WO1998031042A1

WO1998031042A1 - Discharge lamp

Info

Publication number: WO1998031042A1
Application number: PCT/GB1998/000040
Authority: WO
Inventors: Michael Rollin Burn
Original assignee: Light Years Ahead Ipr Limited
Priority date: 1997-01-10
Filing date: 1998-01-07
Publication date: 1998-07-16
Also published as: GB9700426D0

Abstract

There is disclosed an electrical discharge lamp comprising an envelope (12) of glass containing a driver (13) for a gas discharge tube and attached to an insert (14) for an electric socket outlet, the glass envelope (12) including within its thickness a gas discharge tube (15) connected to the driver (13).

Description

DISCHARGE LAMP

This invention relates to light sources, more particularly, but not exclusively, to light sources such as are used for illumination in domestic and commercial environments.

Essentially two kinds of illuminant are used nowadays, namely incandescent bulbs, invented over a century ago, and fluorescent tubes. Incandescent - tungsten - bulbs, whose range has more recently been extended by quartz-halogen embodiments giving extra brightness, are more versatile than fluorescents, being generally smaller and adapted to wide variation in form and colour. Fluorescents, however, are more energy- efficient by an order of magnitude. A principal drawback is that, being tubular in nature, they tend not to be form-adaptable; generally speaking, fluorescent tubes are long and straight, though some "circular" tubes are available and, in recent years, compactly folded tubes have "simulated" incandescent bulbs, inasmuch as they approximate somewhat to the shape and size of incandescents.

It is probably true to say that not only at the present time but also for many years to come the vast majority of domestic and commercial luminaries and light fittings will accept one or the other standard type of light bulb fitting, namely bayonet or screw thread. Fluorescents cannot be used in either fitting and need special fitments, or adapters.

The present invention provides fluorescent (or gas discharge) lighting that is more versatile than hitherto and which can more effectively simulate the incandescent illuminants that have come to be the more acceptable form of lighting over the years. However, beyond this, the versatility of the lighting of the invention is such as will enable designers to have a more or less free rein in devising new lighting concepts adapted to domestic and commercial interiors of the future.

The invention comprises an electrical discharge lamp comprising an envelope of glass containing a driver for a gas discharge tube and attached to an insert for an electric socket outlet, the glass envelope including within its thickness a gas discharge tube connected to the driver.

The insert may be a standard bayonet or screw type insert.

The discharge tube may be formed between inner and outer layers of the envelope, and may be formed by a mating ridge and depression arrangement in inner and outer layers of the envelope.

The discharge tube may extend substantially beneath the entire surface of the envelope.

The ends of the discharge tube may have hot or cold electrodes.

The envelope may be globular and, with the insert, totally enclose the driver.

The envelope may be made in two parts fused together at assembly with the driver and insert.

The discharge tube may be filled with a selected gas. Embodiments of electrical discharge lamps according to the invention will ow be described with reference to the accompanying drawings, in which :

Figure 1 is a cross-section through a first embodiment;

Figure 2 is a view of the outside of the embodiment of Figure 1 ;

Figure 3 is a cross-section through inner and outer layers of half of the envelope of the embodiment of Figure 1 ; and

Figure 4 is a view of the two halves of the envelope of the embodiment of Figure 1 coming together on assembly with the driver.

The drawings illustrate an electric discharge lamp 11 comprising an envelope 12 of glass containing a driver 13 for a gas discharge tube and attached to an insert 14 for an electric socket outlet, the glass envelope 12 containing within its thickness a gas discharge tube 15 connected to the driver 13.

The insert 14 is a standard bayonet type insert that fits the majority of British light fittings, but could be, of course, a standard American or Continental screw type insert.

The discharge tube 15 is formed by a ridge and depression arrangement in inner and outer layers 16, 17 of the envelope 12. For simplicity, Figure 1 shows only a simple loop of tube 15, though a more complicated sinuous formation is indicated on Figure 2. For simplicity, again, in Figure 3 only the inner layer 16 is shown as having ridges 18 and depressions 19, the ridges 18 contacting the smooth inner face 17a of the outer layer 17 on assembly together, the depressions 19 forming, then, the discharge tube 15 when the two layers are fused together.

To make best use of the materials, i.e. to give the brightest illumination for the size of the lamp, it is desirable that the surface area of the envelope 12 be as fully utilised as possible by having the discharge tube 15 extend substantially beneath the entire surface of the envelope 12 - a sinuous arrangement in which the tube 15 extends from bottom to top of one half of the envelope with a single connection to a similar arrangement in the other half of the envelope would be appropriate, as seen in Figure 3 which shows only one half of the envelope 12, the other half being similar - for simplicity's sake, Figure 3 shows only a modestly sinuous tube 15. It should be remembered that the longer the tube, the higher the wattage, the greater the light output.

Figure 4 shows the two halves of the envelope 12 coming together with the driver 13 and insert 14 - already constructed as a unit with the driver 13 which has terminals 13a to receive terminals 15a of the tube 15, which have been installed and sealed after mating the inner and outer layers 16, 17. The electrodes can be hot or cold cathode type depending on the driving method chosen.

Once together, the two halves of the envelope 12 are fused together and to the insert 14. This can be carried out in an atmosphere of the gas selected for filling the tube 15 at the appropriate pressure.

While a substantially globular envelope 12 has been described totally enclosing the driver 13, it will be appreciated that this is described to demonstrate how a conventional tungsten filament bulb may be approximated. In fact, there are few constraints on design using the techniques described above - the envelope could be of almost any desired shape and size, and it may, but need not totally enclose the driver - not totally enclosing it may lead in some cases to simpler manufacturing procedures.

Claims

1. An electrical discharge lamp comprising an envelope of glass containing a driver for a gas discharge tube and attached to an insert for an electric socket outlet, the glass envelope including within its thickness a gas discharge tube connected to the driver.

2. A lamp according to claim 1, in which the insert is a standard bayonet or screw type insert.

3. A lamp according to claim 1 or claim 2, in which the discharge tube is formed between inner and outer layers of the envelope.

4. A lamp according to any one of claims 1 to 3, in which the discharge tube is formed by a ridge and depression arrangement in inner and outer layers of the envelope.

5. A lamp according to any one of claims 1 to 4, in which the discharge tube extends substantially beneath the entire surface of the envelope.

6. A lamp according to any one of claims 1 to 5, in which the ends of the discharge tube are fitted with electrodes.

7. A lamp according to claim 6, in which the electrodes are hot electrodes.

8. A lamp according to claim 6, in which the electrodes are cold electrodes.

9. A lamp according to any one of claims 1 to 8, in which the envelope is globular and, with the insert, totally encloses the driver.

10. A lamp according to claim 9, of which the envelope is made in two parts fused together at assembly with the driver and insert.

11. A lamp according to any one of claims 1 to 10, in which the discharge tube is filled with a selected gas.