Background to the invention The applicant is aware of several camping and rural community household stoves, which burn a liquid or gas fuel. The liquid burning stoves such as paraffin burning stoves usually need to employ a pre heating system to cause the fuel to vaporise and to ensure sufficient mixture with air in order to obtain a warm flame for cooking. The pre heating, or primus type stoves are expensive, limited to cooking and not refillable while in use since the liquid is pressurised. It is an object of this invention to provide a modular heating apparatus which is cost effective, can be used for different household heating purposes, is easy and safe to operate, and which can be refuelled during use.

The invention will be particularly suited for use by people who live in remote or rural areas with no available electricity.

Summary of the invention According to a first aspect of the invention, there is provided a fuel burner for a modular heating apparatus, which includes a hollow body, the body having a floor and an outer wall which extends upwardly from the floor, a fuel inlet defined in the outer wall, and an airflow conduit which extends upwardly from an opening in the floor such that a reservoir is defined between the outer wall and a wall of the airflow conduit.

The upwardly extending airflow conduit may extend centrally upwardly from the floor such that the reservoir surrounds the upwardly extending airflow conduit.

The burner may further include a second airflow conduit, which extends sideways from an opening in the outer wall. The upwardly extending airflow conduit may extend past the upper level of the opening in the outer wall. It will be appreciated that the upwardly extending airflow conduit provides the majority of airflow for combustion of the fuel during high fuel levels in the reservoir, while the second airflow conduit provides air for substantially complete combustion of fuel in the reservoir during low levels of fuel in the reservoir. The burner may also include an adjustment means for adjusting the size of the opening in the floor such that the air flow rate may be operatively adjustable. It will be appreciated that the heat and the rate of fuel combustion may be regulated by means of the adjustment means.

According to a further aspect of the invention, there is provided a resiliently flexible fuel container for a modular heating apparatus, the container having an inlet opening and a fuel outlet.

The inlet opening of the fuel container may be openably closable. It will be appreciated that this allows a user of the apparatus, when the inlet is closed to force fuel, which may be in the form of a viscous liquid or a gel, from the container through the conduit to the burner as desired by means of squeezing the container. Conversely, if desired, the user may displace air from the container by squeezing the container, close the inlet to form a low pressure and allow the resilient container to return to its natural shape thereby sucking excess fuel from the burner.

The modular heating apparatus may further include a tube for conveying fuel, which extends between the fuel outlet of the fuel container and the fuel inlet of the fuel burner.

The tube for conveying fuel may be provided with a valve for facilitating flow of fuel into and/or out of the reservoir. It will be appreciated that the valve may also prevent a flash or flame to reach the container, thereby preventing a possible fire hazard.

According to a further aspect of the invention, there is provided a heater for a modular heating apparatus. The heater may be an open ended elongate hollow extension part, which is mountable to the hollow body of the burner to extend the burner upwardly. It will be appreciated that such an extended hollow body will be heated in use by the burner and can be used as a heater for heating a cold atmosphere in a room. It will also be appreciated that an item may also be heated at the open end of the heater if desired.

According to an even further aspect of the invention, there is provided a housing for housing the burner. The housing may include a detachable base and a wall extending upwardly from the base for enclosing the burner. An upper end of the housing may be open and configured to receive an article to be heated. The article to be heated may be a plate, a recessed plate, pot, and the like. The wall of the housing may have openings through which the tube for conveying fuel and the second airflow conduit extend.

The base of the housing may have an opening defined therein, which corresponds to the opening in the floor of the body of the burner.

Instead of the opening in the floor of the hollow body of the burner being adjustable, the opening in the base may be provided with an adjusting means such that the air flow rate may be operatively adjustable. The base may have downwardly extending protrusions to raise the base from a support surface, such as the work surface of a kitchen table, to allow airflow towards the openings.

The fuel burner may include a heat distribution part in the form of a perforated open ended hollow extension part, which is mountable to the hollow body to extend the hollow body of the burner upwardly up to the upper

end of the housing. It will be appreciated that the extended hollow body facilitates lateral and even distribution of the heat of a flame in the burner.

The wall of the housing extending upwardly from the base for enclosing the burner may comprise an inner and outer wall. The walls may be sealingly attached at the upper end and lower end of the housing such that a room is defined about the housing between the walls. The outer wall of the housing may be provided with an inlet and outlet such that a fluid such as water may be passed through the room and heated by the burner.

All the parts of the apparatus that gets exposed to heat, in use, may be metal, preferably of an aluminium containing alloy, aluminised metal or tin alloy. It will be appreciated that certain aluminium containing alloys harden during heating and cooling cycles.

According to another aspect of the invention, there is provided a fuel containing refill pack for a modular heating apparatus as described above.

The refill packs may be in the form of sealed sachets and the apparatus may then include a nozzle, which includes a body having a passage defined through it, the passage extending from one end to another. One end of the body may be provided with a sharp edge about the opening of the passage for piercing the sachet and a collar such that the sachet may be sealingly tied to the nozzle. The other end of the nozzle may be configured to fit onto the inlet of the fuel container such that the sachet is placed in fluid communication with the container. It will be appreciated that this invention allows a user to refuel the apparatus while is in use.

The apparatus will be understood to modular in the sense that some components are interchangeable, the apparatus can be expanded and further burners and accessories added or removed as required by a user.

Detailed description of the invention

The invention is now described by way of example with reference to the accompanying drawings.

In the drawings: Figure 1 shows a three dimensional view of a modular heating apparatus, in accordance with the invention; Figure 2 shows an exploded three-dimensional view of the apparatus; Figure 3 shows a sectional side view of the apparatus; Figure 4 shows a sectional side view of the apparatus; Figure 5 shows a side view of a nozzle, in accordance with the invention; Figure 6 the refilling of the fuel container in accordance with the invention; Figure 7 shows a three dimensional view of a further embodiment of a burner, in accordance with the invention; Figure 8 shows a sectional side view of a base, in accordance with the invention; and Figure 9 shows a plan view of the base.

In the drawings, a modular heating apparatus is generally indicated by reference numeral 10.

The modular heating apparatus 10 includes a fuel burner 12, which includes a hollow body 14, the body 14 having a floor 16 and an outer wall 18, which extends upwardly from the floor 16. A fuel inlet 20 is defined in the outer wall 18 and an airflow conduit 22 extends upwardly from an opening 23 in the floor such that a reservoir 24 is defined between the outer wall 18 and a wall 26 of the airflow conduit 22. The upwardly extending airflow conduit 22 extends centrally upwardly from the floor 16 such that the reservoir 24 surrounds the upwardly extending airflow conduit 22. The burner 12 further includes a second airflow conduit 28, which extends sideways from an opening 29 in the outer wall 18. The upwardly extending airflow conduit 22 extends past the upper level of the opening 29 in the outer wall 18.

The apparatus 10 further includes a resiliently flexible fuel container 32 having an inlet opening 34 and a fuel outlet 36. The inlet opening 34 of the fuel container is openably closable.

The modular heating apparatus 10 further includes a tube 38 for conveying fuel, which extends between the fuel 36 outlet of the fuel container 32 and the fuel inlet 20 of the fuel burner 12. The tube 38 for conveying fuel is provided with an openably closable on way valve (not shown) for facilitating flow of fuel into and/or out of the reservoir 24.

The apparatus 10 further includes a heater 42. The heater is in the form of an open ended elongate hollow extension part, which is mountable to the hollow body 14 of the burner 12 to extend the burner 12 upwardly.

The apparatus 10 further includes a housing 44 for housing the burner 12. The housing 44 includes a detachable base 46 and a wall 48 extending upwardly from the base 46 to enclose the burner 12. An upper end 50 of the housing is open and configured to receive an article 52 to be heated. The article 50, in this example, is a recessed plate. The recess of the plate can therefore be filled with water and used as a steaming hotplate. The applicant has found that the heat is most intense if an item is heated directly on top of the housing 44 and that a lower intensity can be obtained by using the recessed plate with its recess facing downward. The wall 48 of the housing has openings through which the tube 38 for conveying fuel and the second airflow conduit 28 extend.

As shown in figures 8 and 9, the base 46 of the housing 44 has an opening 56 defined therein, which corresponds to the opening in the floor of the body 14 of the burner 12. The opening 56 in the base 46 is provided with a pivotally mounted adjusting means 58 such that the size of the opening 56 and thus the air flow rate through the openings is operatively adjustable by pivoting the adjustment means 58 about a pivot point 47. The base has downwardly extending protrusions 57 to raise the base 46 from a support

surface, such as the work surface of a kitchen table, to allow airflow towards the openings. The housing 44 is also provided with a support 59 for supporting the heater 42. The applicant has found that a bigger opening produces a colder, longer burning flame and a smaller opening a hotter faster burning flame while a diameter of about 16mm is a good balance between heat and fuel consumption. Conveniently, the apparatus 10 is also provided with a metal pin 63 for supporting the heater 42. The pin 63 can also be used to clean the apparatus 10 and to light the burner 12 by dipping the pin 63 in the fuel and lighting the dipped pin 63.

The fuel burner 12 includes a heat distribution part 60 in the form of a perforated open ended hollow extension part, which is mountable to the hollow body 14 to extend the hollow body 14 of the burner 14 upwardly up to just below the upper end 50 of the housing 44.

In one embodiment of the invention, the wall 48 of the housing extending upwardly from the base 46 for enclosing the burner comprises an inner 62 and outer wall 64. The walls 62 and 64 are sealingly attached at the upper end 50 and lower 66 end of the housing 44 such that a room 67 is defined about the housing 44 between the walls 62 and 64. The outer wall 64 of the housing is provided with an inlet 68 and an outlet 70 such that a fluid such as water can passed through the room 67 and heated by the burner 12.

The apparatus 10 also include fuel containing refill packs 72. The refill packs 72 is in the form of sealed sachets and the apparatus 10 then includes a nozzle 74. The nozzle 74 includes a body 76 having a passage 78 defined through it, the passage 78 extending from one end to another. One end 81 of the body 76 is provided with a sharp edge 80 at the opening of the passage for piercing the sachet and a collar 82 such that the sachet may be sealingly tied to the nozzle 74 with a cable tie or elastic. The other end 84 of the nozzle 74 is configured to fit onto and mate exclusively with the inlet 34 of the fuel container 32 and to open a one way valve located in the inlet 34 such that the sachet is placed in fluid communication with the container 32, while preventing other substances from being erroneously charged into the container 32.

In another embodiment, as shown in Figure 7, the burner 12 may be provided with two fuel inlets 20 and two second airflow conduits 28. The second airflow conduits 28 is extended upwards to allow a larger quantity of fuel in the reservoir 24. The burner is also provided with a heat distribution part 60 and a frusto conical flame or heat deflector 86 in order to maximise the heating effectiveness of the apparatus 10.