GB2259324A - Improvements in and relating to releasable fastening means - Google Patents

Abstract

A releasable fastening device for use in supporting an article from a ladder or the like comprises a formed wire spring shaped to form a supporting hook (1) and a pair of angled limbs (2) which terminate in outwardly angled elbows (3). The elbows (3) are compressible towards one another in the horizontal direction and the angled portion of the limbs (2) are compressible towards one another in the vertical direction to provide for secure frictional engagement of the device in the open end of a ladder rung. The open end of the hook 11 may optionally be closed by means of a latch (8) also of formed wire and pivoted about fulcrums (7). The angled portions of the limbs (2) also enable the device to be used in an alternative manner as a belt hook. <IMAGE>

Description

Improvements in and relating to releasable fastening means This invention concerns improvements in and relating to releasable fastening means, and more especially to such a means for securing an implement for use by a workman to a ladder or the like. One embodiment of the device may also serve the additional function of a belt hook.

Various devices have hitherto been proposed for use by a workman to hold tools or other articles required for use whilst standing on a ladder. It is common, for example to attach a paint tin to a rung of a ladder by means of an S-hook. Hitherto known devices however, either are relatively complicated or do not support the article in a convenient position.

It is accordingly an object of the invention to provide an improved device.

The invention is based on the concept of using the open end of a ladder rung that is generally present in a modern ladder of metal construction as a socket into which to plug a releasable fastening device to which can be attached, or upon which can be supported, an article required for use.

Thus according to one embodiment of the invention there is provided a releasable fastening device comprising an end portion adapted to act as a spigot for insertion into the open end of a ladder rung, there being attached to the spigot a support for receiving an article to be held on the ladder.

Conveniently the support is in the form of a hook, and the device is formed from spring wire bent to an appropriate configuration, or from a material that is similarly resiliently deformable.

Further preferred features and advantages of the invention will become apparent from the following description and the appended claims.

The invention is illustrated by way of example in the accompanying drawings, in which: Fig. 1. is a perspective view of various known configurations of extruded tubing from which conventional rungs of a metal ladder are formed, Fig. 2. is a side elevation of one embodiment of device in accordance with the invention, and Fig. 3. is a plan view of the device of Fig 2.

Referring to Figs 2 and 3 of the drawings there is shown one embodiment of the invention, which comprises a portion of spring wire bent double to form a loop 1 from which extend a pair of limbs 2. The loop 1 forms a hook from which can be hung any appropriate implement, such as the handle of a paint tin, and the two limbs are bent to form elbows 3, the ends of which are angled outwardly by bending of the limbs at 4. Free ends 5 of the limbs that extend back towards the loop 1 from the elbows 3 are again angled outwardly and upwardly at 6 and terminate in end portions 7 that are bent laterally outwards substantially at right angles. The end portions 7 are coaxial and form a fulcrum about which can pivot a stirrup 8 which is formed from spring wire of smaller gauge and serves as a safety clip for closing the open end of the hook 1.

Referring to Fig 1 there are shown the conventional shapes of extrusion commonly used for the rungs of a metal ladder. The upper portion 9 of the extrusion that is to form the tread portion of the rung is flat and thus in each case the extruded section has longitudinally extending internal upper corners 10. The lower part of the extrusion is either generally rounded or may be symmetrical with the upper portion.The illustrated configuration of the device of Figs 2 and 3 is thus such that it can provide a firm frictional fit into any of the available extruded sections, since the outwardly turned elbow portions 3 will make snug engagement at their extremities into the upper corners 10 of the extruded section, whilst the lower portions of the limbs extending towards the hook 1 will be forced towards one another at the points 4 so that they make contact both with one another and with the middle of the base wall 11 of the extrusion.

The action of insertion of the device into any one of the extruded sections causes a complex stressing of the spring wire in several directions. Thus, upon insertion of the elbows 3 into the open end of a metal rung they are forced towards one another by the side walls of the extruded section, initially bending the wire loop 1 under relatively light pressure until the points 4 come into contact with one another to provide greater resistance to bending.

As the points 4 make contact, further inward bending of the elbows about the points 4 tends to spread apart the free ends 7 that extend back beyond the points 4, before they become fully inserted into the rung. Further insertion of the limbs 2 now compresses the two ends 7 towards one another, exerting a force of torsion upon the elbows 3 that in turn leads to the application of a leverage about the points 4 to increase the outward spring force upon the elbows 3 and thus to increase the frictional lock between the latter and the internal surface of the extruded section. At the same time the ends 7 and the limbs 2 are compressed vertically to fit the dimension of the available aperture.Since the lower edges of the points 4 now rest adjacent the open edge of the aperture, the latter forms a fulcrum such that the weight of an implement placed upon the hook 1 applies an upward leverage upon the elbows 3 thus further increasing the frictional forces between the latter and the extruded section. It will be noted that the limbs 2 are angled at 12 and 13 to reduce the angle of contact with the mouth of an aperture into which the device is inserted, thus reducing any tendency of the device to slip out of the aperture due to its spring action or to loads placed thereon.The device is designed to fit apertures of a range of sizes such that, depending upon the dimension of the aperture, the portions of the limbs between the angled points 12 and 13 and the mouth of the aperture either lie generally parallel to the internal wall of the extruded section or are forced away therefrom by pressure upon the angled portions 12 and 13.

Thus not only does the device according to the invention provide a secure attachment to the ladder but also the fact that it extends laterally therefrom enables any device supported therefrom to be presented in a convenient position for access from the ladder, which is not the case with devices that require to be hung from a rung between the rails of the ladder.

The device illustrated is also versatile in use, since the angle formed by the elbows 3 can serve as a hook to enable the device to be supported from a belt worn by the user, when not required for use upon a ladder.

It will be appreciated that other uses may occur for a device incorporating the spring action described in respect of the spigot and socket connection, and thus the device is not to be regarded as exclusively for use with a ladder. For example it could be inserted into the open end of a scaffold pole. Furthermore the hook portion of the device may be replaced with any other connecting means appropriate for the use contemplated.

Claims (9)

1. A releasable fastening device comprising a spigot of resiliently deformable material adapted for insertion in the open end of a ladder rung.

2. A device according to Claim 1, wherein said spigot comprises a pair of limbs each of which is angled to form an elbow, said limbs extending longitudinally away from one another from a resilient root portion connecting said limbs to the respective elbows, and the arrangement being such that the spigot can be compressed with reference to a first transverse axis to cause said elbows to approach one another, with resilient flexing of said root portion, and can be compressed with reference to a second transverse axis to cause angled portions of said limbs to approach one another with resilient flexing of said elbows.

3. A device according to Claim 2, wherein the said elbows are angled outwardly away from one another, whereby the major dimension of the spigot in the direction of said first transverse axis occurs at the extremities of said elbows.

4. A device according to Claim 2 or 3, wherein the said resilient root portion comprises a loop of material formed to the shape of a hook.

5. A device according to any one of Claims 2-4, wherein free ends of angled portions of said limbs remote from said root portion are angled outwards to form stops for limiting insertion of said spigot into a ladder rung.

6. A device according to Claims 4 and 5, wherein the outwardly angled free ends of said angled portions form a fulcrum supporting a pivotable catch for engagement with a free end of the loop to close the opening of said hook.

7. A device according to any one of Claims 2-6, consisting of a formed wire spring.

8. A device according to Claim 7, wherein the wire forming each angled portion of each limb is further bent to reduce the transverse distances between the compressible portions of the spigot in the region of the said free ends of the limbs and thus to reduce the angle of contact with the said open end of the ladder rung.

9. A releasable fastening device substantially as described herein with reference to the accompanying drawings.