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Home | Alpha Telephone | Domain Names | Web Hosting | Get Traffic | xrEvidence | xrSoccer United States Patent
APPARATUS FOR SINGEING TEXTILE FABRICS Apparatus for singeing projecting threads from a web of flat fabric including a convex flame guiding body which is used in conjuction with a stream of compressed air, adapted to be enriched with moisture to limit the depth of penetration of the flame, the compressed air being directed on the side of the flat textile facing away from the flame, the guiding arrangement having guiding surfaces lying one behind the other in the direction of the web, and being inclined 90.degree. in relation to each other.
Attorney, Agent or Firm: We claim: 1. Apparatus for singeing of free-standing fiber, filament or thread loops of flat textiles, especially fabrics, by means of a flame acting on the flat textile which is continuously guided past said flame, comprising: burner means including a slit providing a gas flame issuing from said slit; guiding means for guiding the flat textile in the form of a web continuously past said gas flame at said slit; said guiding means including a bent guide edge across which said web of material is pulled; said burner means having the flame exit slit pointed towards said bent guide edge; a convexly bent flame guiding body opposite said guiding edge; and a flame and fume flue, the exit direction of which lies transversely in relation to the flame exit direction, so that the flame is bent across the flame guiding body and engages only with its outside convex side with the web of the fabric. 2. Apparatus as claimed in claim 1, wherein said guiding means is provided with two guiding surfaces lying one behind the other in the direction of travel of the web and inclined by about 90.degree. in relation to one another and wherein the bent guide edge lies between said two guiding surfaces. 3. Apparatus as claimed in claim 2, wherein the surface of the bent guide edge has a lattice or sieve structure and wherein an air canal is provided within the guiding means, the exit of which canal is directed against the inner side of the bent guide edge. This invention relates to a process for the singeing of free-standing fibers, filaments and thread loops of flat textiles, especially fabrics, by means of a flame acting on a flat textile guided past said flame continuously. The singeing, also called flaming or gassing, of fabric webs is a finishing step in order to eliminate any fine ends of fibers projecting from the surface, as a result of which the flat textiles produced from fibrous yarns exhibit in many instances an undesirable fluffy surface. Among the various singeing processes, the gas singeing process has proven to be the most economical and most favorable one, thereby a relatively good effect in depth can also be achieved. In this case the fabric is guided at a speed of 50 to 250 meters per minute through the open soot free flame, whereby the flame can engage perpendicularly or tangentially the projections in relation to the goods, and is continuously guided past the flame. The difficulty with the traditional singeing process of the type mentioned lies in the fact that metering is complicated and controlling the flame which acts on the flat textile with delicate precision is also difficult in order that the fiber remnants are removed as completely as possible without in any way affecting the body of the fabric. The object of the invention is to provide a process for singeing ends of fibers and loops of filaments and threads projecting from a flat textile, by means of which a particularly effective singeing of the fibers is achieved and the utmost protection of the web of fabric is made possible, and a further object is to provide an apparatus for the economical execution of the process, which apparatus is distinguished by a simple and constructive design. Starting out from the process of the initially mentioned type, the objective will be achieved according to the invention, in that the flat textile in the area of the occurrence of the flame experiences a strong change of direction, i.e., while buckling or bending, and is guided past the flame, whereby the outward bulging and curving side of the web of fabric is acted upon tangentially by the flame, in a manner which is known per se. Because of this measure, the unbound ends of fibers or remnants of fibers will experience an erection and will be laid free, since the area of the web of fabric moving past the singeing flame is, so to speak, stretched or spread out on its treatment side, and consequently the singeing flame can remove the remnants of fibers very effectively. Since the singeing effect depends to a considerable extent on the control of the flames, provision has been made according to another characteristic of the invention, that the singeing flame, emerging obliquely from the burner slit is guided on its side facing away from the web of fabric, via a convexly curved flame guiding body. In this feature, the invention makes use of the knowledge, that, flames have a tendency of fitting against the guiding bodies, so that, as a result of this measure according to the invention, a stabilization of the shape of the flame will be achieved. The flame-guiding effect, can be enhanced still further, according to the invention, if, according to another feature of the invention, the flame is guided across a convex flame guiding body or bodies, and is sucked off after the singeing process. Viewed as a whole, this results in a very precise flame guidance, which can be controlled very accurately corresponding to the pertinent requirements. A preferred embodiment of the process according to the invention is characterized in that the side of the flat textile facing away from the flame, is acted upon by a stream of compressed air directed oppositely to the flame, thereby permitting the stream of compressed air to be enriched with moisture. As a result of this moisturization the depth of penetration of the singeing flame or the depth of the heat effect in the web of fabric can be determined even more precisely. Furthermore, as a result of this, the usually encountered excessive drying of the textile web can be counteracted effectively, particularly since, through adjustment of the degree of humidity of the cooling air, an easy adaptation to the type of material of the textile web that is to be treated each time, is available to the finisher. In order to carry out the process of the invention, there is provided an apparatus, consisting of a gas-singeing machine with one or more series of burners and one or more flame guide arrangements, by means of which the flat textile is pulled continuously past the flame, which is characterized essentially in that the guide arrangement has two guiding surfaces, lying one behind the other in the direction of the web, and being inclined by about 90.degree. in relation to one another. An apparatus developed in such a way, can be produced at favorable cost, and offers a plane-parallel full support for the flat textile and thus assures an always uniform distance of the textile web from the singeing flame and particularly a fold-free pull-off of the textile web. In a preferred embodiment of the apparatus provision is made according to the invention, that the guiding surfaces pass over into one another by way of a rounded edge surface and that they have a lattice or sieve structure at least in the area of the rounded edge, and that the air canals are worked in within the guide arrangement, the exit nozzles of which are directed against the inner circular arc shaped area of transition between the guiding surfaces. The sieve or lattice structure, which should have as fine a gauge as possible, permits an unimpeded striking of the stream of compressed or cooling air, possibly enriched with humidity (moisture) and controllable by way of throttle valves etc., against the side of the textile web facing away from the flame. According to further characteristics of the invention, the guide arrangement can be adjustable in a vertical and horizontal direction, and the singeing burner can be developed as a two chamber burner for the purpose of stabilizing the singeing flame. According to an alternative embodiment, provision can be made according to the invention, that the guiding surfaces are formed by the outside surfaces of two water cooled canals, which are assembled while leaving an air exit slit, and which are adjustable for the purpose of changing the width of the air exit slit. The invention will be explained in more detail on the basis of the drawings. FIG. 1 shows a diagrammatic sectional view of the preferred embodiment of the invention. FIG. 1a shows in perspective a modification of the guiding surfaces of the device of FIG. 1. FIG. 2 shows a tufted rug in cross-section which is made from looped flat textile fabric fed into the machine of the invention and them faced with foamed plastic or foamed latex on the underside. FIG. 3 shows thread loops of a regular size in the fabric which is fed into the machine. FIG. 4 shows a section of this fabric of FIG. 3 which has been singed. The drawings show the fundamental structure of the apparatus according to the invention, which consists of the burner body 1, the guide arrangement developed as table 2, and the suction bell 3. The burner body 1 on the inside has a gas mixture chamber 11, from which the gas-air mixture is introduced via two burner slits 12 into a first combustion chamber 13 and from there via a narrow canal 14, serving for the stabilization of the flame into a second combustion chamber 15, and it then emerges after further stabilizing of the flames, from the burner slit 16. The ramp stone 1a, above the burner body 1 above the burner slit 16 constitutes a convexely curved guiding body 17, to which the flame emerging from the burner nozzle adapts (fits) itself. The suction bell 3 continues upward from the flame guiding body 17, which bell in connection with the combustion chamber and the flame guiding body 17 ensures a very exact (precise) guidance of the flame. The table 2 has a first guiding surface 21, rising somewhat from below to the top, and projecting from the perpendicular, and a horizontally aligned guiding surface 22. The transition between the guiding surfaces 21, 22 is formed by an arc with a relatively small radius, and represents a rounded edge. Canals 23 for the cooling water and an air canal 24 are positioned in the inside of the table. The outlet nozzle of the air canal is directed against the inside wall of the arc shaped transition area of the guiding surfaces 21, 22, which has a lattice or sieve structure, so that the air can strike without impediment the reverse side of the textile web, i.e., the side to which the singeing flame is not tangential. The table is mounted horizontally in the direction of the arrow H and vertically adjustably in the direction of arrow V. The flat textile 5 that is to be singed is pulled past the flame 4 by means of a pulling-off or rolling up apparatus, not shown. In the area of transition between the rising guiding surface 21 and the horizontal guiding surface 22, the textile web is given a break, so to speak, or a relatively sharp curvature, so that the side of the textile web that is to be singed is spread (stretched) in this area and the remnants of fiber are raised and can thus be completely singed by the singeing flame attacking tangentially. Instead of a guide arrangement with two guiding surfaces connected with one another by way of a sieve or lattice, a guide arrangement can be provided according to an alternative embodiment, in which the guiding surfaces 21, 22 are formed each time by the outside surfaces of broad, watercooled canals, which, while leaving an air escape slit, are disposed approximately at right angles to one another and are adjustable for the purpose of changing the width of the air gap. The process and the apparatus of the invention can be used particularly advantageously in the case of production of tufted rugs, produced according to the tufting process, and coated on their underside with foamed plastic. FIG. 2 illustrates schematically, such a tufted rug, into the ground tissue 25 of which threads 26, for example, made of fleecy threads of many endless polyamide filaments are impressed, while forming thread loops 27, 28 above and below the ground tissue 25. The thread loops are then fixed by latex, glue, etc., applied to the lower thread loops 28 and the underside of the ground tissue 25, after which the rug is provided on its underside with a layer 29 of foamed plastic. The plastic layer 29 in this case must be thick enough so the lower thread loops 28 will be embedded in it. The increase in thickness of the layer 29 of foam plastic, however, increases the difficulties the production costs of tufted goods, on the one hand, because of the large quantities consumed and on the other hand because the thickness of the layer 29 requires a predetermined holding time in the apparatus for the development of the foamed layer 29, particularly since we are dealing with the so-called foaming condensation stage in a heating apparatus or furnace. The thinner the layer 29, the greater can be the processing speed at which the goods are guided through the condensation heating apparatus or furnace. After insertion of the thread loops in the ground tissue 25, the thread loops, particularly the lower thread loops 28, are, however, at an irregular size, as illustrated schematically in FIG. 3. In addition the threads during pushing through the ground tissue are subjected to a considerable mechanical stress, so that there are frequent breaks of the filament and therefore many ends 30 of filaments project away from the thread loops 28. In order to embed the thread loops 28 according to FIG. 3 securely in a layer of foam plastic, a thickness of the layer, approximately as indicated at position 31, must be provided. The required thickness for the layer 29, however, is reduced considerably, whenever the intermediate product according to FIG. 3 -- therefore before coating with latex and application of the layer 29 of foam plastic -- is subjected to a flame and heat treatment illustrated in FIG. 1. The intermediate product according to FIG. 3 in this case, is guided past the singeing flame 4, just like the flat textile 5 according to FIG. 1, whereby the thread loops 28 point toward the flame 4. Even upon approach to the singeing flame 4, the projecting ends 30 of the fibers are lightly singed and lightly matted down by the strong heat radiation. In the outlet area of the flames, however, the thread loops 28 too are strongly matted and shrink, so that after the flame treatment one will about achieve the intermediate product, sketched in FIG. 4, in which all of the lower thread loops project to essentially the same degree beyond the ground tissue 25. After the application of latex to the matted thread loops, it will be sufficient to apply the layer of foam plastic only at about the thickness indicated at position 32. As extensive practical trials have shown, it will be possible in this manner to reduce the thickness of the layer 29 of foam plastic by 20 to 50 percent as compared to the usually required thicknesses of foam layers. The flame temperature, naturally, must be adapted to the thread material and must at least have the melting temperature of the thread material, therefore 215.degree. to 245.degree. C in the case of polyamide fibers, or 248.degree. to 256.degree. C in the case of polyester fibers. An inadmissible heating up of the ground tissue 25 and of the visible thread loops 27 is prevented by the cooling air, fed in via the canal 24 and by the sucking off of the combustion gasses and of the flame by means of the suction apparatus 3. For U.S. patent law, rules, and procedures see MPEP. Disclaimer. Information presented on this page while believed to be reliable, is provided "as is" with no warranties of its accuracy or timeliness. For legal advice seek help of a licensed professional. |