EP2097677A2

EP2097677A2 - Simulated electric fire having a light source generating multiple colours

Info

Publication number: EP2097677A2
Application number: EP07822846A
Authority: EP
Inventors: Martin Betz; Aubrey O'coimin
Original assignee: Basic Holdings
Current assignee: Basic Holdings
Priority date: 2006-11-24
Filing date: 2007-11-23
Publication date: 2009-09-09
Also published as: GB2444074A; WO2008062061A2; WO2008062061A3; GB2444074B; GB0623465D0

Abstract

A simulated fire is described that includes a light source that generates multiple colours which are mixed in a ratio to define a coloured output which is then incident on a fire simulation means to generate on a screen an image of a fire. The multiple colours are desirably output from one or more multi-coloured LEDs.

Description

Title

Simulated Electric Fire having a light source generating multiple colours Field of the Invention

The present invention relates to electric fires and in particular to an electric fire that includes a light source providing a plurality of colours so as to enhance the quality of the flame effect generated. In a preferred arrangement the light source includes one or more light emitting diodes (LEDs) of the type known a multi-coloured LEDs to provide for internal illumination.

Background

Electric fires are well known and are used to create the illusion of a real fire, typically in a domestic environment. Such fires may include a chassis that incorporates a fuel bed that simulates coals or logs or any other desired effect. A flame effect is typically provided in a vertical orientation, the flames being provided in one of a number of different fashions, some of which are described in our earlier applications WO02068875. Such arrangements discuss the use of tungsten filament light bulbs for providing the internal illumination necessary to provide lighting for both the flame and/or fuel beds.

The use of such filament light bulbs is limited in that their colour output is not controllable. Effectively the colour generated is dictated by the nature of the filament bulb used, is a single colour and it is not subsequently alterable. While providing a source of illumination, when used to generate flame effects in simulated flame effect fires it is difficult to match the generated flame colour to that expected from a burning fire. Furthermore their power consumption is quite high which is not environmentally friendly.. Yet a further disadvantage is their lifetime, in that the lifetime of filament bulbs is quite short. This can present a specific problem when they are used in the internal portions of fires and would have to be changeable by the customer as opposed to by a trained technician. In these circumstances is behoves the manufacturer of the fire to provide an opening in the chassis of such fires to enable a user to easily change the bulbs, as required. This is an additional assembly requirement in the fabrication of such fires.

There are therefore a number of problems associated with such arrangements.

Summary

These and other problems are addressed by an electric fire in accordance with the teaching of the present invention that includes at least one light emitting diode as a light source and generates a multi-coloured output, which may then be directed onto flame generating means for creation of flame effects on a screen. The LED may also be useable for illumination of a fuel bed.

By providing a multi-coloured output it is possible to closely correlate the colour of the displayed flame with the expected colours from a real fire. Such an output may be provided by incorporating one or more LEDs of the type known as multi-coloured LEDs whose output from a single LED is a combination of two or more colours.

Accordingly the invention provides a fire in accordance with claim 1. Advantageous embodiments are detailed in the dependent claims thereto. The invention also provides a rotatable drum according to claim 51 , with advantageous embodiments provided in the dependent claims thereto.

These and other features will be understood with reference to following drawings.

Brief Description Of The Drawings The present invention will now be described with reference to the accompanying drawings in which: Figure 1 is a section through an electric fire incorporating LEDs in accordance with the teaching of the present invention.

Figure 2 is a section through a second embodiment of an electric fire in accordance with the teaching of the invention showing an alternative mounting arrangement for the LED.

Figure 2a is a section through a fire in accordance with a further embodiment which uses a single LED to provide illumination for both the fuel bed and the flame effect means, and which also provides for a mounting of the heating element in an upper region of the fire. Figure 2b is a section through a further embodiment which shows the use of a single LED to provide for illumination within the fire.

Figure 3 is a section through another embodiment of an electric fire incorporating an LED in accordance with the teaching of the invention.

Figure 4 is a perspective view from above of a mounting arrangement including optics for use with an LED within the context of fires in accordance with the teaching of the invention.

Figure 5 is a perspective view of an alternative optics arrangement to that of Figure 4.

Figure 6 is a rear view of internal portions of an electric fire in accordance with the teaching of the invention.

Figure 7 shows an embodiment of a rotatable drum in accordance with the teaching of the invention which is useable to generate flame effects on a screen.

Figure 8 is a schematic showing how a fire using a drum according to Figure 7 could be arranged to generate the flame effects.

Detailed Description Of The Drawings

Preferred but exemplary embodiments of the invention will now be described with reference to Figures 1 to 8. Figures 1 and 2 show in section view an example of an electric fire incorporating one or more light sources according to the teaching of the invention. The fire is configured to simulate the effect of a burning real fire and includes a chassis 105 within which a fuel bed 110 is mounted horizontally in a mid region of the chassis towards the front 115 of the fire. The fuel bed 110 is provided on a platform 120 and may comprise artificial coal or logs as desired. Other modifications to the arrangement of artificial fuel beds are well known and will not discussed herein.

In this example of a chassis, the fuel bed may be considered as being located in a main upper compartment 130 of the fire and is separated from a main lower compartment 140 by a partition 150. The lower chamber 140 typically contains any suitable means for providing a thermal output, for example a forced air convection unit 155 generally comprising an electric heating element and a fan for passing an air stream over the element. As such heating means are known in the art, no further details need be given.

As mentioned above the fuel bed 110 is located towards the front of the chassis, so as to be visible from the front of the fire. The main upper compartment may be sealed at this front portion by a transparent panel 160 which in some arrangements may be tinted. Other modifications to the panel may include an at least partial mirroring of the front surface of the panel 160 such that when the flame effect is not being generated that a user views a reflection of themselves in the panel. This panel may be made of glass (e.g. so- called smoked glass) or plastics, e.g. acrylic or perspex. Of course it will be appreciated that the provision of a panel at the front of the fire is not essential.

The platform 120 on which the fuel bed is located is preferably a diffusing screen, e.g. a sheet of frosted or translucent glass. Other arrangements may include a simple bracket mounting arrangement, i.e. the fuel bed does not have to be fully supported across its entire lower surface. Beneath this platform a pivotally mounted light fan or flicker wheel 165 may be provided. This flicker wheel may be driven by a motor. A first light source 170 may be provided and is secured to the chassis, either directly or by providing the light source in a holder and having the holder secured to the chassis. The light source may be a conventional filament bulb or more preferably is a light emitting diode (LED). The fan 165 is a generally circular element with reflective vanes driven by thermal currents rising from the light source when it is switched on. The rotation of the flicker wheel causes the simulated fuel bed to also flicker thereby resembling glowing coals. It will be understood that the use of filament bulbs results in a generation of such thermal currents. However, in the preferred embodiment where the first light source is desirably of the type provided by one or more light emitting diodes (LEDs), and is orientated to shine light upwardly towards the fuel bed located thereabove, it may be necessary to provide a powered rotation of the flicker wheel- LEDs not generating a large amount of heat. Of course the use of such a flicker wheel will be understood as being an optional accessory to a fire, and that it may be dispensed with completely or replaced with alternative ways of colouring the fuel bed 110. The securing of the first light source to the chassis is desirably to the platform 150 that separates the lower compartment 140 from the upper compartment 130.

A screen 180 extends upwardly from the simulated fuel bed 110 towards the upper part of the chassis 105. Screen 180 may be one or more panels having a partially reflecting surface and a diffusing surface. Suitably, screen 180 is made from a sheet of transparent material, such as glass, acrylic or perspex, having a lightly silvered surface on its front side (i.e. that side facing the front panel 160) and having, on its rear side, a surface which is configured to diffuse the light passing through. This may be provided by having closely spaced lines scored or otherwise produced on the surface. For example, the lines may be photographically produced on the rear surface. The lines may be horizontal, or inclined, or cross-hatched, in order to provide a suitable diffusing effect. Any other technique which provides for the fabrication of a diffusing surface on the rear surface of the screen will be equally useful within the context of the invention in that it is not intended to limit the provision of the diffusing surface to any one technique.

The fire also includes means 185 for simulating a flame effect. Such means, in the exemplary arrangements of Figures 1 and 2 is located behind the screen 180 and comprises a moveable material in the form of a fabric 186. While any moveable material may suffice, the provision of a fabric separated into one or more fabric ribbons, which hang in a substantially vertical and spaced relationship at the rear of the chassis is a preferred arrangement. The fabric is arranged such that it will tend to ripple or undulate in a current of air provided by a small tangential fan unit 188 which is situated either above or as shown in Figures 1 and 2, below the lower ends of the ribbons and which extends across most of the lower portion of an otherwise substantially airtight chamber 130a. Further information on the type construction of such ribbons that may be used is found in our earlier British Patent, GB2230335.

Although not shown in this sectional view, a rear surface 187 of the chassis 105 may be provided with a patterned effect so as to resemble one or more flames. Such patterning may be achieved by providing regions of varying reflectivity and patterning the higher reflectivity regions to resemble flames. The patterned effect can be provided integrally on the rear surface or alternatively on a preformed panel that is then located on the rear surface. The patterned effect will be located behind the ribbons. When illuminated, the regions of high reflectivity will create more dominant visual effects on the screen than the regions of low reflectivity.

The rear surface 187 of the chassis is also illuminated using a light source 190. This light source, which may be the same or a different light source to that used to illuminate the fuel bed is of the type provided by one or more light emitting diodes (LEDs), and preferably a multi-coloured LED. A multi-coloured LED is a specific type of LED that generates two or more colours as an output from the LED. On application of a specific control signal, the ratio of the two or more colours generated relative to the other colours can be varied such that the resultant colour may be tailored for specific requirements. In this way the LED colour output may be matched to the desired colour for the flame effect that is generated.

As the LED(s) provide a light source that is a directional light source it is important to mount the LED in a fashion that correctly orientates the LED(s) relative to the rear surface, so as to achieve the correct height of illumination. It will be understood that the higher the illumination up the rear surface, the higher that the viewed flames will appear to an observer to the front of the fire. Desirably the height of the flames is such as to occupy around 50% of the screen on which they are visible, however heights may range from 5% upto about 80% of the area of the screen. While a fixed mounting may be suitable for certain applications it is also possible, as shown the in the arrangement of Figure 1 , to provide the LED(s) on a mounting that allows for subsequent modification of the angular orientation of the LED relative to the rear surface. Such modification may be achieved by providing the LED on a tiltable mount 191 , whose angle of tilt 192 may be varied as required.

Figure 2 shows a second way in which the relative height of the viewed flames may be changed. In this arrangement, the LED(s) are provided on a moveable frame 200 that can move upwardly and downwardly in a vertical axis. One example of how this may be achieved is by providing a spindle arrangement 205 with upper 205a and lower 205b members. The spindle arrangement has mounted thereon the moveable frame 200 and by winding a thread 210 on the spindles in a desired direction it is possible to cause the frame to move upwardly and downwardly within the chassis relative to the rear surface 187. Both these arrangements for modifying the height subsequent to installation may be considered advantageous but not essential within the context of the teaching of the invention, what is important is that correct orientation of the light source is achieved, be that permanent or variable in its nature.

Heretofore the examples of the fire described have incorporated first and second light sources, being used to illuminate the fuel bed and flame effect means respectively. Of course if a single light source is provided within the chassis in an orientation that may illuminate both the fuel bed and the flame effect means simultaneously, it may not be necessary to include two light sources. Such examples are shown in Figures 2a and 2b, where the same reference numerals are used for the same integers. In both these latter two arrangements a single light source 190 is orientated to provide illumination for both the fuel bed and the flame effect means. Figure 2b shows that although a single source 190 could be used to illuminate the fuel bed and flame effect means simultaneously, that this light could be supplemented with an additional light source 190a directing light into the fuel bed. In this way the fuel bed will appear to have an additional brightness at the rear of the bed, closest to the screen 180, and arising from the lighting effects of the two sources 190, 190a. In this way this area of the fuel bed will resemble the real appearance of a burning fuel bed more closely. In any case irrespective of the number of light sources used to provide illumination, when the light source(s) are switched on, the simulated fuel bed 110 is illuminated and the partially reflective surface of screen 180 provides an image of the fuel bed. The fan 188 creates undulating movement of the ribbons 186 and light from the light source is therefore reflected randomly onto the back of screen 180 so as to simulate flickering flames. This flickering image is perceived between the actual simulated fuel bed 110 and its image in the screen 180 so that the flames appear to be emanating from somewhere in the middle of an extended fuel bed. The colour of this perceived image is a function of the light output from the LEDs that are used to illuminate the flame effect means, the actual colour of the material used and the colouring of any reflective surfaces that are used within the chassis of the fire. The image is not created by a direct illumination of the screen by the light sources but rather arises from an interaction between the light output from the light sources and the flame generating means which results in reflection of the light onto the screen to form a suitable pattern corresponding with that of a flame pattern.

Where the fire is discussed as having one or more light sources, it will be understood that this is not intended to mean only a single light source. What is intended is that each light source is at a specific location within the chassis but could comprise a plurality of individual lighting sources within an array at that location.

The physical location of the heating element within the chassis is not important within the context of the invention, as it may be found equally convenient to mount the heating element in an upper region of the fire. Such an example is shown in Figure 2A, where the heating element 155 is located in an upper region of the fire and is arranged to direct heat downwardly over the front of the screen 115.

It will be understood that the mounting arrangements described in Figures 1 and 2 allow for the orientation of illumination provided by the light source 190 relative to the rear surface to be changed. This can be provided in a motorised fashion such that a user can select a desired flame height and the relative orientation of the light source to the rear surface will be changed appropriately. It can also be combined with a programmable element that will enable a level of automation in this changed orientation. For example the fire may be provided with a number of different flame arrangements such as an early stage fire, a roaring fire and then a dying fire. In each of these three examples the height of the flame will be changeable, the highest flame being associated with the roaring fire. Using the teaching of the present invention, the viewing user of the fire can be presented with an aesthetic that resembles the traditional life of the fire by suitably programming an orientation of the light source relative to the fire. This control could also be used in conjunction with changes in the speed of movement of the fabric or the illumination output of the light sources to more closely resemble the activity of a real fire. While the changing of the orientation of the light source relative to the rear surface may be effected by moving the mount on which the LED is mounted it will be understood that equally the surface orientation could be moved, what is achievable using the teaching of the invention in this specific embodiment is a relative change in the orientation of the surface on which the light from the LED is reflected from and the LED itself.

In the arrangements of Figures 2a and 2b, the orientation of the LED relative to the flame generating means is determined at the time of manufacture and is not subsequently moveable. Thus it will be appreciated that a movement of the LED within the chassis is not an essential feature of the invention.

Figure 3 shows another embodiment of a fire 300 in accordance with the teaching of the invention which also uses one or more LED's for internal illumination of the fire but does not include moveable material such as a fabric to create the flame effect. In this embodiment the same reference numerals are used for components already described with reference to Figures 1 and 2. The fire includes a chassis 301 , that houses a fuel bed 110 that is located in front portion of a main upper compartment 330. The fuel bed 110 is positioned in front of a light diffusing and reflecting screen 180, which reflects an image of the fuel bed. A light source in the form of one or more LEDs 305 is positioned in a lower main compartment 303 and directly illuminates strips of foil 306 on a rotor 307, whereby moving beams of light (B, C) are reflected from a rear reflector 310 onto an inner surface 180b of the screen 180. The foil and rotor collectively are referred to as a rotisserie. When the rotissehe rotates, moving beams of light appear like flickers moving upwardly on the screen 180. An auxiliary reflector 315 reflects moving beams along another path (D) to be viewed by a viewer nearer to the appliance. The appliance houses a fan heater 155 located in the base of the chassis and orientated to blow heated air outwardly from the front of the fire. The reflector 310 may be fixed or have a variable angle of inclination, and this angle of inclination may be moveable during use of the fire. Similarly to what was described with reference to Figures 1 and 2, a translucent panel 160 may be provided in front of the fuel bed. This panel may be tinted, partially reflective or masked. Another arrangement for generating a flame effect could be the provision of a rotatable drum that has regions of different reflectivity provided on its surface. This could be generated by having one or more apertures provided in a surface or indeed patterning the surface with regions of different reflectivity. As the drum rotates the surface presented to the illumination emitting from the light source and the resultant reflection from that surface varies depending on the nature of the surface. It is therefore possible to generate a different pattern on the screen depending on the rotation of the drum.

In a similar fashion to the mounting of the LEDs in Figures 1 and 2, the LED 305 may also be provided with mounting means that that allow its orientation to be modified. In the schematic of Figure 3 such mounting means is shown in the form of a tiltable mount 320, whose angle of orientation allows a changing of the relative angle between the end plane of the LED and the rotisserie. By changing this angle it is possible to alter the angle of illumination of the light emitted from the LED onto the rotisserie. This can then serve to change the apparent height of the viewed flames. The height could also be changed by providing a movement of the rear surface 310. Of course it will be understood that such relative movement is not a requirement of a fire in accordance with the teachings of the invention. The invention has heretofore been described with reference to LEDs mounted within an electric fire. There are many types of LEDs available from those having a monocolour output of a first intensity to higher intensity outputs to those having an output made up of a plurality of colours. Where a mono- coloured LED is used, the colour does not have to be a white light as any desired colour could be chosen. Within the context of the present invention it is desirable that at least one multi-coloured LED be used, such that the light provided onto the flame effect means is made up of a plurality of colours. In this way the use of a multi-coloured LED is preferable as that inherently generates that multi-coloured effect. However if two or more mono-coloured LEDs of different colours are used, lens arrangements could be used to combine these colours in a desired mix, prior to their output impinging on the flame effect means.. While the make up or fabrication of a LED is well known to the person skilled in the art, for the sake of understanding a brief description of such fabrication will now be described.

A basic LED consists of a semiconductor diode chip mounted in the reflector cup of a lead frame that is connected to electrical (wire bond) wires, and then encased in a solid epoxy arrangement which determines the shape of the beam output. In this way the epoxy casing can be considered a beam shaper or, as sometimes called, a lens. LEDs emit light when energy levels change in the semiconductor diode, and the colour is dependent on the nature of semiconductor and/or the colouring used in the fabrication of the epoxy beam shaper. The output pattern of the LED is defined by the beam shaper.. In preferred embodiments of the invention such conventional LED arrangements are modified such that individual LEDs may be mounted within a lens system that provides a second beam shaper above the first epoxy beam shaper, in effect a compound lens effect. Such an arrangement is shown in Figures 4 and 5. Within the present invention the terms beam shaper and lens are used interchangeably, as both function to define the shape of the output beam. As the output shape of the beam is controllable it is possible to ensure that it is directed correctly within the fire and therefore easier to mix light output from two sources to achieve a desired illumination.

In Figure 4, a lens system 400 is shown that is optimally configured for use with the LEDs that are used to illuminate the rear surfaces of the chassis. Each LED is mounted on a lead frame 405 that provides electrical connection 410 to mounted LED. One or more circuit tracks 415 provided on a printed circuit board allow the provision of electrical power and also control signals to be provided to the LED. Such control signals can be used to determine the on/off characteristics, the luminosity and other optical characteristics of the LED. A lens holder 420 is provided to house a second lens 425, which is desirably configured to co-operate with the output of the first lens (not shown) to change the overall output of each LED. The combined lens holder/second lens are then mounted relative to the LED/first lens combination, desirably by fixing the lens holder to the lead frame to which the LED is fixed. The use of such a compound lens arrangement is advantageous in that the light output from the LED can be adjusted to provide a more distributed pattern which when viewed from the front of the fire is a more realistic effect than what would be achieved without the second lens. In preferred implementations the output pattern of the LED is changed from the substantially circular pattern that is provided by the first lens to a rectangular pattern as an output from the second lens.

The specifics of the lens arrangement used for the second lens will depend on the specific orientation chosen for the actual LED. It will be understood that conventionally the output defined by the first lens is a substantially circular output. In the configuration of Figure 4, this second lens is provided with a plurality of ridges 426 on its upper surface that serve to modify the circular output pattern of the first lens to a substantially rectangular pattern. While this pattern could be arranged in a landscape or portrait configuration, it is desirably provided in a portrait mode where the height of the illumination is emphasised as opposed to its width when used with the moveable fabric and in a landscape mode where the wifth of the illumination is emphasised as opposed to its height when used with the rotatable drum. The ability to select the orientation of the light impinging on the flame generating means is a distinct advantage arising out of the teaching of the invention. The change in illumination pattern is possible as the shape of a rectangle can be used to broaden or heighten the output pattern, the two patterns being 90 degrees out of phase with another. Such a change is achievable by moving the relative positioning of the lines 425 on the second lens surface relative to the LED mounted therebelow. By using two or more LEDs arranged side by side it is possible to generate a distributed light source across the back surface of the chassis which provides the desired degree of illumination for the desired flame pattern.

Where mono-coloured LEDs are used, the colour output of such mono- colour LEDs can be modified by suitably tinting the second lens to provide an integrated filter or by using a secondary filter that is mounted above the lens arrangement such that light emitted by the LED is filtered prior to incidence on the flame generating means. The former arrangement is preferred where there is a desired predetermined colour output and there is a desire to reduce the number of separate components that need to be mounted within the chassis whereas the latter configuration provides a level of flexibility in that the non- integrated filter can be changed subsequent to installation. Of course the two arrangements could be used together to provide a further degree of colour selection- achieved by mixing the filters as desired for the output required. In this way a multi-coloured output may be provided as incident light onto the reflective surfaces that make up the flame generating means.

While it is possible to provide mono-colour LEDs and to use filters with these LEDs to provide a change in the achievable colour output, the teaching of the present invention advantageously employs multi-coloured LEDs, where the output from a single LED is a combination of colours. The use of such multicoloured LEDs is advantageous in that the requirement for physical filters is obviated, as the colour sequence output can be modified by applying a suitable electrical control sequence or signal to the LED. Also such multi-coloured LEDs provide a higher number of distinct colour variations which are controllable electronically than are available using physical filters.

One of the issues with use of multi-coloured LEDs is however that their output is a mix of the component colours. Therefore, if such an output is incident on a physical baffle it can cause diffraction effects which may result in a break up of the light output to its constituent colours. The invention addresses such issues by employing a specific lens configuration to minimize such diffraction effects. Figure 5 shows an example of such a compound lens configuration 500 that may be used in conjunction with multi-coloured LEDs. Similarly to that described with reference to Figure 4, this lens configuration includes a second lens 505 mounted in a lens holder 510 relative to the LED provided in a lead frame 515 therebelow. The second lens is provided as a microlens array, the use of which may minimise any dispersion or diffraction effects that will occur if the light emitted by individual LED's is incident on a surface within the chassis of the fire. When activated, the light from the LED is directed by the orientation of the lenses to a desired pattern that can be used to ensure that diffractive effects are minimised within the illumination area served by the LED array. Electrical connections 520 can be provided to each of the lens systems to provide power and control to the individual LEDs. The lens holder used to maintain the orientation of the second lens relative to the LED is usefully a separate structure within which the second lens may be seated. However where required, the second lens could be provided with integral legs that may be used to locate the second lens over the LED below.

By using multi-coloured LEDS such as those provided by (RGB) Red, Green and Blue, or indeed dual coloured red and green, high brightness LEDs that are pulse width modulated (PWM) or controlled in some other suitable fashion it is possible to vary the intensity of each colour output from the LED. It is preferable that where a multi-coloured LED is used that at least red and green colour outputs are available from the LED as these colours represent primary constituents of any generated flame. The PWM is desirably implemented using a software routine carried out by a standard microcontroller. This routine allows effectively any colour to be generated with rapid changing strobe effects, fast and slow colour fades as well as static colours producing in effect over 16 millions colours.

It will be understood that the use of LEDs provides a number of advantages over the prior art filament arrangements such as:

1 ) Longer life: LEDs are rated up to 100,000 hours life (over 22 years at 12 hours per day)

2) Lower power consumption (up to 80% less) than conventional filament bulbs . For example, typical filament bulb power consumption in an electrical fire is about 100 watts, LED total power consumption in comparison is about 21 watts.

3) Durable (LED modules will not break like standard glass bulbs)

4) Increased reliability which has the potential to minimise cost associated with servicing and support, and also reduces the need to provide easy access for bulb replacement.

5) Less waste heat produced

6) High efficiency.

Where multi-coloured LEDs are used in the context of the fire of Figures 1 or 2 it is preferred that one or more multi-coloured LEDs be used for illuminating the flame effect means whereas mono-coloured LEDs may be used for illuminating the fuel bed. In the context of the fire of Figure 3 where the LED providing the rear illumination also serves to illuminate the fuel bed, it is preferable that the multi-coloured LED be used in embodiments requiring a plurality of colour sequences. In all arrangements employing the multi-coloured LEDs it is desirable that a processor arrangement be included within the chassis to provide suitable drive signals for the LEDs. The choice of colour can then be varied depending on the specific visual effect desired. Where used in combination with the changing orientation of illumination such effects can readily resemble the different changes in the life of a fire. Suitably the processor can be used to pre- programme these events such that they are activated concurrently. While the nature of the program may be preset by the manufacturer, further modifications may employ a remote control system whereby the user can select a desired fire type and by activating a suitable control sequence can cause that effect to be simulated. The implementation of such processor controls of LEDs and its interface with a remote control unit will be apparent to the person skilled in the art and requires no discussion here.

As discussed heretofore, a fire in accordance with the teaching of the invention employs one or more LEDs to provide internal illumination to simulate fire effects. In the embodiments described with reference to Figures 1 to 3, the fire is of a type that uses reflection of light from a light source within the fire on a flame generating means such as a moveable material or a rotatable drum to provide an effect where flames generated appear to be emanating from within a mid-portion of the fuel bed. Figures 6 to 8 show modifications to such an arrangement.

In the example of Figure 6, a plurality of LED's 605 are provided so as to provide for internal illumination within the chassis 610 of the fire. Such an arrangement is desirable where the LEDs used are of a low output wattage or indeed where a distributed pattern is desired. The individual LEDs may be provided so as to form an array 615 which is located in a lower portion of the fire 100. In the arrangement of Figure 6, the array is formed by mounting each of the LEDs on a frame 620 prior to installing the LED array 615 into the chassis 610 of the fire. The prior mounting of the LEDs on their dedicated mounting frame ensures that accurate location of the LEDs within the fire can be achieved as the location of the frame can be accurately enabled using one or more alignment features. This also addresses the problem of locating intricate items within the reduced space available in the internal portions of the chassis, which would occur if each of the LEDs used were individually mounted within the chassis. It is much easier to mount the LEDs onto their respective location on the frame when the frame and LEDs are outside the chassis than when they are inside. This can increase the speed of assembly of such fires immeasurably.

The use of such a frame is also advantageous in that it may be used to provide a heat sink for the individual LEDs such that heat generated by the LED can be easily taken away from the heat source, thereby reducing the possibility of overheating. Such a provision can be provided using a metal material to form the frame. Desirably the LEDs are mountable on a metal core printed circuit board which may then be attached to a heat sink by way of conduction. The heat sink may then suitably dissipate the heat generated by convection.

The frame may also include one or more electrical connections 625, 630 that can be used to provide power to the individual LEDs. Such incorporation of the necessary electrical connections that are required for the operation of each of the LEDs is advantageous where a number of LEDs are provided, as the electrical connections can be tested prior to installing the LEDs within the fire, thereby reducing the time required to fabricate a complete fire. Furthermore the electrical connections can be fabricated during construction of the frame- such as using printed circuit board technology to ensure that each electrical connection is provided as required.

Each of the LEDs can be individually or collectively controlled using a electronic controller 635 such that the timing sequence can be altered as desired. This can provide varying visual effects which provide improved aesthetics to the viewing used.

In the orientation shown in Figure 6, the mounted LED array is provided below a fuel bed 650, in a lower portion 640 of the fire, and shine upwardly to illuminate a lower surface of that fuel bed. While the individual LEDs may be provided by standard ultrabrite one colour LEDs, in a preferred embodiment, the LEDs include one or more multicoloured LEDs such that by applying an appropriate electrical signal the colour output of the LED can be controlled. This has particular application in defining the viewed colour of the fire, where the user may wish to simulate an actual burning fire. In such arrangements the colour and intensity of the flames will change during the burn sequence and this can be simulated using a combination of one or more multi-coloured LEDs with suitable controllers such as the controller 635 of Figure 1. Where the use of such multi-coloured LEDs is not practical different colours can be used by providing a plurality of single colour LEDs and either positioning them individually behind different filters or applying different coloured dyes, such as an amber/orange dye to the clear optics in the manufacturing process gives an almost colour match to existing flame effect using incandescent light bulbs. By selectively activating individual ones of these coloured LEDs it is also possible to change the overall colour viewed.

In the arrangement of Figure 6, the schematic illustrates how the LEDs are used for illumination of the fuel bed and no flame effect is provided. The colour sequence used to illuminate the fuel bed may be provided by the use of multicoloured LEDs as just discussed or by using mono-coloured LEDs with a rotatable filter arrangement 645 which is segmented with each segment providing a desired filter. By orientating the segmented disc relative to the light source below, the light colour incident on the fuel bed may be suitably changed. While shown in the context of the fuel bed illumination it will be understood that equally such an array could be used for illumination of the flame effect means. Figures 7 and 8 show an alternative arrangement for generation of fire effects within an electric fire. In this embodiment, a rotatable drum 700 which is rotatable about an axis 710 in a similar fashion to the rotisserie arrangement is provided with integrally formed or mounted LEDs 715 on its surface 720. By patterning the surface 720 with the LEDs in a suitable fashion as the drum rotates the light that is emitted in a specific direction will change. As shown in Figure 8, such light 810 can then be directed through a mask 800- which is suitably provided with a patterned surface of varying transmissivity so as to generate on the screen 180 a suitable flame pattern. The provision of the mask 800 with a flame pattern provided thereon provides for the shape of the ultimate pattern on the screen whereas the rotation of the drum 700 changes the light that is passed through that mask so as to vary the ultimate image. The LEDs chosen on that drum could be a mixture of mono-coloured LEDs of different colours, of multi-coloured LEDs or just a combination of LEDs. Such an arrangement differs from that heretofore in that the flame generating means and the light source are integrally formed and the flame generated on the screen does not arise out of reflection of the light against the flame generating means. In this context the flame generating means can be considered as including the mask 800 and the light is still directed onto the flame generating means to generate the flame pattern. In this arrangement the light it directed onto and through the flame generating means whereas in the previous arrangement it was directed onto and reflected off the means. As the light intensity in the arrangement of Figures 7 and 8 is not diminished arising from reflection losses it is possible to use lower intensity light sources than required in the reflection arrangements heretofore described.

What has been described herein are exemplary embodiments of a electric fire that provides for one or more LEDs used in the generation of a light pattern that is formed from multiple colours and is used for internal illumination purposes within the chassis of a fire. The use of such LEDs provides for improved performance and characteristics of the fire, specifically in that the provision of flames with different colours may be generated, the colour of the flame effect generated may be varied and the flame effect may be controlled.

A simulated fire in accordance with the teaching of the invention includes a light source that generates multiple colours which are mixed in a ratio to define a coloured output which cooperates with a fire simulation means to generate on a screen an image of a fire. The multiple colours are desirably output from one or more multi-coloured LEDs.

The use of a light source that generates a light output which is made up of multiple colours allows for the creation of a flame effect that more closely resembles that of real flames, in effect a better simulation of the flame effect than heretofore possible using conventional light sources. The flame effect generated could be maintained in the same colour or could be varied by suitable control of the electronic controller that is used to control the output of the light sources.

While preferred embodiments have been described with reference to the figures modifications can be made without departing from the scope of the invention which is to be limited solely by the claims. Where integers or components are described with reference to one figure it will be understood that they can be interchanged with those of another Figure without departing from the context of the invention.

The words comprises/comprising when used in this specification are to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers , steps, components or groups thereof.

Claims

1. An electric fire having a chassis including a light source and a simulated fire means including flame effect means which interact with the light source to generate simulated flame effects on a screen provided within the chassis and simulated fuel means provided to simulate a bed of combusting fuel and wherein the light source includes at least one light emitting diode and generates a multi-coloured output, and wherein the screen is positioned between said flame effect means and said simulated fuel means, said screen being capable of diffusely transmitting light reflected by said flame effect means and the screen is also capable of reflecting light from said simulated fuel means so that the simulated flames appear to emanate between the simulated fuel means and an image of the simulated fuel means reflected in said screen means

2. The fire as claimed in claim 1 wherein the at least one LED is a multicoloured light emitting diode (LED)

3. The fire of claim 2 wherein the at least one multi-coloured LED is controllable using an electric controller such that application of a suitable control signal from the controller defines the colour output of the LED.

4. The fire of any preceding claim wherein said flame effect means comprises moveable material supported so as to be capable of movement, and means for causing said movement.

5. The fire of claim 4 wherein said material is a fabric in the form of a plurality of vertically arranged ribbons locatable in a rear portion of the chassis behind the screen means, the screen means separating the ribbons from the fuel bed.

6. The fire of claim 4 or 5 wherein the means for causing movement is an air blower configured to direct air onto the moveable material to impart movement.

7. The fire of claim 6 wherein the flame effect means includes a rotatable drum.

8. The fire of claim 7 wherein the rotatable drum has regions of different reflectivity provided on its surface.

9. The fire of claim 8 wherein the regions of different reflectivity are formed by having apertures provided in the surface of the drum.

10. The fire of claim 9 wherein the rotatable drum has reflective strips having either the same, or different colours, provided thereon.

11.The fire of claim 10 wherein the reflective strips are circumferentially arranged about the rotatable drum, the drum being located in a lower region of the chassis below the screen.

12. The fire of claim 11 further including a reflector, the reflector being arranged relative to the rotatable drum and the screen to reflect light originating from the drum onto and through the screen means.

13. The fire of claim 12 wherein the reflector is provided on a rear surface of the chassis behind the screen.

14. The fire of claim 12 or 13 wherein the reflector is arranged such that its orientation relative to the light source is changeable.

15. The fire according to any preceding claim wherein said screen is a translucent or transparent panel or panels having a reflective surface and a diffusing surface.

16. The fire according to any preceding claim in which said screen is a single panel having a lightly reflective front surface and a rear surface configured to provide a diffusing surface.

17. The fire according to any one of the preceding claims having a transparent front panel through which the simulated fire effect means and the screen are visible.

18. The fire according to claim 17 wherein said transparent front panel is tinted so that the simulated fire effect means and the screen are substantially obscured when the source of light is extinguished.

19. The fire according to claim 17 or 18 wherein the front panel is both transparent and reflective whereby multiple front-to-back images of the simulated fuel means are provided and the simulated flames appear to emanate from different regions in an extended bed of fuel.

20. The fire as claimed in any one of claims 17 to 19 wherein the front screen includes a front surface that is at least partially reflective such that when the light source is not activated a user views an image of themselves in the front screen.

21.The fire as claimed in any preceding claim wherein the relative orientation between at least one multi-coloured LED and the flame effect means is changeable, a changing of the orientation effecting a subsequent altering of the height of the viewed flame.

22. The fire as claimed in claim 21 wherein the at least one multi-coloured

LED is mountable within the chassis on a moveable mount, a movement of the mount providing for a changing in the orientation of the LED relative to the screen means.

23. The fire as claimed in claim 22 wherein the movement provides for a change in the angular orientation of the at least one multi-coloured LED relative to the screen means.

24. The fire as claimed in claim 22 or 23 wherein the movement provides for a movement of the at least one LED along a vertical path within the chassis of the fire.

25. The fire as claimed in any one of claims 22 to 24 wherein the movement of the mount is controllable using the controller or using a manual control

26. The fire as claimed in any preceding claim wherein the light source is useable to illuminate a fuel bed provided within the fire.

27. The fire as claimed in any preceding claim including at least one mono- coloured LED, the at least one mono-coloured LED being useable to illuminate a fuel bed provided within the fire.

28. The fire as claimed in claim 27 including at least one multi-coloured LED useable to illuminate the screen.

29. The fire as claimed in claim 28 wherein the at least one multi-coloured

LED is used to illuminate the screen and is mountable in a rear portion of the chassis, the at least one mono-coloured LED being used to illuminate the fuel bed and being mountable in a front portion of the chassis below the fuel bed.

30. The fire as claimed in any preceding claim including a plurality of multi- coloured LEDs , the LEDs being arranged within the chassis so as to provide a distributed source of illumination for the simulated fire effect means.

31.The fire as claimed in claim 30 wherein each of the LEDs can be individually or collectively controlled using a electronic controller such that the timing sequence for individual LEDs can be altered as desired

32. The fire as claimed in any preceding claim wherein the at least one LED comprises a semiconductor diode provided within a first beam shaper.

33. The fire as claimed in claim 32 wherein the semiconductor diode is LED is mounted on a lead frame.

34. The fire as claimed in claim 32 further including a second beam shaper, the second beam shaper being mountable above the first beam shaper.

35. The fire as claimed in claim 34 wherein the second beam shaper is provided in a holder that is mountable on the lead frame.

36. The fire as claimed in claim 32 wherein the second beam shaper includes a microlens array.

37. The fire as claimed in any preceding claim including a plurality of light emitting diodes (LEDs) for internal illumination of the fire so as to achieve lighting of one or more of a flame effect or a fuel bed portion of the fire, the plurality of LED's being provided so as to form an array, each of the LEDs being mountable on a frame prior to installing the LEDs into the chassis of the fire.

38. The fire of claim 37 wherein the chassis includes one or more one or more alignment features which cooperate with the frame to achieve accurate location of the LED array within chassis.

39. The fire as claimed in claim 37 or 38 wherein the frame provides a heat sink for the individual LEDs such that heat generated by the LED can be easily taken away from the heat source.

40. The fire as claimed in claim 39 wherein the frame is fabricated from a metal.

41.The fire as claimed in claim 39 wherein the frame includes one or more electrical connections that can be used to provide power to the individual

LEDs.

42. The fire as claimed in claim 41 wherein the frame is provided as a metal core printed circuit board.

43. The fire as claimed in any preceding claim including a plurality of LEDs and wherein each of the LEDs can be individually or collectively controlled using the controller such that the timing sequence for individual LEDs can be altered as desired.

44. The fire as claimed in claim 43 wherein intensity output of individual

LEDs is controllable.

45. The fire as claimed in any preceding claim including a plurality of mono- colour output LEDs, each of the outputs from the individual LEDs being mixed to define a multi-coloured output prior to incidence of the light onto the simulated fire means.

46. The fire of any preceding claim wherein the light from the light source is reflected off the simulated flame means to generate a flame effect on the screen.

47. The fire of any one of claims 1 to 46 wherein the light from the light source is directed through the simulated flame means to generate a flame effect on the screen.

48. The fire of claim 47 wherein the light source is integrally formed on a rotatable drum, a rotation of the drum effecting a change in the light that is directed through the simulated flame means.

49. The fire of claim 47 wherein the simulated flame means includes a mask, providing a flame pattern, a corresponding flame pattern being generated on the screen through transmission of light from the light source through the mask.

50. The fire of any preceding claim further including a remote control, the remote control being actuatable on the controller and allowing a user to vary the illumination provided by the light source.

51.A rotatable drum for use in generation of simulated fire effects within an electric fire, the drum including a plurality of individually controllable light sources circumferentially arranged about the surface of the drum.

52. The drum of claim 51 wherein the individually controllable light sources are formed from one or more light emitting diodes.

53.An electric fire including a rotatable drum as claimed in claim 51 or 52.