AU2013206524A1 - Safety mounting - Google Patents

Abstract

SAFETY MOUNTING A safety mounting has: a base which, in use is adapted for connection to a mechanical earth; a pair of jaws mounted to the base which are biased in a lateral direction toward or away from each other; a breakaway member having a pair of angled cam surfaces which are engagable with the jaws on the base thereby to retain the breakaway member on the base; 3 the angle of the cam surfaces being such that, when the breakaway member is retained on the base the biasing action of the jaws against the cam surfaces applies an upward retaining force on the breakaway member to keep it retained on the base and against the action of its weight; but when a downward force in excess of a predetermined value is applied, the cam surfaces operate to overcome the lateral bias of the jaws whereupon the breakaway member is released 3 from connection with the base. (Fig. 2) U, zaA p r~ -

Description

SAFETY MOUNTING The present invention relates to a safety mounting which may be used, for example, to suspend a curtain, a coat hook or towel rail. Such mountings have particular, though not exclusive 5 application in Mental Health and Psychiatric establishments. Fixtures and fittings used in such establishments are typically of a kind which will prevent, or at least inhibit the patient using them to inflict self harm. The generally accepted term for such fixtures is 'anti-ligature'. One form of safety mounting is known from WO 96/10132 which shows a socket intended to be 2 mounted to a mechanical earth such as the wall or ceiling of a building. A spigot (to which, for example, a hook or curtain rail may be attached) carrying a resilient '0' ring projects into the socket, whereupon the '0' ring engages with a suitable detent within the socket to cause the spigot to be retained within the socket. Under significant force (such as a patient seeking to hang from the spigot), the ring deforms to release the spigot and prevent harm to the patient. 5 This form of mounting is said to suffer from a difficulty when downward force is applied at a point laterally displaced from the spigot. The resultant bending moment is said to cause jamming of the spigot in the socket and prevent release. A further form of safety mounting, said to ameliorate such problems, is shown in GB2351758, which employs magnetic attraction between a housing connected to a building surface and any element (such as a curtain rail) which it is ) required to suspend from it. The magnetic connection provides a 'breakaway' under a predetermined force and thereby prevents self-harm. The present invention provides an alternative mounting. 5 One embodiment of the present invention provides a safety mounting having: a base which, in use is adapted for connection to a mechanical earth; a pair of jaws mounted to the base which are biased in a lateral direction toward or away from each other; a breakaway member having a pair of angled cam surfaces which are engagable with the jaws on the base thereby to retain the breakaway member on the base; the angle of the cam surfaces being such that, when the 0 breakaway member is retained on the base the biasing action of the jaws against the cam surfaces applies an upward retaining force on the breakaway member to keep it retained on the base and against the action of its weight; but when a downward force in excess of a predetermined value is applied, the cam surfaces operate to overcome the lateral bias of the jaws whereupon the breakaway member is released from connection with the base. 5 Embodiments of the present invention will now be described, by way of example, and with reference to the accompanying drawings in which: 113411598v3 Fig. 1 is a plan view of a curtain rail equipped with a safety mounting according to an embodiment of the present invention; Fig. 2 is an exploded perspective view of a detail of Fig. 1; 5 Fig. 3 is section through a detail of Fig. 2; Figs 4 and 5 are exploded perspective views of a modification of the embodiment of Figs 1 and 2. Referring now to Fig. 1, a curtain rail 10 is mounted at each end to a base 12. The base 12 is ) adapted to be connected fixedly to a mechanical earth, which in the present embodiment is the wall of a building. Thus, the wall to which the curtain rail 10 is mounted, via the bases 12, extends parallel with the plane of the paper in Fig. 1. A safety mounting enables connection of the rail to the bases 12 in such a manner that the rail 10 is released, automatically, from its connection with the bases upon the application of a predetermined downward force. Thus, a 5 patient seeking to hang themselves from the rail will not be successful because their weight on the rail 10 will cause the rail to breakaway from the bases. Referring now additionally to Fig. 2, each base 12 is connected to the mechanical earth by a T shaped wall bracket 14. The bracket 14 is fixed to a vertical wall by means of a pair of screws ) 16 which project through apertures 16A in the bracket. The bracket 14 has a horizontally extending web 18 which projects perpendicularly. The web 18 supports a pair of biased retaining jaws 20. In the present embodiment, the jaws 20 are provided by a single leaf spring. The leaf spring is connected to the web 18 by means of two screws 22 which project through apertures in the base 24 of the leaf spring. For cosmetic purposes, each base 12 has a dome 5 shaped housing H which fits around the wall bracket 14 and a cover flange CF which encloses the base of the housing H while leaving an opening so that the jaws 20 are accessible from below. The curtain rail 10 has, at each end, a breakaway member 30. Each breakaway member is 0 connected to a spring 42 which engages with a detent 44 within the breakaway member 30. The spring 42 projects through an aperture 46 on a plate 48 which is then connected to the rail 10 by means of screws 50. In this way, the rail 10 is connected to the breakaway member 30. The spring 42 provides an additional safety feature. 5 In use, the rail 10 is connected to the base 12 at each end by the connection of a breakaway member 30 with the of jaws 20. Referring additionally to Fig. 3, the breakaway member 30 has a substantially rhomboidal cross-section. Thus, it includes a pair of insertion cam surfaces 32A, B which are wedge-shaped in the direction of insertion, indicated by Arrow I in Fig. 3. When the breakaway member is urged into connection with the jaws, the insertion cam surfaces 32A, B engage first of all with the small, outwardly-projecting flanges 21 at the ends of the limbs 20A, B. The flanges 21 serve to guide the insertion surfaces 32A, B into the mouth of the jaws 20. As 5 the breakaway member 30 is urged upwards into the jaws, the jaws 20 apply an inwardly-acting biasing force to each of the insertion surfaces 32A, B of the breakaway member 30. Since the lateral biasing forces applied by the jaws are equal and opposite, they cancel each other and there remains only a resultant downward force on the breakaway member 30, acting to force it out of the jaws 20. If the breakaway member 30 continues to be pushed upward with sufficient ) force to overcome this downward force (combined with its own weight), the breakaway member 30 will project ever further into the mouth of jaws and the jaws 20 will continue to be forced apart. Eventually, the breakaway member 30 will be forced into the jaws to a sufficient extent that the 5 jaws 20 will bear upon the short, mutually parallel, intermediate surfaces 34 of the breakaway member 30. At this point, because the reaction force applied to the intermediate surfaces 34 of the breakaway member 30 by the lateral bias of the jaws 20 acts only horizontally, there will be no downward force (other than its weight and that of the curtain rail to which it is attached) applied to the breakaway member 30 to which it is connected. ) Further insertion of the breakaway member 30 into the jaws 20 then causes the jaws to bear upon retention cam surfaces 36C, D of the breakaway member. The retention surfaces 36C, D can be thought of as akin to the 'mirror' of the insertion surfaces 32A, B. That is to say that they are angled in the opposite sense. Accordingly, the lateral bias of the jaws 20 upon the retention 5 surfaces 36C, D now results in an upward retaining force upon the breakaway member 30. This will, during insertion, cause the breakaway member 30 to be pulled fully into the mouth of the jaws 20 until the flanges 21 bear upon the neck 38 of the breakaway member 30. At this point, the breakaway member 30 is fully inserted into the jaws 20 whose inward lateral bias against the retention surfaces 36C, D of the breakaway member acts to retain the breakaway member (and 0 thus the rail 10 and any curtain hanging from it) in engagement with the base 12. The angle and size of the retention surfaces 36C, D and the lateral bias applied by the jaws 20 (i.e. in this case the spring rating and dimensions of the leaf spring providing the jaws 20) is chosen to be such that the retention force is sufficiently large to hold a curtain rail 10 and a 5 curtain hanging from it; but that the retention force is sufficiently small that if the weight of a person is added to that, the retention surfaces 30C, D will then act as wedges driven by a force sufficiently large to force open the jaws 20 against the action of the lateral bias and provide full I release of the breakaway member 30 (and thus the curtain rail 10) from engagement with the base 12, thus preventing self harm by anyone seeking to suspend themselves from it. Figs. 4 and 5 show a modified form of base, in which like elements are identified with like 5 reference numerals. In this modification, the jaws 20 provided by the leaf spring are connected to the mechanical earth which, in this instance is a ceiling. Accordingly, the jaws are screwed into a planar fixing bracket 114 (rather than a T shaped bracket 14 of Figs. 1 and 2). This reduces the depth of the base structure and thus the housing H is of shallower and simpler construction. The present embodiments have illustrated jaws provided by a pair of leaf springs and, more specifically, a pair of leaf springs which are formed from a single leaf spring the base of which enables connection of the jaws to the base. It is equally possible for other forms of biased jaws to perform the same function such as, for example a pair of ribs biased inward or outward by 5 compression springs, or tension springs as appropriate. Equally, the jaws illustrated have a mutually-inward biasing action against cam surfaces. It is equally possible, for example by reversing the directions of the cam surfaces, for the jaws to be biased outwards, whereupon the cam surfaces will then encompass the jaws, forcing them together. ) The present embodiment illustrates use of the safety mounting for a curtain rail. Equally, it may be employed for a wide variety of fixtures, including by not limited to a coat hook; wardrobe rail; towel rail; curtain track; shower track and toilet roll holder or indeed any other fixture or fitting from which it is possible to suspend something that may enable self-harm to occur. 5 The various modifications are not restricted to use with the embodiments in connection with which they are first described and all modifications may be employed with all embodiments as appropriate. 0:

Claims (7)

1. A safety mounting having: a base which, in use is adapted for connection to a mechanical earth; 5 a pair of jaws mounted to the base which are biased in a lateral direction toward or away from each other; a breakaway member having a pair of angled cam surfaces which are engagable with the jaws on the base thereby to retain the breakaway member on the base; the angle of the cam surfaces being such that, when the breakaway member is retained on 3 the base the biasing action of the jaws against the cam surfaces applies an upward retaining force on the breakaway member to keep it retained on the base and against the action of its weight; but when a downward force in excess of a predetermined value is applied, the cam surfaces operate to overcome the lateral bias of the jaws whereupon the breakaway member is 5 released from connection with the base.

2. A safety mounting according to claim 1 wherein the jaws are a pair of leaf springs.

3. A safety mounting according to claim 2 wherein the leaf springs have a neutral position ) and the action of the cam surfaces engaging the leaf springs causes the springs to deflect thereby to provide the lateral biasing of the jaws against the cam surfaces.

4. A safety mounting according to any one of the preceding claims wherein the jaws are biased inwardly toward each other and the cam surfaces are insertable between the jaws 5 to cause them to deflect outwards.

5. A safety mounting according to any one of claims 1 to 4 wherein the jaws are biased outwardly away from each other and the cam surfaces may encompass the jaws to cause them to deflect inwards. 0

6. A safety mounting according to any one of the preceding claims wherein the breakaway member carries a utility fixture selected from the group consisting of a hook, a rail for a towel or curtain. 5

7. A safety mounting substantially as described herein and with reference to the accompanying drawings.