GB2172135A

GB2172135A - Lighting system combined with an artificial tree

Info

Publication number: GB2172135A
Application number: GB08605709A
Authority: GB
Inventors: Royston Francis Allen; Janos Kecskes
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-03-08
Filing date: 1986-03-07
Publication date: 1986-09-10
Also published as: GB8605709D0

Abstract

An artificial Christmas tree of which the trunk comprises a plurality of lengths of tube 30 assembled end-to-end, one above the other by tubular connectors 31 each having a plurality of sockets 32 extending generally radially and slightly upwardly therefrom to which the branches 33 of the tree are attached, is combined with a lighting system consisting of a plurality of parallel- connected pairs of conductors 35,36 respectively extending along the branches and across which low- voltage (6 or 12 volts) electric bulbs are connected, the pairs of conductors being connected to a step-down mains transformer in the base 34 of the tree. <IMAGE>

Description

SPECIFICATION Lighting system The invention relates to a lighting system for artificial trees, such as Christmas trees, which are illuminated by an array of electric light bulbs distributed throughout the branches of the tree.

Domestic Christmas trees are conventionally decoratively illuminated by a string of low-voltage bulbs connected in series at spaced locations along a cable or flex connected to a mains plug, for example twenty series-connected 12-volt bulbs in the case of a 240-volt mains supply, the cable or flex being draped over the branches of the tree with the individual bulbs positioned to provide a desired decorative effect. In the case of a large tree two or more strings of bulbs are necessary to achieve adequate coverage of the tree by the lighting system.

Such lighting systems necessitate that the Christmas tree be re-draped each year on a new or re-erected artificial tree, and to be removed and stored at the end of the festive season. These operations can not only be tiresome but also involve risk of electric shock from the mains supply voltage. The use of mains voltage also presents the risk of fire. If one of the series-connected bulbs should burn out, all the bulbs of the string will fail to light and it is often a time-consuming and irritating job to locate and replace the faulty bulb.

Some lighting systems overcome this last problem by including means so that only the faulty bulb of a string goes out, but such systems are not completely reliable and the cutting out of circuit of the faulty bulb increases the voltage drop across the bulbs of the string which remain illuminated with the risk of further bulbs burning out.

The object of the invention is to provide an artificial tree equipped with a built-in lighting system which overcomes the above drawbacks of existing systems and which can be manufactured economically from standardised components which enable trees of different heights to be easily constructed.

It has been previously proposed in US Patent No. 3,617,732 to provide an artificial tree comprising a tubular trunk up which electric conductors extend from a voltage reduction means in a base member to a plurality of electric sockets along the trunk into which can be plugged limb members carrying electric wires and lamps which through the plug and socket connections are connected in parallel with the electric conductors along the trunk.

The tree is thus equipped with a low-voltage lighting system with parallel-connected lamps.

However the tree is expensive to fabricate and has a height determined by the length of the tubular trunk.

The invention consists in an artificial tree of which the trunk comprises a plurality of lengths of tube which are assembled end-toend, one above another, by tubular connectors each having a plurality of sockets extending generally radially therefrom, and preferably slightly upwardly, to which the branches of the tree are attached, in combination with a plurality of parallel-connected pairs of insulated conductors which respectively extend along and are secured to, wound around, woven in with, moulded in, enclosed within or otherwise assembled to at least some of the branches of the tree, and a plurality of low-voltage electric bulbs of which the filaments are connected across the conductors of the respective pairs of conductors along a branch either directly or via complementary lamp sockets disposed along the branches and of which the contacts are connected to the respective conductors of a pair.

The harness is fed with current via the common input from a low voltage source, preferably by a step-down transformer from the mains supply. A battery may alternatively be used. By "low-voltage" is meant a voltage which is incapable of producing an electric shock, such as 12 or 6 volts. The supply source should provide a limited current output to reduce the risk of fire, and may include a resettable cut-out to take care of any overload or short-circuit which may arise.

In one embodiment, the trunk or stem of an artificial tree comprises a plurality of lengths of tube, which are assembled end-to-end, one above the other, by tubular connectors each having a plurality, conveniently five or six, of smaller branch sockets projecting generally radially therearound, and preferably slightly upwardly, into which further tubular members are inserted to form the branches of the tree.

Each pair of conductors, which may be formed of individual insulated wires or a composite insulated wire, is threaded up the trunk tube and out through different smaller branch sockets into respective tubular branches. Each tubular branch may be assembled in two halves to facilitate connecting the conductors to the contacts of a lamp carried by the tubular branch. Instead of locating the wires inside tubular members forming the branches they may be wound around, woven in with, moulded within or otherwise assembled to the branch members which may be solid.

A feature of the invention consists in providing the individual components, viz trunk tubes, connectors with branch sockets, and branches, of which the tree is constructed with in-built conductors so that a tree of any desired height can be produced by assembling an appropriate number of components together, the conductors in one component being electrically connected to the conductors of another component when they are assembled together.

In order that the invention may be more clearly understood, reference will now be made to the accompanying drawing, in which: Figure 1 is an exploded perspective view of a tree equipped with the lighting system of this invention, Figure 2 is a side view of a tubular connector of Figure 1, Figure 3 is a section through a fragment of a modified construction of tree on an enlarged scale, and Figure 4 is a section taken along the line A A in Figure 3.

Figure 1 diagrammatically represents an artificial Christmas tree having its trunk constructed of a plurality of lengths of tube 30, conveniently of plastics material, which are assembled end-to-end one above the other, by inserting their ends into tubular connectors 31 (see also Fig. 2), also conveniently made of plastics material, the number of tubes 30 depending upon the desired height of the tree.

Each connector 31 has five branch sockets 32 of smaller diameter than the tubes 31, which project radially outwards, and slightly upwardly and into which further tubular members 33 are inserted to form the branches of the tree. The lower end of the trunk 30 is inserted in a base 34 which constitutes a housing for a step-down mains transformer or is provided with an electrical socket into which the output from such a transformer can be plugged.The output terminals of the transformer or socket are connected respectively with two bundles 35,36 of insulated electric wires, the insulation being differently coloured on the wires of the bundles so that pairs of wires, one from each bundle, may be readily selected for threading through the respective branch socket 32 and into the associated branch tubular member 33 where the wires of a pair are respectively connected to the contacts of lamp sockets 37 disposed at spaced intervals along the length of a branch member 33. Conveniently the branch tubular members are assembled from part-cylindrical portions or halves 33a, 33b to facilitate making the electrical connections to the contacts of the parallel-connected lamp sockets 37 whereafter the two portions of the branch tubular member are stuck or otherwise secured together.Lamp bulbs 11 are plugged into the respective lamp sockets 37. The lengths of the respective pairs of wires may be such as to provide sufficient play to permit the branch members 33 to be withdrawn from their respective branch sockets and laid parallel to the trunk 30 when the tree is to be stored. The trunk tubes 30 and the connectors 31 may, if desired, be secured together by adhesive or in any other convenient manner.

Appropriate "foliage" may be applied to the trunk and branches of the tree.

With the construction described, all the bulbs are connected in parallel. If one bulb burns out or there is a bad connection none of the other bulbs is affected. There is no risk of shock or fire.

Figure 3 shows a fragment of a modified construction of tree in which the various components from which the tree is built-up each includes its own section of the electric wiring circuit, the operation of assembling the components together at the same time completing the electric circuits from the base of the trunk to the bulbs on the branches.

As shown the moulded plastic trunk tubes 100 of the desired length have plain upper ends and stepped lower ends, the step portion 101 having an external diameter which will fit tightly within the bore at the upper end of a tube 100. The necessary change in the bore diameter from one end to the other can be achieved by the draw on the moulding.

Along diametrically opposite zones of the internal bore of each tube are two strips 102,103 respectively of conducting foil, e.g.

thin copper strip, of which the ends are folded over the ends of a tube length.

The connectors 104 which join together successive lengths of tube 100 and also comprise the branch sockets 105 are moulded in two parts a, b the division being along the centre lines of the sockets 105 as indicated by the line A-A. The lower end of the bottom part a is moulded with a step formation 106 to fit within the plain upper end of a tube 100 and the upper end of the upper part b has a diameter into which the step portion 101 at the lower end of the tube 100 is a push fit.

The inner peripheral zone of each of the opposing faces of the two parts a and b is each formed with an annular groove 107, 108 respectively in each of which is located a metal ring 109, 110 respectively. Strip copper or other metal contacts 111, electrically connected to the metal ring 109, e.g. by soldering, extend radially from the ring in each of the channels of the lower parts of the branch sockets 105 which are integral with the lower part a and have their outer ends folded over the outer ends of the channels. Likewise the metal ring 110 is electrically connected to six strip metal contacts 112 disposed radially in each of the channels of the upper parts of the branch sockets and having their ends folded over the outer ends of the channels.

When the two parts a and b of a connector are joined together, for example by means of an adhesive, the metal rings 109,110 are maintained electrically separated, for example by sticking them in their respective grooves or by an interposed member of insulating material. Before joining the parts a and b together, two metal strip conductors 11 7,118 are positioned in their respective bores and at intermediate points along their lengths are electrically connected to the metal rings 109,110 respectively, the conductors lying along the walls of the bores which will be diametrically opposite to each other when the two parts a and b are secured together.Opposite ends of the conductors 117,118 are bent around opposite of the connector so that they come into electrical contact with the conductors 103,102 in the tubes 100 when the latter are assembled to opposite ends of the connector. If desired the ends of the tubes 100 and connectors may be provided with keying means to ensure contact between the conductors of adjacent components when assembled together.

The connections between the conductors 117,118 and the rings 109,110 respectively may be made by soldering, for example, by forming the conductors with flattened loop portions 117' and 118' which project through gaps formed in the inner walls of the grooves 107 and 108 respectively and contact the respective metal rings to which they are soldered.

The tree branches are formed by members 119 along which is secured a pair of wires 120 having one or more lamps 121 and their holders, connected thereacross in parallel. At the trunk end of the branch member the wires 120 are connected to metal strip contacts 122,123 respectively which are adapted to make electrical contact with the contacts 111,112 respectively in a branch socket when the branch is inserted in a socket to connect the lamps along the branch to the supply input, each of the contacts 111 being connected via the ring 109 to the strip conductors 117 and 103 to the base of the tree trunk, and each of the contacts 112 being connected via the ring 110 to the strip conductors 118 and 102 to the base of the trunk. The base of the trunk may be constructed similar to the base shown in the embodiment of Figure 1 and contain a step-down mains transformer or a connector for connection to an external transformer.

The tube sections 100 and connector sections 104 may be secured together by means of a central rod 124 made of or sheathed in insulating means and providing with a screwed end or ends, or other means for clamping the tubes 100 and connectors 104 together and ensuring good electrical contact between the ends of the successive strip conductors 103,117 and 102,118.

As with the previous embodiment the tree may be provided with appropriate "foliage".

Claims

1. An artificial tree of which the trunk comprises a plurality of lengths of tube which are assembled end-to-end, one above another, by tubular connectors each having a plurality of sockets extending generally radially therefrom, and preferably slightly upwardly, to which the branches of the tree are attached, in combination with a plurality of parallel-connected pairs of insulated conductors which respectively extend along and are secured to, wound around, woven in with, moulded in, enclosed within or otherwise assembled to at least some of the branches of the tree, and a plurality of lowvoltage electric bulbs of which the filaments are connected across the conductors of the respective pairs of conductors along a branch.

2. An artificial tree according to claim 1, wherein each pair of conductors extends from the base of the tree through one or more lengths of tube forming the trunk and one or more tubular connectors and emerges through a socket to extend along a branch member of the tree.

3. An artificial tree according to claim 2, wherein the branch members are tubular inside which each pair of conductors are located when they emerge from the sockets.

4. An artificial tree according to claim 1, wherein the individual components, viz trunk tubes, connectors with branch sockets and branches, of which the tree is assembled, each includes its own section of the electric wiring circuit, the operation of assembling the components together also completing the electric circuits from the base of the trunk to the bulbs on the branches.

5. An artificial tree according to claim 4, wherein a tubular connector includes two conductors extending axially in the tubular body each of which connects with two annular conductors respectively extending around the inner ends of the radial sockets and connecting respectively with one of a pair of contacts in each socket.

6. An artificial tree according to claim 5, wherein said two axial conductors are exposed at both ends of a tubular connector and disposed to make electric contact with respective conductors extending axially along a trunk tube and exposed at the ends thereof.

7. An artificial tree according to any preceding claim, wherein the individual components are held assembled together by an axially extending rod.

8. An artificial tree according to any preceding claim in combination with a source of low voltage connected to supply current to the parallel-connected pairs of conductors.

9. An artificial tree according to claim 7, wherein the low voltagesource comprises a step-down transformer fed from the mains supply.

10. An artificial tree constructed as described with reference to Figures 1 and 2 of the drawings.

11. An artificial tree constructed as described with reference to Figures 3 and 4 of the drawings.