Title of Invention

METALLIC WICK FOR LIGHTING AND HEATING AND SYSTEMS FOR LIGHTING AND HEATING CONTAINING THE SAME

Abstract

This invention relates to a metallic wick for lighting and heating. The wick is made by gravitation casting of a metal or metal alloy followed by sintering. Diffusion of atoms during this step produces micro-pores through the cast body. Micro pores transport fuel from its source to the point of ignition. Metallic wicks form a part of the heating or lighting system and need not be replaced. This invention also includes a system for heating or lighting provided with at least one metallic wick disclosed herein above.

Full Text

This invention relates to a metallic wick for lighting and heating. The invention also includes systems for lighting and heating containing said wicks. Wick is a small strip or thread that feeds oil to be inflamed in heating and lighting systems, like lamps, candles and stoves. Conventionally, wicks are made of soft cotton or cotton fibre rolled or twisted, which facilitates burning of the fuel. Light and heavy hydrocarbon fuels provide heat and light on ignition of the wick to which fuel is supplied. In this process, the wick also gets burnt out. Burning fuels other than hydrocarbon fuels such as animal and vegetable oils and fats for i lighting and heating also uses up the medium, ie. the wick which transports the fuel to the point of ignition. Periodic replacement of wicks therefore becomes a necessity in such applications and hence the need for developing a wick which will be a permanent feature of the heating or lighting system. It is an object of this invention to develop a metallic wick which does not burn out during the process of ignition and which forms a part of the heating and lighting systems. We have found that a wick made from compacted metals or alloys forms a viable alternative to wicks hitherto known in the art. Wicks according to our invention need not be replaced periodically. In the event of clogging of pores, the wick may be cleaned or brushed preferably with a metallic brush with strong bristles to clean the clogged pores and then reinstalled in the heating or lighting system. Wicks according to our invention is suitable not only for oil lamps that provide lighting but can also be used in stoves for heating purposes. The novel wick is an article having immense utility value as fuel consumption is reduced and wastage avoided. By avoiding or eliminating periodic replacement, it helps save labour and time. The wick according to our invention can be made by known powder metallurgy techniques. A mould, preferably a graphite mould, having a cylindrical cavity is selected and the selected metal powder is packed therein without application of external pressure. | The mould and its contents are then sintered and cooled. The wick is then removed from the mould, cleaned, and if desired, cut to the required size. i | ■ While compacting the metal according to the powder metallurgical processes, atom movement termed diffusion will start above the melting point of the metal and continue till solidification. It is necessary to limit the radial size of the cast to a thickness of 10 mm to 30 mm to obtain optimum functioning of the wick. The reason for this limitation is that maximum porosity of the cast member is obtained when the radial size is limited to 10mm to 30 mm. Homogeneous permeability may not be obtained if a large mass is cast by increasing the surface temperature during casting and sintering operation. Though sintering and diffusion of atoms start from 500°C onwards, effective sintering starts above 600°C due to uniform atom diffusion. The minimum porosity of the wick must be 5 u and the maximum 500 u. Copper and alloys of copper are found to be ideal for making wicks according to our invention, as they are resistant to corrosion and oxidation on exposure, though use of other metals and their alloys are not excluded from the scope of this invention. Mesh size of the metal powder to be compacted for wick formation is not critical and may be varied subject to availability from the raw material suppliers. Copper and bronze of 200 mesh size have been successfully cast by us for producing wicks with maximum and effective functioning. Casting is done without application of external pressure and during sintering micro pores are produced throughout the casting. These pores provide capillary action for transporting the fuel from the container to the point of ignition. Though mould made from any conventional material can be used for casting the wick, graphite j mould is preferred as it is self lubricating. The metallic wick for lighting and heating according to this invention comprises a cast metal or metal alloy body having a plurality of microspores thereon made by gravitational casting of 1 " i the sail metal or alloy and sintering the same till atomic diffusion is maximised to create micro-pores thereon. The wick may be rod shaped and one end thereof may be tapered to a point. The micro pores providing capillary action jbrings fuel in a container to the ignition point where the same can be burned and this process is maintained till the flame is extinguished. As stated earlier, only frequent cleaning is required for maintaining this capillary action. The following example illustrates the process of making the wick without limiting the same. Bronze powder is packed in a graphite mould cavity without application of external pressure. The mould has a cylindrical cavity. Bronze powder of 200 mesh is used in this example and is allowed to settle in the mould by gravitational force. The mould and its contents are heated in a furnace to about 600°C for 30 minutes and then allowed to cool. The cast wick body is then removed from the mould and found to have a plurality of micro pores extending through out. , The wick according to this invention may be fixed in a conventional oil lamp with metallic screws such that a portion of it is located within the tank container having fuel. The opposite end of the wick is exposed to the atmosphere and may be lit. The fuel in the fuel tank migrates to the top through the nicro pores and burns. This invention also includes a system for lighting or heating provided with at least one metallic wick having micro t pores thereon made by gravitational casting of a metal or metal alloy and sintering the same till atomic diffusion is maximised to provide micro-pores thereon. Numerous alterations and modifications may be devised by persons skilled in the art to make a wick described herein above. The above description and the appended claims do not exclude these obvious alterations and modifications. We Claim: 1. A metallic wick for lighting and heating comprising a cast metal or metal alloy body having a plurality of micro pores thereon made by gravitational casting of the said metal or metal alloy and sintering the same till atomic diffusion is maximised to create micro-pores thereon. 2. The metallic wick as claimed in claim 1, wherein the metal ! ! "or the alloy is copper and bronze respectively. |3. The metallic wick as claimed in claims 1 and 2, wherein r copper or bronze of mesh size 200 is cast to obtain a porosity "i ranging from 5 u to 500 u. 4. The metallic wick as claimed in any of the preceding claims i wherein the radial size of then wick is from 10 mm to 30 mm. ■ i ■ 5. The metallic wick as claimed in any of the preceding claims wherein the casting is carried out in graphite moulds. 6. The metallic wick as claimed in any of the preceding claims wherein sintering is effected by heating the cast to 600°C for 30 minutes and is then cooled. 7. The metallic wick as claimed in any of the preceding claims wherein the wick is rod shaped, one end of which is tapered. . 8. A system for lighting or heating provided with at least one metallic wick having micro pores thereon made by gravitational casting or a metal or metal alloy and sintering the same till atomic diffusion is maximised to provide micro-pores thereon. 9. A metallic wick for lighting and heating substantially as herein described. 10. A system for lighting and heating substantially as herein described.

Documents:

2587-mas-1997 abstract-duplicate.pdf

2587-mas-1997 abstract.pdf

2587-mas-1997 claims-duplicate.pdf

2587-mas-1997 claims.pdf

2587-mas-1997 correspondence-others.pdf

2587-mas-1997 correspondence-po.pdf

2587-mas-1997 description (complete)-duplicate.pdf

2587-mas-1997 description (complete).pdf

2587-mas-1997 form-1.pdf

2587-mas-1997 form-19.pdf

2587-mas-1997 form-26.pdf