A CONNECTOR DEVICE

Abstract: A connector device comprises a wire (40, 50) having respective end regions (41, 42, 51, 52) and a central region (43, 53) therebetween, the end regions (41, 42, 51, 52) being bent so as substantially to encircle respective spaced apart locations intermediate the ends of a spring element or elements (60, 70) to be connected, and the central region (43, 53) extending as a loop between said end regions (41, 42, 51, 52).

Description: DESCRIPTION A CONNECTOR DEVICE This invention concerns a device for connecting an elongate spring element, intermediate it ends, to means for suspension of the element. The invention also concerns a device for connecting together a plurality of side by side or stacked elongate spring elements, intermediate their respective ends, whilst also providing means for suspending said elements. European Patent Aplication No. 91106803.9 (Publication No. 455165) discloses a baby bouncer which essentially comprises a transversely arranged cantilever spring, in the form of an elongate steel strip of bowed configuration, and a harness (for a baby) which is suspended from the ends of the cantilever spring by cords or ropes. A suspension chain is connected to the cantilever spring at approximately its mid point by way of a connector and in use the free end of the suspension chain is clamped over a door lintel or connected to a ceiling mounted hook so that the whole assembly is suspended therefrom. When a baby is installed in the haness its weight acting via the ropes causes flexure of the cantilever spring. When the baby alternately bends and straightens its knees, bouncing of the baby ensues aided by the cantilever spring, the ends of which flex upwards and downwards about the centre thereof. It has been found that drilling holes in the cantilever spring to facilitate connection of the suspension chain thereto weakens the cantilever spring and greatly increases the likelihood of mechanical failure in use. Moreover, by using rigid or fixed connections at the centre of the cantilever spring suc as nuts and bolts, welding or riveting, the cantilever spring is prevented from flexing freely about its centre and a dead area is created about the centre of the cantilever spring where virtually no flexure occurs. It is an object of the invention to provide a connector device which, without requiring any cuts or apertures to be formed in the cantilever spring, enables a cantilever spring to be connected to a suspension means without requiring any rigid or fixed connection to the cantilever spring. In this respect, cuts or apertures inevitably introduce areas of weakness into the cantilever spring which may be subject to stress on loading or flexure of the cantilever spring and could ultimately lead to complet failure, i.e. fracture of the cantilever spring. Rigi or fixed connections, such as by welding or rivets (th latter also requiring apertures), are similarly subjec to stress upon loading or flexure of the cantilever spring and will inhibit flexure in the region of the connection. According to a first aspect of the present invention, a connector device of either type herein¬ before defined comprises a wire having respective end regions and a central region therebetween, the end regions being bent so as substantially to encircle respective spaced apart locations intermediate the end of a spring element or elements stacked one on top of the other to be connected, and the central region extending as a loop between said end regions. According to a second aspect of the invention, an assembly for suspension comprises one or more elongate spring elements stacked one on top of the other with two connector devices mounted thereon intermediate the ends of the spring element or elements, each connector device consisting of a wire which is bent so as to hav first and second end regions substantially encircling the spring element or elements at spaced apart locations and a central region which forms a loop - i - between the first and second end regions, the two connector elements being mounted closely adjacent to each other in overlapping relation such that the loops provided by their central regions are substantially aligned and their respective first end regions lie side "by side and their respective second end regions lie side by side, the first end regions of the respective connector devices being bent in opposing directions from their respective central regions and the second end regions of the respective connector devices also being bent in opposing directions from their respective central regions. With this arrange¬ ment, loading upon suspension of the assembly, more particularly with an additional load attached thereto, is evenly spread between the two devices and their end regions so the risk of fracture in the vicinity of the bend between any end region and its adjoining central region is minimized. The connector device of the present invention allows the load to be carried by the loop provided by the central region thereof whilst the end regions thereof can flex to suit the curvature of the spring element or elements. Meanwhile, the spring element or elements can freely flex about their centre which is directly under and opposite the loop which connects it to the suspension means. In this way the connector device of the present invention completely avoids any rigid section of the spring element or elements betwee the end regions of the connector device and thereby allows for maximum flexure of the spring element or elements. The elongate spring elements suspended and/or connected by the device or devices may be in the form of flat strips. Alternatively, they may consist of profiled strips, i.e. strips having an angled or curve cross section, possibly of complex configuration. The elongate spring elements may all be of the same length, but in a preferred embodiment they are each of differing length with the longest spring element at th top of the stack and the shortest at the bottom. The wire of which the devices are formed may be conventional steel wire of round cross section. However, wire of other material and/or of flattened or other non-circular cross section is also possible within the scope of the invention. The device of the invention is specifically proposed as a means of suspension of an elongate cantilever spring as used in a baby bouncer of the typ previously described hereinabove. An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which. Fig. 1 shows a schematic front view of a baby bouncer comprising a connector device in accordance with the present invention; Fig. 2 shows a fragmentary perspective view of two connector devices in accordance with the present invention mounted so as to connect and enable suspension of two elongate flat spring elements, and Fig. 3 shows a stack of three spring elements, each of differing length, which can be used in place of the single cantilever spring shown in the baby bouncer of Fig. 1. Referring to Fig. 1 the baby bouncer shown comprises a frame, designated generally by reference numeral 10, and a bouncer which is suspended therefrom. The frame 10 comprises a U-shaped base portion 12 of tubular metal provided approximately midway along each side limb with respective, upwardly curving sockets 14, and a U-shaped upright portion 16, also of tubular metal. The sockets 14 are simply bolted to the insides of the side limbs of the base 12 and their positions can be varied by fixing them by way of alternate holes 18 provided along the limb. The ends of the limbs of the upright portion 16 are inserted into the sockets 14 and additional, releasable fastening means may be provided. A hook 20 is connected to the upright portion 16, approximately midway along its crosspiece 22, so as to project down¬ wardly in the erect condition of the frame 10. It will be appreciated that the frame 10 can readily be assembled from the component parts, namely base portion 12, sockets 14, upright portion 16, hook 20, and relevant bolts and/όr other fastener means and placed at any desired position, and also readily dis¬ mantled and packed flat for storage. The bouncer comprises suspension means in the for of a metal chain 24, a transversely arranged cantileve spring 26, in the form of an elongate steel strip of bowed configuration and a harness 30 (for a baby) suspended by two cords or ropes 32 which are attached adjacent the respective ends of the spring 26. The spring 26 is, in this preferred embodiment, approximately 60cm long and 2cm wide. It is attached at approximately its mid point to the suspension chain 24, by way of a connector device 34 in accordance with the present invention, so that, when suspended and without load, its end regions extend at an upward inclination. In this respect, the spring 26 is shown in three positions in Fig. 1, the unloaded position being indicated by reference letter A. At its ends the spring 26 is provided with eyelets 38 for connection of the ropes 32. The spring 26 is selected to have appropriate initial curvature and spring characteristics for down¬ ward flexure of its end regions to positions B and C, as indicated in Fig. 1, and for bouncing of the baby. Position B represents the loaded condition of the spring 26, when the baby is placed inthe harness 30 but is inactive. The configuration of the spring under these conditions depends entirely on its spring characteristics and on the size of the load applied, but generally it should be approximately straight, i.e. horizontal. Position C represents the maximum downward flexure fo the end regions of the spring 26, and would normally be achieved only during bouncing. In Fig. 1 position C is in broken lines and the harness lines are not shown. When a baby is installed in the harness 30, its weight, acting via the ropes 32, causes flexure of the spring 26 from position A with upwardly extending end regions to position B where the end regions have been brought down approximately to the level of the central region. Upon application of further downward force the end regions of the spring flex downwards. When the additional downward force is released, bouncing of the baby ensues aided by return of the spring 26 to straight configuration or upward flexure, and continued oscillation. Referring now to Fig. 2 the connector device according to the present invention will be described in detail. As shown two substantially identical wire connector devices 40, 50 hold together two flat cantilever spring elements 60, 70 which are laid on top of each other. The devices and the springs are symmetrically arranged about a common centre line indicated at A-A. The first device 10 has first and second end regions 41, 42, which are each bent into approximately rectangular loops which encircle the two springs 60, 70 at spaced locations substantially equidistant from the line A-A at opposite sides thereof. Between the end regions 41, 42, a central region 43, which links them, extends perpendicular as a handle. The loops formed by the end regions 41, 42 are open, as shown, at the same side as each other. The second device 50, has comparable first and second end regions 51, 52 lined by a central region 53. The devices 40, 50 are mounted closely adjacent each other, even in contact at some points, so that their respective end regions 41, 51 and 42, 52 and respective central regions 43, 53 lie side by side. It will be noted that the looped end regions 51, 52 of this second device 50 are again open at the same side as each other, but at the opposited side to the end regions 41, 42 fo the first device 40. The side be side central "regions 43, 53 provide a common handle for. suspension of the springs 60, 70. It is envisaged that a further load will be suspended from the springs 60, 70. Upon oscillation of the springs 60, 70 the devices 40, 50 are under greatest stress in sections where they are bent between the central regions 43, 53 and the respective end regions 41, 42 and 51, 52. However, the likelihood of stress fracture in any of these places is minimised by the even sharing of the load brought about by the particular arrangement ilustrated with the looped end regions of the respective devices open in opposite directions at each side of the centre line A-A. As mentioned, this connector device has particular application to a baby bouncer in which a harness for the baby is suspended from respective ends of an elongate cantilever spring, which is itself centrally suspended from an overhead frame or lintel. In order to achieve the desired degree of vertical flexure to cater for a wide range of baby weights the spring takes the form of a relatively narrow metal strip of about 2c width. Mounting such a strip by means of a rigidly connected loop entails drilling two holes through the strip, either side of the centre line or insertion and rivet-like connection of limbs of the loop. This has proved unsatisfactory because in addition to standard reduction of strength caused by the provision of holes, the strip, in use, tended to flex or oscillate only between the loop connections and the respective ends, thus imposing maximum stress in the weakest areas of the bar. During testing, fracture of the strip in the area of one of the holes was found likely to occur after between 20,000 and 30,000 oscillations. The connector device of the present invention overcomes this problem and improves the safety and performance of the cantilever spring used in the above described bouncer. With the illustrated mounting arrangement, for example, using two devices 40, 50, and a bowed support spring 70 connected centrally below the main spring 60, over 100,000 oscillations were possible before any risk of fracture. As well as avoiding any drilling of holes, by avoiding any rigid connection the spring 60 now oscillates about its centre line, rather than about the roots of the connector loop, which eliminates excess stress at those places. Furthermore, as the effective spring length is greater with central flexure, a greater flexibility is apparent and the characteristic of the "bounce" is improved. In other embodiments, a single connector device in accordance with the present invention may be satisfactory as connector/suspension means. Further¬ more a single strip or a plurality of strips may be connected and/or suspended using such a device or a pair of devices. When two connector devices are used it is important that they are mounted back to back, i.e. in opposite orientations, so that open ends of the looped end regions lie at opposing or complementary positions. In this respect it does not matter, in such cases, whether each individual connector device has its end regions folded in the same direction or in opposing directions so long as they are mounted to complement those of the other device. Referring now to Fig. 3 of the drawings, there is shown a stack of three cantilever spring elements 101, 102 and 103 which can be used in place of the single cantilever spring element shown in the baby bouncer of Fig. 1. Although not shown the three spring elements are connected together and suspended using a connection device or a pair of such devices in accordance with the present invention. This combination of cantilever spring elements and connection device has been found to be less prone to mechanical failure than the conventional arrangement of a single cantilever spring element supported/connected by means of a fixed or rigid connection.

Claims: - I ll - CLAIMS 1. A connector device comprising a wire having respective end regions and a central region there¬ between the end regions being bent so as to substantially encircle respective spaced apart locations intermediate the ends of an elongate spring element or elements to be connected, and the central region extending as a loop between the said end regions. 2. A suspension assembly comprising a connector device according to claim 1 in combination with one or more elongate spring elements stacked one on top of the other. 3. A suspension assembly comprising one or more elongate spring elements stacked one on top of the other with two connector devices according to claim 1 mounted thereon intermediate the ends of the spring element or elements, each connector device consisting of a wire which is bent so as to have first and second end regions substantially encircling the spring element or elements at spaced apart locations and a central region which forms a loop between the first and second end regions, the two connector elements being mounted closely adjacent to each other in overlapping relation such that the loops provided by their central regions are substantially aligned and their respective first en regions lie side by side and their respective second end regions lie side by side, the first end regions of the respective connector devices being bent in opposing directions from their respective central regions and the second end regions of the respective connector devices also being bent in opposing directions from their respective central regions. 4. A suspension assembly according to claim 2 or 3, wherein the elongate spring elements are each of differing length with the longest spring element at the top of the stack and the shortest at the bottom. 5. A baby bouncer comprising suspension means, a suspension assembly according to any one of claims 2, 3 or 4, which suspension assembly is connected to and suspended from the suspension means by means of the loop provided by the central region of the or each connector device and a harness suspended from the respective ends of the elongate spring element or elements of the said suspension assembly.

Inventors: SPARKES CURTIS ALBERT, SPARKES, CURTIS, ALBERT
Applicants: KIRKMOSS LTD, KIRKMOSS LIMITED
Application year: 1993
Main classification: F16F1
IPC codes: A47D13, F16F1