GB2322185A

GB2322185A - Battery powered Christmas tree decoration shaped like a candle

Info

Publication number: GB2322185A
Application number: GB9803066A
Authority: GB
Inventors: Raymond Walter Harcombe
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-02-15
Filing date: 1998-02-16
Publication date: 1998-08-19
Also published as: GB9803066D0

Abstract

A lamp unit comprises a base part 12, an illumination part 14 and a clip part 42. The base part 12 contains a battery 26 for powering the illumination part 14 which may be an incandescent bulb or a fibre optic cable. The illumination part 14 may be designed to flicker or flash and may be controlled by a microchip and capacitor situated in the base part 12. The clip part 42 is adjustably mounted to the base part and comprises a pair of jaws 40, 46 resiliently biased together 50. The whole unit is shaped to resemble a candle.

Description

LAMP UNIT AND ARRANGEMENT FIELD OF THE INVENTION This invention relates to a lamp unit and arrangement.

BACKGROUND TO THE INVENTION It is known to decorate a Christmas tree and the like with lights or lamp units, so as to increase the visual appeal of the tree. We expect our lamp unit to find particular utility as a decoration for Christmas trees and the like, especially Christmas trees sited within domestic dwellings, and for simplicity much of the following description will relate to such use. However, it will be understood that the lamp unit could alternatively be used for other purposes, some of which are described below.

DESCRIPTION OF THE PRIOR ART Formerly, it was known to use candles to decorate a Christmas tree within a domestic dwelling, the candles being individually lit by the user. Burning candles are generally pleasant to observe so that their use in this manner increased the aesthetic appeal of the Christmas tree.

However, the candles suffered from the major disadvantages that (i) the naked flame(s) adjacent the tree branches and leaves presented a fire hazard, and (ii) the dripping wax could be damaging to lower tree branches or the floor covering of the dwelling, and potentially harmful to young children for example.

Because of the above disadvantages, the use of candles as Christmas tree lights has all but ceased, despite their visual appeal, to be replaced by electrically operated lights.

The electrically operated lights which are presently available for use on a Christmas tree are operated from the mains electricity, and include a set of lamp units, each including an incandescent bulb, which units are connected in series to a wire which is in turn connected to a source of mains electricity. Disadvantages of the known arrangements include that a source of mains electricity is required within a certain distance of the Christmas tree, or alternatively stated the Christmas tree is required to be sited within a certain distance of the source of mains electricity. In addition, the wire usually delivers mains voltage to the lamp units, which voltage is potentially lethal if a person should come into contact with it, perhaps because of a bared wire, for example. Any bared wire also presents a fire hazard.

Another major disadvantage is that because the lamp units operate in series, each one is required to be in working order to maintain the electrical circuit. If one of the lamp units is faulty, perhaps because the filament of its bulb has melted or otherwise become broken, or if the bulb is not properly contacting both of the terminals in the base of the unit, then current will not flow through any of the lamp units. Discovering which of the lamp units is faulty is widely recognised to be a time consuming task, and one which is often required the first time it is attempted to illuminate the tree lights each Christmas.

If the lamp unit is faulty because a bulb filament has been melted or otherwise broken, it is usually possible to replace the individual bulb. However, unless a replacement bulb is readily to hand, the less conscientious may instead seek to bridge the terminals of the faulty lamp unit, as by the insertion of a conductor such as aluminium foil, so as to bypass the defective bulb. Whilst this may achieve a short term solution in that the current can again flow through all of the lamp units, the reduction in the overall resistance caused by bypassing the defective bulb results in an increase in the current flowing through the remaining lamp units, so increasing the likelihood of the filament of another bulb melting.

Another disadvantage of these Christmas tree lights is that they are sold in predetermined numbers. A given size of Christmas tree will ideally require a certain number of lights, and this exact number may not be available. In addition, if the owner of a set of Christmas tree lights subsequently buys a larger or smaller tree, he or she may have to buy a new set of lights with a number of lamp units more suited to the new tree.

Furthermore, the maximum spacing between adjacent lamp units is predetermined by the manufacturer, and so the siting of the lights on the tree may be determined more by the length of wire between adjacent lamp units rather than the particular desire of the user.

"Stand alone" battery operated lamp units are also known, which comprise a base part and an illuminating part, the base part carrying a battery to provide electrical energy for the illuminating part. However, such lamp units are generally designed to provide a maximum amount of illumination for a maximum length of time, so that the battery or batteries required result in a large, heavy and cumbersome unit, not suited to use on a Christmas tree or the like.

DISCLOSURE OF THE INVENTION We seek to avoid or reduce the problems associated with the Christmas tree lights as above described.

According to the invention therefore, we provide an electrical lamp unit comprising a base part and an illuminating part, the base part incorporating a battery to provide electrical energy for the illuminating part, characterised in that clip means are attached to the base part.

The lamp unit of the invention is considerably smaller and lighter than the prior known battery operated lamp units; the provision of clip means enables the lamp unit to be clipped and retained in position where desired, for example upon a branch of a Christmas tree.

The invention thus provides individual lamp units which do not require mains electricity. The lamp units could be purchased individually or in sets of certain numbers, so that the required number can be bought depending upon the size of the tree. The number of lamp units required and/or used can be incrementally increased or decreased to cater for a subsequently-purchased larger or smaller tree. Should one lamp unit fail, there will be no effect on the remaining lamp units, so that the faulty lamp unit can be quickly identified and repaired or replaced as required.

Furthermore, the positioning of each lamp unit upon the tree can be chosen to provide the best visual effect, the positioning of the individual lamp units not being partly determined by the positioning of the adjacent lamp units.

Preferably, the clip means includes a resilient biassing means and a set of jaws, the resilient biassing means acting to urge the jaws together.

Usefully, the illuminating means comprises an incandescent bulb; alternatively, the illuminating means comprises a part of at least one fibre optic cable.

If the illuminating means is an incandescent bulb, it usefully has a working temperature lower than approximately 50 C, so as not to present a hazard to persons whose skin comes into contact therewith. Desirably, the bulb has at least one filament, and is adapted to flicker, to simulate the flame of a candle.

Alternatively, the lamp unit can be designed to flash intermittently. It is believed that such flashing will increase the expected lifetime both of the battery and also of the illuminating part, particularly if the illuminating part is an incandescent bulb. Such an embodiment will typically incorporate a microchip and a capacitor; preferably, the battery, microchip and capacitor are all located in the base part of the lamp unit.

Preferably, the base part is designed to simulate a small candle. Accordingly, the diameter of the base part is preferably less than 1cam, and in particular can be 0.5cm, whilst its length is approximately 8cm.

Usefully, the battery is a "AAA" battery, though a watch battery could alternatively be used. A compartment suited to the particular size and shape of battery can be provided in the base.

Preferably, the base part is manufactured of a plastics material, heat resistant to the temperatures involved.

Desirably, the material is not toxic. Desirably also, the material is bio-degradable. Preferably, the lamp unit is adapted for indoor use as in a domestic dwelling, but alternatively the lamp unit can be made waterproof and adapted for outdoor use.

Usefully, the base part includes switch means for selectively connecting and disconnecting the electrical circuit to the illuminating means. Preferably, the switch means is manually operable, but alternatively the switch means can be electronic and incorporate a detector so as to be activated by remote means such as an infra red emitter.

Such an arrangement could permit all of the lamp units within range and line of sight of the emitter to be activated substantially simultaneously.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig.l is a sectional view of a lamp unit according to the invention; Fig.2 is a sectional view of part of another lamp unit; Fig.3 is a side view of part of another design of lamp unit; and, Fig.4 is a bottom view of the embodiment of Fig.3.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS The lamp unit 10 of Fig.l comprises a base part 12 and an illuminating part 14. The illuminating part 14 in this embodiment comprises an incandescent bulb with a filament 16. Connected to filament 16 are wires 20,22, which connect the filament to a battery 26 in the base part 12.

For simplicity, in the embodiment shown the wires 20,22 are shown as continuous with the filament 16, though in preferred embodiments the filament terminates at contacts which are engageable with terminals of the wires in the base part 12, so that the bulb 14 is removable and replaceable.

The wire 20 is discontinuous, and engages a switch 30, which has a conductive member 32 which on movement of the switch (up and down as viewed), can be moved to make or break the electrical contact between the disconnected ends of the wire 20, in known fashion.

The battery 26 is fitted into a compartment in the base part 12, the compartment being shaped to accomodate a battery of predetermined size and shape. In this embodiment the battery 26 is a watch battery, the wire 20 engages the terminal at its top and the wire 22 engages the terminal at its side. In an alternative embodiment the battery is a "AAA" battery, with terminals at its top and bottom.

The embodiment of Fig.1 is of a lamp unit which illuminates ermanently when switched on. In an alternative embodiment the lamp unit can flash intermittently. In such an alternative embodiment, the base unit incorporates a microchip and a capacitor. Usefully, the microchip is one designated as "M3 7AD LM 3909N" as is available from "Maplin"(TM) stores in the U.K. Usefully also the capacitor is rated at 220 mF and 16 v. With such an embodiment, an incandescent bulb rated at 1 V and 10 mA has been found to be suitable.

In the embodiment of Fig.l. the battery compartment is closed off by a cap 34, which in this embodiment is a press fit but could alternatively be threaded. The cap 34 is affixed to one jaw 40 of the clip means 42. The jaw 40 is integral with an extension 44. Another jaw 46 is integral with extension 48. The jaw 40 and extension 44 is connected to the jaw 46 and extension 48 by a pivot pin 50. Wound around part of the pivot pin 50 is a coil spring (not shown), the terminal ends of which engage the extensions so that the spring biasses the extensions 44,48 apart and so biasses the jaws 40,46 together.

When it is desired to secure the lamp unit to the branch of a Christmas tree or the like, the extensions 44,48 are pressed together against the force of the spring so that the jaws 40,46 are forced apart. The jaws are passed one to either side of the branch whereupon the extensions are released and the spring causes the jaws to clamp the branch, so securing the lamp unit in place.

It will be understood that the size of the jaws 40,46 and the strength of the spring are chosen so as to be able to support the weight of the lamp unit 10. The cooperating surfaces of the jaws are shown flat for simplicity, but in reality would be serrated in known fashion, to enhance the retention of the jaws on the branch.

It will be understood in the embodiment of Fig.l that the orientation of the base part 12 in use, and thus the illuminating part 14, is determined by the orientation of the clip means 42. It will also be understood that the most pleasing aesthetic effect will be created with the base part being substantially vertical as shown, and to achieve this in the embodiment of Fig.l it will be necessary that the jaw 40 (at least) is substantially horizontal.

In some cases this requirement may limit the positioning of the lamp unit to an unacceptable amount, i.e it may be difficult to locate the lamp unit on a suitable branch of the tree. Accordingly, in the embodiment of Fig.2 there is disclosed a means for permitting limited changes in the relative orientation of the clip means 142 and the base part 112 (only part of which are shown). Thus, the jaw 140 carries a holder 52 which has a substantially part spherical recess 54 into which fits a correspondingly shaped boss 56 of the cap 134. The boss 56 is a sliding but frictional fit within the recess 54.

It will be understood that the boss 56 and thus the cap 134 and base part 112 can swivel by a limited amount relative to the recess 54, and thus to the jaw 140, so that in this embodiment the base part 112 can be vertical even if the jaw 140 is not horizontal.

In the embodiment of Figs.3 and 4, the plane of the jaws 240,246 are substantially parallel with the longitudinal axis A of the base part 212. This permits the base part and clip means to present a substantially flat bottom surface 60 upon which the lamp unit can stand when it is not secured by the clip means, the bottom surface 60 being substantially perpendicular to the longitudinal axis A so that the base part stands upright when the bottom surface 60 is resting of a horizontal surface such as a table top.

Also shown in this embodiment is a tray 62, which partly obscures the jaws 240,246 and extensions 244,248 when viewed from above. In addition, the tray can be patterned to increase the visual appeal of the lamp unit. In particular, the outer periphery of the tray 62 in this embodiment is circular, but in alternative embodiments could be shaped (and perhaps coloured) as a number of leaves for example.

The invention is not limited to use on Christmas trees, but could be used for other forms of decoration where required.

Thus, the lamp unit and arrangement could be used to decorate trees or garden furniture around a barbeque, as another example of its utility. Alternatively, the lamp unit of Figs.3 and 4 could be used in place of a candle in the event of an interruption in the mains electricity supply, the clip means of that embodiment permitting the lamp unit to stand on a substantially horizontal surface, or to be clipped in a position where illumination is necessary.

Also, the lamp unit could be used as a "night light" for a childs cot, the clip means permitting the lamp unit to be secured to the cot at a suitable location.

It will be understood that the lamp unit will have to conform to local regulations governing the manufacture, use and/or sale of electrical and/or electronic devices. In the U.K. these regulations include URN 95/626 concerning the electromagnetic compatibility of low voltage devices as established by the British Electrotechnical Committee.

Claims

1. An electrical lamp unit comprising a base part and an illuminating part, the base part incorporating a battery to provide electrical energy for the illuminating part, in which clip means are attached to the base part.

2. A lamp unit according to claim 1 in which the clip means includes a resilient biassing means and a set of jaws, the resilient biassing means acting to urge the jaws together.

3. A lamp unit according to claim 1 or claim 2 in which the illuminating means comprises a part of at least one fibre optic cable.

4. A lamp unit according to claim 1 or claim 2 in which the illuminating means comprises an incandescent bulb.

5. A lamp unit according to claim 4 in which the bulb has at least one filament, and is adapted to flicker.

6. A lamp unit according to claim 3 or claim 4 in which the lamp unit is designed to flash intermittently.

7. A lamp unit according to claim 6 which includes microchip and a capacitor.

8. A lamp unit according to claim 7 in which the battery, microchip and capacitor are all located in the base part.

9. A lamp unit according to any preceding claim in which the base part is designed to simulate a small candle.

10. A lamp unit according to any preceding claim in which the battery is a "AAA" battery.

11. A lamp unit according to any preceding claim in which the base part includes switch means for selectively connecting and disconnecting the electrical circuit to the illuminating means.

12. A lamp unit according to any preceding claim in which the clip means is adjustably attached to the base part.

13. A lamp unit constructed and arranged substantially as described with reference to Fig.l or Fig.2 or Figs 3 and 4 of the accompanying drawings.