WO2007123491A1

WO2007123491A1 - An electric light

Info

Publication number: WO2007123491A1
Application number: PCT/SG2007/000112
Authority: WO
Inventors: Daniel Muessli
Original assignee: Daniel Muessli
Priority date: 2006-04-21
Filing date: 2007-04-20
Publication date: 2007-11-01
Also published as: SG136820A1

Abstract

In a preferred embodiment of the present invention, an electric light (10) including a fluorescent lamp (12), a base (19) connected to the lamp (12), a light transmissible housing (26) enclosing the lamp (12), and a number of elastomeric spacers (32,33,34) are disclosed herein. The elastomeric spacers (32,33,34) are attached to various parts of the fluorescent lamp (12) to space the lamp (12) from the housing (26).

Description

AN ELECTRIC LIGHT

Background and Field of the Invention

This invention relates to an electric light, more particularly but not exclusively, to a fluorescent lamp.

A fluorescent lamp is often preferred over an incandescent lamp because a fluorescent lamp consumes less electricity and thus saves energy. Conventionally, a fluorescent lamp comprises two opposing electrodes disposed within and at respective ends of an elongate sealed glass tube containing gas and works on the principle of passing electrons between the electrodes through the gas from one end to the other end of the tube to produce light. However, the brightness of a fluorescent lamp is dependent on the length of the tube and thus a fluorescent lamp is usually larger than an incandescent light bulb.

In recent years, improvements have been made to reduce the size of the fluorescent lamp and Compact Fluorescent (CFL) tubes were developed. Such a tube comes in various shapes such as spiral shape or U-shape etc, so as to be as compact as possible while maintaining a certain level of brightness since the length of the tube is not reduced but oriented in a different manner. Also, the fluorescent lamp includes a base comprising a tube holder to support ends of the fluorescent tube and for receiving an electronic ballast to ignite the tube. It is normal to include a glass housing, which may be similar in shape to an incandescent light bulb, to enclose the fluorescent tube,. However, the conventional arrangement of the tube and tube holder leads to higher manufacturing costs. Further, since the holder is disposed at the base, some of the light from the fluorescent tube is blocked.

WO 2005/099360 proposed an electric light having a fluorescent lamp enclosed within a light housing.^' The electric light has a single length of U-shaped wire arranged to support the fluorescent lamp from the light housing, instead of using a tube holder to support the lamp from the base. Without the tube holder, such an arrangement reduces manufacturing and product costs and it also allows more light from the lamp to be projected over a greater area since the tube holder is normally opaque. However, the contact or close proximity between the U-shaped wire and the lamp is prone to abrasion, especially during transportation. Also, the wire is likely to cause shadows when the lamp is in use.

It is an object of the present invention to provide an electric light which addresses at least one of the disadvantages of the prior art and/or to provide the public with a useful choice.

Summary of the Invention

In general terms, the present invention relates to an electric light comprising an arc lamp, a lamp housing receiving the arc lamp, and an elastomeric spacer arranged to space the arc lamp from the lamp housing. In a first aspect of the invention, there is provided an electric light comprising an arc lamp having a light emitting element; a light transmissible housing receiving the arc lamp; a base connected to the arc lamp and being arranged to connect a power source to the light emitting element; and one or more elastomeric spacers attached to the arc lamp and arranged to space the arc lamp from the housing.

An arc lamp (or a discharge lamp) produces light by using an electrical arc running through a gas plasma and the terms are used broadly in this application to include high pressure arc lamps such as mercury vapour lamps, high pressure sodium arc lamps and metal halide arc lamps etc, and low pressure arc lamps such as fluorescent lamps etc.

As described in the preferred embodiment, the present invention has an advantage of using the elastomeric spacers to support the arc lamp in a desired position, preferably upright, and in a non-abrasive manner. This arrangement obviates a need for a conventional lamp holder disposed at the base or use of an inverted U-shaped resilient wire to support the arch lamp from the housing. Consequently, this helps to reduce the manufacturing cost of the electric light.

Also without the lamp holder, which is normally made of opaque plastic, the light emitted from the lamp can thus be projected over a greater area than in a conventional arrangement. Preferably, thθ one or more spacers are transparent so that there is no shadow created when the electric light is in used. The one or more spacers may be attached to the arc lamp and the housing using adhesives. Alternatively, if the spacers are formed from adhesive materials such as silicon adhesives, then the spacers already have the adhesion properties for attaching to the arc lamp.

Advantageously, the electric light further comprises means for urging the arc lamp towards the one or more spacers. Preferably, the electric light comprises an ignition circuit mounted to a circuit board and the urging means comprises the circuit board, and which may protrude from the base. For a neater arrangement, the circuit board is preferably arranged between two ends of the arc lamp. Further, to provide better urging, the circuit board may support at least one length of resilient wire for urging the arc lamp.

Preferably, the one or more elastomeric spacers are formed from silicone gel.

Specifically, the arc lamp may be in the form of a tubular fluorescent lamp. It is envisaged that the light emitting element may come in various shapes and sizes, such as spiral shape, so that the lamp can be as compact as possible. Similarly, the housing can be in any desired shape, such as bulb or bullet shape.

The arc lamp may be in the form of a high pressure arc lamp, which may be a mercury vapour arc lamp. Brief Description of the Drawings

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings in which,

Figure 1 is a perspective view of an electric light comprising a fluorescent lamp, elastomeric spacers, and a light housing (only half shown), according to a preferred embodiment of the present invention;

Figure 2 shows the electric light of Figure 1 and the other housing half and with the fluorescent lamp disengaged from a screw cap; and

Figure 3 is an enlarged view of certain parts of the electric light of Figure 1.

Detailed Description of the Preferred Embodiment

Figure 1 illustrates a perspective view of an electric bulb 10 according to a preferred embodiment of the present invention. The electric bulb 10 comprises an arc lamp which in this embodiment is in the form of a spiral fluorescent lamp 12 having two ends 12a,12b (only one end is shown in the figures) connected to an ignition circuit 14 that is arranged to ignite the fluorescent lamp 12. The ignition circuit 14 has a printed circuit board (PCB) 14a connected to the two ends 12a, 12b of the fluorescent lamp 12 via conductive legs 16,18. The electric bulb 10 has a base 19 including a conductive screw cap 20 arranged to connect a power source electrically to the fluorescent lamp 12 via the ignition circuit 14. The screw cap 20 has a cavity 21 which receives part of the ignition circuit 14 (see Figures 1 and 2). The screw cap 20 also has a threaded body 22 and a contact base 24, and is arranged to be secured to a standard light bulb socket without modification.

It would be apparent that the configuration of the lamp 12 which includes a light emitting element 12c is well known and thus no further description is needed. Also, the ignition circuit 14 used to ignite the lamp 12 is conventional and thus details are not described here. However, it would be appropriate to add that the ignition circuit 14 may include a starter, an electronic ballast (in the case of a "self-ballasted" fluorescent lamp) and other components necessary to ignite the lamp 12. In this embodiment, the PCB 14a is arranged in an upstanding manner so that the PCB 14a is arranged between the two ends 12a, 12b of the fluorescent lamp, thus supporting the fluorescent lamp and this will be described in more detail below.

The light 10 also includes a light transmissible lamp housing 26 which receives, and preferably encloses fully the light emitting element 12c of the fluorescent lamp 12 and Figure 1 shows the housing 26 in part to show the internal components. In this embodiment, the housing 26 is in a standard bulb shape and may be made of glass or acrylic depending on the application. It is also envisaged that the housing 26 may be in other shapes, for example globe or bullet shape, and this is normally dependent on the shape of the fluorescent lamp 12 as well.

As shown in the figures, the light blub 10 includes a plurality of elastomeric spacers 30,32,34 which are selectively attached at different parts of the fluorescent lamp 12 to space the lamp from the housing 26 and to provide the necessary cushioning. The arrangement of the PCB 12 is also unconventional since, as explained earlier, the PCB 14a is arranged upstanding and between the ends of the fluorescent lamp 12. This is so that the raised PCB 12c is arranged to urge the lamp 12 towards the end of the housing furthest away from the base 13, and together with the elastomeric spacers, hold the lamp 12 fixedly in place. Such an arrangement means that light bulb 10 can accommodate a larger PCB and thus, lower cost components (which are usually larger in size compared to the more expensive ones performing the same functions) can be used for the ignition circuit 14. In this way, the product costs of the light bulb can be reduced further since lower cost components can be used for the ignition circuit.

As shown more clearly in Figure 3, the light bulb 10 also includes two resilient length of wires 36,38 arranged substantially as a cross and mounted to an edge of the PCB 14a so that the longitudinal axes of the wires are more or less tangential to the vertical plane of the PCB 14 so that the wires 36,38 engage the fluorescent lamp 12. With this arrangement, the PCB 14 supports the lamp 12 in a more secured manner thus reducing movement of the lamp 12. In the present embodiment, each of the elastomeric spacers 30,32,34 is transparent and formed from silicon gel. However, other suitable elastomeric materials such as silicon rubber or silicon adhesives can also be used. The elastomeric spacers act as flexible and resiliently deformable cushions to dampen any movement of the fluorescent lamp, for example during transportation. The transparency of the silicon gel is advantageous as it does not create shadows when the lamp 12 is turned on.

The elastomeric spacers 30,32,34 are attached to the lamp 12 using adhesives but if silicon adhesive is used to form the spacers, then there is no need for additional adhesives.

In the present embodiment, the housing 26 comprises two halves 26a, 26b as shown in Figure 2 which facilitate easier assembly of the electric light 10 and which are adhered together using suitable adhesives. To facilitate easier closure, the housing 26 includes two pairs of guiding elements in the form of male studs 40a-40d formed at the rim of one housing half 26a and corresponding female openings (not shown) formed at the rim of the other housing half 26b. The housing 26 further comprises flanges 42,44 extending from the two halves 26a,26b which are arranged to engage the cavity walls of the screw cap 20. In this way, a compact electric light 10 can be formed which alleviates a separate means for connecting the housing 26 and the screw cap 20 to the electric light 10. The described embodiment should not be construed as limitative. For example, it should be apparent that the present invention also extends to other types of arc lamps for example, mercury vapour arc lamps and high pressure arc lamps, not just to a fluorescent lamp 12. Further, the fluorescent lamp 12 may be in other shapes and sizes and not necessary spiral. Also, the PCB 14a of the ignition circuit 14 may not be necessarily protruding above the screw cap 20 but instead can be hidden inside the cavity 21 of the screw cap in a usual way, and the wires 36,38 are also not necessary. However, to support the fluorescent lamp in a desired "floating" position, more elastomeric spacers can be used as those shown in broken lines (i.e. 46,48). Alternatively, biasing means such as a spring member, can be used to bias the lamp 12 towards the elastomeric spacers 30,32,34, particularly if the ignition circuit 14 is not integrated with the electric bulb 10. In a further alternative, instead of a few spacers, only one spacer, that is relatively large in size, and selectively located to space and cushion the lamp from the housing, can be used, particularly for smaller electric bulbs.

Further, the base 19 can be in other shapes and sizes with the screw cap 20 replaced by other electrical connection means adapted to connect the electric light 10 to other types of light sockets (eg. pin types).

Although it is described that the housing 26 is formed from two housing halves 26a,26b, this may not be necessary so. Further, in the described embodiment, the housing 26 is halved in a vertical manner but this may not be necessarily so since the housing 26 can be halved in a horizontal manner i.e. creating top and bottom halves.

Two wires 36,38 arranged as a cross are used in the described embodiment but depending on applications, one or more than two wires may be suitable.

Having now fully described the invention, it should be apparent to one of ordinary skill in the art that many modifications can be made hereto without departing from the scope as claimed.

Claims

1. An electric light comprising an arc lamp having a light emitting element; a light transmissible housing receiving the arc lamp; a base connected to the arc lamp and being arranged to connect a power source to the light emitting element; and one or more elastomeric spacers attached to the arc lamp and arranged to space the arc lamp from the housing.

2. An electric light according to claim 1 , wherein the one or more spacers are transparent.

3. An electric light according to claim 1 or 2, wherein the one or more spacers are attached to the arc lamp and the housing using adhesives.

4. An electric light according to claim 1 or 2, wherein the one or more elastomeric spacers include adhesives for attaching to the arc lamp.

5. An electric light according to any of the preceding claim, further comprising means for urging the arc lamp towards the one or more spacers.

6. An electric light according to claim 5, further comprising an ignition circuit mounted to a circuit board for igniting the arc lamp, wherein the urging means comprises the circuit board.

7. An electric light according to claim 6, wherein the circuit board protrudes from the base.

8. An electric light according to claim 5 or 6, wherein the circuit board is arranged between two ends of the arc lamp.

9. An electric light according to any of claims 5 to 7, wherein the circuit board supports at least one length of resilient wire for urging the arc lamp.

10. An electric light according any of the preceding claim, wherein the one or more elastomeric spacers are formed from silicone gel.

11. An electric light according to any of the preceding claim, wherein the arc lamp is in the form of a tubular fluorescent lamp.

12. An electric light according to claim 9, wherein the fluorescent lamp is spiral shape.

13. An electric light according to any of claims 1 to 10, wherein the arc lamp is in the form of a high pressure arc lamp.

14. An electric light according to claim 11, wherein the high pressure arc lamp is a mercury vapour arc lamp.