GB2197064A - Simulated solid fuel gas fires - Google Patents

Abstract

A simulated solid fuel gas fire has a first aerated gas burner (13) and a second non-aerated or lightly aerated gas burner (14) for producing decorative flames about a non-burning fuel representation. A control valve (25) provides a plurality of heat output settings to both the burners. At lower heat outputs the fuel representation is not heated sufficiently to glow red. At lower settings, therefore, an increased gas supply is provided to the second burner so that the decorative flames are larger. At higher settings the fuel representation glows red, so that a more realistic burning appearance is given. At these settings the supply to the second burner is reduced so that the decorative flames are smaller. The valve (25) is arranged to provide this inverse gas flow relationship to the two burners as the overall heat setting is altered. <IMAGE>

Description

SPECIFICATION Gas fires This invention relates to gas fires of the kind in which a realistic representation of a solid fuelburning fire is made by having non-aerated or lightly aerated flames playing about a noncombustible fuel simulation.

The invention provides a gas fire having a first burner for aerated gas, a second burner for non-aerated or lightly aerated gas, a non-combustible fuel simulation in the path of flames from both burners and control means for the supply of gas to both burners, providing two or more settings in which an increased supply of gas to the first burner is associated with a decreased supply of gas to the second burner.

It is found that when an aerated gas burner is turned to a low setting at which a low gas input is used such that the fuel simulation does not glow red, the representation loses its appearance of reality. According to the invention this is compensated by arranging the control means so that the non-aerated gas burner has its maximum input at this low setting. At settings at which the fuel simulation may be expected to glow, the supply to the non-aerated gas burner is reduced.

It will be understood that the heating efficiency achieved by the aerated gas burner is potentially higher than that achieved by the non-aerated burner. Moreover, the non-aerated burner flame tends to deposit soot. Thus, the non-aerated burner, although it improves the appearance, does not improve the performance of the fire. According to the invention, therefore, the use of the non-aerated flame has been concentrated at the low setting where it will be most effective, while its use has been reduced at higher settings where it is less necessary, thus reducing overall any adverse effects of the non-aerated flame.

Preferably the control means comprises a duplex valve, manual adjustment of which achieves the inversely related flows of the two burners automatically. The valve may be a plug valve rotatable between four settings at each of which the two burners are supplied with inverselyrelated gas flows as set out above.

The invention also extends to a valve adapted for use in a- gas fire and providing two gas supplies in which increased flow on one supply line is accompanied by decreased flow on the other. There may be another valve in the supply to the non-aerated burner which can be manually operated to reduce the flows controlled by the first valve, but not, of course, to increase them.

A specific embodiment of the invention is shown in the accompanying drawings, in which: Figure 1 is a diagrammatic side view of a gas fire, Figures 2a and 2b are illustrations of flames of the gas fire of Fig. 1 at different settings, Figure 3 is a diagram showing the gas controls of the fire of Fig. 1 in front view, and Figure 4 is a diagrammatic representation of the operative parts of the control valve.

Referring first to Fig. 1, the gas fire has a glass front panel (11) through which is viewed a non-burning representation of coals, coke or logs (12). Two burner bars (13, 14) direct flames through openings in the representation so that when it is heated sufficiently it glows red and radiates heat, the flames when visible adding to the impression that the representation is burning.

The front bar (13) of the two burners is of the kind having a series of closely spaced openings supplied with fully aerated gas or substantially fully aerated gas by conventional means.

Its flame (15) (Fig. 2) is directed rearwardly and upwardly at an angle of about 40 to the horizontal. The back burner bar (14) is supplied with unaerated or lightly aerated gas such that its flame (16) is floppy and yellow. The back burner bar (14) is located closely adjacent the front burner bar (13) so that at some settings the flames interact. Bar (14) has a smaller number of irregularly spaced openings, e.g. 5 or 7 openings, giving the appearance of irregular real'fire flames. The openings in the coal representation (12) are carefully located with respect to the floppy flames so that they may pass therethrough in a realistic manner.

Referring now to Fig. 3, the two burner bars (14) and (13) are shown with respective gas injectors (20) and (21) connected to gas lines (22) and (23). A manually-controlled multifunction gas valve (25) is connected to both gas lines (22) and (23) and to a gas supply line (26). The valve (25) has a plug (not shown) rotatable by manual knob (27) between different rotary settings. As the plug is rotated it opens or closes selected connecting ducts between gas inlet (26) and the outlets (22) and (23). The dimensions of the connecting ducts are such that the gas flows on outlets (22) and (23) are varied. Thus the flow to the aerated burner (13) is increased by incremental steps while the corresponding flow to the non-aerated burner (14) is, altered in relation to those steps as described hereinafter.

In a preferred gas valve, there are four stepped positions for knob (27) at which positions four discrete gas flows are achieved. Examples of suitable flows are as follows: Settling. In ut to Aerated Input to Non-Aerated Total Heat P ~ P Burner BThU . Burner (BThU). Output.

1 5,000 5,000 1* KW 2 8,000 4,500 2 KW 3 10,500 3,750 2* KW 4 14,000 3,000 3 KW At setting 1 the aerated burner has its lowest input. At this rate the flames are short and blue and the coal representation (12) is not heated enough to glow red, although it does radiate heat.

Thus the fire would look dead if were not for the non-aerated flames. At this setting the nonaerated burner (14) has its largest input and large floppy yellow flames are produced, giving a highly decorative flame picture even without the red flow. This setting is illustrated in Fig. 2a, from which it will be seen that the flames (15) from the burner (13) are too small to have any substantial effect on the floppy flames (16) which extend approximately vertically adjacent the front of the fire and pass through the purpose designed openings in the front of the fuel effect.

At the other end of the range at setting 4, the aerated burner has its highest input so that its flames are large and blue and the coal representation (12) is heated to glow red. Thus the floppy flames are less important in rendering the fire more lifelike. At this setting the nonaerated burner (14) has its lowest input and thus shorter floppy yellow flames are produced than at setting 1. Setting 4 is illustrated in Fig. 2b in which it will be seen that the flames (15) from burner (13) are large enough to affect the floppy flames which are bent over to extend with the aerated flames. The increased momentum of the aerated flames magnifies the reduced decorative non-aerated flames to enhance the flame picture. At this setting the temperature is sufficient to burn off most of the soot deposits which may have been made by the floppy flames at other settings.

At intermediate settings 2 and 3 there are increasing heat inputs to burner (13) and decreasing inputs to burner (14), so that the flame conditions intermediate those shown in Figs. 2a and 2b are achieved.

The valve (25) is used in conjunction with an auxiliary manually-controlled valve (30) connected in supply line (22) for burner (14). The fire may therefore be operated with no flickering flames if desired by turning this valve off, or reduced flames by partially closing the valve. The operation of main valve (25) is to reduce the flow to the valve (30) at the higher setting so that its output is reduced.

The operation of the main valve (25) is illustrated in Fig. 4. This is a duplex gas tap with a plug having a plurality of holes arranged in two banks. One bank (33) supplies the aerated burner (13) and has four different sized holes, each corresponding to the desired flow rate at a corresponding setting. As the plug is turned a selected one of the holes is connected to an outlet to burner (13). The other bank (34) supplies the non-aerated burner (14) and comprises a hole at setting 1, and a smaller hole at setting 2 connected to a shallow gallery (35) extending across settings 2, 3 and 4. The reduction in gas rate for settings 3 and 4 is achieved by the additional pressure loss due to the gas flowing along the gallery to reach the outlet to burner (14).

A flame failure device (31) operates to cut off the gas supply at (32) when no flame is detected after a predetermined time from turning on by the knob (27).

Claims (10)

1. A gas fire having a first burner for aerated gas, a second burner for non-aerated or lightly aerated gas, a non-combustible fuel simulation in the path of flames from both burners and control means for the supply of gas to both burners providing a lowest heat output setting and at least one higher heat output setting in which an increased supply of gas to the first burner is associated with a decreased supply of gas to the second burner.

2. A gas fire as claimed in claim 1, wherein said control means comprises a manually adjustable duplex valve providing for the two gas suply flows, one to the first burner and the other to the second burner.

3. A gas fire as claimed in claim 2, whereinsaid valve is a pug valve, rotatable between said settings.

4. A gas fire as claimed in any of claims 1 to 3, wherein there are four settings in which the first burner receives successively increased supplies of gas while the second burner receives successively decreased supplies of gas.

5. A gas fire as claimed in any of claims 1 to 4, wherein the first, lowest heat output, setting allows for gas flows such as to provide a 5000 BThU heat output from the first burner and a 5000 BThU heat output from the second burner and another, highest setting, allows for gas flows such as to provide a 14,000 BThU heat output from the first burner and a 3000 BThU heat output from the second burner.

6. A gas fire as claimed in any of claims 1 to 5, wherein said non-combustible fuel simulation when heated sufficiently glows red, the total heat output at said first lowest heat output setting being insufficient to cause it to glow while at higher heat output settings the total heat output is sufficient to cause it to glow.

7. A gas fire as claimed in any of claims 1 to 6, wherein said first burner is a burner bar with regularly spaced gas openings, while the second burner is a burner bar located closely adjacent said first burner and having irregularly spaced openings, the non-combustible fuel simulation being located above the burner bars with openings located to allow flames to appear above the fuel simulation.

8. A gas fire as claimed in claim 7, wherein the flames from the first burner bar are directed rearwardly and upwardly from the front of the fire and across the path of the flames from the second burner bar so that at some higher settings the flames interact.

9. A gas fire as claimed in any of claims 1 to 8, having a further manually-controlled valve whereby the supply to the second burner can be turned down or off independently of the said control means.

10. A gas fire substantially as described hereinbefore with reference to the accompanying drawings.