Diffusing screen with matte region

Information

  • Patent Grant
  • 6269567
  • Patent Number
    6,269,567
  • Date Filed
    Friday, March 3, 2000
    24 years ago
  • Date Issued
    Tuesday, August 7, 2001
    23 years ago
Abstract
A simulated fireplace assembly is provided having a simulated fuel bed and a screen for transmitting an image of a flame. The simulated fuel bed is located adjacent to the screen. The screen has a first region that is sufficiently reflective to reflect the fuel bed and a second region that is sufficiently non-reflective to avoid reflection of ambient subject matter that is not associated with the fireplace assembly.
Description




FIELD OF THE INVENTION




The present invention relates to flame simulating assemblies for electric fireplaces and the like.




BACKGROUND OF THE INVENTION




Electric fireplaces are popular because they provide the visual qualities of real fireplaces without the costs and complications associated with venting of the combustion gases. An assembly for producing a realistic simulated flame for electric fireplaces is disclosed in U.S. Pat. No. 4,965,707 (Butterfield). Butterfield includes a diffusing screen having a reflective surface for reflecting a simulated fuel source to give the illusion of flames emanating from within the real and reflected images of the fuel source.




A problem with this arrangement of screen is that unwanted images such as the floor or items of furniture or a person standing in front of the electric fireplace are also reflected in the screen. This has the effect of reducing the illusion provided by the fireplace.




SUMMARY OF THE INVENTION




In one aspect, the present invention is directed to a generally transparent screen for use in a flame simulating assembly comprising:




a body having a partially reflecting surface and a diffusing surface, said surfaces being opposed;




a matte region located at one portion of said partially reflecting surface, said matte region having a matte finish that is substantially non-reflective; and




a reflective region located at another portion of said partially reflective surface, said reflective region having a reflective finish.




In another aspect the invention provides a simulated fireplace assembly comprising:




a simulated fuel bed; and




a screen adjacent to said simulated fuel bed for transmitting an image of a flickering flame, said screen having a first region that is sufficiently reflective to reflect said fuel bed and a second region that is sufficiently non-reflective to avoid reflection of ambient subject matter that is not associated with said fireplace assembly.











BRIEF DESCRIPTION OF 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 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;





FIG. 3

is a front view of the assembly of

FIG. 1

showing elements below the top wall;





FIG. 4

is a top view of the assembly of

FIG. 1

showing elements behind the front wall;





FIG. 5

is a front view of a flame effect element for the assembly of

FIG. 1

;





FIG. 6

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. 8

is a perspective 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. 1

in accordance with a further embodiment of the present invention;





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 front view of a second embodiment of the vertical screen showing the partially reflecting surface divided into regions;





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; and





FIG. 14

is a front view of the flame effect element for the assembly of FIG.


13


.











DETAILED DESCRIPTION OF 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).




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


, respectively. 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 unit


21


is located above the top wall of the housing. The control unit


21


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 colored to 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. The underside of the plastic shell may be painted black (or some other opaque color) 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 crotch area between simulated logs may be sanded (or left unpainted) to resemble embers at the intersection of two logs.




The light source


30


comprises three 60 watt light bulbs that are supported in sockets


34


below the 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 embodiment 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


50


. 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. Pat. No. 4,965,707 which is incorporated herein by reference.




The screen


42


is positioned immediately behind the fuel bed


26


so that the fuel bed


26


will be reflected in the reflecting surface


44


to give the illusion of depth. As will be explained further below, the image of simulated flames appears 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 simulate 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 slits


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 could comprise a plurality of discrete flame effect elements


58


as disclosed in U.S. Pat. No. 4,965,707 that is incorporated herein by reference.




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


.




The flame effect element


58


is supported relatively loosely between the horizontal 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.




In use, light is transmitted from the light source


30


through the slits


66


of the flame 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 resemble flames licking from a fire. As will be explained further below, the transmitted light is at least partially colored due to its reflecting from a colored 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 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 flicker 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 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 centers by spiral wound wires that form the rod


81


. Alternatively, the reflective surfaces of the flicker elements could be mirrored glass pieces arranged about the surface of a cylinder.




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 fasteners


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 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 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 flicker elements


62


,


64


alone produces a realistic effect although not as realistic as when used in combination with the flame effect element


58


.




Referring to

FIG. 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 the appearance of upwardly moving gasses and colored flames emanating 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 colored flames emanating a distance above the fuel bed when viewed by a person in front of the fireplace. In addition, the upper and lower flicker elements


62


,


64


improve the light intensity of the simulated flame and gasses.




Referring more closely to

FIG. 7

, the strips


82


for the upper flicker element


62


are shown. Each strip


82


is formed from a reflective material such as MYLAR™. The strip


82


is preferably colored 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


83


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 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 MYLAR™. The strips


82


are either substantially gold in color, or substantially red in color. 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


.




In use, the flicker elements


62


,


64


are rotated by the rotors


90


so that the reflective surfaces of the strips


82


reflect colors through the slits


66


of the billowing flame effect element


58


and produce the effect of upwardly moving gasses. The colors reflected by the lower flicker element


64


resemble the colors of flames located near the surface of the fuel bed


26


. The colors reflected by the upper flicker element


62


resemble the colors 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 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


.




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 reflecting region


204


. 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 immediately in front of the fireplace. For this reason, the vertical 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


.




Referring to

FIG. 12

, an improved fuel bed


26


′ is shown. The fuel bed


26


′ includes a first portion


206


composed of a ceramic material and formed and colored to simulate logs. The bed


26


′ also includes a second portion


208


composed of a plastic material and formed and colored to simulate an ember bed. The ember bed


208


is preferably 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 plastic using a vacuum forming method. The bed is formed to receive the ceramic logs


206


. The ceramic logs


206


are then glued to the ember bed


208


to form the fuel bed.




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 the screen


42


. The improved flame effect element


58


′ is similar in appearance to the flame effect element


58


depicted in FIG.


5


. However, the improved flame effect element


58


′ is positioned preferably in a generally vertical plane approximately three inches behind the screen


42


(and about ½ 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


′ 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 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 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 member


50


acts as a horizontal opaque screen


214


to block light from passing below the screen


42


and flame effect element


58


′. 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 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 support 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 downwardly relative to the screen


42


in the direction of arrows


218


. This is accomplished by a height adjustment mechanism shown generally at


220


. The mechanism


220


includes 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 a height adjusting knob


226


. The height adjusting 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 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 be increased or decreased. It is believed that this change in intensity is due to the different sized slits


66


′ defined in the flame 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 may be chosen. For instance, the knob


226


, may be connected to the flame effect element


58


′ by a cam arrangement for mechanically moving the element


58


′ up or down.




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 as is known for blocking sparks for conventional fireplaces. The woven mesh fire screen


234


is supported 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 silk 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


.




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 spirit of the invention as described above, and the scope of the claims set out below.



Claims
  • 1. A simulated fireplace assembly having:a simulated fuel bed; a light source; and a screen having a partially reflective front surface disposed behind the simulated fuel bed for reflecting and transmitting light, and a back surface disposed behind the partially reflective front surface for transmitting light, the partially reflective front surface having a substantially non-reflective matte region, the non-reflective matte region being disposed distal from the simulated fuel bed, and the portion of the front surface not covered by the non-reflective matte region being a reflective region, such that the simulated fuel bed is substantially the only object reflected in the front surface, wherein light from the light source is transmitted through the front surface such that an image of flames appears through the front surface.
  • 2. A simulated fireplace assembly as defined in claim 1 wherein the front surface further includes a transition region which is partially reflective and partially non-reflective, the transition region being disposed between the non-reflective matte region and the reflective region.
  • 3. A simulated fireplace assembly having:a simulated fuel bed; a light source; a screen having a partially reflective front surface disposed behind the simulated fuel bed for reflecting and transmitting light, and a diffusing back surface disposed behind the partially reflective front surface for diffusing and transmitting light; a flicker element positioned in a path of light transmitted from the light source to the diffusing back surface; and the partially reflective front surface having a substantially non-reflective matte region, the non-reflective matte region being disposed distal from the simulated fuel bed, and the portion of the front surface not covered by the non-reflective matte region being a reflective region, such that the simulated fuel bed is substantially the only object reflected in the front surface, wherein light from the light source is transmitted through the front surface such that an image of flames appears through the front surface.
  • 4. A simulated fireplace assembly as defined in claim 3 wherein the front surface further includes a transition region which is partially reflective and partially non-reflective, the transition region being disposed between the non-reflective matte region and the reflective region.
  • 5. A simulated fireplace assembly having:a simulated fuel bed; a light source; a screen having a partially reflective front surface disposed behind the simulated fuel bed for reflecting and transmitting light, and a diffusing back surface disposed behind the partially reflective front surface for diffusing and transmitting light; a flicker element positioned in a path of light transmitted from the light source to the diffusing back surface; a flame effect element positioned in the path of light, for configuring light; and the partially reflective front surface having a substantially non-reflective matte region, the non-reflective matte region being disposed distal from the simulated fuel bed, and the portion of the front surface not covered by the non-reflective matte region being a reflective region, such that the simulated fuel bed is substantially the only object reflected in the front surface, wherein light from the light source is transmitted through the front surface such that an image of flames appears through the front surface.
  • 6. A simulated fireplace assembly as defined in claim 5 wherein the front surface further includes a transition region which is partially reflective and partially non-reflective, the transition region being disposed between the non-reflective matte region and the reflective region.
Parent Case Info

This is a divisional application based on application Ser. No. 08/801,469, filed Feb. 18, 1997, now U.S. Pat. No. 6,047,489, which was a continuation-in-part application of application Ser. No. 08/649,510, filed May 17, 1996, now U.S. Pat. No. 5,642,580.

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Entry
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Continuation in Parts (1)
Number Date Country
Parent 08/649510 May 1996 US
Child 08/801469 US