Patent Publication Number: US-6209795-B1

Title: Camping apparatus for heating a portable habitation and method

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to camping apparatus for heating the interior of a portable habitation and, more particularly, to such camping apparatus that a fire to provide heated air to an interior heater in the portable habitation. 
     Hunters, explorers, geologists and other campers commonly use a portable habitation, such as a tent, for resting and sleeping. Sometimes during cold weather, these individuals find fuel, such as wood from trees, near the campsite to provide an open fire in the habitation to make themselves comfortable. Sometimes a camp stove is brought along with the habitation primarily for cooking food and secondarily for heating the habitation. 
     The use of an open fire in the habitation is extremely dangerous because the open fire inside can envelop the material used to make the habitation and destroy it. In which event, the people in the habitation can be injured by the ensuing fire or by the cold weather existing outside of the habitation. Also, it is extremely dangerous because an open fire inside the habitation may emit harmful or deadly gases, such as carbon monoxide, directly into the habitation. In which event, the people in the habitation can be asphyxiated. 
     A combination heater and catalytic converter is available to provide heat within a habitation. However, the heat generated from a catalytic converter can be sufficiently hot to cause the material of the habitation to burn. In which event, the fire could envelop the material used to make the habitation and destroy it with the people in the habitation being injured by the ensuing fire or by the cold weather existing outside of the habitation. 
     Accordingly, it is an object of the present invention to provide apparatus for heating the interior of a portable habitation. 
     Further, it is an object of the present invention to provide apparatus for heating the interior of a portable habitation that uses a fire, which is positioned away from the habitation by a distance sufficient to prevent damage to the habitation from the fire. 
     Further, it is an object of the present invention to provide a method of providing heat to the interior of a portable habitation. 
     Further, it is an object of the present invention to provide a method of providing heat to the interior of a portable habitation by using a fire that is positioned away from the habitation by a distance sufficient to prevent damage to the habitation from the fire. 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided apparatus for heating an interior of a portable habitation. The apparatus comprises an interior heater for heating the interior of the portable habitation. A heat transfer device uses fumes emitted by a fire to provide heated air. Transporting apparatus transports the heated air from the heat transfer device to the interior heater. The interior heater is disposed at a first location and the fire is disposed at a second location, the first and second locations being disposed sufficiently apart from one another to prevent the fire at the second location from spreading to the portable habitation at the first location. The transporting apparatus has a length sufficient to extend between the first and second locations. 
     Further, in accordance with the present invention, there is provided camping apparatus for heating an interior of a portable habitation. The camping apparatus comprises an interior heater for heating the interior of the portable habitation, which is disposed at a first location. A heat transfer device uses fumes emitted by a fire to provide heated air. The fire is disposed at a second location. The first and second locations are disposed sufficiently apart from one another to prevent the fire at the second location from spreading to the portable habitation at the first location. The heat transfer device includes a chimney to transport fumes emitted by the fire away from the fire. The chimney includes a center that is constructed with sidewalls tapering toward one another away from the fire. A plurality of fins for transferring heat from the fumes is connected to and extends away from the chimney. Each of the plurality of fins is constructed to have a curved surface for urging the air being heated into a flow around the chimney. A sleeve containing a quantity of air detachably is connected to and disposed around the chimney outwardly of the fins. The sleeve includes an interior to contain the quantity of air. An air inlet for allowing the quantity of air to be continuously supplemented is disposed in fluid communication with the interior. A heated air outlet for allowing the quantity of air to be continuously exhausted is disposed in fluid communication with the interior. Transporting apparatus transports the heated air from the heat transfer device to the interior heater. The transporting apparatus has a length sufficient to extend between the first and second locations and an elongated tube connected to the heated air outlet of the sleeve. A burner providing a continuous fire is fed by fuel supplied by a fuel tank. A connector connects the burner to the heat transfer device and includes positioning apparatus for centering the burner relative to the center of the chimney. The positioning apparatus has at least three screw members threadedly connected to and disposed to extend inwardly to engage the fuel tank. 
     Further, in accordance with the present invention, there is provided a method of providing heat to an interior of a portable habitation. The method comprises the steps of choosing a first location to place the portable habitation. The minimum distance from the first location where a fire may be used outside of which the fire may be used that will not spread to the portable habitation is determined. A fuel tank is positioned at a second location chosen outside of the minimum distance. A burner is attached to the fuel tank. A chimney is mounted over the burner. One end of a transporting apparatus is connected to the sleeve and another end of the transporting apparatus is connected to a heat transfer device in the portable habitation. A fire is started on the burner and air is passed through the sleeve while fuel is being burned by the burner. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     Objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings, wherein like reference characters are used throughout to designate like parts: 
     FIG. 1 is a view of the components of a camping apparatus constructed according to the present invention; 
     FIG. 2 is a view, in elevation and partly in section, of a heat transfer-connector of the apparatus shown in FIG. 1; and 
     FIG. 3 is a view, in elevation and partly in section, of a sleeve used to contain the heat transfer portion the apparatus shown in FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning now to FIG. 1 of the drawing, there is shown a camping apparatus  10  for heating an interior  12  of a portable habitation  14 . The portable habitation is of conventional construction, such as a tent having four or more walls  16  made from a conventional material, such as canvas, that may be with or without a floor (not shown). 
     An interior heater  18  is provided for heating interior  12  of portable habitation  14 . Interior heater  18  is disposed at a first location  20  and is constructed in a box  22  configuration with a plurality of walls  24  enclosing an electrical motorized fan  26 . Fan  26  forces heated air from the inside of box  22  through louvers  28  into interior  12  and is regulated by a conventional thermocouple  30  or similar conventional device connected by a conventional electrical operating circuit  32 . 
     A heat transfer device  34  uses fumes emitted by a fire  36  to provide heated air. The fire  36  is disposed at a second location  38 . As best seen in FIGS. 1 and 2, first location  20  and second location  38  are disposed sufficiently apart from one another to prevent the fire at second location  38  from spreading to portable habitation  14  at first location  20 . 
     Heat transfer device  34  has a chimney  40  for transporting the fumes emitted by fire  36  away from fire  36 . Chimney  40  has a center  42 , which is preferably an axis of symmetry, and is constructed with sidewalls  44  tapering toward one another the further chimney  40  is away from fire  36 . Thus, chimney  40  has the general shape of a truncated cone with fire  36  being disposed at a base  46  of the cone and the truncated portion  48  of the cone forming the outlet for the fumes from fire  36 . Chimney  40  has a height sufficient to prevent fire  36  from passing outwardly of heat transfer device  34  into the surrounding area. 
     Extending outwardly from and connected to sidewalls  44  are four fan tiers  50 ,  52 ,  54  and  56 , respectively, with each tier having a plurality of fins for transferring heat from sidewalls  44  that have been heated by fumes from fire  36 . It is preferred that first fan tier  50  has four fins  58 , second fan tier  52  has four fins  60 , third fan tier  54  has four fins  62  and fourth fan tier  56  has four fins  64 . To urge the air being heated into a flow around chimney  50  and thereby assist in heat transfer from the plurality of fins, each of the four fins  58 ,  60 ,  62  and  64  is constructed to have a curved surface  66  that forms an angle Θ between its tangent and a plane formed for each fan tier. When desired, angle Θ changes with each fan tier to further assist in heat transfer as the air flows from base  46  to outlet  48  of chimney  40 . 
     As best seen in FIGS. 1 and 3, a sleeve  68  for containing a quantity of air  70  is detachably connected to and disposed around chimney  40  outwardly of the plurality of fins  58 ,  60 ,  62  and  64 . Sleeve  68  has sidewalls  72  in the shape of a tube and a top  74  blocking the tube. Sidewalls  72  and top  74  create an interior  76  that, along with chimney  40  and the plurality of fins  58 ,  60 ,  62  and  64  define and contain quantity of air  70 . A plurality of ambient air inlets  78  disposed in fluid communication with interior  76  are disposed around sidewalls  72  and at an end away from top  74  for allowing quantity of air  70  to be continuously supplemented. A heated air outlet  80  for allowing the quantity of air  70  to be continuously exhausted is disposed through sidewalls  72  in fluid communication with interior  76 . A tube  82  extends outwardly of sidewalls  72  around heated air outlet  80 . 
     Transporting apparatus  84  is used to transport the heated air from heat transfer device  34  to interior heater  18 . Transporting apparatus  84  has an elongated tube  86  with a length sufficient to extend between first location  20  and second location  38 . Elongated tube  86  has a first end  88  connected by a coupler  90  to tubular member  82 , which is disposed around heated air outlet  80  of sleeve  68 , and a second end  92  connected by a coupler  94  to interior heater  18 . Tube  86  may be constructed from a single tubular element, several tubular elements or a flexible tube so long as the length is sufficient to extend between first location  20  and second location  38  and such length is maintained during use of camping apparatus  10 . 
     A burner  96  is used to provide a continuous fire and is fed by fuel supplied by a fuel tank  98 . Burner  96  and fuel tank  98  are of conventional design. When using camping apparatus  10  in a area where all of the waste material to be removed with the camper when leaving, it is preferred that fuel tank  98  support a fluid fuel, such as liquid propane or natural gas. Burner  96  is constructed to be attached to conventional outlet apparatus  100  on tank  98  so that fluid communication may exist between burner  96  and tank  98 . Burner  96  is selected to burn the fluid at an optimum rate. Burner  96  and tank  98  have axes of symmetry that are disposed coincident to one another with properly connected by connecting apparatus  100 . 
     Connector apparatus  102  is used to connect burner  96  and tank  98  to heat transfer device  34 . Connector apparatus  102  includes a tubular connecting sleeve  103  with an axis of symmetry and with a size sufficient to encircle burner  96  and a portion of tank  98 . A positioning apparatus  104  is used to center the axes of symmetry of burner  96  and tank  98  to be coincident with axis of symmetry  42 . Positioning apparatus  104  includes at least three screw members  106 , preferably four screw members  106 , threadedly connected to sleeve  103 . Each screw member  106  has a contacting end  108  with an engaging pad  110  for engaging tank  98  disposed inwardly of sleeve  103  and an outside end  112  that has a hand wheel  114  connected thereto for urging engaging pad  110  into and out of engagement with tank  98  when rotated. By proper positioning of tank  98  in sleeve  103  and proper manipulation of hand wheels  114 , the axes of symmetry of burner  96  and tank  98  are disposed to lie coincident with axis of symmetry  42 . 
     As best seen in FIG. 1, to provide adequate air to be provided to fire  36 , apertures  116  are provided in sleeve  103  at an elevation beneath fire  36  and burner  96 . It is preferred that four apertures  116  be used and that they be disposed in a radial fashion equally around sleeve  103 . 
     An intermediate member  118  constructed in the shape of a truncated cone is disposed between and interconnects base  46  of chimney  40  to the top of sleeve  103 . 
     Four upwardly extending connecting members  120  are connected to the top of sleeve  103  to support sleeve  68  when positioned around fins  36  and chimney  40 . Although three connecting member  120  may be used to support sleeve  68  on sleeve  103 , it is preferred that four members  120  be used to provide additional support. In either event, it is preferred that members  120  be disposed in a radial fashion equally around sleeve  103 . 
     To allow fluids, which may flow through ambient air inlets  78  into interior  76  of sleeve  68 , to drain from the connection between sleeve  68  and sleeve  103 , notches  112  are provided in the lower surface of sidewalls  44 , as shown in FIG.  3 . 
     To provide heat to interior  12  of portable habitation  14 , first location  20  to place portable habitation  14  is chosen. The minimum distance from first location  14  where fire  365  may be used outside of which fire  36  will not spread to portable habitation  14  is determined. Fuel tank  09  is positioned at second location  38 , which is outside of the determined minimum distance. Burner  96  is attached to fuel tank  98 . Chimney  40  is mounted over burner  96 . First end  88  of transporting apparatus  84  is connected to sleeve  68  and second end  92  of transporting apparatus  84  is connected to heat transfer device or heater  18  in portable habitation  14 . Fire  36  is started on burner  96 . Air passes through apertures  116  while fuel is being burned by burner  98 . Fan  26  is provided in heat transfer device  18  in portable habitation  14 . Fan  26  is activated to draw heated air through transporting apparatus  84  and ambient air into sleeve  68 . Burner  96  is adjusted to provide an optimum fire at fire  36 .