Device to dry textile materials

Abstract: Device (10) to dry textile materials such as yarns (14), woven fabrics, etc. which cooperates advantageously with apparatuses that treat such materials continuously such as mercerising machines, stenters, etc. and with means that take up the textile materials thus treated, the device (10) consisting of: a heater body (11) employing a forced (22) circulation (21) of air, assemblies of upper (12) and lower (13) rolls which pass the textile materials through the heater body (11), means (27-28) that deliver air from the exterior (25) towards the inside (29) of the heater body (11), and means (24) that heat the air thus delivered, and means (32-33) that remove the air from the inside of the heater body (11) towards the exterior (31), the quantity of air delivered (29) into the heater body (11) being coordinated with the quantity of air discharged (31) from the heater body (11).

Description: This invention concerns a device to dry textile materials; to be more exact, the invention concerns a drier device suitable to cooperate with apparatuses that treat textile materials continuously such as mercerising machines, stenters and other like apparatuses comprising the features of the preamble of claim 1. Such a device is known, for example, from DE-A-1 635 277. By textile materials are meant yarns or pluralities of yarns, woven fabrics, fitted textile carpets or other like materials. The state of the art covers a plurality of drier devices used in the textile field and elsewhere on materials which are unwound continuously; these known devices employ a variety of drier means in cooperation with an enormous range of heater means. DE-A-1.635.277 includes a device to dry textile materials such as yarns, woven fabrics, etc. which cooperates advantageously with apparatuses that treat such materials continuously such as mercerising machines, stenters, etc. and with means that take up the textile materials thus treated, the device comprising a heater body, containing an assembly of upper rolls and an assembly of coordinated lower rolls which pass the textile materials through the heater body, and a forced circulation of hot air is maintained within the heater body. Said device also effects a system to dry bundles of parallel yarns which comprises a plurality of emitter nozzles cooperating with upper and lower rolls; intake openings are included at an intermediate position at the sides of the bundles of yarns; this patent also includes upper and lower fans for the recirculation of air; this fact entails high costs of construction, running and maintenance besides placing the machine operator in precarious conditions. Moreover the yarns are lapped by streams of non-homogeneous air, and this situation creates conditions of stress in the yarns themselves. WO 83/02312 includes an air changing system with two valves and a system for heating air entering immediately upstream of the intake valve; this solution not only does not keep the chamber under overpressure but immits streams of replacement air which are not homogeneous nor controlled. So far as the present applicant is aware, however, embodiments such as those disclosed in this invention are not known in the state of the art. The present applicant has the purpose of providing an efficient, simple drier device able to meet the most stringent requirements of the market. The invention is set forth in the main claim, while the dependent claims describe various features of the invention. The drier device according to the invention consists of a drier body within which the textile material, for instance a bundle of parallel yarns, to which we shall refer in the description that follows, is made to run continuously. But it should be clearly understood that other materials such as woven fabrics, fitted textile carpets and analogous materials can also be processed. The material leaving the drier body is thereafter taken up on means suitable for the purpose. The bundle of yarns upstream of the drier body is passed through a water removal assembly and is thereafter lapped within the drier body by a draught of hot air produced by forced circulation. The air is heated advantageously, but not only, by a submerged combustion means. The system of working and the embodiment of the drier device according to the invention are such as to obtain the continuous drawing of a quantity of air from outside the device, this quantity balancing a substantially equivalent discharge of air from within the device towards the outside. Means are included to check the relative humidity of the bundle of yarns leaving the device and can control and condition the state of entry and exit of air into and from the drier device. Means are also comprised to check the temperature of the air within the device and can condition the parameters of the heating of the air. These features of the invention will be made clearer in the description that follows. The attached figures, which are given as a non-restrictive example, show the following:- Fig.1 gives a diagram of a drier device according to the invention; Fig.2 is a three-dimensional drawing of a detail of the device of Fig.1. In Fig.1 a drier device 10 of the invention consists of a heater body 11 which contains an assembly 12 of upper rolls and an assembly 13 of coordinated lower rolls. A bundle of yarns 14 is passed alternately between the upper rolls 12 and lower rolls 13 within the body 11. The bundle of yarns 14 reaches the drier device 10 in the direction of the arrow 15 after undergoing a wet treatment, for instance continuous mercerising of the type disclosed in application IT-A-83488 A/89 in the name of the present applicant. The bundle of yarns 14, before entering the heater body 11 of the drier device 10, passes advantageously through a water removal assembly 16, which consists of a Venturi tube 17 (see Fig.2) cooperating with a first aspirator fan 18 equipped with its own motor 19. The combined action of the Venturi tube 17 and aspirator fan 18 causes removal of humidity according to the arrow 20 from the bundle of yarns 14, which upon entry into the heater body 11 may possess advantageously a degree of relative humidity of about 70%. During its series of passes between the upper 12 and lower 13 rolls the bundle of yarns 14 is lapped by a draught of hot air circulating according to the arrow 21 within the heater body 11. This air is circulated by a second fan 22 driven by its own motor 23. The bundle of yarns 14 leaving the heater body 11 possesses a relative humidity of about 7 to 8%. The yarns 14 thus dried can be taken up thereafter on a suitable take-up means such as a beam or, if they are divided into groups, on a plurality of beams. The heating of the air circulating within the heater body 11 at a temperature within a range of about 90° to 120°C is achieved by means of a so-called submerged combustion system, which provides for the heater means, in this case a burner 24, to be immersed directly in the air to be heated. The air to be heated is drawn from the exterior according to the arrow 25, is filtered 26 and then is passed through a pipe 27 by a third fan 28, which is connected advantageously to its own motor 23. The air which is delivered along the pipe 27 according to the arrow 29 into the heater body 11 may be pre-heated by a suitable means 30 located in the pipe 27 downstream of the filter 26. The air heated in the pipe 27 is introduced into the heater body 11 in a quantity proportional to a coordinated quantity of air discharged through a stack 32 according to the arrow 31. To this end a valve 33 is positioned in the stack 32 so as to regulate the flow of air discharged and is operated by a hygrometer 34 that measures the percentage of relative humidity found in the bundle of yarns 14 leaving the drier device 10. In this way are obtained an efficient control and sustainment of ideal working conditions of the system of hot air and bundle of yarns 14. A thermometer 35 to measure the temperature of the hot air circulating within the heater body 11 according to the arrow 21 is also included. This thermometer 35 cooperates suitably with the feed of air 36 and gas 37 to the burner 24. We have described here a preferred embodiment of the invention but many variants are available to a person skilled in this field without departing thereby from the scope of the invention as claimed. For instance, it can be pointed out that the system to heat the air by submerged combustion can be replaced by other known combustion systems suitable for the purpose.

Claims: Device to dry textile materials such as yarns, woven fabrics, etc. which cooperates advantageously with apparatuses that treat such materials continuously such as mercerising machines, stenters, etc. and with means that take up the textile materials thus treated, the device comprising: a heater body (11), containing an assembly of upper rolls (12) and an assembly of coordinated lower rolls (13) which pass the textile materials (14) through the heater body (11); a forced (22) circulation (21) of hot air is maintained within the heater body (11); characterized in that: the forced air (21) within the heater body (11) is circulated by a single fan (22); means (27) deliver air from the exterior (25) towards the inside (29) of the heater body (11); means (24) for heating the air thus delivered; means (32-33) which remove the air from the inside (29) of the heater body (11) towards the exterior (31); the delivery means (27) include fan means (28) to maintain an overpressure, so that the quantity of such air (29) delivered into the heater body (11) being coordinated with the quantity of air discharged (31) from the heater body (11); a water removal assembly (16) is included at the yarn intake side of the heater body (11); and the intake side and the outlet side of the heater body (11) are associated with means that deviate the circulating of air. Device (10) as in Claim 1, in which the water removal assembly (16) consists of a Venturi tube (17) through the length of which there passes the bundle of parallel yarns, the Venturi tube (17) being connected to aspiration means (18) equipped with their own motor (19). Device (10) as in Claim 1 or 2, in which the water removal assembly (16) comprises at its inlet an assembly to drain water from the yarns. Device (10) as in any claim hereinbefore, in which the means (24) to heat the air are of a submerged combustion type. Device (10) as in any claim hereinbefore, in which means (30) to pre-heat the air are included upstream of the means (24) that heat the air. Device (10) as in any claim hereinbefore, in which the feed (36-37) of air to the air heating means (24) is governed by a thermometer (35) that measures the temperature of the air circulating within the heater body (11). Device (10) as in any claim hereinbefore, in which the means (32-33) that remove the air from the heater body (11) are governed by a hygrometer means (34) that measures the relative humidity of the textile material leaving the heater body (11).

Inventors: CACCIA DOMINIONI AMBROGIO, CASASOLA LUCIANO, GERIN UMBERTO, LANCEROTTO FABIO, CACCIA DOMINIONI, AMBROGIO, CASASOLA, LUCIANO, GERIN, UMBERTO, LANCEROTTO, FABIO
Applicants: GESMA SPA, GESMA - GESTIONE SVILUPPO MEDIE AZIENDE SPA
Application year: 1990
Main classification: F26B13
IPC codes: F26B13, F26B21