Title of Invention

TROLLEY FOR SUNLIGHT CUM SMOKE DRYING OF NATURAL RUBBER SHEETS

Abstract

A device for drying rubber sheets is disclosed. The device comprises a main frame, at least one or more layers slidably mounted on a on said main frame, each of said layers consisting of a frame work and one or more beroties mounted between the framework of each layer on which the rubber sheets can be hung to dry them, said layers being arranged with respect to each other in such a manner that no layer overlaps with another layer. The device allows the sheets to be subjected to adequate aeration and sunlight for drying. The device can also be collapsed and taken into a smoke chamber for drying in a conventional manner.

Full Text

Field of the invention The present invention relates to a device for drying sheet rubber materials. More particularly, the present invention relates to a novel device for drying several sheets of rubber both using ordinary sunlight and the usual smoke drying method. The present invention is particularly useful to owners of small rubber plantations as it is cost effective and easy to use, ultimately resulting in the production of better grade sheet rubber. Background of the invention Natural rubber sifter being extracted from the trees and treated with various chemicals is processed into different marketable forms such as ribbed smoked sheets, solid blocks, crepes and concentrated latex. Ribbed smoked sheet, which is one of the most popular form of marketed rubber in India, is graded by visual examination for the presence of dirt, dust, tackiness, fungus, colored spots, blisters, bubbles etc. In the Indian scenario, majority of the rubber produce comes from small plantations with an area less than a hectare. Latex collected from such small holdings is processed mainly into ribbed smoked sheets, while the field coagulum is converted in to either block rubber or low grade crepe. One of the major drawbacks of the rubber processed from these small holdings, is the low quality of the sheet rubber being produced. Lack of consistency in the quality of the rubber is also an area of concern. Despite diligent efforts by the Rubber Board to organize processing of small holders' latex, bulk of the latex produced by the small holdings is still processed by the growers themselves into poor quality rubber sheets, due to socio-economic hindrances. Although, block rubber conforming to technical specifications has been claimed to be superior to conventional forms of processed rubber, such claim does not have adequate justification, especially considering the price of block rubber, which is considerably higher than sheet rubber. Moreover, rubber good manufactures are today, preferring good quality rubber sheets to block rubber. One of the major causes for low quality of sheet rubber produced in these small holdings is the unscientific drying methods employed. Very often the sheets are dried in open sun, laying them on the bare ground, on the bare roof of the buildings, on compound walls and even on public roads, causing accumulation of dirt, overheating and incomplete drying. This causes mould growth and surface contamination, thereby reducing the quality of the sheet rubber. The conventional method of smoke drying is not practiced widely mainly on account of the high capital requirement and increasing cost of firewood. Since sun drying is the cheapest method, it is obviously most popular. However, the one danger in using this method is that overexposure of sneets to sunlight could result in the deterioration their quality. Moreover, practice of drying in the sun in the open often causes a lot of inconvenience as the sheets have to be moved from one place to another depending upon the availability and the direction of the direct sunlight and shifting the sheets to a storage space during rains and at night. It has now been well recognised that the quality of the sheets directly depend upon the manner in which the sheets are cleaned and dried. Towards this end, the applicants' own co-pending application No filed on June 21, 2001 describes and claims a novel device for a more scientific cleaning of low quality sheet rubber. The present invention, on the other hand, is directed to a device for drying sheet rubber. Objects of the invention It an object of the present invention is to provide a device for drying rubber sheets. It is another object of the present invention to provide a device, which is capable of being used to dry rubber sheets both under the sunlight and by using the conventional smoke-drying method. It is another object of the present invention to provide a device for the drying of rubber sheets, which will reduce the processing cost of the plantation owner. It is yet another object of the present invention to provide a device for the drying of sheets, which is mobile in order to facilitate the movement of sheets from one place to another. These and other objects of the invention are achieved by the novel portable and collapsible device of the present invention which essentially includes one or more layers slidably mounted on a on a frames with each layer including beroties on which the rubber sheets can be hung to dry them, said layers being arranged in such a manner that no layer overlaps with another layer. In a preferred embodiment, the device is in the form of a trolley, preferably equipped with swivel caster wheels for easy maneuverability and portability. It essentially consists of one or more sliding layers, preferably, four in number, at least a guard layer and a top layer. The top layer is preferably mounted on a frame, preferably, a mild steel angle framework. The sliding layers are mounted in such a manner that they are capable of being drawn out in four different directions. In a preferred embodiment, the main frame and all the layers of the trolley are made of mild steel angles of pre-determined size. Preferably, all the layers, except the guard layer, are equidistant from each other. In another preferrea embodiment, tne distance between the guard layer and the nearest sliding layer is greater than the distance between two adjacent sliding layers. When the trolley is brought out in the sun, the sliding layer are coasted out and they get drawn in four different directions, thereby preventing any layer, including the top layer, from overlapping any other lower layer. This ensures, that, neither shadow nor dripping water from the sheets in the top layer fall on the sheets hanging in the bottom layers. This leads to better aeration, and therefore, faster, better and more uniform drying. During the night, the sliding layers are pushed back inside the trolley and arranged one over the other and the trolley is easily rolled into the smoke chamber. This guarantees that there is continues drying of sheets even during night or rain. The sliding and the top fixed layers are provided with slots to insert therein a plurality of beroties on which the rubber sheets can be hung. The slots are spaced apart from each other to ensure that the beroties and therefore, the hanging rubber sheets are also spaced apart from each other. This will not only avoid crowding of rubber sheets with resultant uneven drying, mould growth and foul smell, but actually ensures healthy aeration between the sheets and better and faster drying. In a prefererd embodiment with four sliding layers, there will ideally be 15 beroties in each layer which means that the trolley can carry 150 sheets of 500 gram dry weight at one time, a total of 75 kgs. a weight which would be easy to roU around. However, as will be apparent to a person skilled in the art, the present invention is not restricted by the size of the trolley, the number of sliding layers or number of beroties. The sliding layers may have inverted guide rails which enables them to slide effortlessly over rollers mounted on opposing rails. Alternatively, the four comers of each sliding layer may be equipped with at least one roller to expedite the drawing out of the layer. The sliding layers when drawn out may be supported on iron rods to keep up the level, thereby maintaining the over all balance of the trolley. The rods are connected to the sliding layer through a slot on the frame of the layer. The guard layer is intended for collecting the sheets in case they accidentally fall off and prevent the sheets from catching fire. Preferably, the guard layer may be in the form of a wire mesh. The trolley is equipped with swivel casters, which are preferably bolted or welded or attached by any conventional means to the frame of the trolley at the four comers. This helps in the movement of the trolley in and out of the smoke house, while carrying the sheets. Detailed description of the invention The present invention will now be explained in greater detail with reference to the accompanying drawings wherein:. Fig. 1 is the sectional view of the device of the present invention; Fig. 2 shows the front elevation of the device of the present invention Fig. 3 shows the complete device of the invention in use in sunlight. Referring to Fig. 1, the device is generally indicated by the reference numeral 1. The device is in the form of a trolley. It comprises of a frame 2 on which are slidably mounted four layers 4A, 4B, 4C and 4D. The top layer 5 and bottom layer 3 are fixedly mounted on the top of the frame . The layer 3 acts as a guard layer capturing any sheet rubber, which may accidentally fall. Each of the slide layer has frame 4F which is provided with a plurality of slots. A plurality of beroties 10 (fig. 3) are connected between the slots from, which the sheets 9 hang. Figure 2 shows a front elevation of the device of the present invention with the layers 4C and 4D drawn out. Layers 4A and 4B if drawn out would be above and below the plane of the paper. As will be apparent, the layers when drawn out are in totally different directions that none of them overlaps with the other. For lending stability to the device and for maintaining the layers in place, each of the sliding layers may be supported by support rod 8 connected to the main frame 2 and connectable to the frame of the sliding layer in question. As will be seen from Fig. 3, all the open sliding layers 4A, 4B, 4C and 4D are away from each other to prevent shadow or dripping water from a top layer from falling on a bottom layer. The lowermost layer, which is the guard layer 3 is in the form of a wire mesh to capture any sheet, which may accidentally fall. All other layers, including the fixed top layer 5 have a plurality of beroties 10 on which are hung sheets 9 for drying. The sheets 9 are spaced apart from each other so that each sheet gets adequate air and sun. In the evenings, the slidable layers are pushed back into the frame and the trolley is moved to a smoke chamber where the sheets may be subjected to conventional smoke drying, thus ensuring that there is no discontinuity in drying. It alternative embodiments, there may be more than four slidable layers and a plurality of beroties in each layer. As the trolley is designed for maximum use of sunlight for drying sheet rubber with minimum handling of sheets, the cost of drying as well as the surface contamination of the sheet is reduced. Since the trolley envisages the use of both sunlight and smoke-drying method together, the consumption of fuel is substantially reduced as partial drying is done under the sunlight. An over all saving in the fire wood, up to 55-66%during summers and 20% during the rainy season can be achieved using this trolley. It must be borne in mind that the present invention has been illustrated above with reference to the most preferred embodiment and other modification and embodiments of the invention are possible without departing from the spirit and scope of the invention. We claim: 1. A device for drying rubber sheets which comprises a main frame at least one or more layers slidably mounted on a on said main frame, each of said layers consisting of a frame work and one or more beroties mounted between the framework of each layer on which the rubber sheets can be hung to dry them, said layers being arranged with respect to each other in such a manner that no layer overlaps with another layer. 2. A device as claimed in claim 1 wherein at least four sliding layers are connected to said main frame. 3. A device as claimed in claim 1 or 2 wherein at least a guard layer is mounted on said main framework, said guard layer being located below the lowermost sliding layer to capture any rubber sheet which may accidentally fall. 4. A device as claimed in claim 3 wherein said guard layer is in the fonn of a wire mesh. 5. A device as claimed in any preceding claim wherein a fixed layer is mounted on the main frame, above the topmost slidable layer. 6. A device as claimed in any preceding claim wherein the main frame is of a mild steel angle framework. 7. A device as claimed in any preceding claim, wherein all the layers are made of mild steel angles. 8. A device as claimed in any preceding claim wherein all the layers, except the guard layer, are equidistant from each other, 9. A device as claimed in claim 8 wherein the distance between the guard layer and the nearest sliding layer is greater than the distance between two adjacent sliding layers. 10. A device as claimed in any preceding claim wherein said sliding and the top fixed layers are provided with slots between which, said a plurality of beroties connected. 11. A device as claimed in any preceding claim wherein said sliding layers are provided with guide rails for enabling them to slide over corresponding rollers mounted on opposing rails on said main frame. 12. A device as claimed in any preceding claim 1 to 10, wherein the four comers of each sliding layer is e equipped with at least one roller to allow said layer to move over guide rails on said main frame. 13. A device as claimed in any preceding claim wherein at least a support rod is moveably connected to said main frame, said support rod being capable of engaging a slot on the frame of said sliding layers and hold it in its place while said sliding layer is in a drawn position. 14. A device as claimed in any preceding claim wherein said device is in the form of a trolley equipped with swivel casters, which are preferably bolted or welded or attached by any conventional means to the frame of the trolley at the four comers. 15. A device for drying rubber sheets substantially as described herein with reference to the accompanying drawings.

Documents:

503-mas-2001-abstract.pdf

503-mas-2001-claims filed.pdf

503-mas-2001-claims granted.pdf

503-mas-2001-correspondnece-others.pdf

503-mas-2001-correspondnece-po.pdf

503-mas-2001-description(complete)filed.pdf

503-mas-2001-description(complete)granted.pdf

503-mas-2001-drawings.pdf

503-mas-2001-form 1.pdf

503-mas-2001-form 19.pdf

503-mas-2001-form 26.pdf