GB2104950A

GB2104950A - Fastening devices

Info

Publication number: GB2104950A
Application number: GB08121843A
Authority: GB
Inventors: Michael Philip Payne
Original assignee: PAYNE Ltd PHILIP
Current assignee: PAYNE Ltd PHILIP
Priority date: 1981-07-15
Filing date: 1981-07-15
Publication date: 1983-03-16
Also published as: GB2104950B

Abstract

A fastening device to fasten together a first article and an overlapping second article comprises: a bracket 10 for attachment to the first article the bracket preferably being in the form of an elongate metal strip 13 having disposed along its length a series of serrations 16 to provide detent means; a leg 11 to bear against said second article, the leg carrying a compression spring 23 or other resilient means; and an actuation member 12 mounted so as to move with respect to the leg to compress the spring, the actuation member carrying an arm 30 for releasable engagement with the detent means. <IMAGE>

Description

SPECIFICATION Fastening devices This invention relates to fastening devices, and in particular it relates to fastening devices to fasten together a first article and a second article disposed in overlapping relation to said first article. These fastening devices are of especial use in the fitting of lights or loudspeakers or like apparatus in circular or other apertures in ceilings.

Accordingly, the invention provides a fastening device to fasten together a first article and a second article disposed in overlapping relation to said first article, said device comprising: a bracket for attachment to said first article, the bracket carrying a detent means; a leg to bear against said second article the leg having resilient means associated therewith; and an actuation member adapted to move with respect to the leg to compress the resilient means, said actuation member having a catch for releasable engagement with said detent means; Whereby when the bracket is attached to said first article and the leg is brought into contact with said second article, the first and second articles can be fastened together by moving the actuation member with respect to the leg so as to compress the resilient means, and engaging the catch with the detent to hold the resilient means compressed.

The bracket is conveniently a metal or other elongate member, the detent means comprising a plurality of serrations or other stops disposed along the elongate member; for example, the stops can be ones formed by stamping on elongate metal strip so as to deform it to form a series of linearly disposed serrations. In one form of the invention an elongate metal strip comprising the bracket is formed at one end thereof with a flange by means of which the bracket can be attached to said first article.

The leg is conveniently a metal or other elongate strip which can, for instance, be of the same material as that comprising the bracket. The leg conveniently has at its lower end a pressuredistributing foot, for example in the form of a flat metal disc. The resilient means associated with the leg can be, for example, a compression spring and it is with reference to the use of a compression spring that the following description particularly relates. The compression spring, in a preferred form of the invention, is disposed as a loose sliding fit on the leg, and the leg preferably has a stop in its lower portion to retain the spring in place. Where the leg has a pressure-distributing foot the latter can provide the stop for the spring.

In the form of the invention particularly described below the actuation member is a bifurcated member adapted slidingly to move along the leg. The bifurcated member can have one arm providing said catch for the detent means and the other arm providing, with said bracket, a fulcrum about which the actuating means can rock or pivot to effect engagement and disengagement of the catch with the detent means. The sliding movement of the actuation member with respect to the leg is conveniently provided by said member having an aperture to receive the leg as a loose sliding fit. Where, for example, the actuation member is bifurcated and also takes the form of a U-shaped member, it will normally have two corresponding apertures to accommodate the leg therein.The bifurcated form of actuation member conveniently has in said other arm, that is, the arm providing with the bracket a fulcrum about which the actuation member can rock or pivot, an aperture to receive the bracket as a loose sliding fit. If this aperture is large enough it will permit the actuation member to be turned about the bracket so as to facilitate the fitting in a ceiling aperture of, for example, a loudspeaker.

There is now described, by way of example and with reference to the accompanying drawings, a clamp which is a preferred embodiment of the fastening device of the invention. In the drawings: FIGURE 1 is a side elevation of the clamp; and FIGURES 2 and 3 are respectively a side elevation and a perspective view of the clamp shown in use clamping together an annular ring to a ceiling.

The clamp comprises a bracket 10, leg 11 and an actuation member 12. The bracket 10 comprises an elongate strip 1 3 having formed at its upper end a right angled flange 14 and at its lower end a right angled flange 1 5, the purpose of which is described below. Disposed along its length the bracket has a series of serrations 1 6 providing detent means. Each of the serrations has a downwardly and outwardly inclined sioping surface 1 7 and an inwardly directed surface 1 8 disposed substantially at a right angle to the surface of the strip 1 3.

The leg 11 comprises an elongate strip 1 9 the lower end of which has a right angle flange 20 to which is attached by means of welding a foot in the form of a circular steel disc 21. The upper end of the strip has a right angle flange 22 extending from the strip in a direction opposite from that of flange 21. The leg 11 also comprises a compression spring 23 disposed between the flange 20 and the actuation member 12 and surrounding strip 1 9.

The actuation member 1 2 is a bifurcated member of a general U-shape comprising upper and lower arms 24, 25 and a connecting portion, of substantially semi-circular cross-section 26.

The arms 24, 25 in their portions adjacent connecting portion 26 have two corresponding apertures 27, 28 passing the elongate member 1 9 but sufficiently small not to pass flange 22 which acts as a stop to prevent actuation member 1 2 from becoming disengaged from the leg.

The outer portion of arm 25 of the actuation member has formed therein a rectangular aperture 29 within which is disposed the elongate strip 1 3 of the bracket 1 0. The outer extremity of arm 24 has formed therein a broad recess 30 of a width such as to accommodate elongate strip 13, and the edge of which can engage the lower surface 1 8 of any of the serrations 1 6. As illustrated in Figure 3, the lateral distance between the semicircular end of actuation member 12 and the bottom of recess 30 in relation to the distance between the semi-circular end to the outer edge of rectangular aperture 29 is such that the difference between them is substantially equal to the thickness of elongate strip 13.Thus, as is illustrated in Figure 3 when strip 1 3 is in contact with the outer edge of rectangular aperture 29 and the bottom of recess 30 is in contact with the serration-carrying surface of strip 1 3 the actuation member cannot pass over the next highest serration 1 6.

Figures 2 and 3 illustrate the use of the clamp for clamping together an annular metal strip 31 to a portion of a ceiling 32. The annular strip can, for example, be part of a means for installing a loudspeaker or light into the ceiling. For this purpose, the clamp can be installed as follows.

First, the bracket 10 is detached from actuation member 12 by sliding it through rectangular aperture 29, leaving actuation member 1 2 captive on the leg 11 as shown in Figure 1. The bracket 10 is then attached to the annular ring by sliding its flange 1 5 under the tear portion 33, the tear portion being of a size and dimensions such as to accommodate flange 1 5 as a sliding fit. Normally, for the purpose of installing the annular ring and its associated loudspeaker or lighting fitting, three, four or even more fastening devices of the invention will be required, and in that event a similar procedure will be followed for each of those devices. However, for the sake of simplicity the installation of only one of the devices is now described.

The annular ring, having attached thereto elongate strip 1 3 is then presented to an appropriately-sized circular aperture in ceiling 32, the aperture being such that there is a substantial overlap between the annular ring 31 and the ceiling (Figure 2). The assembly of leg 11 and actuation member 1 2 is then attached to bracket 10 by inserting elongate strip 13 through the rectangular aperture 29. This can be done conveniently (assuming that the assembly is being carried out from a position beneath the level of the ceiling) by initially presenting the assembly in a disposition at 1 800C from that shown in Figure 3 and then rotating it with respect to the bracket into substantially the position shown in Figure 3.If assembly is to be effected in this way the rectangular aperture 29 of the actuation member should be sufficiently large to permit said rotation.

The actuation member is then pressed downwardly against the resistance of compression spring 23 thereby forcing the catch provided by recess 30 up the inclined surface 1 7 of the first serration immediately beneath the arm 24 till the catch passes over the serration and locks beneath it against surface 1 8. Downward pressure on actuation member 1 2 is continued till compression spring 23 is compressed to the desired extent. Relaxation of the downward pressure then permits the actuation member to rise slightly and for arm 24 to be retained under the nearest serration above that arm.The catch provided by recess 30 is effective to hold actuation member 12 in place because the upward pressure exerted by compression spring 23 against the lower arm 25 tends to pivot the actuation member with respect to the edge contact between the outer edge of aperture 29 and the co-acting surface of elongate member 13.

Annular ring 31 is now clamped firmly against ceiling 32 by means of the upward force applied to bracket 10 by compression spring 23 acting through actuation member 12.

The clamp can be released as follows.

Downward pressure is applied in the region of the semi-circular portion of actuation member 12 (that is, that portion of the actuation member lying on the right hand side of the leg 11 as shown in Figure 3). This pressure serves to pivot slightly the actuation member with respect to the edge contact between aperture 29 and elongate strip 13, referred to above and thereby to disengage recess 30 from the lower surface 1 8 of the serration which has held it in place during the clamping. Arm 24 thus becomes free to ride over the serration and, so long as pressure is continued on the actuation member as described above, arm 24 is free to ride over successive serrations, under the upward pressure exerted by compression spring 23, till the clamp has been released to a desired extent. If it is desired to dismantle the clamp the assembly of the spring-loaded leg and actuation member can be rotated through 1800 about bracket 10 so as to bring the assembly over the aperture defined by annular plate 31 and permit removal of the assembly therethrough.

Claims

1. A fastening device to fasten together a first article and a second article disposed in overlapping relation to said first article, said device comprising: a bracket for attachment to said first article, the bracket carrying detent means; a leg to bear against said second article the leg having resilient means associated therewith; an actuation member adapted to move with respect to the leg to compress the resilient means, said actuation member having a catch for releasable engagement with said detent means; whereby when the bracket is attached to said first article and the leg is brought into contact with said second article, the fist and second articles can be fastened together by moving the actuation member with respect to the leg so as to compress the resilient means, and engaging the catch with the detent to hold the resilient means compressed.

2. A fastening device according to Claim 1, in which the bracket comprises an elongate member and the detent means comprises a plurality of stops disposed along the said elongate member.

3. A fastening device according to Claim 1 or 2, in which the actuation member is adapted slidingly to move along the leg.

4. A fastening device according to Claim 3, in which the actuation member is a bifurcated member one arm of which provides said catch and the other arm of which provides, with said bracket, a fulcrum about which the actuation member can rock or pivot to effect engagement and disengagement of the catch with the detent means.

5. A fastening device according to Claim 4, in which the actuation member has an aperture to receive as a loose sliding fit the leg.

6. A fastening device according to any of the preceding claims, in which the leg has at its lower end a stop, and said resilient means comprises a compression spring disposed between the actuation member and said stop.

7. A fastening device according to Claim 6, in which the leg has a pressure distributing foot which constitutes said stop.

8. A fastening device according to any of Claims 4-7, in which said other arm has formed therein an aperture to receive the bracket as a loose sliding fit.

9. A fastening device according to Claim 8, in which said aperture is large enough to permit the actuation member to be turned about the bracket.

10. A fastening device according to Claim 1, substantially as described with reference to the accompanying drawings.

11. A fastening device to fasten together a first article and a second article disposed in overlapping relation to said first article, substantially as shown in the accompanying drawings.