WO2008092753A2

WO2008092753A2 - Flame effect generator for electric fire

Info

Publication number: WO2008092753A2
Application number: PCT/EP2008/050527
Authority: WO
Inventors: Noel O'neill
Original assignee: Basic Holdings
Priority date: 2007-01-30
Filing date: 2008-01-17
Publication date: 2008-08-07
Also published as: WO2008092753A3; GB2446165A; GB0701707D0; CN101622500B; CN101622500A; GB2446165B; EP2115361A2

Abstract

A flame effect generator is described. By providing a light source on a moveable arm and moving the arm at a sufficiently high frequency it is possible to generate flame effect patterns which are perceptible to a viewer of the fire.

Description

Title

Flame Effect Generator for Electric Fire

Field of the Invention The present invention relates to electric fires and in particular to an electric fire providing a simulated flame effect.

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. 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.

While such arrangements are useful for providing internal illumination to achieve a desired flame effect, there is a persistent requirement for improving the flame effect achievable.

Summary

These and other problems are addressed by a flame effect generator for use with an electric fire in accordance with the teaching of the invention that includes at least one light source which is mountable on a moveable arm and configured to generate a flame effect, the generator including a controller configured to provide for activation of the at least one light source in a spatially dependent manner. Typically this is related to the frequency of movement of the arm. In this way one or more flame effect patterns may be spatially painted. Such spatial painting of luminescent imagery can be configured to provide for one or more flame effect, which depending on the specifics of the light sources used can be in one or more colours. By suitably activating the light sources it is possible to create an animated effect, which is particularly effective in the creation of the flame pattern. The spatial movement of the arm can be in a plane substantially perpendicular to the intended viewer's line of vision, or alternatively could be in a rotational manner such that every 360 degrees of movement the arm returns to its original position or could be a combination of the two.

Desirably the light source includes a plurality of light emitting diodes (LEDs) which are further desirably vertically arranged on the arm. Suitable control of the individual LEDs can provide for selective activation of appropriate ones of the LEDs to achieve a desired flame effect. Individual ones of the plurality of LEDs may be provided in different colours, or indeed individual ones of the plurality may be formed from multi-coloured LEDs whose colour output is determined by application of a suitable control signal. Within the context of the invention the term LED is to be construed broadly, as it will be appreciated that the teaching of the invention may be practiced with light sources other than LEDs.

The arm may be rotatable, such that the light source provided on the arm rotates through 360°. In another arrangement, the arm is moveable in an arc. Such movement may be achieved by fixing the arm at one end and moving the arm relative to that end so as to create a pendulum effect, the arm swings from side-to-side.

Two or more arms may be provided, so as to accentuate the flame effect created.

Accordingly the invention provides a flame effect generator as detailed in claim 1. Advantageous embodiments are provided in the dependent claims.

These and other features of the invention will be better understood with reference to the drawings which follow which are provided to assist in an understanding of the teaching of the invention and not intended to limit the invention in any way except as may be deemed necessary in the light of the appended claims.

Brief Description Of The Drawings

The present invention will now be described with reference to the accompanying drawings in which:

Figure 1 is a schematic showing portions of a flame effect generator that may be used within the context of the teaching of the invention. Figure 2 is shows how operation of the flame effect generator of Figure 1 may be used in generating a flame effect.

Figure 3 shows portions of another flame effect generator that may be used within the context of the teaching of the invention.

Figure 4 shows how operation a generator of Figure 3 may be located relative to a fuel bed.

Figure 5 shows in schematic form how the generator of Figures 3 or 4 can be used to create a flame effect.

Figure 6 shows in block form components that are useful in operation of the flame generator.

Detailed Description Of The Drawings

The invention will now be described with reference to Figures 1 to 6 which will provide assistance in an understanding of the teachings of the invention. It will be understood that such assistance is not intended to limit the present invention in any way except as may be deemed necessary in the light of the appended claims.

Figures 1 and 2 show components of a flame effect generator 100, provided in accordance with the teaching of the invention. In this arrangement a plurality of arms 105 are mountable on a rotatable disc 110. The arms provide a mount for a light source 115, which in this exemplary arrangement is provided as an array 120 of individual light emitting diodes (LEDs) 125, which are vertically mounted one above the other on the array 120. Of course it is not necessary that the stack will require axial alignment along the vertical axis of the arm, as it may be advantageous to provide one or more of the plurality of LEDs that may up the array in off-axis locations or other geometric configurations.

Suitable control of the signal provided to each of the LEDs will achieve illumination of appropriate ones of the stacked array of LED, such that light will appear to originate along the length of the arm. By using a number of arms, each of which are provided with many LEDs (typically hundreds or thousands), activating the individual LEDs at appropriate times and rotating the arms at speed of about 900 rpm, it is possible to generate animated effects for the viewer. The specific features of the individual arms are not visible to the viewer and, due to the phenomenon of persistence of vision, the viewer of the effects observes the generated images of flames.

It will be appreciated that flame effects typically are visible above a fuel bed, and by mounting the flame effect generator 100 above a fuel bed 200, as shown in Figure 2, it is possible to achieve such an effect. Typically a viewer of the fire will be located to the front of the fire, and as such it will be understood that as each arm rotates through 180° that the array of LEDs that were visible to the front of the fire will now be facing towards the rear of the fire- and hence not visible from the front. If a number of arms are used and the speed of rotation is sufficient, it is possible that the viewer to the front of the fire will see the images created by the LEDs on those arms that are facing to the front and the spatial imagery created will not be degraded by the rearwardly facing LEDs on some of the arms.

However, other solutions to obviate such problems include a provision of a mirrored surface 135 at the rear of the fire such that light emitted by the array towards the rear of the fire will be reflected back towards the front. It is also possible to include a second array 130 of LEDs which are mounted behind the first array such that for half the rotation the light viewed will be that from the first array and for the next half of the rotation, the light viewed will be from the second array. Other mounting arrangements for the LEDs may include a plurality of LEDs arranged circumferentially about the arm, such that light may be generated from all directions dependent on application of a suitable control signal.

By providing the arm on a rotational disc it will be appreciated that the depth within the fire at which the light is generated will vary depending on the location of the arm within its rotation. Such variance of the location can be used to create three dimensional or animated effects for the created flame effect. By suitably applying an appropriate control signal the light emitted from the array can be caused to flicker, as would be expected from a real flame. The use of different coloured light sources- achievable by using mono-coloured LEDs of different individual colouring or by using multi-coloured LEDs- can be used to closely resemble the expected colours from the flame. In this way a realistic flame effect pattern may be generated.

By providing two or more individual arms- shown in Figure 1 as four arms

105a, 105b, 105c, 105d- it is possible to further improve the visual aesthetic effect of the generated flame pattern. Where provided, these arms are desirably arranged circumferentially about the rotatable disc, optimally being separated from one another by the same distance. Of course it is possible that certain arrangements may only require one arm.

There is also the possibility, although not shown in the Figures, to create a planar surface upstanding from and extending all around the rotatable disc and providing a plurality of individual LEDs on that surface, the rotation of the surface presenting different ones of the plurality of LEDs on the surface to the front of the fire for viewing by a user of the fire. Therefore it will be understood that the term "arm" is to be construed broadly as meaning any arrangement that supports one or more light sources and can allow the spatial movement of these light sources.

The rotatable disc 110 is desirably mounted on a chassis 205 of the fire, and as shown in Figure 2 desirably over the fuel bed such that the flames appear to originate from the fuel bed. It will be understood that electronic circuitry and motors are required for effective control of the lighting sequence and also the rotation. These specifics of these components together with any drive mechanism required for rotation of the disc will be understood by the person skilled in the art and will not be detailed here. Suffice to say that it is desirable that they be located out of view- for example below the rotatable disc or within a rear portion of the fire.

Typically, the arrangement of the flame generator and the fuel bed are enclosed within a defined chamber 220 - the provision of at least partially transparent walls 215 provided around the perimeter of the fuel bed as shown in Figure 2 serving as a good example of the type of arrangement that may be used. Of course, it is not necessary that three sides of the chamber 220 be at least partially transparent, it is preferable however that at least the front face of the chamber is sufficiently transparent to allow a viewing of the internal portions of the chamber from a front portion of the fire.

The speed of rotation of the disc is desirably at a rate that such that the viewer of the image cannot see the arms that are used to carry the individual light sources. Such rotation is typically greater than 900 rpm and may be of the order of 2500 rpm or higher. The use of such a rotation will typically achieve refresh or repetition rates of 50Hz for the person viewing the flame generator. This high speed of movement, together with appropriate spatial activation of the individual LEDs, is used to create a persistence of vision effect for the user.

While the arrangement of Figures 1 and 2 show the use of a rotational arm, the provision of a flame generator that operates using the creation of perception of vision effects can be achieved in a number of other arrangements. As shown in Figures 3 to 5 where the same references are used to indicate similar components to that described before, it is possible to provide one or more moveable arms- shown in this arrangement as two arms 300a, 300b, whose end portion 305 moves relative to its base portion 310 so as to swing back and forth in an arc 315 whose direction is substantially perpendicular to the intended recipient's line of vision. With this side-to-side motion, the arm reaches one end of the arc and then the direction reverses such that the arm moves in an opposite direction. During the travel through the arc, the individual LEDs are located at different spatial locations relative to a rest position.

The actual movement of the LEDs is related to the frequency at which the arm is travelling and so the spatial location at any one time of individual LEDs may be predicted. By selectively activating/deactivating the LEDs in a spatially dependent manner it is possible to create an image of a generated flame effect which is perceptually sustained. The location of a plurality of LEDs along the arm can be used to generate a desired colour pattern which is useful in the simulation of flame effects. Such an arrangement is useful in that it is not a deep an arrangement and so could be located behind a screen towards the rear of the fire, without requiring a very deep chassis. Further detail on the provision of flame effects behind partially reflective/diffusive screens can be found in our earlier patent GB 2 230 335, an examination of which will indicate that the fabric used in that fire could be supplemented with or substituted by the flame generator of the present invention to achieve flame patterns.

By using two or more arms whose movement relative to one another can be controlled, such as shown in Figures 3 to 5, it is possible to generate three dimensional effects, which may be useful in improving the quality of the generated flame pattern which is viewed. The arms are again desirably located above a fuel bed 200, which is received located within a chassis 405. The entire arrangement may be enclosed within a chamber defined by upstanding walls 215, at least one of which should be at least partially transparent to allow a viewer to see inside the enclosure. The selection activation and deactivation of the individual LEDs in a spatially dependent manner can be used to create a flame pattern 500.

It will be understood that what has been described herein are exemplary embodiments of a flame generator that uses movement of a light source on an arm to create images which are perceived by a viewer as flame effects. The incorporation of such a flame generator provides for multiple possible flame effect patterns to be generated depending on the colours used for the LEDs on the arm and the sequence at which they are activated/deactivated. By moving the arm, the spatial location of the LEDs mounted on the arm will change and their activation/deactivation can be controlled in a spatially dependent manner. Such activation/deactivation can be useful in creating images that are perceptually sustained within the eye of the intended viewer. The clarity and definition of the generated image will depend on a number of factors including the number of LEDs utilised, the speed of movement of the arms and the activation rate of the individual LEDs. Under suitable conditions, the LEDs create a perceptible image of a flame pattern which is visible to the user while, the underlying movement of the generator is not perceptible to the user. While the light source has been described with reference to LED's it will be understood that these are exemplary of the type of light source that could be used within the context of the teaching of the invention. Where provided however, individual ones of the plurality of LEDs may be provided in different colours, or indeed individual ones of the plurality may be formed from multi- coloured LEDs whose colour output is determined by application of a suitable control signal.

The movement of the arm may be achieved through a plurality of different means. For example the arm may be fixed to a rotatable disc as shown in Figures 1 and 2 such that one portion of the arm does not move relative to another, but the entire arm moves in a circumferential pattern defined by the rotation of the disc. Alternatively as shown in Figure 3, one end of the arm may be fixed relative to a moveable mount such that movement of the mount effects a movement of the other end of the arm. While the arrangement of Figure 3 shows the example of the formation of an arc of movement, i.e. a translational movement in one axis forming a pendulum effect, the provision of the mount in the fashion of a gyroscope or some other ball mounting arrangement may allow the movement of the arm through 360 degrees.

By activating the light sources in a sequence dependent on the location of the movement of the arm, it is possible to achieve a spatial painting of flame effects within the electric fire. It will be understood that as the arms move, that the LEDs mounted thereon move and as such their spatial position or location within the fire alters. The activation/deactivation is effected to ensure that generated images are created at desired spatial locations within the fire. The generator may include one or more sensors which are configured to sense the location of the arm relative to a first location, and to communicate this location to the controller to synchronise the operation of the light sources with the movement of the arm(s). In another arrangement the location of the arms relative to a first location may be determined using predictive algorithms which are embedded within the controller.

Figure 6 shows in schematic form useful components of the flame generator. These include a controller 600 which is configured to act upon and control the light sources 610. Movement of the arm(s) 615 is effected using drive means 620 - of the type that will be apparent to the person skilled in the art- and which may also be coupled to the controller to allow for synchronization of activation/deactivation with the movement of the arm(s).

Therefore it will be understood that the described embodiments are illustrative of the teaching of the invention which is not to be limited in any fashion except as may be deemed necessary in the light of the appended claims. 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. A flame effect generator for use with an electric fire in the generation of a simulated flame effect, the generator including: a. at least one moveable arm having at least one light source provided thereon, b. a controller for selective activation and deactivation of the at least one light source in combination with movement of the at least one arm to generate a flame effect.

2. The generator of claim 1 wherein the light source includes a plurality of light emitting diodes arranged in an array on the arm.

3. The generator of claim 2 wherein individual ones of the plurality of light emitting diodes are configured to provide different colour outputs.

4. The generator of any preceding claim wherein the arm is mountable on a rotatable disc, a rotation of the disc effecting movement of the arm.

5. The generator of claim 4 wherein the arm includes a first array of light emitting diodes orientated in a first direction and a second array of light emitting diodes orientated in a second direction.

6. The generator of claim 4 or 5 wherein two or more arms are provided on the rotatable disc, the plurality of arms being distributed about the circumference of the disc.

7. The generator of any one of claims 4 to 6 wherein the rotatable disc is mountable within the fire in a location above a fuel effect generating means.

8. The generator of any one of claim 1 to 3 wherein the at least one arm is fixed at a first end portion to a movement generator, activation of the movement generator causing a movement of a second end portion of the at least one arm relative to the first end portion.

9. The generator of claim 8 wherein the first and second end portions are distally located relative to one another.

10. The generator of claim 8 or 9 wherein the movement defines an arc.

11. The generator of claim 10 wherein the movement is substantially perpendicular to the intended viewing direction of a user.

12. The generator of claim 8 or 9 wherein the movement is in three dimensions.

13. The generator of any preceding claim wherein the controller acts on both the light sources and the arm so as to activate the light source in a spatially dependent manner consistent with the location of the arm.

14. The generator of any preceding claim wherein the activation of the light source provides for a spatial painting of one or more flame effects.

15. The generator of any preceding claim wherein the selective activation and deactivation of the light sources effects a generation of an animated flame effect.

16. The generator of any preceding claim wherein the height or colour of individual flames within the flame effect may be altered by selective activation of appropriate ones of the light sources.

17. A simulated electric fire including a generator as claimed in any preceding claim, the generator being located within a chassis of the fire, the chassis also housing a fuel bed, the generator being located relative to the fuel bed such that when activated generated flame effects appear to originate from the fuel bed.

18. The fire of claim 17 wherein the generator is enclosed within a chamber, the chamber having at least one partially transparent screen through which a viewer may view the generated flame effects.

19. A generator substantially as hereinbefore described with reference to Figures 1 and 2 or Figures 3 to 5 of the accompanying drawings.