WO1996021126A1

WO1996021126A1 - A gas fire

Info

Publication number: WO1996021126A1
Application number: PCT/NZ1996/000001
Authority: WO
Inventors: Werner Johannes Janssens
Original assignee: West Glen Industrial Coatings Limited
Priority date: 1995-01-05
Filing date: 1996-01-04
Publication date: 1996-07-11
Also published as: AU4319196A; CA2209679A1

Abstract

A gas fire (1) includes one or more artificial fuel elements (18). At least one, and usually all of the artificial fuel elements (18) contain therein a plenum chamber (20). A gas supply through line (21) is provided to the plenum chamber (20), to supply substantially unaerated fuel gas thereto. The artificial fuel element (18) is comprised of, or has areas comprised of a porous material.

Description

A GAS FIRE

TECHNICAL FIELD OF THE INVENTION

This invention relates to a gas fire and is applicable particularly, but not exclusively to a gas fire incorporating a simulated log of wood.

BACKGROUND ART

Many attempts have been made to devise a gas fire which resembles a fire burning solid fuels, such as logs. To date no realistic solid fuel fire simulation has been achieved by gas fires built to resemble a solid fuel fire. In particular, the flames in the simulated solid fuel fire are statically positioned or in addition, are barely visible.

OBJECT

It is therefore an object of the present invention to provide a gas fire which will produce an improved visual effect, or will at least provide the public with a useful choice.

DISCLOSURE OF THE INVENTION

Accordingly, in one aspect the present invention consists in a gas fire including one or more artificial fuel elements, at least one of the artificial fuel elements containing therein a plenum chamber, a gas supply to the plenum chamber to supply substantially unaerated fuel gas and the artificial fuel element being comprised of, or having areas comprised of a porous material, preferably a plurality of artificial fuel elements are provided.

Preferably, substantially the whole of each artificial fuel element is of porous material.

Preferably said artificial fuel element is formed from compressed incombustible fibre material. Preferably the external surface of the artificial fuel elementis in the shape and appearance of a partly burnt wooden log.

Preferably the heat output from each artificial fuel element is low.

In a further aspect the invention consists of an artificial fuel element, the artificial fuel element containing therein a plenum chamber, a connection to receive in use a gasline plenum chamber to supply substantially unaerated fuel gas, to the plenum chamber and the artificial element being comprised of, or having areas comprising of a porous material.

Preferably substantially the whole of the artificial fuel element is of porous material.

Preferably the artificial fuel element is formed from compressed incombustible fibre material.

Preferably the external surface of the artificial fuel element is in the shape and appearance of a partly burnt wooden log.

BRIEF DESCRIPTION OF THE DRAWINGS

One preferred form of the invention will now be described with reference to the accompanying drawing in which,

Figure 1 is a diagrammatic side cross-section of a gas fire including a diagrammatic representation of the invention.

Figure 2 is adiagrammatic cross-section of artificial fuel elements and the gas supply thereto as used in the invention, and

Figure 3 is a longitudinal cross-section of one form of artificial fuel element usable in the invention.

BEST MODES FOR CARRYING OUT THE INVENTION Referring to the drawings, a gas fire (1) is provided which has an external casing formed by top (2), a back (3), a bottom (4), a front door (5) and a grill (6) through which heated air may pass. The construction includes a flue (7) and pipes (8) through which air may pass to be heated to pass outwardly through the grill (6). Air can also pass through the upper parts of the fire heating chamber(16), through passage ways at (10). These parts are substantially well known. Heating elements (15) are provided towards the bottom rear of the heating chamber (16) and a gas air mixture is supplied to the heating elements (15) to provide the main heat output of the fire. Towards the bottom front of the fire, artificial fuel elements (18) are provided which may take the form of partly burnt imitation logs. Of course other fuel elements such as coal could be provided. It is desired that the heat output from the artificial fuel elements (18) be relatively low, being for example of the order of 1.5 kilowatts. Thus the burning gas about the simulated logs (18) does not contribute significantly to the heat output of the construction.

If desired, a simulated ash bed of, for example, vermiculite, may be positioned where it best achieves the desired aesthetic effect.

The simulated fuel elements (18) may be formed from any suitable material and for example, may be formed from a compressed incombustible fibre material such as "rock wool". If desired a rigidised ceramic material may be used in conjunction with or in place of the "rock wool", the porous outer body may be formed for example, by compressing "rock wool" with some combustible material such as grass clippings mixed therein. Once set or cured, the grass clippings or other combustible material can be burned away leaving relatively small passageways randomly through the imitation fuel element. The aim is to have a random density of passageways of about one passageway per square centimeter.

The plenum chamber is perforated for example by drilling or again by providing combustible material and a satisfactory effect can be achieved by providing such perforations (19) at about 30 mm spacings and each passageway may have a diameter of, for example, about 4 mm.

Within the simulated fuel element is a plenum chamber (20) which is fed by a gas line

(21), attached to a suitable connector. The gas lines (21) may be formed by branches from a common line (22). Valves such as valves (23) may be provided to adjust the flow of gas to the plenum chambers (20), and the valves for example may vary the effective aperture size of the entrance to the branch lines (21). Other valving arrangements can be used. One or more support legs (25) can be provided as necessary. It is of particular importance to the invention that the gas supply through the lines (22) and (21) to the plenum chambers (20), be substantially unaerated gas. If possible the gas supply should be totally unaerated so that when burning a visible yellow flame can be achieved. The gas supplied to the plenum chamber (20) will of course be under the normal supply pressure.

Of course the porosity could be achieved by a sleeve or cover over a substantially more permeable centre portion about the plenum chamber, or if desired only some areas of the wall of the fuel element could be provided with the porosity.

In use the burners (15) are used substantially in the known manner to provide the principal heating effect. A pleasing visual effect is obtained from the burners formed by the fuel elements (18). Gas, which is substantially unaerated, passes through the pores of the artificial fuel elements from the plenum chamber (20) achieving a substantially dispersed effect over the surface of the artificial fuel element where burning takes place. There is a little heat output from this burner which is provided substantially for decorative effect only. Any air movement within the chamber (16) will give a fluctuating appearance to the visible flames.

The visual effect given by the gas fire of the invention is substantially enhanced over known constructions principally because the fuel element such as the artificial log simulates to a greater extent than hitherto known, the actual situation with a typical log. In particular the flame effect on the surface of a burning log is largely achieved from gas emissions from within the log, which gases escape through fissures and cracks and the effect of porosity in the log itself. That is to say the flames appear to emanate from the interior of the log. In the invention described this effect is again achieved as the gas comes from the interior of the log over a dispersed porosity, thus achieving an effect similar to that of burning real life log.

A flame failure means may be provided to detect absence of combustion of the gas fed to the burn, and the flame failure means is desirably connected to cut off the gas supply to the simulated fuel element and the gas burner upon operation. The detection element may be responsive to heat from the heat burners (15) being connected to a gas valve. The gas valve is connected in the gas supply pipe feeding the gas supply pipes to the burners (15) and (18). If the gas supply in pipe (25) is interrupted the cooling of the detection element will turn off the valve.

Finally it will be appreciated that various other alterations or modifications may be made to the foregoing without departing from the scope of this invention as set forth in the following claims.

Claims

CLAIMS:

1. A gas fire including one or more artificial fuel elements, at least one of the artificial fuel elements containing therein a plenum chamber, a gas supply to the plenum chamber to supply substantially unaerated fuel gas and the artificial fuel element being comprised of, or having areas comprised of a porous material.

2. A gas fire as claimed in claim (1) wherein a plurality of artificial fuel elements are provided.

3. A gas fire as claimed in claim 1 wherein substantially the whole of each artificial fuel element is of porous material.

4. A gas fire as claimed in claim 1 , wherein said artificial fuel element is formed from compressed incombustible fibre material.

5. A gas fire as claimed in claim 1, wherein the external surface of the artificial fuel element is in the shape and appearance of a partly burnt wooden log.

6. A gas fire as claimed in claim 1 , wherein the heat output from each artificial fuel element is does not contribute significantly to the heat output of the fire.

7. An artificial fuel element, the artificial fuel element containing therein a plenum chamber, a connection to receive in use a gas line to plenum chamber supply substantially unaerated fuel gas to the plenum chamber and the artificial element being comprised of, or having areas comprised of a porous material.

8. An artificial fuel element as claimed in claim 7, wherein substantially the whole of the artificial fuel element is of porous material.

9. An artificial fuel element as claimed in claim 7, wherein said fuel element is formed from compressed incombustible fibre material.

10. An artificial fuel element as claimed in claim 7, wherein the external surface of the artificial fuel element is in the shape and appearance of a partly burnt log.