GB2361763A

GB2361763A - Fire Simulation Apparatus

Info

Publication number: GB2361763A
Application number: GB0007976A
Authority: GB
Inventors: Colin Edwards
Original assignee: Gazco Ltd
Current assignee: Gazco Ltd
Priority date: 2000-04-01
Filing date: 2000-04-01
Publication date: 2001-10-31
Also published as: GB0007976D0

Abstract

A screen 3 has a composite image of a fire 11, and a lenticular screen 10 superimposed on the image whereby the perceived image as viewed through the screen changes as the viewing position changes. The image is translucent and a light source back-lights the screen through a flicker generating shadow mask such as a moving spinner, ribbons or flags to simulating an effect of moving flames. A static shadow mask 12 may be included to generate an interference pattern with the moving mask. The screen can be used to create a 3D or moving image of a fire. A backing sheet 12 adds structural rigidity to the viewing screen.

Description

2361763 1 FIRE SIMULATION APPARATUS

TECHNICAL FIELD OF THE INVENTION

This invention relates to fire simulation apparatus, particularly (without limitation) for use in situations where the available depth is restricted such as in some kinds of space heater.

BACKGROUND

In recent years a great deal of time and effort has been spent on devising realistic and aesthetically pleasing displays which simulate the appearance of a solid fuel fire, e.g. for use in electric fires, although very few have achieved commercial acceptance. In general, a moulding is used to simulate a fuel bed and an image of flames is generated on a flat screen positioned above the moulding such that the flames appears to emanate from the fuel bed. However, the realism of the display is limited by the fact that the screen essentially creates a two-dimensional display. It has been suggested to use a hologram to generate a three-dimensional image of flames. Holograms are created by lasers and are printed on very thin metallic or transparent sheets. They rely on light interference patterns to 2 generate three dimensional images, and some kinds of hologram must be illuminated by coherent light. Holograms possess a characteristic rainbow sheen (like the reflection in a puddle with a film of oil) and are usually of dull appearance.

The present invention seeks to provide a new and inventive form of fire simulation apparatus SUMMARY OF THE INVENTION

The present invention proposes fire simulation apparatus which incorporates:

- a screen having a composite image of a fire and a lenticular screen superimposed on the image whereby the perceived image as viewed through the screen changes as the viewing position changes; and - flicker generating means for simulating an effect of moving flames.

The screen can be used to create an image of a fire incorporating (without limitation) solid fuel such as logs and coals, a grate, fire bricks, a fire surround and any other components which are normally found in the immediate surroundings of a solid fuel fire. The screen can still be positioned above a solid fuel bed moulding if desired. The resulting display is much clearer and brighter than images formed by holograms.

Lenticular screens are formed of optical grade plastic. The surface away from the composite image is formed with a multiplicity of small magnifying 3 lenses which are usually formed as a series or parallel ribs of planoconvex cross section. The composite image is formed by dividing up each frame (an individual component image) into narrow stdps which are initially of the same width as the lenses. The strips are then transversely compressed and interleaved. When the image is viewed through the lenticular screen the lenses magnify the strips so that they appear to be of normal width without intervening gaps. Viewing the screen from different angles causes different frames to come into view so that the image appears to change. The changing image is usually best seen by moving transverse to the direction of the ribs. Nowadays such composite images are easily generated by computer, and typically up to 40 or 50 frames may be combined into a single composite image. The original frames may be entirely computer-generated or they may be images taken from a real or simulated fire.

It may be possible to generate composite images and screens which will present a changing image when moving in either of two mutually transverse directions.

At least two different kinds of composite image can be generated for use in the present invention. In one kind of composite image the component frames capture different views of an article (in this case a fire) from different angles. In other words, the individual frames in the composite image have a spatial relationship. Such images are useful for creating a pseudo three dimensional (313) effect so that if, for example, the lenticular screen has vertical ribs an observer will perceive different slightly views of the fire in both eyes giving the illusion of depth. If the lenses extend horizontally a similar effect of depth can be perceived as an observer sits down, for example. A realistic illusion of depth can thus be created even in a very restricted volume.

4 A second kind of composite image is formed by viewing the article at different moments in time so that the frames have a temporal relationship. Such composite images are useful for giving an effect of movement so that if, for example, the lenses extend vertically and the observer moves across a room, flames can appear to move or "dance" above the fire in the manner of a real solid fuel fire.

In order to further enhance the realism of the display it is preferred to use a translucent image in combination with a light source for backlighting the image. Thus, the fire can be made to glow and emit light in the manner of a real fire.

It is not essential for the image to incorporate flames since these can be created by the flicker generating means. Such flicker generating means can be of any known kind. For example, a moving shadow mask can be used behind the screen, such as an array of vertical ribbons or flags, or a spinner. The mask could be moved by a fan or by air convection created by a heat source such as a lamp or a space heater. A combination of shadow masks could be used to form flickering patterns. For example, a static shadow mask can be interposed between the back light source and the composite image. The static mask could, for example, take the form of an opaque screen containing windows (i.e. transparent areas or apertures).

The fire simulation apparatus can be incorporated in a heating appliance such as an electric fire or a stove.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings:

Figure 1 is a vertical front-rear section through an electric fire incorporating fire simulation apparatus in accordance with the invention; and Figure 2 is an exploded view of the front viewing screen of the fire simulation apparatus.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring firstly to Fig. 1, the fire comprises a sheet metal casing 1 forming an internal compartment or light box 2 located behind a front viewing screen 3. An electric fan heater 4 is mounted at the top of the casing, although it could be mounted at the bottom or in any other suitable position. On front of the lower portion of the light box 2, below the screen 3, there is a simulated fuel bed 5 resembling burning coals, logs or other solid fuel. Immediately on front of the fuel bed 5 there may be a decorative fretwork 6 6 resembling a grate front. The light box 2 contains a light source 7 (e.g. a lamp) and may be provided with a pivotally mounted apertured canopy 8, usually known as a "spinner", which revolves in air convection currents created by heat from the lamp 7 to create a flickering effect.

Referring to Fig. 2, the viewing screen 3 comprises, from front to rear, a transparent lenticular screen 10 (as described above), a composite image 11, an optional opaque shadow mask layer 12, and a backing sheet 13. The image 11 depicts a fire box containing glowing solid fuel which is positioned to integrate with the fuel bed 5. The image includes flames which are shaped and positioned such that they appear to emanate from the fuel bed. The image may contain additional elements such as a fire surround if desired. Various details, arrangements and options for the lenticular screen 10 and image 11 are discussed in depth above and for brevity will not be repeated here.

The shadow mask 12 (when present) may have an opaque area 20 formed by screen printing, a layer of card etc., with transparent windows 21 shaped as flames. The backing sheet 13 adds structural rigidity to the viewing screen and may also act as a carrier for the shadow mask layer 12. The backing sheet may be formed of clear, translucent or colour-tinted acrylic sheet, for example.

Even when the lamp 7 is not operational the viewing screen creates a bright realistic three dimensional or moving image of flames which appear to emanate from the fuel bed. When the lamp emits light the flames become illuminated and appear to emit light, and the varying shadows cast by the 7 spinner 8 enhance the movement of the flames and may create varying patterns with the apertures in the shadow mask 12 (when present) to create a more realistic flickering effect.

Although a single viewing screen assembly is most convenient the shadow mask could, if desired, be mounted separately behind the backing sheet 13. The spinner could be replaced by a curtain or ribbons or an array of flags, as discussed above.

Although the above example describes an electric fire the fire simulation apparatus could be applied to other forms of heating appliance such as a stove or it could be used solely for visual effect.

Claims

It will be appreciated that the features disclosed herein may be present

in any feasible combination. Whilst the above description lays emphasis on those areas which, in combination, are believed to be new, protection is claimed for any inventive combination of the features disclosed herein.

8 CLAIMS 1. Fire simulation apparatus which incorporates:

- a screen having a composite image of a fire, and a lenticular screen superimposed on the image whereby the perceived image as viewed through the screen changes as the viewing position changes; and - flicker generating means for simulating an effect of moving flames.
2. Fire simulation apparatus according to Claim 1, in which the lenticular screen is formed of plastic and includes a multiplicity of magnifying lenses formed on a surface away from the composite image.
3. Fire simulation apparatus according to Claim 2, in which the lenses are formed as a series or parallel ribs of piano-convex cross section.
4. Fire simulation apparatus according to Claim 3, in which the lenses extend substantially vertically.
5. Fire simulation apparatus according to Claim 3, in which the lenses extend substantially horizontally.
6. Fire simulation apparatus according to any preceding claim, in which the composite image includes a plurality of images of a fire taken from different positions to create a pseudo-3D effect.

9
7. Fire simulation apparatus according to any of Claims 1 to 5, in which the composite image includes a plurality of tempo rally-spaced images of a fire to create an illusion of movement.
8. Fire simulation apparatus according to any preceding claim, in which the composite image is translucent and the apparatus includes a light source for back-lighting the image.
9. Fire simulation apparatus according to Claim 8, in which the flicker generating means includes a moving shadow mask interposed between the light source and the composite image.
10. Fire simulation apparatus according to Claim 9, in which the moving shadow mask includes an array of vertical ribbons.
11. Fire simulation apparatus according to Claim 9, in which the moving shadow mask includes an array of flags.
12. Fire simulation apparatus according to Claim 9, in which the moving shadow mask includes a spinner.
13. Fire simulation apparatus according to any of Claims 9 to 12, in which the moving shadow mask is moved by a fan.
14. Fire simulation apparatus according to any of Claims 9 to 12, in which the moving shadow mask is moved by air convection created by a heat source.
15. Fire simulation apparatus according to any of Claims 8 to 14, in which the flicker generating means includes a static shadow mask interposed between the light source and the composite image.
16. Fire simulation apparatus according to Claim 15, in which the static shadow mask includes an opaque screen containing windows.
17. A heating appliance incorporating fire simulation apparatus according to any preceding claim.
18. Fire simulation apparatus substantially as described with reference to the drawings.
19. A heating appliance incorporating fire simulation apparatus substantially as described with reference to the drawings