GB2289217A - Security mounting for pictures - Google Patents

Abstract

A security mounting for supporting pictures on a wall, on a screw 19 screwed into the wall and projecting therefrom, comprises a bridge-like plate 14 secured to the back of the picture and a slide member 24 (Fig. 6) which is a sliding fit in the passage defined by the plate 14 under the raised central web 16 of plate 14. The central web 16 has a hole 15 to receive the head of screw 9 while the slide member 24 has a slot with a wider portion 30a wide enough for the screw head to pass through and a narrower portion 30b which is only wide enough for the screw shank to pass through. The picture is mounted by arranging the slide member 24 so that the wider part 30a of the slot is in register with hole 15 and presenting the picture to the wall so that the screw head and adjoining part of the shank pass through the hole 15 and slot portion 30a, then sliding slide member 24 to a second position in which the slot portion 30a is moved out of register with hole 15 and the screw shank and slot portion 30b is in register with hole 15 and is extended around the screw shank so that the picture is held captive on the screw. Integral catch means holds the slide member 24 in its second, locking position. <IMAGE>

Description

PATENTS ACT 1977 DESCRIPTION OF INVENTION Title: "Security mounting for pictures, wall plaques and the like" THIS INVENTION relates to a security mounting for pictures, wall plaques and the like.

There is an increasing instance in theft of framed pictures, wall plaques and the like from the walls in hotel rooms, public houses and other public access buildings. In the past, such pictures, wall plaques and the like have simply been hooked on to mounting hooks or nails driven into the wall in which they are mounted or have been suspended from a picture rail secured to a wall, and in any event in such a manner that the picture or wall plaque can be readily removed simply by lifting it from the mounting hook or hooks or other attachments by which it is hung on the wall. Accordingly, theft of such items is relatively easy.

It is an object of the present invention to provide a mounting for framed pictures, wall plaques and the like, which still allow such items to be mounted on or removed from walls by legitimate personnel employing a special tool but which therefore makes such removal difficult for the casual or opportunist thief.

According to the invention there is provided a mounting suitable for supporting on a wall a picture, wall plaque or the like, and for providing security against theft, said mounting comprising a plate having an aperture therethrough to receive a screw head, and a slide member mounted for sliding relative to said plate in a direction generally parallel therewith, said slide member in one position thereof leaving said aperture relatively unobstructed to allow free passage of a screw head and adjoining part of the screw shank, and in another position partly occluding said aperture whilst leaving a relatively enlarged space behind said plate and said slide to accommodate a screw head, whereby with said slide in said one position, said mounting can be fitted over the head of a screw protruding from a wall and said slide moved to said second position thereof to hold the screw head captive in the mounting.

Whilst there have been various proposals for security mountings to make such theft as mentioned above more difficult, these have had various disadvantages, for example in that they have been expensive to manufacture and/or difficult to fit and operate. Another significant disadvantage of known security mountings has been that they required a screw or other fixture of a specific form and size, and which was less suited to some wall constructions than others, for example which would work with woodpanelled or brick walls but not with plasterboard walls.

It is an object of a preferred embodiment of the invention to provide a security mounting which avoids these disadvantages and can be used with a wide range of commercially available screws and other fixtures.

An embodiment of the invention is described below by way of example with reference to the accompanying drawings in which: FIGURE 1 is a schematic perspective view showing a picture frame, having security mountings embodying the invention on its rear surface, the figure showing also a part of a wall surface with a pair of mounting screws extending therefrom to receive a picture frame, FIGURE 2 is a partial rear elevation view of the frame showing one security mounting with the slide member in a first position thereof, FIGURE 3 is a view in section along the line III III in Figure 2, in said first position thereof, showing the security mounting fitting over a screw head protruding from a wall, FIGURE 4 is an elevation view corresponding to Figure 2 but showing the security mounting with the slide member in a second position thereof, FIGURE 5 is a sectional view similar to Figure 3 but along the line V-V in Figure 4 and thus showing the security mounting in said second position thereof, and FIGURE 6 is a perspective view from below of a slide member forming part of the security mounting.

Referring to the drawings, Figure 1 shows the back of a picture frame 10 to the rear surface of which are fixed, adjacent the vertical edges (in the example shown) respective mountings 12. Each mounting 12 comprises, as shown in Figures 2 to 5, a first plate 14 which is formed by bending a sheet metal blank about transverse lines lying in its plane so that it assumes the cross-sectional shape best shown in Figures 3 and 5, comprising a flat central web 16, parallel side walls 18 perpendicular to web 16 and flanges 20 extending in opposite directions away from one another, from the side walls 18. The mountings 12 are secured to the back of the picture frame with the flanges 20 against the surface of the back of the frame and with the web 16 spaced from the back surface of the frame to define therewith a slot of rectangular section.Each slot accommodates a respective slide member 24 which, in the embodiment shown, is also formed of sheet metal and is of generally U-shaped cross section comprising a flat base 26 and generally parallel side walls 28 extending perpendicularly from the base. At one end of the slide member 24, the sheet metal is turned down to form an end wall 27 perpendicular to the side walls and to the base 26.

The end wall 27 projects slightly beyond the side walls 28 to form stops for limiting sliding movement of the member 24.

Each member 24 has a longitudinal slot 30 extending therethrough along a median line mid-way between and parallel with side walls. The slot 30 is open at the end of the base 24 remote from the end wall 27 and is closed at its end adjacent wall 27. Furthermore, the slot 30 comprises a relatively wide portion 30a adjacent said open end and a relatively narrow portion 30b extending to said closed end. If desired, the slot 30 may be closed at both ends.

As shown in Figures 3 and 5, each slide member 24 is fitted into the respective slot defined between the rear surface of the picture frame and the web 16 of the respective plate 14 so that the base 26 lies against the surface of the web 16 which faces towards the rear surface of the frame, with the side walls 28 cooperating with the respective side walls 18 of the plate 14. The depth of the side walls 28 measured perpendicular to the planes of web 16 and base 26 is such that each slide member is a close sliding fit between the back surface of the frame and the opposing surface of the web 16 of the respective plate 14.

Accordingly, each plate 24 can be slid longitudinally in the respective plate 14 between the position illustrated in Figure 2 and the position illustrated in Figure 4. The web 16 of each plate 14 has a central circular aperture 15 therethrough of a diameter equal to the width of the wider part 30a of the slot.

In the position shown in Figures 2 and 3, the wider part 30a of the slot 30 is in register with the aperture 15 and accordingly the head of a screw 19 can be passed through the aperture 15 and through the registering portion 3Oa of the slot so that the screw head lies in the space defined between the rear surface of the picture frame and the surface, facing said rear surface, of the part 26 of the slide member 24. If the slide member is then slid to the position shown in Figures 4 and 5, the wider part 30 of the slot is moved from the region of the aperture 15 and the narrower part 30b of the slot moves into the region of the aperture 15 around the shank of the screw. With the slide member 24 in this position, the screw cannot be withdrawn from the mounting, since the screw head is of too great a diameter to pass through the narrower part 3Ob of the slot and the boundary of the aperture 15 prevents the screw from moving into the wider part 30a of the slot from which the screw head could be withdrawn.

In use of the mountings, in the arrangement shown, the mountings are secured to the back of a picture frame, as described above, by screws 33 extended through slots 35 in the flanges 20, which slots 35 are elongate in a direction perpendicular to the side walls 18 and thus perpendicular to the direction of sliding of the slide member. The slots 35 in the flanges have a width corresponding substantially to the shank diameter of the screws 33. The provision of elongate slots 35 to receive the screws instead of circular holes allows adjustment of the position of the mountings in the direction of elongation of the slots, for fine adjustment of the positions of the mountings on the back of the picture frame, such as may be necessary to ensure that, when in place, the upper and lower edges of the picture will be level.This feature avoids the need for strict accuracy locating the screws in the wall and in locating the screws in the picture frame in the first place.

In each slide member 24, each side wall 28 is separated from the base 26 over a part of the length of the side wall by a cut or slit extending to the free end of member 24 remote from end wall 27 to form a leaf spring which bears resiliently against the inner surface of the respective side wall 18 to hold the slide member in place without rattling. Each such leaf spring is kinked as indicated at 80 to provide a projection or detent which snaps into place behind the respective end of the respective side wall of plate 14 when the slide member 24 is pushed fully home into the respective plate 14, as shown in Figure 4.

The function of the end wall 27 of the slide member 24 is to act as a stop and to provide an abutment for a tool used to push the slide member into the position shown in Figures 4 and 5 and to conceal from the view of would-be thieves or meddlesome persons, the nature of the mechanism by which the picture is retained.

The procedure for mounting a picture fitted with the security mountings described is straightforward.

Firstly two mounting screws 19 are screwed into a wall or a wall-mounted mounting rail or the like at positions corresponding to the spacing between the two mountings. A simple template may be used to determine the correct screw positions. The screws a~e driven in until their heads project only slightly from the surface into which they are screwed. With the slide members 24 of both mounting plates in the positions shown in Figures 2 and 3, the picture is now offered up to the screws 19 driven into the wall so that the screw heads enter the apertures 15 of the plates 14.The slide members 24 are finally slid longitudinally into the positions shown in Figures 4 and 5 by means of the tool referred to inserted between the picture frame and the wall so that the picture cannot readily be removed without, firstly, a knowledge of the nature of the mounting and secondly a suitable tool capable of being inserted between the picture and wall and having a hook or the like capable of engagement with the end of the slide member remote from the end wall 27.

Whilst, in principle, different sizes of mounting may be provided for use with different sizes of picture mounting screws, it has been found that the relationship between the head diameter and adjacent shank diameter of a wide range of commercially available screws is such that it is possible to make the aperture 15 and the wider slot part 3Oa of a size to receive a wide range of screw heads and the slot part 30b of such a width to accommodate the corresponding screw shanks without allowing passage of these screw heads, so that the mounting themselves are fairly adaptable.

Thus, the security mounting described with reference to the drawings may be used with woodscrews, screws driven into plugs inserted in bores in masonry walls, screws cooperating with expanding plugs or the like specially adapted for fixing to plasterboard walls or surfaces panelled with hardboard and so on.

Claims (5)

1. A mounting suitable for supporting on a wall a picture, wall plaque or the like, and for providing security against theft, said mounting comprising a plate having an aperture therethrough to receive a screw thread, and a slide member mounted for sliding relative to said plate in a direction generally parallel therewith, said slide member in one position thereof leaving said aperture relatively unobstructed to allow free passage of a screw head and adjoining part of the screw shank, and in another position partly occluding said aperture whilst leaving a relatively enlarged space behind said plate and said slide to accommodate a screw head, whereby with said slide in said one position, said mounting can be fitted over the head of a screw protruding from a wall and said slide moved to said second position thereof to hold the screw head captive in the mounting.

2. A mounting according to claim 1 wherein said aperture is substantially circular and is centred on an axis of said plate and said slide member comprises a slide plate lying adjacent the first-mentioned plate and slidable longitudinally along said axis, said slide plate having an elongate slot therein extending diametrally with respect to said aperture parallel with the direction of sliding of the slide plate, said slot having a wider portion corresponding substantially in width to the diameter of said aperture, and a narrower portion, said wider portion being in register with said aperture in said first position when the slide member is in said one position and said narrower portion being in register with said aperture when the slide member is in said second position.

3. A security mounting substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

4. A picture frame having, on the back thereof, at least one security mounting according to any of claims 1 to 3.

5. Any novel feature or combination of features described herein.