Background of the Invention
1. Field of the Inventions
This invention relates to units that may be used in place of traditional burning of wood logs in a fireplace and more particularly to a unit that may burn a non-toxic fuel and produce an illusion of burning logs at the same time.
2. Prior Art
Units that simulate burning in a fireplace have been known and in use for many years.
One early fireplace simulation unit is set forth in U.S. Pat. No. 1,867,740. This unit includes a grate covered with a light diffusing material. In a compartment below the grate is a light source provided with a flicker fan. When energized, these produce an illusion of flickering flames in the light diffusing material. Additionally, the unit has an electric heating element for warming ambient air in the room in which the unit is placed.
A more recent fireplace simulation unit is disclosed in U.S. Pat. No. 3,742,189. This unit includes a set of partial artificial logs spaced apart for placement of wire brackets. These brackets hold ornamental strips having flame-like shapes. Aligning with these strips within each of the lower logs is a light bulb. In a housing assembly positioned below the logs is a fan unit and an electric heating element. When the unit is in use, the fan blows air over the heating element to circulate warmed air and over the ornamental strips causing a rippling movement of such. Light from the bulbs in turn reflects from the rippling strips to produce an illusion of flame between the logs.
A still more recent fireplace simulation unit is set out in U.S. Pat. No. 4,573,905 issued to the same inventor as the herein disclosed invention. This recent unit includes a fuel cell for cans of gel alcohol that may be burned safely in a room without ventilation. This cell is hidden from view by a set of artificial logs. The fuel cell is supported by a grate which in turn is carried by a base. Below the grate in a top surface of the base is an opening covered by an amber colored glass piece. Small pieces of rock in turn cover the glass piece. In the base below the glass piece is a light source. During use alcohol in the fuel cell cans may be ignited to produce heat. Additionally, the light may be energized to illuminate upward and produce an illusion that the rock pieces are glowing coals.
Summary of the Invention
A unit of this invention that produces heat and simulated burning of wood logs includes an enclosure that may form part of a nonvented fireplace or may be readily placed on a hearth of a traditional fireplace, for example. In the enclosure is a light source which is positioned next to a reflection wheel rotatable by a geared motor. This wheel comprises a series of reflective strips which are attached to and extend outward from a twisted wire shaft. These strips are positioned along a length of the shaft and spaced radially about the shaft. Below the reflection wheel on a bottom of the enclosure is a reflective plate which aligns with an opening in a top panel of the enclosure. This opening is covered by an amber-red colored lens which in turn is covered with artificial ash-like material.
The unit further includes a grate that sits on the enclosure top panel. The grate is defined by a set of spaced apart bars having upturned front segments to hold a first of a set artificial log portions. Behind this first log portion is a fuel cell to hold cans containing a gel alcohol fuel. The fuel cell is further screened from view by a second log portion positioned in front of the cell and a third log portion attached to a slidable lid of the fuel cell.
When the unit is to be used, the fuel cell lid is slid rearward to uncover the cans. The gel alcohol then may be ignited to produce heat and warm air in the room in which the unit is located. Additionally, the light source and geared motor may be energized to emit light and slowly rotate the reflection wheel. The emitted light strikes the reflective plate and the reflective strips of the wheel to produce a series of light patterns of varying intensity. These patterns interact and then shine upward and pass through the lens piece. The now amber-red colored patterns of light reflect from the ash on the lens piece, bottom edges of the first and second log portions, and interior walls of the fireplace. As reflected, these patterns of light produce an illusion that the logs are burning and as such are emitting a fiery glow.
This inventive unit to produce heat and simulated burning of wood logs in a fireplace provides several improvements over other like units known or in use.
A first improvement is a truly authentic illusion of the burning logs. The patterns of light that produce the burning illusion vary in both intensity and location. As one portion of a log is subjected to a gradually increasing intensity of light, the light intensity on an adjacent portion is gradually decreasing. These changes of intensity also affect the color of the illusionary burning. Authenticity is further enhanced by subjecting the entire length of a log portion to these changing patterns of amber-red light. Thus, an entire log appears to be burning. This burning effect also is transmitted to and then reflects from the side and rear walls of the fireplace. These dynamic patterns of light, varying in location, intensity and color, are a result of a reflective interaction between the light source, the reflective plate and the slowly rotating reflective strips of the wheel.
A second improvement is that the unit allows a user to produce heat, a burning illusion, or both. The heating function and the burning function are mutually exclusive. It should be appreciated that a pure alcohol gel burns with a colorless, nearly invisible flame. However, an additive may be introduced into the gel to produce visible flaming. Thus, the unit may produce the illusion of burning and blazing, heat producing flame.
Description of the Drawings
FIG. 1 is perspective view of a simulation burning unit of this invention forming part of an imitation fireplace cabinet.
FIG. 2 is a side elevation cross sectional view of the unit of FIG. 1.
FIG. 3 is a further cross sectional view as seen generally along the line 3--3 in FIG. 2.
FIG. 4 is a view of a selective portion of a reflection wheel of the unit as seen along the line 4--4 in FIG. 2.
FIG. 5 is a plan view of a portion of a material blank used to form reflective strips comprising a part of the reflection wheel of the unit.
Description of the Preferred Embodiment
A unit of this invention to produce simulated burning and heat in a fireplace is shown generally in FIGS. 1 and 2 and designated 10. In FIG. 1 the unit 10 is shown forming part of a hearth 12 of a fireplace 14. In this case the fireplace 14 is a nonvented display cabinet as set out typically in U.S. Pat. Nos. Des. 292,152 and 292,251. The unit 10 alternatively may be placed on the hearth of a traditional fireplace of masonry construction forming part of a residence, for example.
As seen in FIGS. 2 and 3, the unit 10 includes a base enclosure 16 defined by a bottom 18, sidewalls 20, a front wall 22, a rear wall 24 and a top panel 26. Extending upward from the enclosure bottom 18 is a bracket 28 to carry a socket 30 for an elongated light bulb 32. Positioned inward from the bracket 28 on the bottom 18 is a reflective plate 34. A pair of spaced apart angle brackets 36 are fastened to the bottom 18 on each side of the plate 34.
A first end 38 of a shaft 40 of a reflection wheel 42 is carried by an upright portion 44 of one angle bracket 36. An opposite end 46 of the shaft 40 is operatively connected by a coupling 48 to an output shaft 50 of geared motor 52. This motor 52 is attached to the upright portion 44 of the other angle bracket 36.
Both the light bulb 32 and the motor 52 are connected to a source of electricity by circuit wires 54. Note that the bulb 32 and the wheel shaft 40 are horizontally aligned and that the bulb 32 is positioned below the shaft 40 of the reflection wheel 42.
As best understood by viewing FIGS. 2-5, the reflection wheel 42 comprises a series of radially spaced apart reflective strips 56. These strips 56 in turn are formed by two sets of spaced apart slits 58,60 which extend inward from side edges 62,64 of a sheet of a reflective plastic material 66, see FIG. 5. Each set of slits 58,60 terminates short of a narrow, center area 68 of the sheet 66. Note the set of slits 58 is longitudinally offset from the other slit set 60.
The shaft 40 of the wheel 42 is formed from two wires 70 which first are placed one each on respective sides of the center area 68 of the sheet 66. As seen in FIG. 4, the wires 70 then are twisted so that individual reflective strips 56 project radially outward in a spiral-like pattern from the shaft 40. As seen in FIG. 2, the wires 70 of the shaft 42 have been twisted to a degree that adjacent reflective strips 56 are spaced at approximately 120 degree increments about the shaft 40. This twisting also produces a small degree of pitch in the position of the reflective strips 56, like vanes of a fan. If the shaft wire 70 were twisted more tightly, the radial increment between strips 56 would decrease and the degree of pitch increase. Note further that the reflective strips 56 extend longitudinally nearly an entire length of the shaft 40. The shaft 40 of the reflection wheel 42 is positioned over a front portion 72 of the plate 34.
In the top panel 26 of the base enclosure 16 of the unit 10 is a rectangular shaped opening 74 covered by an amber-red colored lens piece 76 made of glass or other transparent material. This opening 74 is approximately twice the size of the reflective plate 34 and is vertically aligned therewith. Positioned over this top panel opening 74 and lens piece 76 is a front portion 78 of a grate 80.
This grate 80 has two sets of leg pairs 82 that rest on the enclosure top panel 26 and that are positioned respectively on each side of the opening 74. The grate 80 is further defined by a series of spaced apart bars 84 formed with upturned front end portions 86. Positioned on the grate bars 84 inward from the upturned end portions 86 is a fuel cell 88. The cell 88 includes a fire box portion 90 to hold cans of gel alcohol fuel (not shown). Spaced apart sidewalls 92 of the fire box portion 90 extend to a rear of the fire box portion 90. Top edges 94 of these sidewalls 92 in turn form a guide for a slidable lid 96. This lid 96 may be placed on the fuel cell fire box portion 90 to form a cover or slid to the rear to expose the fuel cans therein.
The fuel cell 88 is hidden from view by a set of three decorative log portions 98, 100 and 102. These log portions 98-102 may be made from a noncombustible, ceramic material and have a semicircular cross sectional shape. An outer radiused surface side 104 of each log 98-102 has a wood log appearance. As seen in FIGS. 1 and 2, the first log 98 is positioned against the grate bar upturned end portions 86. The second log 100 is positioned immediately in front of the fuel cell 88 and is carried by a pair of brackets 106 attached respectively to the sidewalls 92 of the fuel cell fire box 90. As positioned, the second log 100 is located above the first log 98. Along a bottom edge 108 of each log 98,100 is a reflective strip 110 of clear plastic material. Note that these strips 110 also have a radiused shape. The third log portion 102 is attached to the fire box lid 96. To complete the fireplace appearance the base enclosure top panel 26 and lens piece 76 may be partially covered with an ash-like material 112, see FIG. 1.
During use the unit 10 may produce heat, simulated burning or both. As discussed briefly above, the unit 10 may be placed on the hearth of a conventional fireplace or form part of the hearth 12 of the fireplace cabinet 14. To produce only heat, the lid 96 of the fire box 90 is slid to the rear to uncover the cans of alcohol gel fuel contained therein. This fuel then may be ignited with a match, for example. Note that burning alcohol produces only water vapor and carbon dioxide, each being nontoxic. Therefore, as heat is being generated, the fireplace cabinet 14 need not be vented to the out-of-doors. To extinguish the burning of the alcohol in the fuel cell 88, the lid 96 is slid forward to cover the fire box 90. When oxygen in the fire box 90 is sufficiently depleted, combustion terminates.
When the unit 10 is to produce simulated burning, a switch (not shown) connecting with the circuit wires 54 may be placed in an "ON" position to energize the light bulb 32 and the geared motor 52. Light from the bulb 32 strikes the reflective plate 34, the reflective strips 56 of the reflection wheel 42 which slowly rotates at about 30 rpm and shines upward through the lens piece 76. As light strikes the reflective plate 34 and the reflective strips 56, it reflects in a compound, interacting manner to produce upward illumination comprising series of light patterns. The intensity of the light in each pattern changes continuously. This change of intensity is a result of a continuous changing of the angle of incidence of light striking and then reflecting from the rotating reflective strips 56 of the reflection wheel 42.
As these dynamic patterns of light pass through the lens 76, color of the light changes from white to an amber-red. It should be understood the light bulb 32 could be so colored in which case the lens piece 76 would be clear or slightly opaque. Note further that the changes of intensity of the light patterns discussed above also produces variations in the color of the light. These emitted colored light patterns then strike the reflective strips 110 of the logs 98,110 and sidewalls 114 and a rear wall 116 defining an interior space 118 of the fireplace cabinet 14.
Light reflects from all of these surfaces 110, 114 and 116 to be viewed by persons in the room in which the fireplace cabinet 14 and included unit 10 are located. As viewed, the logs 98,100 are perceived as being on fire as the bottom edges 108 of the logs 98,100 and the ash 112 are seen to have a fiery glow. As occurs when burning a log of natural wood, portions of the logs 98,100 appear to burn more intensely from time to time. Also, as occurs when burning natural wood logs in a conventional fireplace, the interior surfaces 114, 116 are illuminated by this illusionary burning. Placement of the switch in its "OFF" position de-energizes the light bulb 32 and motor 52 and terminates the illusion.
While an embodiment, uses and advantages of this invention have been shown and described, it should be understood that this invention is limited only by the scope of the claims. Those skilled in the art will appreciate that various modifications or changes may be made without departing from the scope and spirit of the invention, and these modifications or changes may result in further uses and advantages.