GB2134649A - Simulated solid fuel fires - Google Patents

Abstract

A heater 1 with gas burner 2 and radiant elements 3 has a display unit 4 to simulate a coal fire. Unit 4 has a grey translucent top cover 5 simulating a bed of coal embers, the cover 5 having six non-uniformly spaced holes over each of which is a hollowed artificial piece of coal 6. Each artificial coal piece 6 has one or more transparent windows 7 through which a flicker-flame lamp 8 can be seen. The lamps 8 are gas discharge lamps having electrodes shaped and arranged to provide an unstable mode discharge and are mounted on a common support plate 10. Two filament bulbs 11, each with an apertured spinner 12, are provided to cast patterns of light and shadow on cover 5 and hence simulate a fluctuating glow; a strip of frosted glass 14 increases scattering of light from bulbs 11. <IMAGE>

Description

SPECIFICATION Flicker flame fire The present invention relates to a display unit for simulating a solid-fuel fire, particularly but not solely for use with a gas or electric heater.

One form of conventional gas or electric heater presently on the market has a unit for simulating a solid-fuel fire in order to enhance the appeal to customers. This unit has a fibre-glass cover shaped and coloured to represent a pile of coals or logs, under which cover are located at least one filament lamp and rotatable apertured disc. Heat rising from the illuminated lamp causes the disc to rotate, whereupon it casts moving patterns of shadows and light onto the inner surface of the cover. Parts of the cover are coloured to transmit orange-yellow light and hence simulate glowing solid fuel, whereas the remainder of the cover substantially prevents light transmission and hence retains its original colouring (thereby simulating solid fuel which is not yet alight).A major disadvantage of this type of simulation unit is that, because the rotation of the disc is substantially uniform, the variation of illumination is regular, resulting in an unrealistic and unsatisfactory illusion detrimental to the overall appearance of the heater.

U.S. Patent No. 4253045 discloses various proposals to vary, apparently in random manner, the illumination cast onto the inner surface of a simulation unit cover, in an attempt to imitate realistically the glowing effect of a solid fuel fire.

An object of the present invention is to provide a display unit which can simulate realistically a solid-fuel fire at a modest cost and in a simple and reliable manner.

The present invention provides a display unit for simulating a solid-fuel fire, the unit comprising a housing having a surface which simulates solidfuel, at least one gas discharge lamp within the housing, the at least one lamp having electrodes shaped and arranged to provide, in use, an unstable mode discharge, at least one window in the simulation surface to enable the lamp to be viewed directly from outside the housing.

The direct viewing of the lamp(s) in unstable mode discharge may be by line-of-sight, whether solely through air or through air and a transparent material; additionaiiy the direct viewing may include reflection. In all cases, the source itself of the randomly moving light must be visible to an observer.

Preferably a substantially transparent section of the simulation surface forms a window.

Additionally or alternatively, an aperture in the simulation surface forms a window.

Two or more of the lamps may be mounted on a common support secured to the housing, thereby ensuring that the lamps are rigidly held in the housing. In an alternative form, a lamp is secured individually to the simulation surface, for example by a member which is embedded within that surface. In either arrangement a lamp can be installed or replaced easily and quickly.

The display unit of the present invention may be used either alone, merely for decorative purposes, or in combination with a heater fuelled, for example, by gas or electricity.

The display unit of the present invention provides simulation of a solid-fuel fire in which the flames themselves can be seen, rather than the prior art units described above which only attempt to imitate the glow of a solid-fuel fire and/or the indirect light from flickering flames. The unit of present invention affords a direct view of imitation flickering flames whose movement is achieved electrically rather than by for example, mechanical means; moreover, the unit of the present invention does not utilize any gas burners to produce gas flames, although of course the unit could be used in a heater which is fuelled by gas.

In order that the invention may more clearly be understood, a description is now given, by way of example only, reference being made to the sole accompanying Figure of a heater with a display unit embodying the present invention.

In the Figure, a heater 1 with a conventional arrangement of gas burner jets 2 and radiant elements 3 incorporates a display unit 4 to simulate a coal fire. The Figure shows a heater 1 with the front of unit 4 out away in order that the interior can be seen.

Display unit 4 has a grey translucent top cover 5 which simulates a bed of coals and of embers; the cover 5 has six non-uniformly spaced holes, over each of which there sits a separate hollow black element 6 to simulate an individual piece of coal. Thus the cover 5 and elements 6 together form a simulation surface. Each element 6 has at least one substantially transparent section forming a window 7 through .which can be seen a flicker-flame lamp 8 positioned within the element 6 near to the window(s) 7. All the lamps 8 are mounted, via standard bayonet holders 9, on a common support plate 10 which is fixed to the housing of heater 1.

The flicker-flame lamps are of a conventional type in which a glass enclosure containing neon has two flame-shaped electrodes, the size of the cathode and the spacing of the electrodes encouraging the discharge to wander over the electrode surfaces in a random manner. This type of lamp has been known widely for many years (see for example British Patent Specification No. 997961 which was published on 14 July, 1965), but there has been no prior disclosure or use of such lamps in a unit according to the present invention as claimed, even though there has been much interest and activity in the industry concerning the development of improved and more realistic simulated solid-fuel fires.

The display unit 4 also has two filament bulbs 11 (only one being in view in the Figure), above each of which there is a spinner 1 2 with apertures 13 in order to cast patterns of light and shadow on the inner surface of cover 5. Located along the back of unit 4 and above part of the spinners 12 is a strip of frosted glass 14 which contributes to the random scattering. of light from bulbs 11.

When the display unit is operating, the randomly moving discharge of lamps 8 can readily be seen through the respective window(s) 7 to give the appearance of real flickering flames, while the fluctuating light produced by bulbs 11, spinners 12 and frosted glass 14 is transmitted through cover 5 to give the appearance of a varying glow. Clearly display unit 14 can be operating whether or not the heater 1 is producing any heat; thus the unit 4 in heater 1 can be used to produce an aesthetically and pleasing display, enhancing the appearance of a room, even when it is not necessary (and indeed may be undesirable, at that time) for the room to be heated.The unit 4 also has a control whereby the bulbs 11 can be switched between an 'off' mode and two different light output settings, so that the overall appearance of the unit can be varied as desired.

The housing of heater 1 has a heat insulating barrier 1 5 which separates the section incorporating the radiants 3 from the display unit 4, because undue heating of lamps 8 and bulbs 11 can adversely affect their operation and longevity. Additionally there may be ducts and/or a fan in the heater in order to promote air circulation around unit 4 in order to minimise the effect on the lamps 8 of heat from radiants 2. In a modified heater, unit 4 is located below the radiants.

The artificial coal pieces 6 are made by forming a transparent plastics material moulding, fixing a mask to the moulding and then applying (for example by spraying) appropriate colouring, so that when the mask is removed the portions remaining transparent form the window(s) 7. The cover also, if desired, can be manufactured in the same way.

A display unit embodying the present invention may include any one or more of the following modifications from the form shown in the sole Figure. The support play may be arcuate such that the lamps 8 are not in the same horizontal plane, and/or it may be twisted about an axis parallel to its longitudinal dimension such that the lamps 8 have different orientations; additionally or alternatively the support bar may be positioned within the unit in such a way that the lamps 8 do not lie in a single horizontal straight line substantially parallel to the back surface of the unit 4.The surface simulating a solid-fuel fire may have at least one aperture through which a flickerflame lamp can be viewed directly, whereby the at least one aperture comprises a window; the apertured surface may be manufactured solely by moulding, or the surface may be manufactured initially without these apertures (e.g. by moulding) and the apertures are cut out subsequently. One or more of the lamps 8 may be individually fixed solely to the simulation surface itself in order to improve the randomness of the positioning of the lamps over the surface; thus, for example, a single lamp may be secured to two wires each with one end embedded in the surface.

The unit may have a dimming control whereby the power input to, and hence the light output of, the lamps 8 can be adjusted as required. The lamps in the unit may be electrically connected in a series arrangement or in a parallel arrangement, or in a combination of each (in the latter case the variation in electrical potential drop across different lamps resulting in a variation in light output and rate of discharge movement between different lamps). One or more of the lamps may have a sleeve to promote scattering of light; the sleeve may include a reflective portion to direct additional light forwards. The cover 5 and elements 6 may be modified such that they form a surface simulating a wood fire, with or without coal in it. The gas burners and radiants may be replaced by some form of electrically powered heating unit, for example electrical radiant heater elements; alternatively the display unit may be used by itself, i.e. without any form of heating unit, for decorative purposes alone.

Clearly, a display unit embodying the present invention may have as many flicker-flame lamps as considered appropriate, there being no technical limitation or optimum amount; however it should be noted that if a unit is to have only a few such lamps, it is advantageous for one or more to have a plurlity of corresponding windows in order to maximise the effect of the lamps.

A unit embodying the present invention may also include other features, not disclosed above, which would be evident to a man skilled in the art.

Claims (10)

1. A display unit for simulating a solid-fuel fire, the unit comprising a housing having a surface which simulates solid fuel, at least one gas discharge lamp within the housing, the at least one lamp having electrodes shaped and arranged to provide, in use, an unstable mode discharge, at least one window in the simulation surface to enable the lamp to be viewed directly from outside the housing.

2. A display unit according to Claim 1, wherein a substantially transparent section of the simulation surface forms a window.

3. A display unit according to Claim 1 or Claim 2 wherein an aperture in the simulation surface forms a window.

4. A display unit according to any one of the preceding claims, wherein two or more of the lamps are mounted on a common support secured to the housing.

5. A display unit according to any one of the preceding claims, wherein a lamp is secured individually to the simulation surface.

6. A display unit according to any one of the preceding claims, having a light source to simulate a background glow.

7. A display unit according to Claim 6, having movable shutter means to vary the simulated background glow of the light source.

8. A display unit substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.

9. A heater incorporating a display unit according to any one of Claims 1 to 8.

10. A heater according to Claim 9, fuelled by gas or electricity.