide as the joints 10 as they are at their free ends 8.

The joint 10 between the lugs 6 and the ends 4 and 5 is provided at a distance a from the planes of the main bodies of the limbs 2 and 3, such that when they are in the clamping position the main parts of the lugs 6 lie at an angle ato the ends 4, 5 and the ends 8 lie at substantially the same angle to the surfaces ofthe flange 7, which angle, having regard to the frictional resistance between the gripping edge 9 and the retaining flange 7 comes within a selflocking range. With a lacquered surface the angle a should not be more than 80.

Figures 3(a)-(c) demonstrate the mode of operation of the self-locking lugs 6.

Figure 3(a) shows the metal clip in the unstressed state, i.e. before being fitted onto the retaining flange 7. Here the lugs 6 are for manufacturing reasons inclined only slightly towards the web, and the distance/ between the opposed gripping edges 9 is somewhat smaller than the thickness d of the retaining flange 7.

Figure 3(b) shows the lugs 6 bent backwards when the clip has been pushed onto the flange. The edges 9 of the lugs meetthe flange 7 at an angle cur of less than 8 . As a result ofthe sharp angle aand the frictional resistance there is a self-locking effect, which allows the clip to move readily only in the direction of the arrow A but not in the opposite direction B.

Figure 3(c) indicates how the lugs 6 move into a vertical position relative to the flange and how the limbs 3 open out by an amounts by means of the ends 8, when a strong pulling force is exerted in direction B. With this bending effect the clamping force exerted by the limbs 2, 3 through the lugs 6, necessarily increases. The free ends 8 prevent the lugs 6 from being rotated further relative to the ends 4,5 atthejoint 10.

Figures 4 to 6 illustrate modifications of the basic clip.

Figure 4 shows a cable grip with a clamping yoke 11 extending from the end 5 ofthe clamping limb 3.

In this example the lower clamping limb 2 has no lug 6. However, these may be added, should they prove necessary to apply the clamping force.

Figure 5 shows how an edge protecting profile 12 with a trim strip clip provided with clamping lugs 6 arranged in accordance with the invention can be fitted and fixed onto an edge of a car body, in the form of a flange 7, so that the enamel is protected.

In Figure 6, a moulding clip fixed on aT-bolt 16 is provided with clamping lugs 6 according to the invention, in order to fix a moulding 13 with a retaining flange 7 in the opening 14 for a windscreen 15. In this case the purpose is not so much to protect the enamel as to facilitate the mounting of the moulding 13 as compared with the conventional claw fastening method. The head 17 of the T-bolt 16 still increases the clamping action, since the U-clip as an entity can no longer spring open but only the part of the limb 3 projecting beyond the head 17 of the T-bolt.

Claims

1. A U-shaped metal clipforfixing components to a retaining flange or the edge strip of a supporting plate, comprising a web and two clamping limbs which grip the surface of the flange or plate and which can be sprung wider apart, wherein lugs having clamping edges to engage the surface of the flange or plate are contiguously joined to at least one of the clamping limbs, so that the lugs resiliently bend towards the web when the clip is fitted on the flange or plate, wherein the lugs extend from the end of the clamping limb which is bent substantially at right angles from the main body of the limb and at a distance from the limb main body such that when the lugs are in the clamping position they are inclined to the limb end at such an angle that they lock the clip to the flange or plate.

2. A clip according to claim 1, wherein the width of each clamping lug at its joint with the limb is half the width at the free end of the lug.

3. A clip according to claim 1 or 2, wherein each clamping lug is punched out of the metal of the limb.

4. A clip according to any of claims 1 to 3, wherein the free end of each lug is bent substantially at right angles to the main part of the lug to form its clamping edge.

5. A U-shaped metal clip for fixing components to a retaining flange or the edge strip of a supporting plate constructed and arranged substantially as hereinbefore described and shown in Figs. 1-3, 4, 5, or 6 of the accompanying drawings.