GB2602618A

GB2602618A - Apparatus for simulating combustion

Info

Publication number: GB2602618A
Application number: GB2017644.2A
Authority: GB
Inventors: Mcmahon Zac
Original assignee: CK Fires Ltd
Current assignee: CK Fires Ltd
Priority date: 2020-11-09
Filing date: 2020-11-09
Publication date: 2022-07-13
Anticipated expiration: 2040-11-09
Also published as: GB2602618B; GB202017644D0; WO2022096900A3; WO2022096900A2

Abstract

An apparatus 10 suitable for simulating combustion comprises a semi-reflective screen 8 positioned between a base assembly and an upper assembly. The base assembly comprises a first light source 11a, a first base filter 12a comprising a sheet shaped into ridges and troughs and containing apertures, a second partially transparent base filter 13a, and a translucent base 14a; the upper assembly comprises a second light source 11c, a first upper filter 12c comprising a sheet shaped into ridges and troughs and containing apertures, a second partially transparent upper filter 13c, and a translucent upper wall 14c. A combustion effect is produced by light transmitted through the base and upper assemblies. The apparatus may have a similar rear wall assembly 11b, 12b, 13b, 13c. The semi-reflective screen may be angled towards the back of the apparatus at an angle of 30 to 50 degrees. The light sources may be an LED array displaying an animation and the apertures in the filters may be flame-shaped. An electric heating appliance (1, Fig. 1) is also claimed.

Description

Apparatus for Simulating Combustion The present invention concerns an apparatus for simulating combustion. In particular, the present invention relates to an apparatus for simulating combustion in a heating appliance, such as an electric fire, that provides a realistic, dynamic and three-dimensional combustion effect.

Electric heating appliances, such as electric fires (also known as electric fireplaces, electric stoves and electric heaters), are well-known alternatives to wood-and gas-burning fireplaces.

Known electric heating appliances comprise a heating unit and a flame effect simulator. The heating unit operates to draw in air at ambient temperature and includes heating coils to increase the temperature of the air within the appliance. The heated air, i.e. at temperatures above ambient temperature, is then transferred out of the appliance and back into the room via a fan within the electric heating appliance. Known flame effect simulators, such as that described in United States patent no. US 4,965,707, include a light source, simulated effect means to simulate flames, simulated fire means to simulate a bed of combusting fuel, and a screen on which to view an image of the simulated flames.

The heating unit of such electric heating appliances is controllable, such that a user is able to turn the heater on and off, as well as adjust the temperature of the air that is emitted from the electric heating appliance. Similarly, the flame effect simulator of such electric heating appliances may be controllable, so that a user can turn the simulated flame effect on and oft or adjust the brightness of the simulated flame effect. The heating unit and the flame effect simulator may be independently adjustable, for example so that the simulated flame can be viewed when the electric heating appliance is not required to produce heat.

An example of a three-dimensional flame simulation system for an electric fire is described in Chinese Patent publication no. CN109973913. The flame simulation system includes a projection backboard, simulated charcoal, and a light source projection device, with the light source projection device positioned in a top corner of the electric fire. The light source projection device has a drive motor, a driving wheel, a transparent lens or mirror, a light emitting diode (LED) light board, a corrugated transparent cover, a flame forming plate, a reflector, a housing, and a housing cover. The reflector is located between the LED light board and the transparent mirror. In order to make light transmitted by the corrugated cover form a more realistic flame, the flame forming plate is positioned outside the corrugated cover. The motor drives the wheel, causing the transparent mirror to rotate, and light rays, which penetrate through the corrugated transparent cover, are projected to the projection backboard and the simulated charcoal, so that a dynamic three-dimensional flame shape is formed.

In addition, United States patent publication no. US 2017/0328575 describes a lighting system for an electric fireplace. The lighting system has front and rear projectors which are used to provide the appearance of burning logs within the fireplace. The front and rear projectors each include a light source, which can be an LED array, and a spinner. Light projected from each of the projectors onto the logs forms a three-dimensional flame effect on the logs, with the rotation of the spinners providing a moving effect to the flames.

A further example of an electric fire which is designed to simulate a combustible fuel-burning fireplace is described in United States Patent publication no. US 2002/0168182. A simulated firebox having a top, a bottom, a back and two sides is placed within the fireplace. The fire simulation assembly includes a light source, a light randomiser, a light filter screen and a light diffuser. The light randomiser includes a rotating hollow cylinder having openings through which light can pass. The light filter screen has an opaque area and a coloured translucent area through which light from the light randomiser can pass onto the back of the light diffuser screen. The light diffuser screen has a partially translucent surface on which flames are projected and are visible from the front of the fireplace. The rotating hollow cylinder provides a moving appearance to the flames.

However, each one of the above examples, together with other known fire effect simulators, suffers, inter alia, from two distinct problems: the moving parts, which are responsible for the moving effect of the flames, (i) degrade over time and can require replacement on a periodic basis, and (ii) cause a mechanical noise to be produced which detracts from the desired effect of a real fire.

As such, there is a need to improve the way in which combustion is simulated in order to provide a more realistic, dynamic, three-dimensional combustion effect, and to do so in a silent and more reliable manner.

Accordingly, in accordance with a first aspect of the invention, there is provided an apparatus for simulating combustion, the apparatus comprising: a base assembly; an upper assembly; and a semi-reflective screen positioned between the base assembly and the upper assembly; wherein the base assembly comprises: a first light source; a first base filter comprising a sheet shaped into a series of ridges and troughs, and having a plurality of apertures through which light from the first light source can be transmitted; a second base filter comprising a partially transparent sheet; and an opaque base; wherein the upper assembly comprises: a second light source; a first upper filter comprising a sheet shaped into a series of ridges and troughs, and having a plurality of apertures through which light from the second light source can be transmitted; a second upper filter comprising a partially transparent sheet; and an opaque upper wall; and wherein the base assembly and the upper assembly are configured such that light emitted from the first light source and the second light source is transmitted through the base assembly and the upper assembly to produce a combustion effect within the apparatus.

Surprisingly, it has been found that such an apparatus is able to produce a realistic, dynamic, three-dimensional combustion effect within the apparatus without any moving parts. Indeed, the combination of the base assembly, upper assembly, and semi-reflective screen allows, by way of the respective light sources, filters and opaque screens, a dynamic combustion effect to be viewed within the apparatus. Furthermore, the specific arrangement of the base assembly, upper assembly, and semi-reflective screen facilitates a realistic three-dimensional representation, and the lack of any moving parts means that the apparatus produces its effects in an entirely silent manner. Additionally, since the only active components of the apparatus are the light sources, these are the only components which may require replacement over time.

In an exemplary embodiment, the semi-reflective screen is configured to reflect light emitted from the second light source. In this case, the semi-reflective screen may reflect light emitted from the second light source whilst allowing light from the first light source to be transmitted. In particular, the semi-reflective screen may be positioned at an angle of between 30 and 50 degrees to horizontal, preferably between 35 to 55 degrees to horizontal, and may be angled towards the rear of the apparatus. This arrangement is particularly effective in providing a three-dimensional appearance to the transmitted and reflected light, and thus the combustion effect.

The semi-reflective screen may be composed of a glass or acrylic material. For example, the material may be a toughened clear float glass, a clear pyrolytic coated glass (e.g. a clear glass coated with a metal oxide applied in a pyrolytic process), or a clear acrylic. Preferably, the material is a clear float glass or a CRYLON ® or similar extruded acrylic material.

The apparatus may further comprise a simulated fuel positioned between the semi-reflective screen and the base assembly such that light emitted from the first light source and the second light source is transmitted through the base assembly and the upper assembly to produce a combustion effect on and around the simulated fuel. As such, the simulated fuel may be positioned in a central section of the apparatus above the base assembly, with the upper assembly and semi-reflective screen positioned over it. In this case, the semi-reflective screen may be positioned above the simulated fuel and angled from a front section of the base assembly to an upper section of the rear of the apparatus and/or a rear section of the upper assembly. The simulated fuel may be decorative and may be selected from the group consisting of wood logs, charcoal, pebbles, stones, glass chippings, and slate chippings. In each case, the simulated fuel may be composed of any material, since it is not subjected to any heating. Preferably, the simulated fuel is composed of a ceramic material. The presence of the simulated fuel gives the realistic impression that the particular fuel is combusting within the apparatus.

In another exemplary embodiment, at least one of the first light source and the second light source comprises a light emitting diode (LED) array. Indeed, preferably each one of the first light source and the second light source comprises an LED array. Each LED of the light emitting diode array may be assignable, and may be assignable to display an animation. The animation is designed to illuminate the apparatus with the desired combustion effect and may be a pre-programmed animation or a customisable animation. The animation may vary depending on the assembly in which it is projected by the light sources, since the three-dimensional effect is a combination of the projections from the different perfectives of each assembly, i.e. the animation in the base assembly may be different to the animation in the upper assembly, since it is the combination effect of both assemblies that is important. The animation may also be the same in each assembly.

The first base filter and the first upper filter each comprise a sheet shaped into a series of ridges and troughs. The sheet may be shaped into a series of parallel ridges and troughs, and, in a preferred embodiment, may be provided as a corrugated or concertinaed sheet. A corrugated sheet may have a sinuous or wavelike structure with rounded ridges and troughs, whereas a concertinaed sheet may provide a zigzag-like structure with angular ridges and troughs. These types of three-dimensional arrangement have the advantage of creating dynamic light and shadow effects from the projected light.

In a preferred embodiment, the first base filter and the first upper filter each comprise a concertinaed sheet. For example, the first base filter and the first upper filter may each be provided as a concertinaed sheet in which the average period between ridges of the concertina is from 2 to 10 mm, such as 3 to 7 mm, preferably about 5 mm, and the average amplitude of the ridges and troughs is from 5 to 15 mm, such as 8 to 12 mm, preferably about mm.

The first base filter and the first upper filter may be composed of the same or different materials. Each filter may be composed of a plastic (e.g. an acrylic), metal or alloy material. For example, a steel alloy, which may or may not be electrolytically plated (e.g. Zintec). Preferably, the first base filter and the first upper filter may be composed of a plastic or acrylic material, since these materials provide improved light dissipation effects. The first filters may have a constant thickness of 0.5 to 5 mm, such as 0.5 to 3 mm, preferably 0.7 to 1.2 mm.

The first base filter and the first upper filter are each provided with a plurality of apertures through which light from the respective light sources can be transmitted. Such apertures may be shaped to simulate a specific combustion effect, such as burning flames and/or burning embers. The aperture shapes may differ between the assemblies so as to simulate different combustion effects from each assembly. In a preferred embodiment, the plurality of apertures in the first upper filter are flame-shaped. The plurality of apertures in the first base filter may also be flame-shaped, since this provides both a flame effect where the light is not projected onto a simulated fuel, and a burning ember effect where the light is projected onto and distorted by a simulated fuel.

The apparatus comprises a second base filter and a second upper filter, wherein each may be composed of an extruded plastic material having light scattering properties. For example, the extruded plastic material may contain a plurality of light-scattering inclusions. The light-scattering inclusions may be an inherent structural characteristic of the extruded plastic material, and may provide defined areas of differing light transparency properties. In particular, the extruded plastic material may be a transparent sheet material with a prism structure that spreads/diffuses light into two directions. The prisms may be straight or diagonal depending on the combustion effect that is to be produced. The second filters may have a constant thickness of 2 to 6 mm, preferably 3 to 5 mm. In a particularly preferred embodiment, the extruded plastic material is a clear Salbex pressed PVC sheet (sometimes referred to as Telbex) sold by PAR Group. The benefit of employing this type of second filter is that it can focus and enhance the light projected through the first filters.

The opaque base and the opaque upper wall may each be composed of a glass or plastic material. For example, the material may be a clear or coloured cast polymethyl methacrylate (PMMA). Particularly preferred materials include an extruded PMMA sheet sold under the name Polycasa Crylux Opal Frost Antarctic White 2000 ARD (Opal Frost) and an extruded PMMA sheet sold under the name Polycasa Crylux Seville Orange Frost 1307 ARD (Seville Orange Frost) by Pyramid Display Plastics. Preferably, the opaque base and the opaque upper wall are each composed of the same material, which may have a constant thickness of 2 to 6 mm, such as 3 to 5 mm, preferably about 3 mm. In addition, the opaque base and the opaque upper wall may each have a refractive index of 1.40 to 1.70 (according to ISO 489:1999), preferably 1.45 to 1.55, and a turbidity of 0.5 to 5% (according to ISO 14782), preferably 0.5 to 2.5%.

In a further embodiment, the apparatus further comprises a rear wall assembly, wherein the rear wall assembly comprises: a third light source; a first wall filter comprising a sheet shaped into a series of ridges and troughs, and having a plurality of apertures through which light from the third light source can be transmitted; a second wall filter comprising a partially transparent sheet; and an opaque rear wall; and wherein the base assembly, the upper assembly and the rear wall assembly are configured such that light emitted from the first light source, the second light source and the third light source is transmitted through the base assembly, the upper assembly and the rear wall assembly to produce a combustion effect within the apparatus.

The additional presence of the rear wall assembly further enhances the combustion effect within the apparatus by providing a truly realistic, dynamic, combustion effect. Indeed, the synergy of the base assembly, upper assembly, and semi-reflective screen, by way of the respective light sources, filters and opaque screens, is such that a dynamic, three-dimensional representation is created in an entirely silent manner.

The construction of the rear wall assembly may be the same as the base assembly and/or the upper assembly. As such, the components of the rear wall assembly may have any of the features described in relation to the corresponding components of the base assembly and the upper assembly. For example, the third light source, the first wall filter, the second wall filter and the opaque rear wall may have the same physical features, such as materials and dimensions, as the first and second light sources, the first base filter and the first upper filter, the second base filter and the second upper filter, and the opaque base and opaque upper wall, respectively.

The rear wall assembly may be positioned behind the base assembly and the upper assembly, and in front of the semi-reflective screen. The semi-reflective screen may be angled towards the rear assembly, and light transmitted by the rear assembly may be transmitted through the semi-reflective screen, and not reflected by it, to the viewer.

In a preferred embodiment, the first wall filter may comprise a concertinaed sheet having a plurality of apertures through which light from the third light source can be transmitted. The plurality of apertures in the first upper filter are preferably flame-shaped.

In another preferred embodiment, the second wall filter may be printed on a surface with a matrix of light-blocking dots. The dots may successively increase in volume from one line of the matrix to the next. For example, a dot matrix pattern may be printed onto a surface of the second wall filter, in which the pattern is a grid of regularly-spaced dots in two directions. In one of the directions, the dots may successively increase in volume from one line of dots to the next, and may progress from an area having no dots to an area where the dots essentially create a solid area. The highest volume dots may be located in the top row of the matrix pattern and then fade towards the bottom row of dots, whereby the fading dot matrix pattern helps to block out light spillage.

In use, light emitted from the first light source is projected onto the opaque base to provide the desired combustion effect. This light Is viewed by the viewer through the semi-reflective screen, i.e. this light is transmitted by the semi-reflective screen and not reflected by it. Similarly, when present, light emitted from the third light source, in use, is projected onto the opaque rear wall to provide the desired combustion effect. This light is also viewed by the viewer through the semi-reflective screen, since it is not reflected by it. In contrast, light emitted from the second light source, in use, is projected onto the opaque upper wall, and is then reflected forwards by the semi-reflective screen to the viewer to provide the desired combustion effect. The combination of these optical effects is a realistic, dynamic, three-dimensional combustion effect within the apparatus.

In combination, the opaque base of the base assembly, the opaque rear wall of the rear wall assembly, when present, and the opaque upper wall of the upper assembly may define an internal chamber in the apparatus in which the semi-reflective screen is positioned. In embodiments where a simulated fuel is present, the simulated fuel may also be positioned in the internal chamber below the semi-reflective screen. With this arrangement, the combination of optical effects provided by the base assembly, rear wall assembly, when present, and upper assembly is a combustion effect that provides the impression that the simulated fuel is combusting on and around the fuel.

In accordance with a second aspect of the invention, there is provided a heating appliance comprising an electric heating assembly and an apparatus for simulating combustion according to the first aspect of the invention.

As will be appreciated, the apparatus for simulating combustion may have any of the features of the apparatus described in relation to the first aspect of the invention, and any combination of those features. The heating appliance is preferably an electric fire, which may have an output of up to 1000W or 1500W.

In accordance with a third aspect of the invention, there is provided an apparatus for simulating combustion which has the same features as the apparatus for simulating combustion according to the first aspect of the invention, but wherein the base assembly is omitted. In this case, the apparatus comprises: an upper assembly; and a semi-reflective screen positioned below the upper assembly; wherein the upper assembly comprises: a light source; a first upper filter comprising a sheet shaped into a series of ridges and troughs, and having a plurality of apertures through which light from the light source can be transmitted; a second upper filter comprising a partially transparent sheet; and an opaque upper wall; and wherein the upper assembly is configured such that light emitted from the light source is reflected by the semi-reflective screen to produce a combustion effect within the apparatus.

In this third aspect of the invention, the upper assembly and the semi-reflective screen cooperate to create the impression of a realistic, dynamic combustion effect within the apparatus without any moving parts. The addition of the base assembly and optionally also the rear wall assembly, as in the first aspect of the invention, further enhances the combustion effect within the apparatus.

As will be appreciated, the apparatus for simulating combustion of the third aspect of the invention may have any of the features of the apparatus described in relation to the first aspect of the invention, and any combination of those features. It may also form part of a heating appliance as described in relation to the second aspect of the invention.

An example apparatus for simulating combustion and an example heating appliance according to the present invention will now be described with reference to the accompanying Figures in which: Figure 1 is a perspective view of a heating appliance according to an embodiment of the present invention; Figure 2 is a schematic representation of an apparatus for simulating combustion according to an embodiment of the present invention; Figure 3a is an exploded perspective view of an apparatus for simulating combustion according to an embodiment of the present invention; Figure 3b is an exploded front view of an apparatus for simulating combustion according to an embodiment of the present invention; Figure 3c is an exploded side view of an apparatus for simulating combustion according to an embodiment of the present invention; Figure 4 is a perspective view of an LED array and a filter for use in an apparatus for simulating combustion according to an embodiment of the present invention; and Figure 5 is a dot matrix print pattern for use in an apparatus for simulating combustion according to an embodiment of the present invention.

Referring to Figure 1, there is a heating appliance, in the form of an electric fire 1. The electric fire 1 has an external housing defined by an upper panel 2, two side panels 3,4, a rear panel (not shown), a base panel Sand a front panel 6. The front panel comprises a non-transparent surrounding section 6a, which provides a structural connection to the adjacent panels, and a transparent window 6b, through which the simulated combustion effect can be viewed. The electric fire 1 further comprises an electric heating unit 7 in an upper section of the electric fire 1. The electric heating unit 7may provide a heat output of up to 1000W or 1500W. Within the electric fire 1 is an apparatus for simulating combustion according to the invention (not fully shown in Figure 1), which comprises a semi-reflective screen 8 positioned over a simulated fuel 9, in this case a set of logs. The simulated fuel 9 is decorative and is not subjected to any heat generated by the electric heating unit 7, which means that it can be composed of any suitable material.

The transparent window 6b may be composed of a glass material. The optical properties of the glass material may be tailored to enhance the viewing characteristics of the simulated combustion effect. In particular, a glass material may be employed which minimises luminous surface reflections, thereby avoiding glare that distorts the appearance of the combustion effect to the viewer. The glass material may also have high-level transmission properties in the visible spectrum, meaning that a high proportion of light is transmitted through the glass from the combustion simulation apparatus. The glass material may also have high impact and scratch resistance properties, by way of chemical toughening processes and/or chemical coating. A preferred example of a glass material that can used as the transparent viewing window 6b is that produced and sold by Schott AG under the trade name Conturan®. A particularly preferred product in this series of products is Conturan Magic®.

The heating unit 7 is operable to generate heat and may have a motor and a fan (not shown). The motor may be configured to increase the temperature of air that is drawn into the electric fire 1 and the fan may be configured to push the heated air out of the electric fire 1, as is known in the art.

The electric fire 1 may also compromise a control unit (not shown) that is configured to receive signals from an external control unit (not shown), for example a temperature sensor or thermostat. The control unit may be further configured to receive signals from a user control panel or interface (not shown) that is provided on the electric fire 10. The control unit may also be configured to receive signals from a remote device (not shown), such as a handheld remote control or a client device (e.g. mobile telephone, personal computer or tablet), either directly (e.g. via infrared or Bluetooth Low Energy technology) or by way of a remote server (e.g. a cloud-based server) and/or local network (e.g. via Wi-Fi technology). The client device may have an associated application that allows the client to remotely change the settings of the electric fire 1, whether that be heating settings, combustion simulation effects or both. The application may have compatibility with other smart devices and applications, such as Amazon Alexa and Google Home, for voice-activated control.

As schematically illustrated in Figure 2, there is an apparatus for simulating combustion 10 according to the invention. The combustion simulating apparatus 10 comprises three assemblies: a base assembly 11a, 12a, 13a, 14a; a rear wall assembly 11b, 12b, 13b, 14b; and an upper assembly 11c, 12c, 13c, 14c. Each assembly comprises a light source 11a, 11b, 11c, which may be an LED array of assignable LEDs, a filter comprising a sheet shaped into a series of parallel ridges and troughs 12a, 12b, 12c, a second filter comprising a partially transparent sheet 13a, 13b, 13c, which may possess light diffusion properties, and an opaque screen 14a, 14b, 14c, onto which light from the respective light sources may be projected. The apparatus further comprises a semi-reflective screen 8, which is positioned over a simulated fuel 9.

In the case of the base assembly, light is generated by the first light source 11a, in use, which is oriented in such a way as to project the light upwards towards the opaque base 14a. For example, the first light source 11a may be positioned in a horizontal plane with the light source facing upwards. The first light source 11a may convey light in varying colours and intensities in the form of an animation which mimics the desired combustion effect.

Light from the first light source 11a is projected onto the first base filter 12a, which comprises a sheet shaped into a series of parallel ridges and troughs, such as a concertinaed sheet. The first base filter 12a is impervious to light with the exception of a plurality of apertures (not shown in Figure 2), through which light from the first light source ha may be transmitted. The physical structure of the first base filter 12a, i.e. the series of parallel ridges and troughs, together with the plurality of apertures, has the effect of creating a series of shadows and shapes in the transmitted light, and gives the appearance that the projected light is moving.

Due to the varying optical effects from the first light source 11a and the three-dimensional shape of the apertures, the first base filter 12a splits the light so that dynamic shapes, such as flames, are created that have no definitive form.

The moving split and scattered light then passes through the second base filter 13a which comprises a partially transparent sheet. The optical properties of the second base filter 13a are such that it corrects and defines certain element shapes and intensities of the projected light. For example, the second base filter 13a may possess light scattering properties that, due to the already split and scattered light transmitted through the first base filter 12a, then corrects the projected light so that certain elements are focused onto the opaque base 14a.

Preferably, the second base filter 13a is composed of a clear Salbex pressed PVC sheet (sometimes referred to as Telbex) sold by PAR Group, which is a transparent sheet material having a prism structure that spreads/diffuses light into two directions.

The opaque base 14a functions as a screen onto which light is projected. Due to the varying light effects created by the first light source 11a, the three-dimensional structure of the first base filter 12a and its associated apertures, and the corrective light scattering effects of the second base filter 13a, a moving combustion effect is presented on opaque base 14a with varying brightness and colouring. Notably, this is achieved by varying the light projected by the first light source 11a, and without any moving parts. The light projected onto opaque base 14a can be seen by a viewer through the semi-reflective screen 8.

In the example illustrated in Figure 2, a simulated fuel 9 is positioned on top of opaque base 14a. In this arrangement, the light projected onto opaque base 14a provides a combustion effect from beneath the simulated fuel 9, which can present on or around the simulated fuel as flames or burning embers. The simulated fuel 9 may be any type of decorative fuel, such as a set of wooden logs, charcoal, stones, pebbles, glass chippings, or slate chippings. The material used for the simulated fuel 9 is not limited in the sense that it is not subjected to any heat in applications with an accompanying heating unit. This is because the combustion simulation apparatus 10 is separate to any such heating units. Nevertheless, a preferred material for the simulated fuel 9 is a ceramic. In a preferred embodiment, the simulated fuel 9 is a decorative set of ceramic logs.

The rear wall assembly 11b, 12b, 13b, 1413 has the same features as the base assembly 11a, 12a, 13a, 14a and functions in the same way. As such, the third light source 11b corresponds to the first light source 11a, the first base filter 12a corresponds to the first wall filter 12b, the second base filter 13a corresponds to the second wall filter 13b, and the opaque rear wall 14b corresponds to the opaque base 14a. This combination of features thus provides similar visual effects, which are projected onto the opaque rear wall 14b, and can be viewed by the viewer through the semi-reflective screen 8.

The upper assembly 11c, 12c, 13c, 14c has the same features as the base assembly 11a, 12a, 13a, 14a and the rear wall assembly 11b, 12b, 13b, 14b, and functions in the same way. However, the main difference with the upper assembly 11c, 12c, 13c, 14c is that light projected from the second light source 11c, through the first upper filter 12c and the second upper filter 13c onto the opaque upper wall 14c, is viewed by the viewer in the semi-reflective screen 8. As such, in contrast to the opaque base 14a and the opaque rear wall 14b, the semi-reflective screen 8 reflects the light from the opaque upper wall 14c rather than transmitting it. By way of this combination of assemblies, the viewer sees a realistic, three-dimensional combustion effect within the apparatus 10, which appears to be in and around the simulated fuel 9.

The semi-reflective screen 8 is angled towards the rear wall assembly 11b, 12b, 13b, 14b. In particular, the semi-reflective screen 8 is angled towards the rear wall assembly 11b, 12b, 13b, 14b from a front section of the base assembly 11c, 12c, 13c, 14c, meeting the rear wall assembly 11b, 12b, 13b, 14b at an upper section thereof. In order to achieve the reflection of light from the opaque upper wall 14c, the semi-reflective screen 8 may be positioned at an angle of 35 to 45 degrees to horizontal. This type of angle is particularly effective for reflecting light from the upper assembly 11c, 12c, 13c, 14c to a viewer in front of the apparatus 10 or electric fire 1. In the example shown in Figure 2, the semi-reflective screen 8 has an angled section 8a representing the main viewing area of the apparatus and a non-angled section 8b, such as a vertical section, which is positioned at a lower end of the screen 8 adjacent to the base assembly 11c, 12c, 13c, 14c and the simulated fuel 9. In this example, the semi-reflective screen 8 is a substantially flat screen in order to uniformly reflect light from the upper assembly 11c, 12c, 13c, 14c; however, in other embodiments, it may have a curved structure in order to reflect and focus the light in order to achieve a particular visual perspective for the viewer.

With reference to Figures 3a, 3b and 3c, there is a specific example of an apparatus 10 for simulating combustion according to the invention. In this implementation, each one of the first light source 11a, the third light source 11b and the second light source 11c comprises LED arrays comprising 256 RGB colour assignable LEDs. The LEDs are in an 8 x 32 grid format. Indeed, each assembly comprises two 256 RGB colour assignable LED arrays which are configured to display an animation that provides the desired combustion effect. The first light source 11a and the second light source 11c have two such LED arrays in an end-to-end arrangement, thereby creating an 8 x 64 grid, whereas the third light source 11b has two such LED arrays in a side-by-side arrangement, thereby creating a 16 x 32 grid.

The base assembly 11a, 12a, 13a, 14a is held in the apparatus 10 by bracket 15, which has a lower part 15a and an upper part 15b. Similarly, the rear assembly 11b, 12b, 13b, 14b is held by bracket 16, and the upper assembly 11c, 12c, 13c, 14c is held in position by bracket 18.

The first wall filter 12b is a concertinaed sheet which runs along the entire length of the rear wall assembly. At varying locations of the first wall filter 12b are apertures 17 extending through the entire sheet such that light from the second light source 11b can be transmitted. The apertures 17 are flame-shaped in order to provide a flickering flame appearance to the combustion effect. Similarly, the first upper filter 12c and the first base filter 12a are also concertinaed sheets with a plurality of flame-shaped apertures 17. Other types of aperture shapes can be used depending on the type of combustion effect desired.

In Figures 3a, 3b and 3c, the second base filter 13a and the opaque base 14a are shown sandwiched together. This is the same for the corresponding components of the rear assembly and the upper assembly. In other embodiments, these components may be separated by a distance necessary to achieve the desired combustion effect.

As will be appreciated from Figure 3c, the rear wall assembly 11b, 12b, 13b, 14b is presented in a substantially vertical orientation such that light from the assembly is projected forwards towards the viewer. Conversely, the base assembly 11a, 12a, 13a, 14a is oriented in a substantially horizontal manner with the assembly facing upwards such that light from the assembly is projected up towards the simulated fuel 9. The upper assembly 11c, 12c, 13c, 14c is also presented in a substantially horizontal orientation, but faces downwards such that light from the assembly is projected down onto the semi-reflective screen 8. The second upper filter 13c and the opaque upper wall 14c are angled slightly towards the rear assembly in bracket 18 compared to the second light source 11c and the first upper filter 12c.

The simulated fuel 9 is positioned within a chamber created by the semi-reflective screen 8, the opaque base 14a and the opaque rear wall 14b. Indeed, the third light source 11b and the first wall filter 12b are positioned behind the simulated fuel 9 such that the projected light appears on and around the simulated fuel 9. Similarly, the first light source 11a and the first base filter 12a are positioned under the simulated fuel 9, and the second light source 11c and the first upper filter 12c are positioned above the simulated fuel 9 for the same reason.

Figure 4 shows a representation of the second light source 11b and the first wall filter 126 according to the invention. The features of these components are the same as those of the corresponding components in the base assembly and the upper assembly.

In this case, an LED array of the third light source 11b is shown, which comprises two 8 x 32 LED arrays. Each array has 256 individual RGB colour LEDs 19, each of which is assignable, thereby giving a total of 512 LEDs. The LED arrays are connected to a control unit (not shown), which runs an animation of random colours associated with a burning fire. The animation may be pre-programmed or may be customisable. Indeed, the apparatus may be configured with a selection of different animations, each of which provides a different type of burning effect, such as a flame effect, a burning ember, an aurora effect and/or a colour spectrum effect. The animation may also be customisable in terms of the desired brightness and speed of the burning effect.

The first wall filter 12b has the form of a concertinaed sheet. Extending through the sheet are a series of flame-shaped apertures 17. The apertures 17 take various forms that mimic the different sizes and shapes of flames in a natural fire. As the apertures 17 are presented on the three-dimensional concertina shape, the changing light effects (e.g. brightness and colouring) provided by the animated light source 11b (not shown in Figure 4) give rise to changing light and shadow effects projected through the first wall filter 12b. This results in an overall impression of a moving flame effect, without any moving parts. The same result is achieved in the same manner by the first base filter 12a and the first upper filter 12c, together with their respective light sources 11a, 11c.

As described in relation to Figure 2, the second base filter 13a, the second wall filter 13b and the second upper filter 13c each comprise a partially transparent sheet. The partially transparent sheets have the effect of correcting light scattering effects of the respective first filters 12a, 12b and 12c and focus certain elements onto the respective opaque screens 14a, 14b and 14c. In order to further enhance the realism of the projected combustion effect, the second wall filter 13b may have a pattern printed on its surface. For example, as shown in Figure 5, a dot matrix pattern 20 is applied to its surface which comprises a grid of light-blocking dots 21. In this case, the dots 21 are presented in a grid format in which the dots progress from lines of lower volume dots 21a to dots of progressively larger volumes 21b, 21c, until the dots 21d are of a volume that blocks almost all light from passing through the filter. This type of pattern has the advantageous effect of applying a fading effect to the projected light. Preferably, the dots 21d of largest volume are provided at the top end of the filter and progressively fade in volume downwards towards the lower volume dots 21c, 21b and 21a. The lower volume of dots towards the bottom of the dot matrix pattern creates a fading effect. Other printed patterns and shapes may be used to tailor the combustion effect.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation.

Although the invention has been illustrated and described with respect to one or more implementations, equivalent alterations and modifications will occur or be known to others skilled in the art upon the reading and understanding of this specification and the accompanying figures. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Thus, the breadth and scope of the present invention should not be limited by any of the above described embodiments. Rather, the scope of the invention should be defined in accordance with the appended claims and their equivalents.

Claims

Claims 1. An apparatus for simulating combustion, the apparatus comprising: a base assembly; an upper assembly; and a semi-reflective screen positioned between the base assembly and the upper assembly; wherein the base assembly comprises: a first light source; a first base filter comprising a sheet shaped into a series of ridges and troughs, and having a plurality of apertures through which light from the first light source can be transmitted; a second base filter comprising a partially transparent sheet; and an opaque base; wherein the upper assembly comprises: a second light source; a first upper filter comprising a sheet shaped into a series of ridges and troughs, and having a plurality of apertures through which light from the second light source can be transmitted; a second upper filter comprising a partially transparent sheet; and an opaque upper wall; and wherein the base assembly and the upper assembly are configured such that light emitted from the first light source and the second light source is transmitted through the base assembly and the upper assembly to produce a combustion effect within the apparatus.
2. The apparatus according to claim 1, further comprising a rear wall assembly, wherein the rear wall assembly comprises: a third light source; a first wall filter comprising a sheet shaped into a series of ridges and troughs, and having a plurality of apertures through which light from the second light source can be transmitted; a second wall filter comprising a partially transparent sheet; and an opaque rear wall; and wherein the base assembly, the upper assembly and the rear wall assembly are configured such that light emitted from the first light source, the third light source and the third light source is transmitted through the base assembly and the rear wall assembly to produce a combustion effect within the apparatus.
3. The apparatus according to claim 1 or claim 2, wherein the semi-reflective screen is configured to reflect light emitted from the second light source.
4 The apparatus according to any preceding claim, wherein the semi-reflective screen is positioned at an angle of between 30 and 50 degrees to horizontal and is angled towards the rear of the apparatus.
5. The apparatus according to any preceding claim, wherein the semi-reflective screen is composed of a glass or acrylic material.
6. The apparatus according to any preceding claim, wherein the apparatus further comprises a simulated fuel positioned between the semi-reflective screen and the base assembly such that light emitted from the first light source and the second light source is transmitted through the base assembly and the upper assembly to produce a combustion effect on and around the simulated fuel.
7 The apparatus according to claim 6, when it is dependent upon any one of claims 2 to 5, wherein the simulated fuel is positioned between the semi-reflective screen and the base assembly and in front of the rear assembly such that light emitted from the first light source, the second light source and the third light source is transmitted through the base assembly, the rear wall assembly and the upper assembly to produce a combustion effect on and around the simulated fuel.
8. The apparatus according to any preceding claim, wherein at least one of the first light source and the second light source comprises a light emitting diode array.
9. The apparatus according to claim 8, wherein each light emitting diode of the light emitting diode array is assignable.
10. The apparatus according to claim 9, wherein each light emitting diode of the light emitting diode array is assignable to display an animation.
11. The apparatus according to claim 10, wherein the animation is a pre-programmed animation or a customisable animation.
12. The apparatus according to any preceding claim, wherein the first base filter and the first upper filter are each provided as a corrugated or concertinaed sheet.
13. The apparatus according to claim 12, wherein the first base filter and the first upper filter are each provided as a concertinaed sheet in which the average period between ridges of the concertina is from 2 to 10 mm and the average amplitude of the ridges and troughs is from 5 to 15 mm.
14. The apparatus according to any preceding claim, wherein the first base filter and the first upper filter are each composed of a plastic, metal or alloy material.
15. The apparatus according to any preceding claim, wherein the plurality of apertures in each of the first base filter and the first upper filter are shaped to simulate a specific combustion effect.
16. The apparatus according to claim 15, wherein the plurality of apertures in each of the first base filter and the first upper filter are flame-shaped.
17. The apparatus according to any preceding claim, wherein the second base filter and the second upper filter are each composed of an extruded plastic material having light scattering properties.
18. The apparatus according to any one of claims 2 to 17, wherein the second wall filter is printed on a surface with a matrix of light-blocking dots that successively increase in volume from one line of the matrix to the next.
19. The apparatus according to any preceding claim, wherein the opaque base and the opaque upper wall are each composed of a glass or plastic material.
20. The apparatus according to any preceding claim, wherein the opaque base and the opaque upper wall each have a refractive index of 1.40 to 1.70, according to ISO 489:1999, and a turbidity of 0.5 to 5%, according to ISO 14782.
21. A heating appliance comprising: an electric heating assembly; and an apparatus for simulating combustion according to any one of the preceding claims.
22. The heating appliance according to claim 21, wherein the heating appliance is an electric fire.