Note: Descriptions are shown in the official language in which they were submitted.
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Title: DIFFUSING SCREEN FOR PRODUCING THREE
DIMENSIONAL FLAME EFFECT
FIELD OF THE INVENTION
The present invention relates generally to simulated fireplaces
and, more particularly, to flame simulating assemblies for electric fireplaces
and the like.
BACKGROUND OF' THE INWENTION
Electric fireplaces are popular because they provide the visual
qualities of real fireplaces without the costs and complications associated
1 0 with venting of the combustion gases. An assembly for producing a
realistic
simulated flame for electric fireplaces is disclosed in U.S. Patent 4,965,707
(Butterfield). The Butterfif:ld assembly uses a system of billowing ribbons
and a diffusion screen for simulating flames. The simulated flames are
surprisingly realistiic, although the effect resembles a flame from a coal
fuel
1 5 source (which is popular in Europe), rather than a log fuel source (which
is
more popular in PJorth America). The flames for burning logs tend to be
more active and Extend higher above the fuel source. Also, the log flame
tends to be less red (and more yellow) in colour than the coal flame.
There is a need for an assembly for producing a simulated
2 0 flame that more rE:alistically resembles the flame from a burning log.
Also,
there is a need to improve the light intensity of the simulated flame to more
realistically resemble the intensity of real flames.
SUMMARY OF THE: INVENIfION
The presernt invention is directed to an improved flame
2 5 simulating assembly that produces a realistic appearing flame.
In one aspect, the invention provides a screen, for use in a
flame simulating assembly, comprising:
a translucent diffusing element having a thickness, said
diffusing element being composed of a material adapted to diffuse light
30 through said thickness; and
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a partially reflecting element disposed on a surface of said
diffusing element, said reflecting element having a partially reflecting
surface which faces away from said diffusing element;
wherein light passing through said diffusing element is visible
through said partially reflecting element.
In another aspect, the invention provides a screen, for use in a
flame simulating assemblly, comprising:
a translucent diffusing element that has first and second
opposing surfaces, at least one of said opposing surfaces being
1 0 substantially non-planar; and
a partially reflecting element disposed on one of said
opposing surfaces of said diffusing element, said reflecting element having
a partially reflecting surface which faces away from said diffusing element;
where light passing through said diffusing element is visible
1 5 through said partially reflecting element.
BRIEF DESCRIPTIC)N F THE DRAWINGS
For a better understanding of the present invention, and to
show more clearly how it may be carried into effect, reference will now be
made, by way of example, to the accompanying drawings. The drawings
2 0 show preferred embodiments of the present invention, in which:
Fig. 1 is a perspective view of an electric fireplace incorporating
a flame simulating assembly in accordance with the present invention;
Fig. 2 is a side view of the assembly of Fig. 1 showing
elements behind the side wall;
25 Fig. 3 is a front view of the assembly of Fig. 1 showing
elements below the top wall;
Fig. 4E is a top view of the assembly of Fig. 1 showing elements
behind the front w<~II;
Fig. ~~ is a front view of a flame effect element for the assembly
3 0 of Fig. 1;
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Fig. ti is a perspective view of the upper flicker element for the
assembly of Fig. 1, as viewed along direction arrow 6 in Fig. 3;
Fig. '7 is a partial plan view of a length of material defining a
plurality of radial strips for the upper flicker element of Fig. 1;
Fig. f3 is a pcsrspective view of the lower flicker element for the
assembly of Fig. 1, as viewed along direction arrow 8 in Fig. 3;
Fig. 9 is a top view of a fuel bed light assembly for the
assembly of Fig. 'I in accordance with a further embodiment of the present
invention;
1 0 Fig. '10 is a side view of a second embodiment of the flame
simulating assembly showing an alternative orientation of the flicker
elements;
Fig. '11 is a ifront view of a second embodiment of the vertical
screen showing the partiallly reflecting surface divided into regions;
1 5 Fig. '12 is an exploded detail view of a second embodiment of
the fuel bed;
Fig. 13 is a side view of a third embodiment of the flame
simulating assembly showing an alternative flame effect element;
Fig. 14 is a front view of the flame effect element for the
2 0 assembly of Fig. 13;
Fig. 15 is a perspective side view of a fourth embodiment of the
flame simulating assembly, showing an alternative flame effect element
and an alternative vertical screen;
Fig. '16 is a perspective side view of an alternative vertical
2 5 screen assembly for the assembly of Fig. 1 or Fig. 15;
Fig. 17 is a front view of the flame effect element for the
assembly of Fig. 15;
Fig. 18 is a front perspective view of an electric fireplace
incorporating a fire' wall simulating assembly;
3 0 Fig. 19 is a perspective side view of the fireplace of Fig. 18;
Fig. ~!0 is an enlarged perspective view of the inner surface of
the front wall of they assembly of Fig. 18; and
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Fig. 21 is a partial plan view of a length of material defining a
plurality of radial strips for an alternative embodiment of the upper flicker
element of Fig. 1 or Fig. 15.
DETAILED DESCRIIPTION ()F THE PREFERRED EMBODIMENT
A flame simulating assembly in accordance with the present
invention is shown generally at 10 in the figures. The assembly is
incorporated within an electric fireplace which is depicted generally at 12
with an electrical connection 13 for connecting to a power source (not
shown).
1 0 The electric fireplace 12 includes a housing 14 that defines a
simulated firebox having top, bottom, front, rear and side walls 16, 18, 20,
22
and 23, respectivE~ly. A portion of the front wall is defined by a transparent
front panel 24 that is removable to permit access to the contents of the
housing 14. A control unilr 21 is located above the top wall of the housing.
1 5 The control unit 2'I includes a heater unit 25, a thermostat 27 for
controlling
the heat output and a main power switch 29 for actuating the flame effect.
Referring to Fig. 2, a simulated fuel bed 26 is supported on a
platform 28 located at a lower front portion of the housing 14. The fuel bed
26 comprises a plastic shell that is vacuum formed and coloured to
2 0 resemble logs and embers for a log burning fire.
Portions of the shell are translucent to permit light from a light
source 30 located beneath the fuel bed 26 to shine through. For instance,
the shell may be formed from an orange translucent plastic. The top side of
the plastic shell may be painted in places to resemble the surface of logs.
2 5 The underside of the plastic shell may be painted black (or some other
opaque colour) and then sanded in portions where it is desired for light to
pass. For instance, the protruding points on the underside of the shell
(corresponding to indents in the top side) may be sanded to allow light
passage. These points would thus resemble the embers of a fire. Also, the
3 0 crotch area between simulated logs may be sanded (or left unpainted) to
resemble embers at the intersection of two logs.
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The light source 30 comprises three 60 watt light bulbs that are
supported in sockets 34 below i:he fuel bed 26. Alternatively, one or more
quartz
halogen lights may be utilized. The sockets 34 are supported by vertical arms
36
that are connected with fasteners 38 to the bottom wall of the housing 14. A
parabolic reflector 40 is located below the light source 30 at the lower front
end of
the housing 14 to direct light toward the rear of the housing 14. The
intensity of
the light can be varied with a dimmer switch 41 that is electrically connected
to the
light source 30 and located on the control unit 21.
In a further embodirnent of the invention as shown in Fig. 9, a fuel bed
light assembly 100 may be arranged beneath the underside of the fuel bed 26.
The fuel bed light assembly 100 includes a support element 102 that supports a
string of lights 104 beneath the fuel bed 26. The lights 104 are adapted to
flicker
at different times to give the impression of increases and decreases in heat
(as
depicted by differences of light intensity) in the embers of the fuel bed. It
has been
found that conventional Christmas lights are suitable for this purpose. It has
also
been found that a realistic ember effect may be generated by positioning four
regular light bulbs beneath the bed and randomly varying the intensity of the
lights
using a micro-processor (not shown).
Located immediately behind the fuel bed 26 is a vertical screen 42.
The screen 42 is transparent and has a partially reflecting surface 44 and a
diffusing surface 46. The screen 42 is seated in a groove 48 defined in a
lower
horizontal support member 5C). The lower horizontal support member 50 is
fastened to the side walls 23 of the housing 14 with fasteners 52. The screen
42
is supported on its sides with side frame members 54 that are fastened to the
side
walls 23 with fasteners 56. The screen structure is described in more detail
in U.S.
Patent 4,965,707.
The screen 42 is positioned immediately behind the fuel bed 26 so that
the fuel bed 26 will be reflectecl in the reflecting surface 44 to give the
illusion of
depth. As will be explained furtlher below, the image of simulated flames
appears
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to be emanating from between the fuel bed 26 and the reflection of the fuel
bed
26 in the screen. Also, simulated flames appear to be emanating from the
reflected image of the fuel bed 26. An upper light source 57 is located at the
top
front portion of the housing for illuminating the top of the simulated fuel
bed 26 and
enhancing the reflected image in the screen 42.
Referring more closely to the flame simulation assembly 10, the
assembly includes a flame effect element 58, a blower 60 and upper and lower
flicker elements 62 and 64.
As shown in Fig. 5, the flame effect element 58 is formed from a single
thin sheet of a light-weight, substantially opaque, material such as
polyester. The
element 58 extends across substantially the full width of the screen 42. A
plurality
of slits 66 are cut into the flame effect element 58 to permit passage of
light
through the flame effect element 58 as it billows under the influence of air
currents
from the blower 60. Longer sized slits 66 are located at the lower end of the
flame effect element 58 to simullate longer flames emanating from the fuel bed
26.
Smaller slits 66 are located at the upper end of the flame effect element 58
to
simulate the licks of flames that appear above the large main flames emanating
from the fuel bed 26. The slit;> 66 are arranged in a pattern that is
symmetrical
about a center axis 68 of the flame effect element 58 to give a balanced
appearance to the flame effect. The element 58 may be coated with a plastic
film
(such as polyurethane) to retard fraying about the edges of the slits.
Alternatively,
the flame effect element coulld comprise a plurality of discrete flame effect
elements 58 as disclosed in U.S. Patent 4,965,707.
The flame effect Element 58 is supported at its bottom end by
fasteners 70 that connect to thE; lower horizontal support member 50. The
flame
effect element 58 is supported at its upper end by fasteners 72 that connect
to an
upper horizontal support member 74. The upper horizontal support member is
connected by fasteners 76 to the side walls of the housing 14.
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The flame Effect element 58 is supported relatively loosely
between the hori~:ontal supports so that it will billow or ripple with the air
currents from the blower 60. The blower 60 is supported by a mounting
bracket 78 that is supported with fasteners 80 to the bottom wall of the
housing 14. An airflow control switch 83 is provided on the control unit 21 to
vary the blower airflow to a desired amount. The greater the airflow, the
more active the flame will appear. Alternatively, the flame effect element 58
may be moved mechanically to produce sufficient billowing or rippling to
give the flame effect.
1 0 In use, light is transmitted from the light source 30 through the
slits 66 of the fla~~me effect element 58 to the diffusing surface 46 of the
screen 42. The flame effect element 58 billows in the airflow from the blower
60 to vary the position and size of the slits 66. The resulting effect is for
the
transmitted light to resemlble flames licking from a fire. As will be
explained
1 5 further below, the transmitted light is at least partially coloured due to
its
reflecting from a c;olouredl reflecting surface 82 of a flicker element 62, 64
prior to passing through the slits 66.
The upper and lower flicker elements 62, 64 are located
rearwardly from the flame effect element 58 proximate to the rear wall of the
2 0 housing 14. As shown in Figs. 6 and 8, each flicker element comprises an
elongate rod 81 having a plurality of reflective strips 82 extending radially
outwardly therefrom. The rflicker elements 62, 64 preferably have a diameter
of about two to three inches. The strips 82 are formed from a length of
material having a 'width of approximately one and a half inches. A series of
2 5 transverse slits are cut along one elongate side of the length of the
material
83 to define each individual strip 82. The length of material 83 is then
wrapped about the rod 81 so that the strips 82 protrude radially about the
full
circumference of the rod 81. Alternatively, the strips 82 may be cut to
lengths
of around two to three inches and clamped at their centres by spiral wound
3 0 wires that form they rod 81. Alternatively, the reflective surfaces of the
flicker
elements could be' mirror~sd glass pieces arranged about the surface of a
cylinder.
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The rods 81 are supported at one end in corresponding
recesses 84 defined in a vertical support arm 86 that is connected by
fasteners 88 to the bottom wall of the housing 14. The rods 81 are
connected at their other end to corresponding rotors 90 for rotating each rod
81 about its axis. 'The rotors 90 are rotated by electric motors 91 as shown.
The rotors 90 are supported by a vertical support member 92 that is
connected with ifasteners 94 to the bottom wall of the housing 14.
Alternatively, the rotor 90 may be rotated by air currents from the blower 60
engaging corresponding fins on the rotors. Preferably, the rotors 90 rotate
1 0 the flicker elements 62, 64 in the direction indicated by arrow 93 in Fig.
2 so
that an appearance of upward motion is imparted on the reflected light
images. This simulates the appearance of upwardly moving gasses from a
fire. It is contemplated that other means for simulating the appearance of
upwardly moving gasses may be used. For instance, a light source (not
1 5 shown) may be contained within a moving, partially opaque, screen (not
shown) to producE~ the desired light effect. It is also contemplated that the
flicker elements 62, 64 or' the above described gas simulating means may
be used alone without thE: flame effect element 58. It has been found that
the use of the fli~;,ker elements 62, 64 alone produces a realistic effect
2 0 although not as realistic ass when used in combination with the flame
effect
element 58.
Referring to I=ig. 2, it may be seen that the lower flicker element
is positioned slightly below the horizontal level of the upper end of the fuel
bed 26. This facilitates tlhe appearance of upwardly moving gasses and
2 5 coloured flames E~manati~ng from near the surface of the fuel bed when
viewed by a person in front of the fireplace. Similarly, the upper flicker
element is positioned at a horizontal level above the fuel bed 26 to give the
appearance of upwardly moving gasses and coloured flames emanating a
distance above the fuel bed when viewed by a person in front of the
3 0 fireplace. In addition, the upper and lower flicker elements 62, 64
improve
the light intensity of the simulated flame and gasses.
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Referring more closely to Fig. 7, the strips 82 for the upper
flicker element 6:? are slhown. Each strip 82 is formed from a reflective
material such as PAYLART"". The strip 82 is preferably coloured with either a
blue or red tip 96 .and a silver body 98, although a fully silver body has
been
used successfully as well. A length of material 83 with red tipped strips 82
and a length of material 8.3 with blue tipped strips 82 may both be wrapped
about the rod 81. As shown in Fig. 6, a combination of blue and red tipped
strips 82 protrude radially from the rod 81 over the entire length of the
flicker
element 62. As a result, the upper flicker element 62 reflects white, red and
1 0 blue light that is subsequently transmitted through the flame effect
element
58.
The lower flicker element 64, as shown in Fig. 8, comprises a
dense arrangement of thin strips 82 that are formed from a reflective
material such as MYLART"". The strips 82 are either substantially gold in
1 5 colour, or substantially recl in colour. A combination of lengths of
material 83
with red strips 82 and gold strips 82 may be wrapped around the rod 81 to
produce an overall red and gold tinsel appearance. As a result, the lower
flicker element 64 reflects yellow and red light that is subsequently
transmitted through the flame effect element 58.
2 0 In use, the flicker elements 62, 64 are rotated by the rotors 90
so that the reflective surfaces of the strips 82 reflect colours through the
slits
66 of the billowing flame effect element 58 and produce the effect of
upwardly moving gasses. The colours reflected by the lower flicker element
64 resemble the colours of flames located near the surface of the fuel bed
2 5 26. The colours reflected by the upper flicker element 62 resemble the
colours of flames that are located further from the surface of the fuel bed
26.
The upper flicker element 62 has a less dense arrangement of strips 82 in
order to produce more random reflections that simulate a more active
flickering flame at a distance above the fuel bed 26. The more dense
3 0 arrangement of strips 82 in the lower flicker 64 produces relatively more
constant reflections that simulate the more constant flame activity adjacent
to the fuel bed 26.
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Referring to Fig. 10, an alternative orientation for the flicker
element 62, 64 is shown. The upper flicker element 62 is positioned slightly
below the horizontal level of the upper end of the fuel bed 26. The lower
flicker element 64 is positioned slightly above the horizontal level of the
lower end of the fuel bed 26. The lower flicker element 64 is positioned
slightly above the horizontal level of the lower end of the fuel bed 26.
Referring to Fig. 11, an improved vertical screen 42' is
depicted. The front of the screen includes a partially reflecting surface 44'
that is divided into a matte region 200, a transition region 202 and a
1 0 reflecting region 21)4. The reflecting region 204 is located at the lower
end of
the vertical screen 42' and is sufficiently sized for reflecting the fuel bed
26 to
produce the simulated effect. At the same time, the reflecting region 204 is
not overly sized so as to reflect unwanted images such as the floor covering
located immediatE~ly in front of the fireplace. For this reason, the vertical
1 5 screen 42' includes the matte region 200 at its middle and upper end. The
matte region 200 has a matte finish that does not reflect images while still
permitting visibility of the ;simulated flame image through the vertical
screen
42'. The transition region 202 comprises a gradual transition between the
non-reflective matte region 200 and the reflecting region 204.
2 0 Referring to Fig. 12, an improved fuel bed 26' is shown. The
fuel bed 26' includes a fiirst portion 206 composed of a ceramic material
and formed and coloured to simulate logs. The bed 26' also includes a
second portion 2'.08 connposed of a plastic material and formed and
coloured to simulate an ember bed. The ember bed 208 is preferably
2 5 translucent to permit the passage of light from the light source 30 or
fuel
bed light assembly 100 as described earlier. It has been found that a more
accurate simulation of logs 206 can be accomplished using ceramic
materials and flexible molds. The ember bed 208 can still be formed
realistically from pllastic using a vacuum forming method. The bed is formed
3 0 to receive the ceramic logo 206. The ceramic logs 206 are then glued to
the
ember bed 208 to 'form they fuel bed.
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Referring to Figs. 13 and 14, a third embodiment of the flame
simulating assembly 10 is depicted. For convenience, the same reference
numbers have been used to refer to the same elements. The third
embodiment does not include the blower 60 or the light-weight flame effect
element 58 which was adapted to billow in the airflow of the blower. Instead,
an improved flame effect element 58' is positioned behind and substantially
across the full width of they screen 42. The improved flame effect element 58'
is similar in appearance 1:o the flame effect element 58 depicted in Fig. 5.
However, the improved flaime effect element 58' is positioned preferably in a
1 0 generally vertical plane approximately three inches behind the screen 42
(and about 1/2 inch from the flicker elements 62, 64). The element 58' is
preferably formed of a more rigid material (e.g. plastic or thin steel) so
that it
will remain generally stationary in its vertical position. However, a light-
weight material such as polyester may be used instead with the element 58'
1 5 being stretched taut into a vertical position. Furthermore, it should be
understood that a vertical position for the element 58' is not critical, so
long
as light passage is possible as described below.
A plurality of slits 66' are cut into the flame effect element 58' to
permit passage of light from the light source 30 through the flame effect
2 0 element 58' to the screen 42. While the improved flame effect element 58'
remains relatively stationary, the flame simulation effect is nonetheless
observable due to the reflection of light from the flicker elements 62 and 64
as the light passes through the slits 66'.
The improved flame effect element 58' is sandwiched between
2 5 upper and lower support elements 210 and 212 to support the flame effect
element in a generally vertical position. The lower horizontal support
member 50 acts as one of the lower support elements. In addition, lower
horizontal support membE~r 50 acts as a horizontal opaque screen 214 to
block light from passing below the screen 42 and flame effect element 58'.
3 0 In this manner, substantially all of the light reaching the screen 42 has
been
reflected by flicker elements 62 and 64 and passes through slits 66' in the
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flame effect element 58'. The upper and lower support elements 210 and
212 are fastened to the side walls 23 of the housing 14 with fasteners 216.
Alternatively, the element 58' could be formed with a horizontal
living hinge at its lower End. The portion below the living hinge could be
connected to the screen 42 and act as the horizontal opaque screen 214.
The portion above the screen should be supported at least at its upper end
by the upper supf>ort element 210. The living hinge allows the element 58'
to be moved up or down as described below.
The flame effect element 58' is preferably movable upwardly or
1 0 downwardly relative to thE~ screen 42 in the direction of arrows 218. This
is
accomplished by ,~ heighlr adjustment mechanism shown generally at 220.
The mechanism 220 incluides a wire 222 connected to the top of the flame
effect element 58'. The wire 222 extends over a pin 224 and connects at its
other end to the end of ai height adjusting knob 226. The height adjusting
1 5 knob 226 protrudes from the front of the control unit 21 and is capable of
being moved inwardly and outwardly relative to the front face of the control
unit 21 in the direction of arrows 228. The height adjusting knob 226
includes a plurality of teeth 230 that engage the front face 232 of the
control
unit 21 to permit the knob 226 to be secured inwardly or outwardly relative to
2 0 the control unit 21 in one of a plurality of positions. It has been found
that, by
raising or lowering the flame effect element 58' by a predetermined amount,
the perceived intensity of the simulated flame (both the brightness and size
of the flame) effect can b~e increased or decreased. It is believed that this
change in intensity is due to the different sized slits 66' defined in the
flame
2 5 effect element 58' being more or less visible to an observer positioned in
front of the fireplace 12'.. It will be appreciated that alternative height
adjustment mechanisms rnay be chosen. For instance, the knob 226, may
be connected to i:he flame effect element 58' by a cam arrangement for
mechanically moving the Element 58' up or down.
30 The embodiment depicted in Fig. 13 further includes a
simulated fire screen 234 covering the front face 232 of the transparent front
panel 24. The simulated fire screen 234 is preferably a woven mesh such
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as is known for blocking sparks for conventional fireplaces. The woven
mesh fire screen 234 is :>upported at its top and bottom ends by pins 236
protruding from the front wall 20 of the housing 14. Alternatively, the
simulated fire screen 234. can be defined directly on the transparent front
panel 24 using a :;ilk screen process or the like. It has been found that the
simulated fire screen 234 reduces any glare or reflection that otherwise
might be visible on the transparent front panel 24.
Refeirring to Fig. 15, a further improved vertical screen 42" is
shown. The screen 42" is generally transparent and has a partially
1 0 reflecting surface 44" andl a diffusing region 46" through its thickness.
The
screen 42" is f<~bricate:d from a generally transparent but partially
translucent material preferably having a slightly clouded or milky
appearance through its thickness, such that light passing through the
screen 42" is partially transmitted and partially diffused. A satisfactory
1 5 material is a polystyrene 'which is given a slightly milky appearance by
the
addition of an amount o~f a powdered white pigment, such as titanium
dioxide. The particle size of the pigment material is preferably microscopic
so that a uniformly clouded or milky appearance is imparted to the diffusing
region 46". The amount of diffusion achieved by diffusing region 46" can be
2 0 controlled by the amount of pigment added to the plastic composition of
diffusing region 46". The amount of diffusion achieved by diffusing member
46" should be such that a three-dimensional flame appears through the
thickness of diffusing member 46", when viewed through partially reflecting
member 44".
2 5 By diffusing i:he projected light of the simulated flame gradually
through the thickness of tlhe screen 42", the improved screen 42" gives an
apparent thickness to the simulated flame, creating the illusion of a three
dimensional flame, Furthermore, the improved screen 42" does not rely on
a sandblasted or etched surface for its diffusing effect and therefore
3 0 simplifies construcaion of ;assembly 10.
Referring te~ Fig. 16, a further improved vertical screen
assembly 42"' is shown. The screen 42"' is composed of a reflecting
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member 44"' and a diffusing member 46"'. The reflecting member 44"' is
fabricated from a partially transparent, partially reflective material, such
as
semi-silvered glass. Diffuising member 46"' is fabricated from a translucent
material that partially transmits and partially diffuses light passing through
the diffusing member 46"'. Diffusing member 46"' may be made from a
transparent material similar to that used in screen 4, and given an etched or
sand-blasted diffusing surface, similar to diffusing surface 46.
Alternatively,
translucent materials, such as white polystyrene and polypropylene, have
also been found to be suitable for diffusing member 46"'. Where a
1 0 translucent material is used, the thickness of a particular material used
for
diffusing member 46"' is chosen to allow diffusing member to be self
supporting and yet remain translucent enough that a flame effect is
observable thereon through partially reflecting member 44"'. Diffusing
member 46"' does not necessarily embody the elements of diffusing
1 5 screen 46", described above.
Diffusing member 46"' is not planar but rather curved along its
length and width, the direction and amount of the curvature varying both
vertically and horizontally along diffusing member 46"'. Diffusing member
46"' may be conveniently formed by vacuum-forming a sheet of plastic to the
2 0 desired shape. The .curvature, in the vertical direction, of the lower
portion of diffusing member 46"' preferably follows the apparent location of
fuel bed 26 in reflectin~~ member 44"' (indicated at 26') to give the
appearance that 'the simulated flames projected thereon are emanating
from behind the rf~flection~ 26' of fuel bed 26. For example, if fuel bed 26
2 5 included simulated wood logs, the simulated flames projected on diffusing
member 46"' would appear to be emanating from behind the reflection 26'
of the simulated logs in fuel bed 26. The curvature of the lower portion
diffusing member 46"', in the horizontal direction along fuel bed 26,
preferably tracks the particular angle at which a simulated log appears to lay
30 in fuel bed 26 and follovvs the apparent location of the log in reflecting
member 44"' (indicated at 26'). At a horizontal position on fuel bed 26
where no simulated log appears, diffusing member 46"' is locally curved to
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be adjacent reflE~cting rnember 44"' to give the appearance that the
simulated flames projected thereon are emanating from the embers
between the simulated logs of fuel bed 26.
As diffusing member 46"' rises vertically away from fuel bed
26, it preferably then curves generally closer to reflecting member 44"' to
create the illusion that simulated flames projected thereon are licking over
the logs of fuel bed 26. The curvature of the upper portion of diffusing
member 46"' may be appropriately chosen to further simulate the turbulent
and random pattern of a rE~al flame.
1 0 The vertical screen assembly 42"' adds an additional three-
dimensional effect: to the simulated flame. When viewed through partially
reflecting member 44"', the simulated flame appears to emanate from
behind the simulated logs of fuel bed 26 and subsequently travel a three-
dimensional path as it appears to rise from fuel bed 26, which more
1 5 accurately simulates the appearance of a real wood fire.
Referring to Figs. 15 and 17, a fourth embodiment of flame
simulating assemk>ly 10 is depicted. For convenience the same reference
numbers have bE~en used to refer to the same elements. The fourth
embodiment does not include a blower 60 or a light-weight flame effect
2 0 element 58 adapi:ed to billow in the airflow of blower 60. Instead, an
improved and simpler flame effect element 58" is positioned behind and
substantially across the full width of the screen 42" (a screen 42, as shown
in Fig. 2, may equ~~lly be used), and in front of back wall 300. The improved
flame effect element 58" has a reflective surface 302 and generally has a
2 5 flame-like profile, as depicted in Fig. 17. Back wall 300 has a non-
reflective
surface. In a preferred embodiment, the element 58" is a reflective decal
applied to the surface of back wall 300. To simulate the colours of a natural
flame, flame effeca element 58" is preferably coloured with a bluish or
greenish base portion 304 and a silver body 306. The transition between
30 the blue portion 304 and the silver 306 is made gradually as the intensity
of
the blue colour in portion 304 is faded into silver portion 306.
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Referring again to Fig. 15, a single flicker element 62, rotating
in direction 93, is positioned below the fuel bed 26 and generally in front of
flame effect element 58". Adjacent and behind the flicker element 62 is
positioned the light sources 30. A light block 310 is provided to prevent
light
from light source 30 from reaching the flame effect element 58" directly.
Hence, substantially only light reflected from flicker element 62 reaches
flame effect elemE~nt 58" and is subsequently reflected to, and transmitted
through, screen 42". The apparent intensity of the simulated fire is
proportionate to the speE~d at which flicker element 62 turns. A variable
1 0 speed control (noi: shown) for flicker element 62 may be provided to allow
the user to alter the apparent intensity of the simulated fire.
The introduction of a fixed flame element 58" removes
previous problem:c of silk element 58 clinging to screen 42". Further, the
improved design removes the need for blower 60 and lower flicker 64,
1 5 making assembly 10 simpler to manufacture and maintain. Furthermore, by
repositioning the flicker element 62 beneath fuel bed 26, a more compact
flame simulating aasembly 10 may be achieved or, alternatively, fuel bed 26
may be moved further back, away from front panel 24, giving assembly 10
the look of a deeper, more realistic fireplace. Also, the repositioning of
2 0 flicker element 62 further simplifies the invention by removing the need
for a
light source 30 with flickering intensity.
The embodiment depicted in Fig. 15 may further include a
transparent light randomizing panel 312, positioned between fuel bed 26
and flicker element 62. The panel 312 is preferably made of glass or optical
2 5 grade plastic and has non-planar surfaces 314 and 316. The surfaces 314,
316 each have convex; and concave regions which smoothly and
contiguously blend into one another, resulting in a panel 312 having a varied
thickness. In use, panel 312 acts as a complex lens, with regions of varied
focal length, to light reflecaing towards fuel bed 26 from flicker element 62,
30 which is rotating in direction 93. The effect of the complex lens-like
characteristics of panel 312 is to intermittently reverse the direction of the
reflected light from flicker element 62 as it crosses fuel bed 26. The result
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is that the simulated coals of fuel bed 26 appear to flicker in a random
direction, and not only in the direction of rotation of flicker element 62.
Referring to Figs. 18, 19 and 20, a further improved flame
simulating assembly 10 with a simulated brick or rock fire wall 400 is
depicted. For convenience, the same reference numbers have been used
as previously to refer to the same elements. Referring to Fig. 19, simulated
fire wall patterns 402, 404 are applied to the inner surfaces of transparent
front panel 24 and each o~f side walls 23, respectively. Fire wall pattern 404
is applied by painting, or similar method, the pattern 404 on the inner
1 0 surface of each side wall 23. The pattern 402, as will be explained
further
below, is applied to the inner surface of transparent front panel 24
preferably
by applying, using a silk-screening method, a series of small coloured dots
in a random pattern. The dots are applied in such a manner that an
observer positionE:d in front of transparent front panel 24 will not readily
1 5 notice the dots applied to the inner surface of the panel 24 but will,
however,
notice the reflection of the dots in the reflecting surface 44. The effect
gives
the illusion of a vfire wall appearing behind the image of the simulated
flames emanating from the fuel bed 26. A light source 57 is provided
beneath top wall '16 to light the pattern 402 to strengthen its reflection in
2 0 surface 44. To create a more realistic lighting of patterns 402, 404,
light
source 57 may be made to flicker randomly to simulate lighting on the
simulated fire wall 400 by a real flame. The flicker in light source 57 could
be achieved by integrated circuit control (not shown) of the electricity
supplied to light source 57.
2 5 Referring to I=ig. 20, a preferred method of applying pattern 402
to the interior surface of front panel 24 is shown. First, a random pattern of
small dots 406 is applied to the inner surface of front panel 24. Although
random, the pattern of doia 406 has a constant dot density per square inch
across the entire inner surface of front panel 24. Dots 406 are preferably all
3 0 the same size. The dot density and a size of dots 406 are preferably
chosen
such that the presence of the dots 406 is not readily noticeable to an
observer and the only effect imparted to the glass by the presence of dots
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406 is a smoked ~or tinted appearance to transparent front panel 24. This
effect is best achieved if the dots 406 are black in colour. Preferably the
dots
406 are applied to the inner surface of panel 24 using a silk screening
process. Once the dots 406 have been applied, a set of coloured dots 408,
of slightly smaller diameter than dots 406, is applied on top of dots 406.
Dots 408 are of slightly smaller diameter than, and located concentrically
on, dots 406 to ensure that an observer positioned in front of assembly 10
will not notice the presence of dots 408 on the inner surface of transparent
panel 24. The dots 408 .are also preferably applied using a silk screening
1 0 process. Dots 408 preferably appear in two colours, the two colours being
the colour of the simulated brick and the colour of the simulated mortar
between the simulated Ibricks. The colour of a particular dot 408 is
preferably chosen such that an overall brick and mortar pattern is formed on
the inner surface of front panel 24.
1 5 In use, the presence of the dots 406 and 408 on the inner
surface of transparent front panel 24 is not readily noticed by an observer
positioned in front of flame simulating assembly 10, however, the reflection
of the coloured dots 406 in reflecting surface 44 is readily apparent to the
observer. The simulated fire wall 400 appears to the observer to be behind
2 0 fuel bed 26 at twice the distance of front panel 24 to the back of fuel
bed 26.
By locating dots 406 randomly across the inner surface of front panel 24, a
visible interference pattern is avoided. This interference pattern would
appear if the dots were regularly located on the inner surface of front panel
24, the interference pattE~rn being caused between the presence of dots
2 5 406, 408 on the inner surf;~ce of panel 24 and the reflection of dots 406,
408
on reflecting surface 44. Dots 406 are applied with a constant dot density
per square inch to ensure that the smoked or tinted appearance which dots
406 impart to front. panel :?4 is constant across front panel 24. The colours
chosen for pattern 402 are also the colours used for pattern 404 on side
3 0 walls 23. The patterns 402 and 404 are positioned on the inner surface of
front panel 24 and side walls 23, respectively, such that the apparent brick
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and mortar features of the two patterns intersect and mate in a realistic
fashion.
It will be app>arent that the simulated fire wall pattern 402 can
also be achieved using ali:ernate means. For example, a CLEAR FOCUST""
one-way vision display panel (not shown), as is described in U.S. Patent No.
5,525,177, may bE~ used. Simulated fire wall pattern 402 can be applied to
the display surface' of a CLEAR FOCUST"" panel which is, in turn, applied to
the inner surface of front panel 24, such that an observer positioned in front
of flame simulating assembly 10 cannot see pattern 402 directly but can
1 0 view the reflection of pattern 402 in reflecting surface 44. In another
embodiment, the transparent front panel 24 is replaced by a mesh front fire
screen 24 (not shown), and the simulated fire wall pattern 402 is applied,
with paint or similar means, to the inner surface of fire screen 24. If care
is
used to ensure that the pattern 402 is applied only to the interior surface of
1 5 fire screen 24, the pattern 402 will not be directly visible to an
observer
standing in front of flame simulating assembly 10. The observer will,
however, be able to view the reflection of pattern 402 on reflecting surface
44.
It is readily apparent that the apparatus to produce simulated
2 0 fire wall 400 could be used successfully with any fireplace having a front
panel 24 and reflecting surface 44. In particular, it will be apparent that
the
inclusion of a simulated fire wall 400 would greatly enhance the appearance
of a natural gas or propane fireplace. By using the disclosed apparatus to
create a simulated fire wall 400, the depth of a fireplace may be decreased
2 5 as a space-saving measuire, however, an observer will not notice that the
depth of the fireplace has been decreased.
Referring to Fig. 21, improved strips 82' for the upper flicker
element 62 are shown. Since the sharp, straight lines of previous flicker
element 62 gave sharp, straight reflections of light, which reduced the
3 0 realism of the flame simulation, each improved strip 82' is given a series
of
curvilinear cuts 82c. ThE: result is an improved upper flicker element 62
which reflects non-rectilinear patterns of light that are subsequently
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transmitted through the flame effect element 58. The non-linear nature of
the reflected light patteirns improves the realism of the flicker in the
simulated flame by causing the flickering patterns of reflected light to
appear
more random and therefore more natural.
It is to be understood that what has been described is a
preferred embodiment to the invention. The invention nonetheless is
susceptible to certain changes and alternative embodiments fully
comprehended by the spiirit of the invention as described above, and the
scope of the claima set oust below.
