Patent Publication Number: US-2007111149-A1

Title: Lamp With Means For Controlling Air And Fuel Near The Flame

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application claims priority to co-pending U.S. provisional application entitled “Cylindrical Wick Lamp,” which has Ser. No. 60/836,836 and was filed Aug. 10, 2006, and which is entirely incorporated herein by reference.  
      This application is a continuation-in-part of co-pending U.S. utility application entitled “Apparatus for Controlling a Flame,” which has Ser. No. 10/890,342 and was filed Jul. 13, 2004, and which is entirely incorporated herein by reference. 
    
    
     BACKGROUND  
      A lamp is an apparatus that produces light. One type of lamp includes a wick and a fuel source. The wick communicates fuel from the fuel source to an end of the wick that is exposed to the atmosphere. Igniting the exposed end of the wick initiates the chemical process of combustion, producing a flame. In turn, the flame produces light through the process of incandescence.  
      During combustion, the fuel reacts with oxygen in the air to produce the flame. In cases in which the combustion of the fuel is incomplete, disadvantages may result. For example, unburned fuel produces smoke particles that irritates the eyes or fuel vapors that smell foul. Some smoke particles contain toxins such as acetone and benzene, which are by-products of the incomplete combustion process. Incomplete combustion may also create a flame that is not uniform in color and luminosity. For example, the flame may have a bright area at a top of the flame and a dark area at a base of the flame.  
      Although complete combustion is virtually impossible, imperfection in the combustion process can be reduced by controlling the air and fuel in the vicinity of the flame. For example, some existing lamps provide a shield around the flame to protect the flame from air drafts, which cause fuel particles to escape from the vicinity of the flame before being burned. However, such shields also reduce the volume of fresh air that reaches the flame, and as a result the fresh air supply may be inadequate to combust the fuel that is present in the flame vicinity. From the above description, a need exists in the industry for a lamp that solves these and other problems.  
     SUMMARY  
      In one embodiment, a lamp includes a fuel reservoir, a hollow wick, and an air channel. The fuel reservoir is configured to hold a volume of fuel. The hollow wick is configured to wick the fuel from the fuel reservoir to the atmosphere such that a flame is produced when the wick is ignited. The air channel is configured to supply air from outside of the fuel reservoir to a base of the flame. The air channel extends through the hollow wick and is at least partially graduated so that the flow of air through the air channel is substantially laminar.  
      In one embodiment, a lamp includes a fuel reservoir and a hollow wick. The fuel reservoir is configured to hold a volume of fuel. The hollow wick is configured to wick the fuel from the fuel reservoir to the atmosphere, such that a flame is produced when the wick is ignited. The lamp also includes means for controlling the flow of fuel and air in the vicinity of the flame, such that an adequate supply of fuel and air is available for combustion and the wind does not diminish or extinguish the flame.  
      Other systems, devices, methods, features, and advantages of the disclosed lamp will be apparent or will become apparent to one with skill in the art upon examination of the following figures and detailed description. All such additional systems, devices, methods, features, and advantages are intended to be included within the description and are intended to be protected by the accompanying claims.  
    
    
     BRIEF DESCRIPTION OF THE FIGURES  
      The present disclosure may be better understood with reference to the following figures. Matching reference numerals designate corresponding parts throughout the figures, and components in the figures are not necessarily to scale.  
       FIG. 1  is a perspective view of an embodiment of a lamp that includes means for controlling the flow of fuel and air in the vicinity of the flame.  
       FIG. 2  is a sectional view of the lamp of  FIG. 1 , taken along line  2 - 2 .  
       FIG. 3  is a perspective view of an embodiment of an elevating mechanism that can be coupled to the lamp shown in  FIG. 1 .  
       FIG. 4  is a sectional view of the elevating mechanism of  FIG. 3 , taken along lines  4 - 4 .  
       FIG. 5  is a perspective view of an embodiment of a smoke-encapsulating apparatus that can be coupled to the lamp shown in  FIG. 1 .  
       FIG. 6  is a sectional view of the smoke-encapsulating apparatus of  FIG. 5 , taken along line  6 - 6 . 
    
    
     DETAILED DESCRIPTION  
       FIG. 1  is a perspective view of an embodiment of a lamp  100 , and  FIG. 2  is a sectional view of the lamp taken along line  2 - 2 . The lamp  100  includes a fuel reservoir  102 , a hollow wick  104 , and an air channel  106 . The fuel reservoir  102  is configured to hold a volume of fuel  103 . The hollow wick  104  is configured to wick the fuel  103  from a lower end  110  to an upper end  112  of the wick, the lower end being positioned in the fuel reservoir  102  and the upper end being exposed to the atmosphere. The air channel  106  is configured to supply air  105  from the atmosphere on the outside of the fuel reservoir  102  through an interior of the wick  104  to an upper end  112  of the wick. The air channel  106  extends through the interior of the hollow wick  104  and the fuel reservoir  102  substantially surrounds a portion of an exterior of the wick, such that the wick is concentrically aligned with the air channel and the fuel reservoir. When the upper end  112  of the wick  104  is ignited, the fuel  103  burns to produce a flame  199 . The wick  104  and the air channel  106  feed the flame  199  with fuel  103  and air  105 , respectively, so that the flame is sustained. The air channel  106  is one of several means for controlling the flow of air  105  and fuel  103  in the vicinity of the flame  199 , as described below.  
      As shown in  FIG. 2 , the fuel reservoir  102  includes a fuel-retaining member  116  and a reservoir-enclosing member  118 . The fuel-retaining member  116  defines a cavity  120  for retaining the fuel  103 . The reservoir-enclosing member  118  defines a cover for enclosing the cavity  120 . The reservoir-enclosing member  118  removably engages the fuel-retaining member  116  so that the fuel-retaining member can be selectively opened and closed. When the reservoir-enclosing member  118  engages the fuel-retaining member, the cavity is substantially enclosed to prevent the fuel from escaping. When the reservoir-enclosing member  118  disengages the fuel-retaining member  116 , the cavity  120  is accessible so that fuel  103  can be introduced into the cavity.  
      The fuel reservoir  102  is formed from a plurality of walls  122 . In the illustrated embodiment, the walls  122  includes a lower wall  122   a , an outer side wall  122   b , an inner side wall  122   c , and an upper wall  122   d . The lower and side walls  122   a - c  form the cavity  120  of the fuel-retaining member  116 , with the inner side wall  122   c  also forming the boundary of the air channel  106 . The upper wall  122   d  forms the reservoir-enclosing member  118 . In the illustrated embodiment, the upper wall  122   d  forms an inner flange  138  that defines a neck  140  of the reservoir-enclosing member  118 , although in some embodiments the inner flange is omitted such that the reservoir-enclosing member does not form the neck.  
      In the illustrated embodiment, the fuel reservoir  102  is substantially cylindrical. The lower wall  122   a  is substantially a planar, annular disk. The outer side wall  122   b  is a cylindrical ring coupled to an outer perimeter of the lower wall  122   a  at a right angle. The inner side wall  122   c  is coupled to an inner perimeter of the lower wall  122   a  and has an inward taper  130 , as described below. The upper wall  122   d  is substantially a planar, annular disk. An outer flange  136  is coupled to an outer perimeter of the upper wall  122   d  and the inner flange  138  is coupled to the inner perimeter of the upper wall. In other embodiments, the fuel reservoir  102  may not be substantially cylindrical, in which case the walls  122  of the fuel reservoir may have other shapes and/or greater or fewer walls can be provided.  
      A coupling mechanism  124  enables removable engagement between the fuel-retaining member  116  and the reservoir-enclosing member  118 . In the illustrated embodiment, the coupling mechanism  124  is a series of threads on the fuel-retaining member  116  and the reservoir-enclosing member  118 . More specifically, the threads are formed on an interior surface of the outer side wall  122   b  and on an exterior surface of the outer flange  136  of the upper wall  122   d , such that the two pieces can be screwed together or apart. In other embodiments, the coupling mechanism  124  can have other configurations, such as a snap fitting or a friction fitting, in which case the threads and/or the outer flange  136  may be omitted. In still other embodiments, the reservoir-enclosing member  118  may not be removable, in which case the coupling mechanism  124  may be omitted and a port may be provided on the lamp  100  for refilling the cavity  120 .  
      As mentioned above, the reservoir-enclosing member  118  defines the neck  140  that projects away from the cavity  120 . The neck  140  is configured to support an adjustable collar  178 , which is described in detail below. An adjustment mechanism  142  enables adjusting the adjustable collar  178  with respect to the neck  140  between a lowered position in which the adjustable collar is relatively closer to the cavity  120  and a raised position in which the adjustable collar is relatively closer to the flame  199 . In other embodiments, the adjustable collar  178  may not be movable or may be omitted, in which cases the adjustment mechanism  142  or the entire neck  140  may be omitted.  
      In the illustrated embodiment, a lip  144  is formed adjacent the inner flange  138  that is configured to substantially close a space between the inner flange and the wick  104 , impeding the fuel  103  from escaping from the fuel reservoir  102 . In the illustrated embodiment, the inner flange  138  is substantially a cylinder that is coupled to the upper wall  122   d  at a right angle, and the lip  144  is substantially an annular ring coupled to an interior perimeter of the inner flange extending toward the wick  104 . In other embodiments, the neck  140  may have other configurations or may be omitted, in which cases the inner flange  138  and the lip  144  may be shaped differently or may be omitted.  
      In the illustrated embodiment, the adjustment mechanism  142  is a series of threads on an exterior surface of the inner flange  138  and on an interior surface of the adjustable collar  178 . In such case, the adjustable collar  178  can be rotated to move the collar with respect to the inner flange  138 . In other embodiments, the adjustment mechanism  142  may have other configurations. For example, the adjustment mechanism  142  may employ ratchets, pins and sockets, or friction.  
      The hollow wick  104  is positioned adjacent an exterior surface of the inner side wall  122   c  of the fuel reservoir  102 , such that the wick surrounds and is concentrically positioned with respect to the inner side wall. The upper end  112  of the wick  104  projects from a top of the fuel reservoir  102  adjacent the lip  144 , while the lower end  110  of the wick is positioned in the fuel reservoir. For example, the lower end  110  of the wick  104  may extend to substantially a bottom of the fuel reservoir  102  adjacent the lower wall  122   a  so that the wick exhausts the fuel  103  located at the bottom of the fuel reservoir  102 . The dimensions of the wick  104  are selected so that when the flame  199  is burning at the upper end  112 , the hollow interior of the wick is not so wide that the formation of a single flame is inhibited. The shape of the wick  104  is selected such that the wick conforms to the shape of the inner side wall  122   c , which in turn is determined by the shape of the air channel  106 , described below. The wick  104  may be made of any suitable material, such as glass fiber or metal mesh, as long as the wick draws the fuel  103  from the fuel reservoir  102 .  
      The fuel reservoir  102  may be formed from a variety of materials. For example, a metal or glass may be used. In some cases, the fuel reservoir  102  may be formed from a non-conductive material such as glass to inhibit heat transfer from the flame  199  to the fuel reservoir. Otherwise, the fuel reservoir  102  and/or the wick  104  may become hot. If the fuel reservoir  102  becomes hot, it may be dangerous to touch, or if the wick  104  becomes hot, the capillary action of the wick may supply an excessive volume of fuel  103  to the upper end  112  of the wick. In other cases, different walls  122  of the fuel reservoir  102  may be formed from different materials.  
      A variety of fuels  103  are suitable, including liquid fuels such as alcohol, liquid paraffin, mineral oil, and citronella oil. The fuel  103  can be selected to produce a flame  199  having certain characteristics. One characteristic that varies with the type of fuel  103  is the color of the flame  199 . For example, liquid paraffin produces a yellow flame, citronella oil produces a pink flame, oil blended with copper salts produces a green or blue flame, and oil blended with lithium salts produces a red flame. In some cases, a relatively heavy liquid fuel  103  can be used, such as vegetable oil or plant oil, because such fuels may be less likely to form fuel vapor, which may have an unpleasant odor.  
      The lamp  100  includes several means for controlling fuel  103  and air  105  in the vicinity of the flame  199 . As mentioned above, combustion requires a combination of fuel  103  and oxygen, the oxygen being at an adequately warmed temperature. The fuel  103  is provided to the flame  199  by the wick  104  and the oxygen is provided to the flame by the air  105  in the vicinity of the flame  199 . As the flame  199  burns, the fuel  103  is combusted and a replacement supply of fuel is provided by the wick  104 . If the flow of fuel  103  to the vicinity of the flame  199  is insufficient, the flame may diminish or extinguish entirely. If the flow of fuel  103  is excessive, the fuel may escape the vicinity of the flame  199  without being combusted. For example, the fuel  103  may escape in the form of smoke, fuel vapor or fuel droplets. The smoke may irritate the eyes, the fuel vapors may smell, and the fuel droplets may create a hazardous condition, all of which are undesirable. Also as the flame  199  burns, the oxygen is exhausted from the air  105  in the vicinity of the flame, creating a pressure on the flame from all sides and creating a low-pressure locus at substantially the center of a base  196  of the flame. A flow of air  105  toward the flame  199  can sustain the supply of oxygen available for the combustion process, and the air should be adequately warmed. If the flow of air  105  is insufficient, the supply of oxygen may be insufficient for complete combustion, and fuel  103  may escape the vicinity of the flame  199  without being combusted. If the flow of air  105  is excessive or turbulent, the flame  199  may be diminished or extinguished entirely, or the fuel  103  may be pushed away from the vicinity of the flame without being combusted. All of these are undesirable.  
      The various means for controlling fuel  103  and air  105  in the vicinity of the flame  199  increase the flow of air toward the flame such that the flame has an adequate supply of oxygen, and the oxygen is adequately warmed. For example, the means supply air  105  to the flame  199  from below, increasing combustion at an interior of the flame so that the flame develops a strong, wind-resistant backbone. The means also control the flow of air  105  in the vicinity of the flame  199 , such as by hindering wind and other air disturbances around the flame, such that the flame is not diminished or extinguished and fuel  103  is not dispersed from the vicinity of the flame without being combusted. The means also warm the air  105  so that the oxygen is adequately warmed. The means also control the flow of the fuel  103  such that the fuel is retained in the vicinity of the flame and is combusted, instead of escaping in the form of smoke or fuel vapor. Therefore, the means, alone or in combination, enable the production of a relatively larger, stronger, and more stable flame  199  that exhibits relatively improved combustion from a base to the top of the flame and from the interior to the perimeter of the flame. Although all of the means are described below with reference to the illustrated embodiment, a person of skill would appreciate that the means may be used independently or in any combination.  
      One such means for controlling fuel  103  and air  105  in the vicinity of the flame  199  is the air channel  106 . As mentioned above, the air channel  106  is configured to supply a flow of air  105  from outside of the fuel reservoir  102  to a base  196  of the flame  199 . The air channel  106  is at least partially graduated so that the flow of air  105  through the air channel is substantially laminar. An elevating mechanism  156  elevates the fuel reservoir  102  off a surface and creates a path from the outside of the fuel reservoir along an underside of the lower wall  122   a  and into the air channel  106 . As a result, a controlled volume of air  105  is directed from outside of the fuel reservoir  102  toward the flame  199 . In the illustrated embodiment, the elevating mechanism  156  is a plurality of feet coupled to the lower wall  122   a  of the fuel reservoir  102 , although the elevating mechanism can have any other configuration, including configurations that suspend the fuel reservoir from above. For example, the elevating mechanism  156  may be the projections described in U.S. Pat. No. 6,848,901 entitled “Apparatus for Controlling Characteristics of a Flame”, which issued on Feb. 1, 2005 to the Applicant of the present disclosure and is hereby incorporated by reference in its entirety. Further, the elevating mechanism  156  may be the outer side wall  122   b  of the fuel reservoir  102 . In such an embodiment, the lower wall  122   a  is elevated above a lower edge of the outer side wall  122   b  such that a gap or space is formed under the fuel reservoir. Air openings are formed in the portion of the outer side wall  122   b  between the lower wall  122   a  and the lower edge, so that air  105  can flow through the air openings and along the underside of the lower wall into the air channel.  
      The air channel  106  does not have a substantial cross-sectional area differentiation between a bottom  158  of the air channel adjacent the lower wall  122   a  and a top  160  of the air channel adjacent the upper end  112  of the wick  104 . In other words, the cross-sectional area  162  of the air channel  106  does not abruptly change between the bottom  158  and the top  160  of the air channel  106 . Instead, the cross-sectional area  162  of the air channel  106  either gradually changes or does not change. Specifically, the inner side wall  122   c  that forms the boundary of the air channel  106  has the inward taper  130  along at least a portion of a length of air channel, such that the cross-sectional area  162  of the air channel  106  gradually decreases or is substantially uniform over the length of the air channel. As a result, the interior surface of the inner side wall  122   c  is substantially free from sharp angles or rough edges. For example, the cross-sectional area  162  at the top  160  of the air channel  106  is smaller than the cross-sectional area  162  at the bottom  158  of the air channel.  
      In the illustrated embodiment, the air channel  106  continuously curves inward between the bottom  158  of the air channel, where the inner side wall  122   c  is substantially horizontal, and the top  160  of the air channel, where the inner side wall is substantially vertical. In other embodiments, the inward taper  130  of the air channel  106  can have other configurations. For example, the inward taper  130  may be linear from the bottom  158  to the top  160  of the air channel  106 , such that the cross-sectional area  162  of the air channel uniformly decreases between the bottom and the top of the air channel. As another example, only the lower portion of the air channel  106  may be tapered. In such a case, the air channel  106  may have the inward taper  130  between the bottom  158  of the air channel and an intermediate point between the bottom and the top  160  of the air channel. At the intermediate point, the inward taper  130  may disappear and the cross-sectional area  162  of the air channel  106  may remain constant between the intermediate point and the top  160  of the air channel. In this and in other cases, the air channel  106  may have a turn  161  at which the cross-sectional area  162  of the air channel  106  changes. For example, in the illustrated embodiment, the air channel  106  has a turn  161  at the bottom  158  of the air channel, where the lower wall  122   a  and the inner side wall  122   c  meet. However, in cases in which the air channel  106  has a turn  161 , the turn is graduated such that the cross-sectional area  162  of the air channel  106  gradually changes around the turn, reducing the tendency for air  105  traveling around the turn to become turbulent. For example, the turn  161  at the bottom  158  of the air channel  106  is rounded in  FIG. 2  so that the cross-sectional area  162  of the air channel gradually changes around the turn. In still other embodiments, the air channel  106  may not have the inward taper  130 , in which case the cross-sectional area  162  of the air channel may be substantially uniform, except at the bottom  158  of the air channel where the turn  161  into the air channel is graduated, such as rounded or tapered.  
      Because the interior surface of the air channel  106  is free from sharp corners, edges, the air channel is configured such that turbulence within the air  105  flowing through the air channel is reduced. Reducing turbulence is desirable because turbulence decreases the volume and velocity of air  105  reaching the flame  199 . For example, turbulent flow may pinch the air flow and may create a negative pressure within the air channel  106 , diverting air  105  out through the bottom  158  of the air channel and decreasing the volume of air reaching the flame  199 . Further, turbulent flow may decrease the velocity of the air  105  traveling toward the flame  199 . As mentioned above, providing a sustained flow of air  105  to the base  196  of the flame  199  increases combustion along a central backbone of the flame, improving the strength of the flame. Because a sustained flow of air  105  is provided at an increased velocity, the air channel  106  can have a relatively smaller cross-sectional area  162  adjacent the base  196  of the flame  199 , decreasing the width of the flame and increasing its strength.  
      Another means for controlling fuel  103  and air  105  in the vicinity of the flame  199  is a heat conductive element  163  positioned within the air channel  106 . The heat conductive element  163  is configured to increase the temperature of the air  105  located in the air channel  106 , reducing the pressure of the air and increasing the flow of air into the air channel. More specifically, the heat conductive element  163  receives heat from the flame  199  and transfers heat to the air  105  in the air channel  106 . The transferred heat increases the temperature of the air  105  and reduces the pressure of the air. As described below, the reduced pressure causes an increase in the flow of air  105  into the air channel  106  toward the flame  199 , and lowers the low-pressure locus of the flame. Additionally, the increased temperature of the air  105  also improves the combustion in the flame  199 , and reduces the pressure of the air in the flame.  
      The heat conductive element  163  may be a heat conductive rod  164 , a heat conductive tube  166 , or both. The heat conductive rod  164  extends from the top  160  of the air channel  106  in a downward direction D. The heat conductive rod  164  may be any suitable material, such as metal. Although a heat conductive rod  164  having a substantially circular cross-section and positioned substantially in the center of the air channel  106  may be less likely to cause turbulence within the air channel and may enable more even warming, the heat conductive rod  164  may be any suitable shape and may be positioned anywhere in the air channel  106 , so that an appropriate flow of air  105  through the air channel is produced.  
      The heat conductive tube  166  lines at least a portion of the interior surface of the air channel  106  and extends from the top  160  of the air channel in the downward direction D. The heat conductive tube  166  can be any suitable heat conductive material, such as metal. In some cases, the heat conductive tube  166  is a single layer or multiple layers of heat conductive material. In other cases, a mesh material is used such that air  105  can flow through the heat conductive tube  166  for further warming. In still other cases, heat radiation fins extend from the heat conductive tube towards the center of the heat conductive tube, such that air  105  flowing through the heat conductive tube  166  is further warmed.  
      The heat conductive elements  163  may vary depending on the material and shape of the air channel  106 . For example, in cases in which the air channel  106  has a relatively large cross-sectional area  162 , both the heat conductive rod  164  and the heat conductive tube  166  may be used. In cases in which the air channel  106  has a relatively small cross-sectional area  162 , one of these heat conductive elements  163  may be omitted. Further, a plurality of heat conductive rods  164  may be employed in some cases, such as in cases in which the air channel  106  has a relatively large cross-sectional area  162  or in cases in which the heat conductive tube  166  is omitted. For example, the heat conductive tube  166  may be omitted in cases in which the inner side wall  122 c is a heat conductive material.  
      In any case, the heat conductive elements  163  are heated by the flame  199  from the top  160  of the air channel  106  in the downward direction D. As a result, the air pressure increases in the downward direction D such that the air pressure at the top  160  of the air channel  106  is relatively lower than the air pressure at the bottom  158  of the air channel. The pressure differential between the top  160  and the bottom  158  of the air channel  106  encourages the movement of air  105  along the air channel in an upward direction U, increasing the volume and the velocity of the air  105  flowing toward the flame  199 . In the illustrated embodiment, both the heat conductive rod  164  and the heat conductive tube  166  extend from the top  160  of the air channel  106  to substantially the bottom  158  of the air channel, but in other embodiments one or both of the heat conductive elements  163  may not extend to the bottom of the air channel. Positioning the heat conductive element  163  at only the top  160  of the air channel  106  may be desirable, so that the transferred heat increases the temperature of the air  105  at the top of the air channel to create the pressure differential instead of increasing the temperature of the air along the entire air channel.  
      The flow of air  105  supplies the flame  199  with the oxygen needed for combustion. Because the flow of air  105  to the flame  199  is controlled and continuous, the flame is relatively less likely to diminish in size or extinguish. Further, because the flow of air  105  is supplied through the air channel  106 , the flame  199  receives oxygen from the base  196  where oxygen is normally absent, enabling more complete combustion within the interior of the flame. As a result, the flame  199  is stronger and is less susceptible to air disturbances such as wind. The lower air-pressure at the top  160  of the air channel  106  also moves the low-pressure locus of the flame  199  in the downward direction D, which also makes the flame  199  stronger and less susceptible to air disturbances. Because the air  105  is warmed before reaching the flame  199 , the oxygen in the air is better suited for combustion, and the combustion process is relatively more complete.  
      A layer of insulation  168  may line the inner side wall  122   c . The layer of insulation  168  maintains the heat that has been transferred to the air channel  106 . In cases in which the inner side wall  122   c  is made from a heat conductive material, the layer of insulation  168  may be provided between the inner side wall and the heat conductive tube  166  so that heat from the heat conductive tube  166  is not transferred through the inner side wall to the wick  104 . Increasing the temperature of the inner side wall  122 c and the wick  104  decreases the amount of energy available to warm the air  105  in the air channel  106 , such that the desired low pressure effect may not be created to the extent possible. Further, increasing the temperature the wick  104  may increase the capillary action of the wick, such that a relatively larger volume of fuel  103  is directed to the upper end  112  of the wick. In cases in which the larger volume of fuel  103  cannot be efficiently combusted, excess fuel may spill from the lamp  100  or may be converted into smoke or fuel vapor. The layer of insulation  168  is configured to address these issues.  
      Another heat conductive element  163  is a permeable cover  170  adjacent the base  196  of the flame  199 . The permeable cover  170  is formed from any suitable heat conductive material, such as metal, and is permeable so that air  105  can flow through the cover to the flame  199 . The permeable cover  170  absorbs heat from the flame  199  and transfers the heat to the air  105  adjacent the base  196  of the flame. Because the air  105  is warmer when it reaches the flame  199 , combustion is more efficient at the base  196  and interior of the flame  199 . Further, the warmer air  105  reduces the air pressure adjacent the base  196  of the flame  199 . The reduced air pressure increases the flow of air  105  toward the base  196  of the flame  199  to improve combustion, and lowers the low-pressure locus of the flame to strengthen the flame. Further, the permeable cover  170  captures unburned particles of fuel  103  that have descended in the downward direction D and rapidly heats the unburned particles of fuel so that combustion occurs. Therefore, the permeable cover  170  reduces the unburned particles of fuel  103 , and therefore the smoke and fuel vapors, that escape the vicinity of the flame  199  without being burned.  
      The permeable cover  170  is positioned at the top  160  of the air channel  106 . In the illustrated embodiment, the permeable cover  170  is sized to span the cross-sectional area  162  of the air channel  106  at the top  160  of the air channel and to overlap the wick  104  adjacent the air channel. The permeable cover  170  rests on the wick  104  without being coupled to the wick. In other embodiments, the permeable cover  170  can have other configurations. For example, the permeable cover  170  may be relatively larger or smaller, or may be affixed to the lamp  100 . The permeable cover  170  serves the additional function of supporting the heat conductive rod  164 . More specifically, the heat conductive rod  164  hangs suspended from the top  160  of the air channel  106  about the permeable cover  170 .  
      Another means for controlling fuel  103  and air  105  in the vicinity of the flame  199  is a permeable collar  172 . The permeable collar  172  is configured to substantially surround at least the base  196  of the flame  199 . In addition to being permeable by air  105  and fuel  103 , the permeable collar  172  is made from a heat conductive material, such as a metal mesh. The heat of the flame  199  increases the temperature of the permeable collar  172  so that the permeable collar can warm the air  105  and fuel  103  adjacent the flame  199 . As explained above, increasing the temperature of the air  105  encourages the movement of a controlled volume of air around the flame  199 , while increasing the temperature of the fuel  103  in the vicinity of the flame facilitates complete combustion. More specifically, the permeable collar  172  may capture particles of fuel  103  that have escaped the vicinity of the flame  199 . For example, the wind may push the fuel  103  away from the vicinity of the flame before the fuel is combusted. As another example, large particles of fuel  103  may be inadequately combusted, and may be moved away from the flame  199  before the combustion process is complete. In such cases, the permeable collar  172  captures the escaping fuel  103  and rapidly heats the fuel, breaking the fuel into smaller particles and retaining the fuel in the vicinity of the flame  199 , so that the fuel catches fire for complete combustion.  
      Another means for controlling fuel  103  and air  105  in the vicinity of the flame  199  is a continuous collar  174 . The continuous collar  174  is also configured to substantially surround at least the base  196  of the flame  199 , forming a shield to block the wind or other air disturbances and to limit the escape of particles of fuel  103 . In some embodiments, the continuous collar  174  may be formed from a heat conductive material to further promote the flow of warm air  105  to the flame  199  and to further promote complete combustion at the base  196  of the flame, as described above. The continuous collar  174  may also be formed from a translucent material, so that the light generated by the flame  199  is visible through the continuous collar. The continuous collar  174  is also configured to control the direction of outside air toward the flame, as described in U.S. Pat. No. 6,848,901, entitled “Apparatus for Controlling Characteristics of a Flame,” which issued on Feb. 1, 2005 to the Applicant of the present disclosure and is hereby incorporated by reference in its entirety. The continuous collar  174  can be moved between a raised and lowered position to adjust the volume of air  105  reaching the flame  199 , and therefore the height of the flame. The continuous collar  174  may have holes  175  formed through it, such that air  105  can pass through the holes. The air passing through the holes  175  is warmed by the continuous collar  174 , and is further warmed by the permeable collar  172 , facilitating complete combustion and forming an air shield that protects the flame  199 . In some embodiments, the holes  175  are located at the bottom of the continuous collar  174 , so that the air adjacent the bottom of the flame  199  is warmed, reducing heavy combustion gases that may otherwise stay at the bottom.  
      The continuous collar  174  and the permeable collar  172  are concentrically disposed with respect to the air channel  106  and the wick  104 . In the illustrated embodiment, the permeable collar  172  is a cylindrical ring formed from a metal mesh, and the continuous collar  174  is also a cylindrical ring. The air channel  106  is substantially surrounded at the top  160  by the wick  104 , which is substantially surrounded by the permeable collar  172 , which is substantially surrounded by the continuous collar  174 . Such a configuration enables the continuous collar  174  and the permeable collar  172  to be adjacent the base  196  of the flame  199  so that the collars can perform their intended functions while being spaced apart from the wick  104 . Separating the collars  172 ,  174  from the wick  104  limits heat transfer between the collars and the wick so that capillary action of the wick is not increased. The separation also enables positioning the lip  144 , and a series of drain and vent holes  176  formed through the lip, adjacent the flame  199 . The drain and vent holes  176  provide an avenue for large particles of un-combusted fuel  103  to return to the cavity  120  within the fuel reservoir  102 . The drain and vent holes  176  also allow air to flow into the cavity  120  to replace the fuel  103  removed by the wick  104 , equalizing the pressure within the cavity so that a vacuum is not created. Because the drain and vent holes  176  are positioned adjacent the flame  199 , fuel vapors that escape from the drain and vent holes are brought into the vicinity of the flame and are combusted instead of escaping into the atmosphere, potentially creating a foul odor. Therefore, the drain and vent holes  176  are another means for controlling the flow of fuel  103  and air  105  in the vicinity of the flame  199 .  
      The continuous collar  174  and the permeable collar  172  can be moved between a lowered position, in which the collars are lowered in the downward direction D, and a raised position in which the collars are raised in the upward direction U. Moving the collars  172 ,  174  between the lowered position and the raised position provides the lamp  100  with greater flexibility of use. For example, the collars  172 ,  174  adjust the direction of air supply to the flame  199 , thereby affecting the height of the flame, and may be raised in windy conditions and lowered in more stable air conditions, to selectively shield the flame  199  from wind and other air disturbances, and/or to limit the escape of particles of fuel  103 .  
      In the illustrated embodiment, both of the collars  172 ,  174  are supported by the adjustable collar  178  and extend from the adjustable collar  178  in the upward direction U. The continuous collar  174  is coupled to the adjustable collar  178  and the permeable collar  172  rests against the continuous collar on the interior of the continuous collar. The continuous collar  174  and the permeable collar  172  can be moved between the raised and lowered positions by adjusting the adjustable collar  178  with respect to the neck  140  using the adjustment mechanism  142 , as described above. In other embodiments, the continuous collar  174  and the permeable collar  172  can be adjusted in other manners, or the collars may not be adjustable.  
      In addition to supporting the continuous collar  174  and the permeable collar  172  and enabling their adjustment, the adjustable collar  178  is also a means for controlling fuel  103  and air  105  in the vicinity of the flame  199 . The adjustable collar  178  is configured to shield the flame  199  from the wind, and to enable a cushion of warm air to form around the flame  199  that limits the impact of the wind on the flame.  
      In the illustrated embodiment, the adjustable collar  178  is substantially a circular plate having a flange  180  extending from an outer perimeter of the circular plate in the upward direction U. The adjustable collar  178  is coupled to the neck  140  of the fuel reservoir  102  such that the circular plate is substantially parallel to the upper wall  122 d and the flange  180  extends away from the upper wall in the upward direction U. The flange  180  is configured to block the wind that may diminish or extinguish the flame  199 .  
      Additionally, the adjustable collar  178  has openings  182  that are configured to assist with the formation of the air cushion around the flame  199 . Because the air  105  located above the adjustable collar  178  in the upward direction U is relatively warmer than the air located below the adjustable collar in the downward direction D, a pressure differential is created across the adjustable collar that drives the air through the openings  182  in the upward direction. This air  105  forms a cushion around the flame  199  that lessens the impact of the wind. As shown in the illustrated embodiment, the openings  182  may be graduated or tapered such that the flow of air  105  through the openings is substantially laminar. For example, the openings  182  may be substantially conical in shape.  
       FIG. 3  is a perspective view of an embodiment of an elevating mechanism  300  that is configured to elevate a lamp such as the lamp  100 , and  FIG. 4  is a sectional view of the elevating mechanism  300  taken along lines  4 - 4 . The elevating mechanism  300  includes a casing  302 . Although the casing  302  can have any shape, in the illustrated embodiment the casing is substantially a cylinder. An interior of the casing  302  is shaped to mate with the lamp  100 . More specifically, an inner diameter of the casing  302  at a top  306  of the casing is greater than an outer diameter of the lamp  100 , such that the lamp can be inserted into the top of the casing.  
      The casing  302  includes a support mechanism  308  configured to support the lamp  100 . As shown, the support mechanism  308  is a ledge spaced apart from the top  306  of the casing  302  in the downward direction D. When the lamp  100  is inserted into the casing  302 , the lamp rests on the ledge. Alternatively, the support mechanism  308  can be something other than the ledge.  
      The casing  302  also includes air entrances  312  positioned at a bottom  307  of the casing that are in fluid communication with the air channel  106  of the lamp  100 . Air  105  that flows through the air entrances  312  is directed into the air channel  106  of the lamp  100  to feed the flame  199 .  
      The elevating mechanism  300  also includes a stake  314  that elevates the casing  302 . The stake  314  is an elongated rod that is configured to support the casing  302  and the lamp  100  when a lower end  313  of the stake is inserted into the ground. The stake  314  may be coupled to the casing  302  in any manner. For example, the casing  302  may have a coupling  316  that is configured to engage the stake  314 . In the illustrated embodiment, the coupling  316  is a cylindrical ring having threads on an interior surface that are configured to engage threads on an upper end  315  of the stake  314 . In other embodiments, the stake  314  and the coupling  316  may have other configurations. Alternatively, the coupling  316  may be omitted, and the stake  314  may be permanently coupled to the casing  302 .  
      In some embodiments, the elevating mechanism  300  includes an air entry channel  318  that is in substantially seamlessly fluid communication with the air channel  106  of the lamp  100 . In such embodiments, the elevating mechanism  300  is another means for controlling fuel  103  and air  105  in the vicinity of the flame  199 . However, the air entry channel  318  is not necessary and can be omitted.  
      The air entry channel  318  is substantially a truncated cone defined by an exterior wall  320  and an interior wall  322 . The air entrances  312  are formed in the interior wall  322  and are in fluid communication with the air entry channel  318 , which in turn is in fluid communication with the air channel  106  of the lamp  100 . As a result, air  105  that flows through the air entrances  312  is directed through the air entry channel  318  and into the air channel  106  of the lamp  100 . The air entrances  312  are not directly exposed to the wind, so that during windy conditions, turbulent air is not directed into the air entry channel  318 .  
      The air entry channel  318  may be at least partially graduated so that the flow of air  105  through the air entry channel is substantially laminar. The exterior wall  320  and the interior wall  322  may be substantially free from rough corners and sharp edges. For example, the exterior wall  320  and the interior wall  322  may gradually taper inward. In the illustrated embodiment, both the exterior wall  320  and the interior wall  322  are curved such that the air entry channel  318  is a curved conical shape, with a width  324  of the air entry channel  318  gradually decreasing from the bottom  307  of the casing  302  in the upward direction U. In other embodiments, other configurations are possible.  
      The shape of the air entry channel  318  encourages the laminar flow of air  105  through the air entry channel and into the air channel  106  of the lamp  100 . Turbulence is also reduced by placing the air entrances  312  on the bottom  307  of the casing  302  along the interior wall  322 . In cases in which the width  324  of the air entry channel  318  gradually decreases from the bottom  307  of the casing  302  in the upward direction U, the velocity of air  105  traveling through the air entry channel may be increased. For example, in the illustrated embodiment the width  324   a  of the air channel  106  at the top  306  of the casing  302  is less than the width  324   b  of the air channel at the bottom  307  of the casing.  
      In the illustrated embodiment, the interior of the casing  302  is shaped to form the exterior wall  320  of the air entry channel  318  and the ledge. The interior of the casing  302  curves inward from the bottom  307  of the casing  302  in the upward direction U, and at a point between the top  306  and the bottom  307 , the inward curve abruptly ends. At this point, the ledge is formed. The interior wall  322  is coupled to the casing  302  at the bottom  307  of the casing and diverges inward so that the interior wall is spaced apart from the exterior wall  320 . The interior wall  322  is substantially a cone having an apex  326  that extends into the air channel  106  of the lamp  100 . The coupling  316  is coupled to the interior wall  322  adjacent the apex  326  on an exterior of the casing  302 , so that the coupling is centrally positioned. However, in other embodiments other configurations are possible.  
       FIG. 5  is a perspective view of an embodiment of a smoke-encapsulating apparatus  500  that can be coupled to a lamp such as the lamp  100 , and  FIG. 6  is a sectional view of the smoke-encapsulating apparatus of  FIG. 5 , taken along line  66 . The smoke-encapsulating apparatus  500  includes a housing  502  that is configured to substantially enclose a volume of smoke  504 . For this reason, the housing  502  is substantially enclosed except for an entry port  506  and an exit port  508 . In the illustrated embodiment, the housing  502  is substantially box-shaped, although other configurations are possible.  
      The entry port  506  is an opening formed in the housing  502  that is configured to receive a smoke-producing device  510 , such as a cigarette or a cigar. The smoke-producing device  510  can be placed through the entry port  506  such that a burning end  512  of the smoke-producing device is positioned within an interior of the housing  502  while a non-burning end  518  of the smoke-producing device is positioned on an exterior of the housing. In the illustrated embodiment, the entry port  506  is substantially a circular opening formed in a side  520  of the housing  502 , although other configurations are possible. For example, the entry port  506  may be circular or rectangular. The entry port  506  may also be substantially uniform in diameter to hold the smoke-producing device  510  horizontally, except at a rim  522  where the entry port  506  is rounded or tapered. An interior surface of the rim  522  may be inwardly tapered to direct the smoke  504  into the housing  502 . In embodiments not shown, the housing  502  may have a plurality of entry ports  506  such that the smoke-encapsulating apparatus  500  can be used with a plurality of smoke-producing devices  510  simultaneously.  
      The exit port  508  is configured to communicate smoke  504  from the housing  502  to the lamp  100 . The lamp  100  can be placed on the smoke-encapsulating apparatus  500  such that the exit port  508  is in fluid communication with the air channel  106  of the lamp  100 . The smoke  504  is then directed into the air channel  106  and is burned as fuel  103  by the flame  199 . In the illustrated embodiment, the exit port  508  is substantially a circular opening formed in a top  526  of the housing  502 , although other configurations are possible. In some embodiments, the exit port  508  may have a shape that matches the cross-sectional area  162  of the air channel  106  at the bottom  158  of the air channel. Some embodiments may also be configured such that the lamp  100  can be coupled to the smoke-encapsulating apparatus  500  instead of resting on the smoke-encapsulating apparatus.  
      In some embodiments, the smoke-encapsulating apparatus  500  is configured to direct smoke  504  from the entry port  506  to the exit port  508 . For example, the illustrated embodiment includes an exit tube  528  that extends from the exit port  508  in the downward direction D. The exit tube  528  is configured to direct smoke  504  to the exit port  508  so that the smoke is communicated into the air channel  106  of the lamp  100 . In some embodiments, the exit tube  528  has a cross-sectional area  530  that is relatively larger at a bottom than at a top of the exit tube. The cross-sectional area  530  may gradually decrease in the upward direction U so that the smoke  504  is drawn along the exit tube  508  in the upward direction U. The larger and heavier particles of smoke  504  that may be inclined to stay at the bottom of the housing may be directed up the exit tube  528  to the exit port  508 . However, the exit tube  528  is not necessary and can be omitted. The housing  502  may also be contoured on the interior of the housing to direct the smoke  504  toward the exit port  508 .  
      The smoke-encapsulating apparatus  500  is useful for capturing second-hand smoke  504  and providing the second-hand smoke to the lamp  100 , which combusts the smoke. Generally, the smoke-producing device  510  produces relatively larger particles of smoke  504  during puffing and produces relatively smaller particles of smoke when idle. The larger particles of smoke  504  can be filtered from the air using an air filter, while the smaller particles of smoke pass through the air filter without being captured. Therefore, the smoke-encapsulating apparatus  500  is configured to capture the smoke  504  created when the smoke-producing device  510  is idle. The smoke  504  can be combusted by the lamp  100  to produce the flame  199 , including smaller particles of smoke that otherwise would not be filtered out of the air.  
      In some embodiments, the lamp  100  may include more than one hollow wick  104 . For example, the lamp  100  may include two hollow wicks  104  that are concentrically disposed, as described in the U.S. Pat. No. 6,896,510 entitled “Apparatus and Methods for Controlling a Flame”, which issued on May 24, 2005 to the Applicant of the present disclosure, and which is hereby incorporated by reference in its entirety. In such an embodiment, each of the wicks  104  produces a distinct and separate flame. It may be desirable to use a lamp  100  that includes more than one hollow wick  104  in combination with the smoke-encapsulating apparatus  500 , because such a lamp creates a relatively larger flame and therefore is configured to eliminate a relatively larger volume of smoke  504 . However, using such a lamp  100  is not necessary, in which case a lamp having a single hollow wick  104  can be employed.  
      While particular embodiments of the lamp have been disclosed in detail in the foregoing description and figures for purposes of example, those skilled in the art will understand that variations and modifications may be made without departing from the scope of the disclosure. All such variations and modifications are intended to be included within the scope of the present disclosure, as protected by the following claims.