Abstract:
A heating stove for burning a gelled alcohol fuel is provided which is constructed of cast iron, yet nevertheless, is compact and light enough for one person to move. The stove is constructed of a minimum of parts, with a duplication of some parts, to minimize production and assembly costs and time. The stove provides for visibility of the burning flame of the fuel and yet confines the flame for safety considerations.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to the use of cast iron in the manufacture of portable stoves for use by the general public. More specifically, the stove of the present invention is designed to burn cans of fireplace fuel better known as gelled alcohol, and for this reason the stove has been designed without exterior venting capabilities. 
     Stoves in use today for heating an indoor enclosed space are generally made of welded steel construction, cast iron or a combination of both for use in cooking and heating. Some stoves are designed for the use of natural gas as the fuel. These stoves may be ventless, but at the same time require a connection to a gas supply. Like woodburning stoves, once they are in place, they cannot easily be moved about without the need to either re-vent (if they have a vent) or at least be connected to a new gas line. Also these types of stoves are generally heavy and require several people to be able to move them. As with the ventless gas burning stoves, there is also the concern of oxygen depletion and the build up of carbon monoxide within the space being heated. This is also true of the fake fireplaces that burn gelled alcohol. Their design incorporates the use of burning two to four cans of the fuel at the same time. Of course this problem can be minimized and even eliminated by an opening of a window to allow for a fresh air flow, but the potential for this hazard remains and if the stove is being used as source of heat, having a window open even an inch will take away from the efficiency of the stove to heat a room. 
     Many of the existing stove designs are quite complicated and comprise a large number of parts requiring difficult and time consuming assembly. 
     SUMMARY OF THE INVENTION 
     The size of the stove of the present invention has been scaled down from most wood or gas burning stoves to reduce the weight to below 75 pounds and thus to make it light enough for any one person to pick up and carry or move. Because this stove does not require exterior venting, it can be used anywhere in the home and outside. The design makes the stove decorative as well as functional. That is, the stove will provide immediate heat by convection due to vent openings provided in a top grill plate, and long lasting, even, radiant heat due to the cast iron construction and shape of the stove body. The stove is designed to burn only one can of gelled alcohol at any one time, thus eliminating the concerns of oxygen depletion associated with an open flame in a closed room. By using gelled alcohol, this stove does not produce air pollutants and therefore does not have to be cleaned of any remaining soot and ash such as left behind from the burning of wood or coal. 
     It is therefore an object of the present invention to provide a stove having complete mobility and ease of use. 
     It is a further object of the invention to provide a stove that combines both the warmth and charm of a fireplace or a woodburning stove with the ambiance of burning candles. 
     It is a further object to provide a stove that can truly be portable, can be used where space is at a premium and is functional as well as decorative. 
     It is a further object to provide a stove which can be easily assembled with a minimum of parts, and, specifically, with a minimum of different parts. 
     Other objects and advantages of the present invention are described below with respect to an embodiment shown in the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front elevational view of a stove embodying the principles of the present invention. 
     FIG. 2 is a side elevational view, partially cut away, of the stove of FIG.  1 . 
     FIG. 3 is a plan view of the stove of FIG.  1 . 
     FIG. 4 is a plan view of a top grill for the stove of FIG.  1 . 
     FIG. 5 is a plan view of a support grill for the stove of FIG.  1 . 
     FIG. 6 is a bottom elevational view of the stove body of FIG.  1 . 
     FIG. 7 is a plan view of a metal sheet to be used in the stove of FIG.  1 . 
     FIG. 8 is a front perspective view of a support leg to be attached to the stove of FIG.  1 . 
     FIG. 9 is a rear perspective view of the support leg of FIG.  8 . 
     FIG. 10 is an exploded view of the door assembly for the stove of FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention provides an improved stove  20  as best shown in FIGS. 1 and 2 which is comprised of several individual parts: a main body portion  22 , a grill member  24  (FIG.  4 ), a shelf member  26  (FIG.  5 ), a door structure  28  (FIG.  10 ), a plurality of leg members  30  (FIGS.  8  &amp;  9 ), a bottom plate  32  (FIG. 7) and fasteners  34 . 
     The main body portion  22  is preferably formed as a single piece casting from cast iron. The main body portion has a base area  36  with a flat bottom wall  38 . In the base area  36  there are provided a plurality of air inlet vent openings  40  which provide for the inlet of combustion air to an interior  42  of the stove. Further, a clean out vent slot and enlarged vent opening  44  may be provided in the base area  36 , on at least one side thereof. The base area  36  may have a frusto pyramidal shape with four equal length sides, with one of the legs  30  being attached at the bottom wall  38  at a comer of each two adjacent sides. 
     Positioned above the frusto-pyramidal shaped base area  36  of the main body portion  22  is a cylindrically shaped transition area  46  and positioned above the transition area  46  is a pot belly shape area  48 . On one side of the pot belly area  48  is an opening  50  (FIG. 10) which preferably is rectangular in shape and which receives the door structure  28 . Positioned above the pot belly shaped area  48  is a short cylindrical chimney area  52  and above the chimney area is an inverted frusto-conical top area  54  having an enlarged flat top surface  56 . Within the top surface  56  is an opening  58 . The opening  58  has a diameter D 1  which is slightly greater than a diameter D 2  of the grill member  24  (FIG.  3 ). 
     As mentioned, the main body portion  22  is preferably formed of cast iron of a suitable thickness, such as ¼″, in order to enhance the ability of the stove to provide radiant heat, which is further enhanced by the pot belly shape of the stove. Such radiant heat provided through cast iron gives a longer lasting and more even heat than convection heat directly from burning fuel. 
     In order to assure portability of the stove of the present invention, the stove is sized such that the total weight of the stove will not exceed that which could be relatively easily moved by an individual. Thus, the fully assembled stove, with all components, is preferably sized and constructed such that it has a weight of less than about 75 pounds, and more preferably less than about 60 pounds. In one embodiment, in order to accommodate the weight requirements, the main body portion, from the top surface  56  to the bottom wall  38  has a dimension of about 19½″ with the top surface  56  being generally circular with a diameter D 3  of about 11½″. The bottom wall  38  is preferably about 11″ square. When the main body portion  22  is made of cast iron of an approximate thickness of ¼″, the weight of the main body portion would be about 49 pounds. 
     The grill member  24  (shown separately in FIG. 4) is also preferably formed of cast iron with a diameter of about 7″. When this grill member is made of cast iron with a thickness of about {fraction (3/16)}″, it has an approximate weight of 1.75 pounds. 
     The opening  58  in the top wall  56  preferably has a diameter of about 7⅛″ so that it will easily accommodate the grill member  24 . A segmented ledge  60  is provided around the circumference of the opening  58  with opposed slots  62  providing areas where the full diameter D 1  of the opening  58  is unrestricted. The ledge  60  has an internal diameter D 4  preferably of about 6½″ so that it is sized less than the diameter D 2  of the grill member  24 . Thus, the grill member  24  will be supported on the ledge  60  with a top surface of the grill member  24  being flush with the top surface  56  of the main body portion  22 . 
     The grill member  24  is provided with a plurality of vent openings  64  to allow heated air and exhaust gases to exit from the interior  42  of the stove  20 . Also, the grill member  24  is provided with a tab  66  projecting from a bottom surface thereof which can be positioned within one of the slots  62  to prevent rotation of the grill member on the ledge  60 . 
     The shelf member  26  (shown separately in FIG. 5) is preferably formed identical to the grill member  24  in shape, size and material except that it does not include the tab  66 . Such an arrangement allows for reduced manufacturing costs. 
     In the interior  42  of the body portion  22 , and specifically within the cylindrical transition area  46 , there is provided an internal ledge  68  for receiving and supporting the shelf member  26 . Thus, an internal open diameter D 5  (see FIG. 6) of the cylindrical portion  46  is sized slightly greater than a diameter D 6  of the shelf member  26  so that the shelf member  26  can be received within the interior of the cylindrical portion  46 . It is also therefore preferred that an internal diameter D 7  of the ledge  68  is dimensioned smaller than the diameter D 6  of the shelf member  26  so as to provide vertical support for the shelf member. 
     The shelf member  26  could also have a larger diameter than the diameter D 5  of the cylindrical portion, and would thereby rest on the interior surface of the pot belly shaped portion  48 . However, it is preferred to provide the ledge  68  so that the shelf member  26  will always assume a horizontal, level orientation. 
     Of course it is also possible to form the transition area  46  and/or the shelf member  26  in a shape other than circular, the main consideration being that there be provided horizontal support for the shelf member  26  within the interior of the main body portion  22 . 
     As with the grill member  24 , the shelf member  26  is provided with a plurality of air vents  70  which permit the passage of air flowing in through the air inlets  40 , as shown by arrows  72  to flow through the shelf member  26  as indicated by arrow  74  to provide combustion air to fuel located in a fuel container  76  which is supported on the shelf member  26 . The products of combustion and heated air will continue to rise within the interior  42  of the main body portion  22  by convection, in the process heating the main body portion  22 , and will continue upward through the outlet vents  64  in the grill member  24 . 
     Although the grill member is shown as being circular in shape, it also could be formed of different geometric shapes. However, by providing the grill member  24  and shelf member  26  with the same size and shape, and by providing the opposed slots  62  in the ledge  60  at opening  58 , it is possible to insert the shelf member  26  by holding it vertical and passing it through the slots  62 , and then rotating the shelf member to a horizontal orientation to place it on the lower ledge  68 . Alternatively, the opening  50  in the side of the pot belly portion  48  can be sized to accommodate the shelf member  26  therethrough, either horizontally, vertically or diagonally. 
     As seen in FIG. 6, the main body portion  22  has an irregularly, but symmetrically shaped opening  82  formed in the bottom wall  38  thereof. The shape of the opening  82  is substantially square, however there are four laterally projecting fingers  84  which define slot areas  86  in each corner of the bottom. A square recess  88  defined by an outer perimeter rim  89  surrounds the opening  82  for receiving the bottom plate  32 . The bottom plate  32 , which can be formed of a lightweight non-flammable material, such as aluminum, has an opening  90  formed near each corner thereof which aligns with the slot areas  86  in the main body portion. 
     The leg members  30  are shown in isolated detail in FIGS. 8 and 9 where it is seen that they are formed of two vertical walls  92 ,  94  joined along one edge  93  and arranged generally perpendicular to one another to form a horizontal L cross section. At a top end there is a horizontal wall  96  joining the two vertical walls  92 ,  94  and having a generally triangular shape which is offset inwardly at  95  from the two vertical walls  92 ,  94 , and elevated by a short vertical wall  97  above a top end of vertical walls  92 ,  94 . A slot  98  is formed in the top wall  96 . 
     In the preferred arrangement as shown in the drawings, the legs  30  can be attached to the main body portion  22  by fasteners  34 , such as a threaded bolts. Preferably, the threaded bolt has a large head  99  which is captured against rotation by interior surfaces of the sidewalls of the base member  36  such that a separate tool is not required to be used to hold the bolt against rotation during assembly. A shank portion of the bolt extends down through the slot area  86  of the bottom wall  38 , through the opening  90  in the bottom plate  32 . A washer, having a diameter greater than the width of the slot  98  in the leg  30  is placed over the shank of the fastener and a nut is loosely threaded onto the shank to provide a loose assembly of the fastener. The leg  30  is then slipped onto the bolt shank, by means of the slot  98 , and the leg is seated with the top wall  96  abutted against the bottom plate  32  and the offset  95  and vertical wall  97  abutted against the outer perimeter rim  89  of the bottom wall  38 , so that the leg itself is interlocked with the main body portion  22  against rotation. The nut is then tightened on the shank to provide a clamping action between the head and the nut, capturing the top wall  96  of the leg, the bottom plate  32  and the finger  84  of the main body portion  22  in an assembled relationship. The vent openings  40  in the base area  36  provide access to the fastener  36  to assist in assembly and disassembly of the leg members. Alternatively, the fasteners can be accessed through the open interior  42  of the main body portion  22  either through the door opening  50  or the top opening  58 . 
     In the preferred embodiment, the legs may also be formed of cast iron, with all four legs being identical in shape and size and having a vertical dimension of approximately 6″ and a thickness of about {fraction (3/16)}″ to ¼″, so that each leg would have an approximate weight of 0.8 pounds. 
     The door structure  28  is shown in greater detail in FIG. 10 where it is seen that it is comprised of two identical door members  100 . The door members  100  are provided with hinge pins  102  projecting from a top and bottom edge at one side of the door and with a plurality of openings  104 , shown in the form of vertical slots through the door. The doors are also provided with a handle tab  106  projecting from a front surface thereof on a side opposite the side having the hinge pins  102 . 
     The door opening  50  is provided with four recess areas or pockets  108  at each comer to receive the hinge pins  102  and brass bearings  109  of the door members  100 . The door opening is also provided with a lip  110  surrounding, but recessed within the opening  50  to provide an abutment stop for a back side of the doors. The opening  50  is sized vertically and horizontally to receive the vertical and horizontal width of the two door members  100  placed side-by-side and to provide some clearance to accommodate expansion and contraction. The bearings  109  are placed onto the hinge pins  102  and then the door members  100  are placed within the door opening  50  and against the lip  110  so that the front face of the door members  100  will be essentially flush with a front face  112  of an area surrounding the door opening  50 . The bearings  109  preferably have an internal diameter greater than an outer diameter of the hinge pins and an outer diameter slightly greater than the recesses  108  so that the bearings will need to be press fit into the recesses which will hold them securely in place, yet the hinge pins will be able to easily rotate within the bearings. Wedge members  114  are hammered into the recesses  108  which already contain the hinge pins  102  and bearings  109  to lock the hinge pins and bearings within the recesses. In this manner, the door members  102  will therefore be securely retained within the opening  50 , yet free to pivot between open and closed positions. 
     Although the embodiment illustrated provides two identical doors which open at the center, a single door pivoted at one side, the top or the bottom could also be provided. 
     The openings  104  provide visual access into the interior  42  of the pot belly portion  48 , and in particular to the area of the fuel container  76 , so that the burning condition of the fuel can be visually checked. This also provides the visual aesthetics of a burning flame. 
     It is preferred that the door opening  50  be tilted from vertical, such as by an angle A (FIG. 2) of about 11° whereby a top end of the door opening is positioned rearward of a bottom end. In this manner, the door members  100  will be held in a closed position by gravity when they are flush with the surrounding surface  112 . Such an angle also provides a more direct line of sight toward the fuel container  76 . 
     In the preferred embodiment, the door opening generally has a horizontal dimension of about 6½″ and a vertical dimension of about 5″, with each door having a vertical dimension of about 5″ and a horizontal dimension of about 3¼″, with appropriate clearances being provided. Thus, when the doors are formed of cast iron, they each would have a weight of approximately 0.37 pounds. 
     Thus, the assembled weight of the stove, comprising the main body portion  22 , the grill  24 , the shelf  26 , the door structure  28 , the four legs  30 , the bottom shelf  32  and fastening members  34  will be less than about 75 pounds and, in the particular embodiment illustrated and described, could be less than about 60 pounds. Thus, the size, shape and weight of such a stove render it portable and allow for its relatively easy movement by a single person. Nevertheless, its construction including its shape and the use of cast iron, allows the stove to provide both fast convective heat as well as long lasting and even radiant heat and also permits the viewing of the burning flame of the fuel, while enclosing the flame and fuel so as to substantially reduce any risk of uncontrolled fire. The size, shape and construction of the stove render it quite stable and combined with the weight of the stove substantially prevents any accidental tipping of the stove through bumping or other similar actions. The relatively small number of parts to be assembled and the duplication of some parts renders the stove economical and easy to manufacture and assemble. The stove can also be opened and disassembled easily for cleaning, storing or shipping. 
     Although a particular embodiment of the stove is shown and described, it can be appreciated that the present invention could be arranged with other specific configurations and arrangements while still keeping within the scope of the claims set forth below. 
     As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. It should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.