GB2121095A

GB2121095A - Tie fastener

Info

Publication number: GB2121095A
Application number: GB08216361A
Authority: GB
Inventors: George Charles Baird
Original assignee: United Wire Group Ltd
Current assignee: United Wire Group Ltd
Priority date: 1982-06-04
Filing date: 1982-06-04
Publication date: 1983-12-14
Also published as: NO832018L

Abstract

A fastener for a tie, strapping or the like, has a body (10) with a through bore (15) in which is a wedging member (20). The tie (19) is fixed at one end to the body, and at the other end passes around the wedging member so that, when the tie is tensioned, the wedging member is drawn in the bore into wedging engagement therewith to secure said other end portion of the tie. The member (20) has a hole (21) to receive a shear pin to hold the member (20) out of wedging engagement with the bore (15) until tension is applied to the tie (19). <IMAGE>

Description

SPECIFICATION Tie fastener This invention relates to a fastener for ties, i.e.

to a fastener to enable a tie to be secured under tension around one or more articles.

It is well known to secure together two or more articles by passing a tie around the articles and fastening it under tension to hold the articles together. We have now devised a fastener for this purpose which can be used with any length of tie, as desired by the operator on site, and which is particularly (though not exclusively) useful for subsea operations by divers.

According to the invention, there is provided a fastener for ties, which comprises a body formed with a bore, means for attaching the body to one end portion of a length of tie, and a wedging member which is wedgable in said bore, and wherein the other end portion of the length tie can be looped around the wedging member so that, when tension is applied to the tie, the wedging member is drawn thereby in the bore to wedge the said other end portion of the tie in the bore.

In use of the fasteners of the invention, there is a wedging action between the bore and the wedging means. For this purpose, either the wedging means may taper, or the bore may taper, or both may be tapered (or otherwise shaped to provide the wedging action).

One preferred fastener of the invention comprises a body formed with a through bore of reducing size; means for attaching the body to one end portion of a length of tie, wedging member slidable in a portion of the bore; and releasable locating means to hold the wedging member in said portion of the bore; wherein, when said wedging member is so held, the other end portion of the tie can be passed into the bore and looped around the wedging member, and wherein when tension is applied to said tie and the locating member released, the wedging means is drawn by said tie to move into a narrower portion of the bore and so wedge the tie between the wedging member and the bore to fasten said tie.

The locating means serves initially to hold the wedging member in such a position in the bore as to enable loading with the end portion of the tie.

Once loading is achieved, tension may be applied to the tie to tighten it around the articles being secured. When the desired tension is achieved, the locating means can be released (whilst the tie tension is maintained), whereupon the wedging means is drawn by the tensioned tie in the bore to wedge the tie firmly therein. The tension in the tie keeps the wedging member firmly wedged in the bore, and so keeps the fastening secure.

The locating means can be in a variety of forms such as, for example, a locking pin passing through the body and engaging the wedging means. The locking pin can be disengaged, e.g.

withdrawn, manually or can for example be spring-loaded or otherwise arranged to release the wedging means by remote control at the desired moment. In one preferred embodiment of the invention, the locating means comprises on or more shear pins which automatically shear to allow the wedging member to slide into the wedged position when the tie tension reaches a predetermined level. This arrangement has a number of important advantages. Firstly, for certain purposes, it can be important to ensure that the tie is not over-tensioned, e.g. either to avoid breakage of the tie itself or damage to the article(s) being secured. Secondly, and particularly for sub-sea uses, the automatic release of the wedging means when the predetermined tension is achieved, greatly simplifies the fastening operation and relieves the user (e.g. diver) of difficult and time-consuming operations.

Automatic release of the locating means can be achieved other than with shear pins, for example by providing a localised narrowing of the bore which will hold the wedging member only until the predetermined tension is reached.

Whilst it is not essential, we prefer that the cross-sectional shape of the bore and of the wedging member be substantially the same, and in one preferred embodiment both are rectangular in cross-section. In loading the tie around the wedging member, we prefer the tie to enter through one end of the bore, pass along one side and around the further end of the wedging means, and return along the other side and exit from the said one end of the bore. This arrangement provides an excellent wedging effect in use. It is not essential for the tie to be looped in exactly this path, provided that it is firmly secured when the wedging means is pulled by the tensioned tie into the wedging position in the bore.

The body of the fastener of the invention also includes means for attaching it to the other end of the length of tie in use. Suitably, such means may comprise a series of slots in the body, through which the tie can be looped. Other attachment means can be used. Most preferably, however, the attachment means are such that the tie can be fixed to the fastener body simply and on site, so that the correct length of tie can then be selected and the other end secured by the wedge action in the bore.

When a tie is secured under tension about an article, that end portion of the tie wedged in the bore will be essentially non-releasable until the tension in the tie is sufficiently relieved to allow the wedging means to slide in the bore to release the wedge. Where, therefore, it is wished to provide for release of the tie without severing it, the attachment means on the fastener should be such as to allow such release.

We prefer to make the fastener body as a onepiece plastics moulding (although, of course, it can be made of other materials, including metals).

Plastics mouldings are preferred for subsea purposes (to avoid corrosion) and are also relatively cheap to manufacture. The wedging member will also normally be of the same plastics material, although of course it must be compatible with the material of the body in order to achieve the desired wedging action in use.

The nature of the tie may vary widely, and ties of circular or oval cross-section (e.g. cords) can be used as well as essentially flat ties (e.g. strapping).

The fasteners of the invention are very suitable for use with high-strength plastics strapping, e.g.

extruded polyester band such as "Tenax". The thickness of the tie must not, of course, be so great that the tie cannot be drawn fairly readily around the wedging member in the bore during loading.

In the method of using a fastener of the invention, the body is first attached to one end portion of the tie. The appropriate length of tie (cut on site from a continuous reel, for example) is then passed around the article to be secured and the free end portion passed into the bore, around the wedging means and back out of the bore. The free end of the tie is then drawn through the fastener (sliding in the bore around the wedging means) until the desired tension is achieved and the locating means (if present) released to allow the wedging means to slide into a wedging position and fasten the tie.

In order that the invention may be more fully understood, one embodiment of fastener of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein: FIGURE 1 is a top plan view of the fastener; FIGURE 2 is a side elevation; FIGURE 3 is a front end elevation omitting the wedging member; FIGURE 4 is a vertical section on the line 4-4 of Figure 1, the wedging member and strapping being shown in phantom; and FIGURE 5 is a side elevation of the wedging member.

In the Figures, like numerals indicate like parts.

The body 10 of the fastener comprises a unitary plastics moulding having a base 11, a pair of side walls 12, 13 and a top 14, all defining a through bore 1 5 extending from the front 1 6 to the rear 17 of the fastener. At the forward end of base 11 are three slots 1 8 for attaching the fastener to one end of strapping 1 9 (dashed lines in Figure 4). By looping the strapping as shown in Figure 4, it will be held firmly by the slots 18. The bore 1 5, which is of rectangular cross-section, tapers towards the rear end 17 of the body, and a wedging member 20 (dashed lines in Figure 4) is slidable in the front end of the bore, but wedges in the rear end. The side walls 12, 13 are each formed with an aperture 21 through which a locking pin or shear pin (not shown) can be inserted.The wedging member has a corresponding lateral bore 22 to receive the locking pin, whereby the wedging member can be retained in the wider front end of the bore for loading the strapping (Figure 4).

As shown in Figure 4, the strapping 1 9 is passed into the bore 1 5 at the rear end of the fastener body, passes around the wedging member 20 and exits from the bore 1 5 at the narrower end of the body. When tension is applied to the strapping 19, and the locking or other pin removed or sheared, the wedging member 20 is drawn to the left (Figure 4) to wedge in the narrower rear end portion of the bore 15, with the strapping firmly held between the wedge means and the base 11 and top 14 of the fastener bore.

As drawn, the base 11 of the fastener is slightly concave (Figure 2), to assist in its use on curved surfaces.

If desired, either the wedging means, or the walls of the bore, or both, may be roughened or otherwise provided with a surface to improve the wedging grip. The wedging means itself may be of wedge-like shape to improve the wedging action, i.e. in the illustrated embodiment the rearward end 30 of the wedge could be of smaller cross-section than the forward end 31.

Claims

1. A fastener for ties, strapping or the like, which comprises a body formed with a through bore, means for attaching the body to one end portion of a length of tie, and a wedging member which is wedgable in said bore, and wherein the other end portion of the length of tie can be looped around the wedging member so that, when tension is applied to the tie, the wedging member is drawn thereby in the bore to wedge the said other end portion of the tie in the bore.

2. A fastener according to claim 1 , wherein the bore is tapered.

3. A fastener according to claim 1 or 2, wherein the wedging member is tapered.

4. A fastener according to claim 1, 2 or 3 wherein the bore and the wedging member are closely similar in cross-section.

5. A fastener according to any of claims 1 to 4 which also comprises releasable locating means for maintaining the wedging member out of wedging engagement with the bore until said locating means are released.

6. A fastener according to claim 5, wherein said locating means comprises one or more pins.

7. A fastener according to claim 6, wherein at least one pin extends from said body into said wedging member.

8. A fastener according to claim 6 or 7, wherein said pins are shear pins which automatically release said wedging member when the tie is tensioned.

9. A fastener according to claim 5, wherein said releasable locating means comprises a construction in said bore.

10. A fastener according to any preceding claim, wherein said attaching means comprises two or more slots formed in said body, through which said one end portion of the tie may be secured.

11. A fastener according to any preceding claim, wherein said body is a one-piece plastics moulding.

12. A fastener according to any preceding claim, wherein said wedging member is a onepiece plastics moulding.

13. A fastener for ties, strapping or the like substantially as herein described with reference to the accompanying drawings.

14. A method of securing a tie around one or more articles, which comprises securing one end portion of the tie to a fastener as claimed in any preceding claim, passing the other end portion of the tie around the said wedging member of the fastener, and tensioning the tie around the article(s) to draw the wedging member in the bore to wedge the said other end of the portion of the tie in the bore.