Abstract:
A decorative torch produces a luminous flame and can be used on a patio or balcony as an aesthetically pleasing light and/or heat source. A filter received in a passage of a fuel tube minimizes acoustical noise generated by the flow of fuel from a pressurized fuel source. The fuel tube may omit any vents to enhance the luminous character of the flame and/or to reduce acoustical noise. Alternatively, a sleeve may be used to seal one or more vents. The sleeve may, or may not, be positionable on the fuel tube to adjust the number of vents sealed.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Technical Field  
         [0002]     This disclosure is generally related to decorative lighting, and more particularly to torches that bum a pressurized gas fuel to produce a luminous flame and can, for example, be used on a patio or balcony as an aesthetically pleasing source of light and/or heat.  
         [0003]     2. Description of the Related Art  
         [0004]     Decorative lighting is a fast growing market segment of the home and outdoor furnishings industry. Decorative lighting may be used indoors such as in the living room or dining room, or may be used outdoors such as on a patio or in a backyard, to provide a desired ambiance. In the respect, decorative lighting is typically employed to provide an aesthetic, soft, golden (i.e., luminous) flame. In addition to a pleasing light, decorative lighting in some forms may also provide a source of heat or warmth.  
         [0005]     Many forms of decorative lighting are known. Some forms of decorative lighting bum a solid fuel. For example, candles typically bum paraffin wax. Other forms of decorative lighting bum a liquid fuel. For example, Tiki style torches typically bum oil such as paraffin oil or citronella oil. Each of these suffer from drawbacks. For example, with respect to solid fuel decorative lighting, the flame tends to disappear from view as the fuel is consumed. An example of such is a candle, where as the wick at the center burns downward, the flame eventually disappears below a rim of the candle. Also for example, with respect to oil fuel decorative lighting, there is a potential for messy spills when filling a reservoir or when the reservoir is accidentally tipped over. The handling of messy oil is one of the greatest deterrents to the sales of such decorative lighting.  
         [0006]     While not typically associated with decorative lighting, it is also known to burn a pressurized gas to provide lighting. Such an approach is typically found in the camping industry. For example, the camping industry sells lanterns. Lanterns typically burn propane which is supplied under pressure from a fuel bottle to a mantle. Many examples of such are available from COLEMAN®. The provision of fuel in a spill-proof fuel bottle is a clean and easy approach to providing fuel. However, as anyone who has used one will recognize, lanterns are not intended as decorative lighting. Lanterns are designed to be efficient, producing a lot of light for a given amount of fuel, which tends to be rather harsh. Lanterns also produce a substantial amount of noise. As such, lanterns employing a pressurized fuel source do not serve the functions of decorative lighting, failing to produce the desired ambiance associated with a luminous flame produced with little or no noise.  
       SUMMARY OF THE INVENTION  
       [0007]     In one aspect, a device for producing a luminous flame from a pressurized fuel source comprises a burner including a plurality of apertures; a fuel tube, the fuel tube comprising a first end, a second end and a passage extending between the first and the second ends, the first end of the fuel tube connected to the burner, the passage of the fuel tube providing fluid communication between the second end thereof and the burner; a valve coupled to the second end of the fuel tube and selectively couplable to the pressurized fuel source, the valve selectively operable to control a flow of fuel from the pressurized fuel source to the burner via the fuel tube; and a filter closely received in the passage of the fuel tube to at least reduce an acoustic noise created when pressurized fuel is transferred from the pressurized fuel source to the burner via the valve and the fuel tube. The filter may be rolled or voluted, and may be made of fiberglass. A burner assembly and/or pressurized fuel source may be received in a shell, which may include a drain opening and/or a slot for providing external access to the valve. The device may also include a lid. The fuel tube may omit any vents, or a sleeve may be supplied to seal one or more vents. The sleeve may be positionable on the fuel tube to permit the selective sealing of any number of vents.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]     In the drawings, identical reference numbers identify similar elements or acts. The sizes and relative positions of elements in the drawings are not necessarily drawn to scale. For example, the shapes of various elements and angles are not drawn to scale, and some of these elements are arbitrarily enlarged and positioned to improve drawing legibility. Further, the particular shapes of the elements as drawn, are not intended to convey any information regarding the actual shape of the particular elements, and have been solely selected for ease of recognition in the drawings.  
         [0009]      FIG. 1  is a front, top isometric view of a decorative torch including a burner assembly recessed in a shell, the shell supported in a stand according to one illustrated embodiment.  
         [0010]      FIG. 2  is a side, exploded view of a pressurized fuel source and the burner assembly of the decorative torch of  FIG. 1 , showing a burner, fuel tube, filter, and valve.  
         [0011]      FIG. 3  is a top, plan view of the filter used in the fuel tube of  FIG. 2 .  
         [0012]      FIG. 4  is a side, elevational view of a fuel tube and a sleeve according to another illustrated embodiment, where the fuel tube includes one or more vents and the sleeve is positionable on the fuel tube to seal one or more of the vents.  
         [0013]      FIG. 5  is a side, elevational view of a shell and a lid of the decorative torch of  FIG. 1 , where the lid is removed from the shell.  
         [0014]      FIG. 6  is a front, top isometric view of the decorative torch of  FIG. 1  in operation. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]     In the following description, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the invention. However, one skilled in the art will understand that the invention may be practiced without these details. In other instances, well-known structures associated with valves, burners and/or pressurized gas containers or delivery systems are not shown or described in detail to avoid unnecessarily obscuring descriptions of the embodiments of the invention.  
         [0016]     Unless the context requires otherwise, throughout the specification and claims which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense, that is as “including, but not limited to.” In addition, the term “luminous,” and variations thereof as used herein, refers to a flame that produces visible light principally in at least the yellow or orange portions of visible light range the electromagnetic spectrum.  
         [0017]     The headings provided herein are for convenience only and do not interpret the scope or meaning of the claimed invention.  
         [0018]      FIG. 1  shows a decorative torch  10  supported in a stand  12  according to one illustrated embodiment. The stand  12  can take a variety of forms, for example a wrought iron decorative stand, a bracket extending from a patio or fireplace, and one or more wires extending from a support location.  
         [0019]     The decorative torch  10  may include a shell  14  and a burner assembly  16 . Where provided, the shell  14  is sized and dimensioned to receive and support the burner assembly  16  therein.  
         [0020]     The stand  12  and/or shell  14  may alternatively take the form of a fireplace, such as an outdoor fireplace.  
         [0021]      FIG. 2  shows a fuel container  20  and the components of the burner assembly  16 .  
         [0022]     The fuel container  20  can be a standard container, like the type used for camping or hiking as long as the container  20  is capable of holding white gas, kerosene, propane, butane, or another similar fuel. In one embodiment, the fuel container  20  is a COLEMAN® propane fuel bottle having a volume of 16.4 ounces, with the fuel held under pressure. Such fuel containers  20  may be made of a variety of materials, most often formed from a metal such as aluminum or a composite such as carbon graphite.  
         [0023]     The burner assembly  16  may comprise a valve  22 , a filter  24 , a fuel tube  26 , and a burner  28 .  
         [0024]     The valve  22  is an adjustable valve and is selectively couplable at one end to the fuel container  20 . In the illustrated embodiment, the valve  22  is manually adjustable with a handle and stem  23 . However, the valve  22  may be coupled to other adjustment means such as a solenoid, cams, a pawl and ratchet mechanism, or other similar device. In an alternate embodiment, the valve  22  is an electronically modulated valve that is automatically adjustable via a control system. In yet another embodiment, the valve  22  includes an electronic shut-off mechanism for rapidly stopping the flow of fuel and/or preventing flame propagation into the valve  22 .  
         [0025]     The fuel tube  26  has a first end  26 a connected to the burner  28  and a second end  26   b  coupled to the valve  22 . The fuel tube  26  forms a passage  26   c  ( FIG. 4 ) open at the first and second ends  26   a ,  26   b  for fluidly transporting fuel between the valve  22  and the burner  28 . In the embodiment illustrated in  FIG. 2 , the fuel tube  26  has no vents intermediate the first and second ends  26   a ,  26   b . This prevents air from mixing with the fuel in the fuel tube  26 . When using pressurized fuel, for example in lanterns or Bunsen burners, it is common to mix air into the fuel before the resulting fuel/air mixture reaches the burner  28  in order to achieve high efficiency. Such high efficiency is typically associate with a colorless, blue or green flame. A colorless, blue or green flame is considered to be less aesthetically appealing than a yellow or orange flame. The introduction of air may also contribute to production of acoustical noise, thus omitting the vent may reduce such noise.  
         [0026]     The filter  24  is closely received in passage  26 c of the fuel tube  26 . The filter  24  may minimize or eliminate the acoustical noise, typically experienced as a hissing sound, that is commonly associated with known pressurized gas devices (e.g., lanterns, Bunsen burners, camp stoves, etc.). Referring to  FIG. 3 , the filter  24  may take the form of a voluted (i.e., rolled) filter, and may be made from a variety of materials, for example fiberglass.  
         [0027]     Referring again to  FIG. 2 , the burner  28  includes a plurality of apertures  28   a  that allow the fuel to exit. The apertures  28   a  act as jets, ensuring that fuel flows from the burner assembly  16  at a sufficiently high rate and/or pressure such that the flame or combustion does not move into the burner assembly  16 . Thus, the burner  28  provides a surface on which the combustion or flame originates or is concentrated.  
         [0028]      FIG. 4  shows another embodiment of the fuel tube  26  having a one or more vents  30  located between the first and the second ends  26   a ,  26   b . A sleeve  32  slidably fits onto the fuel tube  26  and can be positioned with respect to the vents  30  to limit or prohibit air from entering the passage  26   c  and mixing with fuel. The sleeve  32  may be position to seal some, none or all of the of the vents  30 . In addition, the fuel tube  26  may include a stop  34  such as a flange or pin, to support the sleeve  32  when the sleeve  32  is in its fully downward position. The inner surface of the sleeve  32  may have grooves (not shown) at an upper end and at a lower end sized to receive respective O-rings (not shown) to provide a seal with the fuel tube  26 . The seal may prevent the escape of fuel vapors and/or prevent air from entering the passage  26   c  of the fuel tube  26  through the ends of the sleeve  32  during operation of the decorative torch  10 .  
         [0029]     As mentioned, the amount of air mixed into the fuel tube  26  during operation determines the luminosity of the flame of the decorative torch  10 . Closing the vents  30  at the base of the fuel tube  26  forces the burner  28  to use oxygen from the space adjacent to the burner  28 , which in turn produces a lower temperature, more visible or luminous flame. One reason for the luminous flame is that this type of combustion process creates residual carbon that is heated in the flame, and which produces the yellow or orange color of the luminous flame. In contrast, allowing the ambient air to mix with the fuel in the passage  26   c  of the fuel tube  26  produces a cleaner, hotter flame at the burner  28  which is typically considered highly desirable. Higher temperatures and efficient operation are often associated with a colorless, blue or green flames.  
         [0030]      FIG. 5  illustrates the shell  14  of the decorative torch  10 . The shell  14  comprises an upper region that is open to receive the burner assembly  16  therein and a lower region, which includes a drainage opening  36 . The drainage opening  36  is sized to permit water, moisture, or some other liquid substance that may otherwise accumulate in the shell  14  to adequately drain. In addition, the shell  14  can include a slot  38  to receive a portion of a valve  22 , for example, the handle and stem  23 . Hence, the slot  38  makes the valve handle accessible to a user to manually adjust the decorative torch  10 . Additionally, a lid  18  is sized to cover the shell  14 . The lid  18  helps to keep the burner assembly  16  dry and clean when the decorative torch  10  is not in use.  
         [0031]      FIG. 6  illustrates the decorative torch  10  in operation with a luminous flame  40 . The shell  14  holds the burner assembly  16  and is supported by a stand  12 .  
         [0032]     Although specific embodiments of and examples for the decorative torch are described herein for illustrative purposes, various equivalent modifications can be made without departing from the spirit and scope of the disclosure, as will be recognized by those skilled in the relevant art. The teachings can apply to any type of torch utilizing a variety of combustible gas fuel sources. Additionally, any method described above may include additional steps, omit some steps, and perform some steps in a different order than illustrated and/or otherwise described.  
         [0033]     The various embodiments described above can be combined to provide further embodiments. All of the above U.S. patents, patent applications and publications referred to in this specification are incorporated herein by reference. Aspects of the embodiments can be modified, if necessary, to employ devices, features, and concepts of the various patents, applications and publications to provide yet further embodiments.  
         [0034]     These and other changes can be made to in light of the above detailed description. In general, in the following claims, the terms used should not be construed to limit the invention to the specific embodiments disclosed in the specification and the claims, but should be construed to include all torches and decorative light sources that operate in accordance with the claims. Accordingly, the invention is not limited by the disclosure, but instead its scope is to be determined entirely by the following claims.