WO2000031464A1

WO2000031464A1 - Flame effect assemblies

Info

Publication number: WO2000031464A1
Application number: PCT/GB1999/003878
Authority: WO
Inventors: Keith Jonathan Stokes; David Alan Perry
Original assignee: Valor Limited
Priority date: 1998-11-25
Filing date: 1999-11-23
Publication date: 2000-06-02
Also published as: EP1133658B1; ATE239191T1; DE69907504D1; EP1133658A1; AU1282200A

Abstract

The present specification discloses a flame effect assembly comprising a drum (3), having a longitudinal axis about which the drum (3) is arranged to, in use, be rotated, the drum (3) being capable of at least partially transmitting light therethrough transverse to said longitudinal axis, with means (19, 23) being incorporated in the drum (3) for producing shadows in light from a light source (7), which is transmitted through the drum (3) generally transverse to said longitudinal axis, and onto a screen (11).

Description

DESCRIPTION

FLAME EFFECT ASSEMBLIES

The present invention relates to a flame effect assembly for use in producing

a realistic flame effect.

More particularly, the present invention relates to a flame effect assembly

primarily for use in a space heater such as an electric fire for use in, for example, a

private dwelling to provide heat as and when required, with the added realism of a

real fire by virtue of the flame effect assembly.

Many known electric fires incorporate an effect to replicate a flame effect.

An extensive range of flame effect concepts have been used, and these have been

often quite complex and thus expensive. Further, these known flame effect concepts

can require the electric fire to have a considerable depth, this being considered

undesirable for aesthetic reasons, ease of installation especially in fire surrounds, and

as regards cost due to the amount of material eg. metal, required for the construction.

A slim construction is considered desirable so that the fire can fit snugly and cleanly

into a shallow rebated fire surround, against a wall or in a shallow recess, to improve

the aesthetic appearance of the installation, and to make the construction cost

effective.

For many years flame effects have been used involving a reflecting means of

one form or another, which is slowly rotated to give an effect as the reflected light

falls onto a screen which is viewed either directly or through a front glass panel.

Such arrangements are disclosed in British Patent Specification Nos. 450941, 164143, 1272644 and US Patent Specification No. 5642580. These involve the use

of coloured bulbs or other means of producing yellow/red colours associated with

flames.

An aim of the present invention is to provide a flame effect assembly which

is realistic and which, when used in, for example, an electric fire, enables the fire to

have a slim and cost effective construction.

According to the present invention there is provided a flame effect assembly

comprising a drum having a longitudinal axis about which the drum is arranged to,

in use, be rotated, the drum being capable of at least partially transmitting light

therethrough from a light source, transverse to said longitudinal axis, with means

being incorporated in the drum for producing shadows in the light which is

transmitted through the drum generally transverse to said longitudinal axis, and onto

a screen.

In one embodiment of the present invention the drum is arranged with said

longitudinal axis horizontal, with one end region of the drum being connected to

motor means eg. an electric motor, for rotating the drum at a constant speed about the

longitudinal axis, and the other end mounted for free rotation by virtue of a spring

mounting which facilitates withdrawal. Alternatively the motor means may be

arranged to rotate the drum at a varying rotational speed to further enhance the flame

effect produced by the present invention.

Further, the longitudinal axis of the drum is preferably, though not essentially,

the central axis of the drum. By having the drum rotatable about an eccentrically positioned longitudinal axis, whilst bearings can be undesirably loaded, the flame

effect may be further varied to advantage.

The drum itself is preferably transparent, and preferably made from a

transparent plastics material, eg. a polycarbonate material, the said means for

producing shadows being preferably formed by a predetermined random pattern

carried by the drum, the pattern comprising apertures defined by a closed network

which can be provided by paint of any desired colour. Said network may be totally

opaque so that no light passes therethrough or translucent to allow an amount of light

therethrough. Further the apertures in the pattern may, if desired have a coloured hue

eg. beige or amber, which can, if required, vary in density gradually over the drum

eg. diagonally, to soften and enhance the flame effect.

To produce the required pattern and the coloured hue the outside surface of

the drum which may be solid or hollow, may be painted, or appropriately etched, and

also painted to produce the hue, if required. Alternatively, the drum which is

preferably hollow, may be painted and/or etched on its inside and/or outside surface

to produce the required pattern. Further, the pattern and hue if required, may be

alternatively produced on a flexible transparent sheet eg. acetate, and folded into a

generally cylindrical form to be then inserted into the hollow drum, the inherent

resilience of the normally planar sheet biassing the sheet against the inner wall of the

drum. Preferably the sheet is approximately of dimensions which fit the length and

internal configuration of the drum.

To further enhance the flame effect produced by the pattern described here above, a spiral strip of translucent material eg. red in colour, may be provided on the

drum again, for example, by painting the outside or inside surface of the drum with

a suitable paint or ink, or formed actually in the material of the drum, such as when

the drum is made of a polycarbonate or other plastics material. Alternatively a spiral

of translucent coloured eg. red, material eg. a plastics material, may be located on the

inside surface of the drum and either secured in position by a suitable adhesive, drum

end caps, or by its inherent flexibility due to its spiral configuration, or located

between the inside surface of the drum and the said transparent sheet comprising the

said pattern, the transparent sheet holding the said spiral in position against the inside

wall of the drum.

Further the drum may alternatively be hollow and made of an opaque material

eg. metal with holes formed therein in a desired pattern, to allow for the transmission

of light and the production of shadows as the drum is rotated. If required an acetate,

coloured or clear, with or without a coloured spiral can be included in this latter

embodiment.

The drum is preferably cylindrical in shape, though the transverse cross

section may alternatively have a desired polygonal shape. To explain, with a hollow

drum having a polygonal cross-section, both the internal and external transverse cross

section may have the same polygonal configuration, different polygonal

configurations, or only one cross section could be polygonal with the other

cylindrical, the latter two possibilities distorting light and enhancing the images

produced. With the drum arranged horizontally it is especially useful for producing a

flame effect in an electric fire. In such an instance the horizontal drum is located in

the front lower region of the fire with one or more lamps forming a light source and

providing preferably white light, located therebelow so that white light passes

through the drum onto the screen which is positioned primarily above the drum and

to the rear of the fire, in what could be termed an upper slim portion of the fire.

Preferably the horizontal drum is rotated so that the lower portion of the drum moves

towards the rearwardly positioned screen ie. clockwise when viewed from the left

hand end of the drum, to thus enhance realism by providing for simulated growing

flames .

In one embodiment the screen is preferably straight and virtually planar in its

upper region, and curved in a concave manner in its lower region. Further whilst the

surface of the screen may be polished and reflective, it is preferably covered with a

translucent plastics sheet to soften the ever moving image of flames produced on the

screen by the rotating drum. This translucent plastics sheet forms a semi-opaque

diffusing screen, and the flame effect on this screen is further enhanced if viewed

through a front tinted glass panel which is preferably screen printed with a variable

density of different relevant colours eg. yellow and red, this allowing varying colour

and light densities to be viewed.

Also a glass screen of varying thickness may, if desired, be placed between

the drum and the said screen, to enhance the flame image produced by the pattern and

spiral of the rotating drum, by further varying, softening and merging the images and thereby producing a more realistic effect.

In another embodiment the screen has a series of randomly arranged ie.

spaced apart, generally vertical ribs profiled therein ie. pressed therein, with the

major part of the screen being black and with a simulated reflective, preferably gold

coloured, flame region, in the form of a series of peaks or generally shaped flames.

Again the flame effect is enhanced by a front tinted glass panel which may be screen

printed in one colour or in different relevant colours eg. yellow and red, possibly of

varying density.

The present invention will now be further described, by way of example, with

reference to the accompanying drawings, in which:-

Fig. 1 is a perspective cutaway view of one embodiment of a fire

incorporating the present invention;

Fig. 2 is a plan view of the plastics sheet for use in the rotatable drum of the

present invention in planar condition;

Fig. 3 is a perspective cutaway view of a modified form of the present

invention;

Fig. 4 is an exploded view of a preferred form of rear screen used in Fig. 3;

and

Fig. 5 is a perspective cutaway view of another embodiment of a rotatable

drum for use in the present invention.

The embodiment of flame effect assembly constructed according to the

present invention and shown in Figs. 1 and 2 of the accompanying drawings, is shown as part of an electric fire 1 and comprises a horizontally arranged hollow drum

3 positioned in the lower frontal region of the fire, the drum 3 being rotatable at a

constant speed about the central longitudinal axis of the drum 3 by an electric motor

5. Beneath the drum 3 are located a light source in the form of two electric lamp

bulbs 7 each producing white light which is transmitted through the rotating drum 3

as discussed herebelow. The light transmitted by the drum 3 then passes in the

embodiment of Figs. 1 and 2, through a glass screen 9 of varying thickness which is

located above the drum 3, and onto a screen 11 which is viewed through a front tinted

glass panel 13. A glass fibre, GRP or plastics material, simulated coal or other fuel

bed moulding 15, is located over the front of the lower region of the fire to shield the

electric lamp bulbs 7 and the rotating drum 3 from view, the bulbs 7 illuminating the

simulated fuel bed 15 which is semi-opaque, from underneath so that the light

transmitted by the simulated fuel bed adds, together with the flame effect, to the

realism of the simulated solid fuel effect fire.

The hollow drum 3 is a hollow cylinder made of transparent plastics material,

with end caps 17 which are rotatably mounted in the fire 1, one end cap 17 being

freely rotatably mounted in a spring manner to facilitate withdrawal of the drum,

whilst the other end is connected to the electric motor 5. The electric motor 5, in use,

rotates the drum at a constant speed. Alternatively the drum speed can be

continuously variable. Further, other drive means may be substituted.

Means for producing random shadows or flame images in the form of a

rectangular transparent flexible plastics sheet 19 eg. acetate (see Fig. 2), painted or otherwise marked with a closed pattern network which defines a random arrangement

of randomly shaped apertures 21, is rolled into a cylinder and dimensioned to fit

inside the hollow drum 3, the sheet being biassed against the inside wall of the drum

by the inherent resilience of the normally flat flexible sheet. The paint or other

marking is opaque and the apertures 21 are also painted or printed with a transparent

hue of brown/beige colour. This hue varies in density diagonally across the

rectangular sheet as can be seen in Fig. 2, this hue softening the image produced by

the rotating drum 3 so that the simulated flame images tend to merge with each other

to varying degrees, as in a real fire, thereby enhancing realism.

In an alternative embodiment (not shown) the pattern or means for producing

randomly moving shadows can be painted or etched on the inside surface of the drum

3, or more preferably on the outside surface, the latter being of necessity if a solid

drum is alternatively used.

To further enhance realism a spiral, translucent strip 23 which is red in colour,

is located on the inside wall of the drum 3. In the embodiment illustrated in Figs. 1

and 2, this strip 23 is located between the flexible plastics sheet 19 and the inside

wall of the drum 3, with the sheet holding the strip 23 in the desired position. This

translucent red strip 23 allows red light to pass therethrough so that a moving red

image is achieved on the screen, contrasting with other yellowish flame images, and

enhancing realism. In an alternative embodiment where the drum 3 is hollow with

the pattern or means for producing shadows, painted or etched on the inside or

outside surface of the drum, the spiral, translucent strip 23 is located on the inside wall of the drum 3, and held there by the end caps 17, the natural resilience of the

spiral configured strip 23, and if necessary, an adhesive. Still further alternatives

provide for the pattern and/or strip 23 to be formed during manufacture, in the

material from which the drum is produced.

In order to produce growing flame images, the drum 3 is rotated by the

electric motor 5 so that the lower region of the horizontally arranged drum moves

towards the screen 11 ie. the drum rotates clockwise when viewed from the left hand

end.

The screen 11 consists of a reflector 25 and a front semi-opaque diffusing

screen 27 which softens and merges the moving images to enhance realism. The

screen 11 is virtually planar in its upper region but concave in its lower region, with

the varying thickness glass screen 9 being located in generally horizontal manner ie.

with its median plane arranged horizontally, under the concave lower portion so that

light passing through the drum 3, passes through the varying thickness glass screen

9 which also softens and merges the randomly moving sharp images produced by the

pattern on the drum 3, prior to impinging on the said screen 11.

The front tinted glass panel 13 referred to here above, is located in front of the

screen 11 and varying thickness glass screen 9, and is screen printed with a variable

density of different regions of colour eg. yellow and red, to allow varying colour and

light densities to be viewed, thus enhancing the flame effect achieved and the realism

of the flame effect produced.

In another embodiment of the present invention, illustrated in Figs. 3 and 4 of the accompanying drawings, the same reference numerals as used in the

embodiment of Figs. 1 and 2 are used to identify like features. To explain the main

differences between the respective embodiments, is the inclusion, in the embodiment

of Figs. 3 and 4, of a different concept of screen 11, and the omission of the variable

thickness glass plate 9.

The screen 11 in the embodiment of Fig. 3, comprises a major portion 29

which is dark in colour, preferably black, and of a matt-type finish, ie. of none or

limited reflectivity, with a series of reflective regions 31, preferably gold coloured,

of varying elongate, upwardly extending shapes, which, in use, enhance flame

simulation as produced by the rotating drum of the present invention. The reflective

regions 31 have upwardly extending ribs or ridges 33 formed at spaced apart

locations, which further enhance the required flame effect simulation. Such ribs can

also be provided in the major part 29.

To manufacture the major part 29 of the screen 11, and the said reflector

regions 31 , a sheet of metal is stamped out with the desired, generally rectangular,

outer periphery, and with the cutout desired shapes 32 for the reflective regions 31.

A sheet 35 of preferably gold coloured reflective material, pressed to form the desired

ribs, is then secured over the back of the major part 29 over the cutout shapes in the

major part 29, to thus form the desired random ribbed, reflective, growing flame

shapes to enhance the flame effect.

Further the major part 29 extends down behind the drum 3, so that its lower

edge 37 is level with the horizontal median plane of the drum 3. In this way light passing through the drum is collected by the screen 1 1 and passed forwards to the

front tinted glass panel (not shown in Fig. 3). Alternatively the lower edge 37 can

extend below the horizontal median plane of the drum 3, to the same effect.

The drum 3 of the present invention can alternatively be hollow and made of

an opaque material e.g. a metal, with holes 39 formed therein in a desired pattern, as

shown in Fig. 5 of the accompanying drawings, to thus allow for the transmission of

light and the production of shadows as the drum is rotated. If required an acetate,

coloured or clear, with or without a red spiral can be included.

Further, whilst reference is made hereabove to a hollow cylindrical drum 3,

or a solid drum, the transverse external cross section of the drum can be alternatively

polygonal, and the internal cross section of the drum when hollow, can be cylindrical

or polygonal, the selection of differing configurations, especially for internal and

external transverse cross sections providing for distortion of the images produced,

and for added enhancement of realism.

The present invention thus provides a simple, cost effective flame effect

assembly which has realism and which can, with advantage, be installed in an electric

fire of desired dimensions and aesthetic appeal.

Claims

1. A flame effect assembly comprising a drum having a longitudinal axis

about which the drum is arranged to, in use, be rotated, the drum being capable of at

least partially transmitting light therethrough from a light source, transverse to said

longitudinal axis, with means being incorporated in the drum for producing shadows

in the light which is transmitted through the drum generally transverse to said

longitudinal axis, and onto a screen.

2. An assembly as claimed in claim 1, in which the drum is arranged with

said longitudinal axis horizontal.

3. An assembly as claimed in claim 1 or claim 2, in which one end region of

the drum is connected to a drive motor for rotating the drum about the longitudinal

axis.

4. An assembly as claimed in claim 3, in which the other end region of the

drum is adapted to be spring mounted in a fire to facilitate withdrawal of the drum.

5. An assembly as claimed in claim 3 or 4, in which the drive motor is an

electric motor.

6. An assembly as claimed in any one of claims 3, 4 and 5, in which the drive

motor is arranged to rotate the drum at a constant speed.

7. An assembly as claimed in any one of claims 3, 4 and 5, in which the drive

motor is arranged to rotate the drum at a varying rotational speed.

8. An assembly as claimed in any one of claims 1 to 7, in which the

longitudinal axis is eccentrically positioned in the drum.

9. An assembly as claimed in any one of claims 1 to 8, in which the drum is

made of a transparent material, and the means for producing shadows is formed by

a predetermined random pattern carried by the drum.

10. An assembly as claimed in claim 9, in which the pattern comprises

apertures defined by a closed network.

11. An assembly as claimed in claim 9 or 10, in which the pattern is provided

by paint of any desired colour.

12. An assembly as claimed in claim 11, in which the pattern is totally

opaque or translucent.

13. An assembly as claimed in claim 10, in which the apertures have a

coloured hue.

14. An assembly as claimed in claim 13, in which the coloured hue varies in

density gradually over the drum.

15. An assembly as claimed in claim 9 or claim 10, in which the pattern is

painted or etched on the inside or outside surface of the drum.

16. An assembly as claimed in claim 9 or claim 10, in which the pattern is

formed on a flexible transparent sheet which is folded to a generally cylindrical form

which is located within and against the inside surface of the drum.

17. An assembly as claimed in any one of claims 9 to 16, in which a spiral

strip of coloured translucent material is provided on the drum.

18. An assembly as claimed in claim 17, in which the spiral strip is provided

by paint on the inside or outside of the drum.

19. An assembly as claimed in claim 17, in which the spiral strip is in the

form of a translucent coloured strip of plastics material located on the inside surface

of the drum.

20. An assembly as claimed in claim 19, in which the pattern is formed on

a flexible transparent sheet which is folded to a generally cylindrical form which is

located within and against the inside surface of the drum, with the spiral strip located

between the said transparent sheet and the inside surface of the drum.

21. An assembly as claimed in any one of claims 1 to 8, in which the drum

is hollow and made of an opaque material with holes formed therein in a desired

pattern, to allow the transmission of light and the production of shadows as the drum

is rotated.

22. An assembly as claimed in claim 21. In which a coloured or clear sheet

of flexible material is folded to a generally cylindrical form which is located within

the drum.

23. An assembly as claimed in claim 21 or 22, in which a coloured spiral of

translucent material is located within the drum.

24. An assembly as claimed in any one of the preceding claims, in which the

drum is cylindrical.

25. An assembly as claimed in any one of claims 1 to 23, in which the drum

has a polygonal external cross section, transverse to the said longitudinal axis.

26. An assembly as claimed in claim 25, in which the drum is hollow and has

a polygonal internal cross section, transverse to the said longitudinal axis.

27. An assembly as claimed in any one of the preceding claims, in which the

drum is arranged horizontally with a light source located below the drum so that the

light passes through the drum onto the screen which is positioned primarily above

and to the rear of the drum.

28. An assembly as claimed in claim 27, in which the drum is arranged to

rotate so that the lower portion of the drum moves towards the rearwardly positioned

screen.

29. An assembly as claimed in any one of the preceding claims, in which the

screen is straight and virtually planar in its upper region, and curved in a concave

manner in its lower region, with the surface of the screen covered with a translucent

plastics material.

30. An assembly as claimed in claim 29, in which a glass screen of varying

thickness is located between the drum and the screen.

31. An assembly as claimed in any one of claims 1 to 28, in which the screen

has a series of randomly arranged, generally vertical ribs, with the majority of the

screen being black with a simulated reflective flame region in the form of a series of

generally shaped flames.

32. An assembly as claimed in claim 31, in which the simulated flame

regions are gold coloured with at least some of the random ribs formed therein.

33. An assembly as claimed in claim 31 or claim 32, in which the screen is

formed in two parts, one part being black with cutout regions defining the simulated

flame regions, and the other part being a reflective sheet which is secured behind said one part so as to cover the cutout regions.