Abstract:
Apparatus and method for washing an elongate textile article of extended indeterminate length utilizes a containment structure defining a channel extending upwardly from a lower end to an upper end thereof, with a plurality of undulations spaced-apart from one another within the channel between the lower and upper ends thereof, each undulation extending transversely across the channel. A portion of the lengthwise extent of the traveling textile article is advanced transiently within the channel upwardly from the lower end to the upward end and across the undulations, while a substantially continuous supply of cleansing liquid enters the channel at the upper end to flow downwardly against the upwardly traveling portion of the textile article for cleansing thereof.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates generally to apparatus and methods for the wet processing of textile articles and, more particularly, to apparatus and methods for washing textile articles, e.g., before or after a dyeing operation. 
         [0002]    It has been commonplace for centuries to subject textile articles to various wet processing treatments at varying stages of textile manufacturing operations. As one example, the vast majority of textile articles are dyed at some stage of their overall processing to impart coloration for aesthetic and style reasons. The types of apparatus and processes used for textile dyeing are numerous and diverse. Likewise, the dyes used for such operations are equally varied. Ancillary processes are also commonly carried out on textile articles before and/or after dyeing, e.g., textile articles may be subjected to a washing operation before dyeing to prepare the textile articles to receive dye and, likewise, textile articles may be washed after dyeing to remove excess dye. 
         [0003]    Despite many modern advances in textile chemistry and, particularly, in the development of synthetic dyes and dyeing processes, many textile articles continue to be dyed using natural dyes applied by techniques which have been known and used for centuries. One particular example is the use of plant-derived indigo dyes used in the production of cotton-based denim fabrics. Due largely to the increasing popularity of wearing apparel made of denim, particularly so-called blue jeans, the use of indigo dyes continues to rise despite the relatively primitive nature of the dye and inefficiencies and environmental concerns with its use. 
         [0004]    Indigo dyeing is predominantly performed on textile yarns, e.g., in the form of a traveling rope assembled of multiple individual yarns or in a traveling open sheet of side-by-side yarns, prior to their incorporation into denim fabric. Basically, the dyeing process requires the yarn rope or sheet to be passed into and out of multiple dip baths to progressively build penetration of the dye into the constituent yarns. Preparatory to dyeing, the yarns may be washed to remove impurities such as natural oils, waxes, and foreign matter which typically are found in natural cotton fibers. Likewise, after the yarn rope or sheet has undergone a sufficient number of dippings to achieve a desired dye shade, the yarns must then be washed through a series of water rinse baths to remove excess dye which remains on the yarn surfaces without having penetrated into the yarns. 
         [0005]    Although machinery has been developed to automate these operations, this basic process of indigo dyeing has remained largely unchanged. Overall, the process presents many environmental concerns due to the substantial volumes of water which must be utilized for the numerous dip baths and for pre-dyeing and post-dyeing washings and, in turn, the substantial volumes of dye solution and dirty wash water which must be cleaned. In recent years, considerable effort has been devoted to developing advanced techniques for rehabilitating dye solutions and dirty wash water, but little effort has been successfully devoted to reducing the amount of water used in the first place. 
         [0006]    Accordingly, a need exists within the textile industry for improved apparatus and processes used in the wet processing of textile articles, particular in association with textile dyeing operations, by which the amount of clean water devoted to the such wet processing operations can be reduced thereby lessening the required clean-up and attendant environmental impact. 
       SUMMARY OF THE INVENTION 
       [0007]    It is accordingly an object of the present invention to improve the apparatus and methods used for the washing of textile articles to lessen the amount of clean water or other cleansing liquid required. A more specific object of the present invention is to provide an improved apparatus and method for rinsing indigo-dyed yarn ropes or sheets using a substantially reduced volume of water as compared to known conventional rinsing operations. A further object of the present invention is that such improvements may find a broader applicability in other textile wet processing operations. Still further objects and benefits of the present invention will be apparent from the following disclosure of a preferred embodiment of the invention. 
         [0008]    Briefly summarized, the present invention provides an apparatus for washing an elongate textile article of extended indeterminate length, and basically comprises a containment structure defining a channel extending upwardly from a lower end to an upper end thereof, with a plurality of undulations spaced-apart from one another within the channel between the lower and upper ends thereof, each undulation extending transversely across the channel. An arrangement is provided for guiding the elongate textile article to travel in its longitudinal extent with a portion of its lengthwise extent advancing transiently within the channel upwardly from the lower end to the upward end and across the undulations. A substantially continuous supply of a cleansing liquid, e.g., water, is delivered into the channel at the upper end for downward flow against the upwardly traveling portion of the textile article for cleansing thereof. 
         [0009]    As noted, the apparatus is particularly adapted for rinsing indigo dyestuff from an elongate textile rope or sheet comprised of multiple textile yarns and containing an indigo dye partially penetrated into the yarns and partially residing on surfaces of the yarns from which rinsing of the indigo dye is required. However, the present invention is not intended to be so limited in its potential uses and application, but is believed to be equally applicable to other textile rinsing and/or washing operations for other types of textile articles. 
         [0010]    In a preferred embodiment of the present apparatus, the channel may have a lateral dimension sufficient for a plurality of the elongate textile articles to travel alongside one another within the channel. According to another aspect of the invention, the containment structure preferably defines an open front to the channel for viewing of the rinsing action on the traveling textile article. The channel preferably extends at an inclined upward angle. More preferably, the containment structure may have an upwardly inclined bottom wall bordered by two lateral side walls which define the channel therebetween. The undulations may comprise transverse corrugations spaced along the bottom wall of the containment structure. 
         [0011]    In a preferred embodiment, the arrangement for guiding the elongate textile article may comprise guide rollers adjacent the lower and upper ends of the channel and, more particularly, the guide rollers may comprise a pair of nip rollers disposed adjacent the upper end of the channel for squeezing excess rinse water or other cleansing liquid from the textile article after exiting the channel. Advantageously, the nip rollers may be disposed to redirect the squeezed rinse water or cleansing liquid into the channel. 
         [0012]    Preferably, the supply of water or other cleansing liquid is adapted to flow gravitationally into and through the channel. For example, the supply of water or other cleansing liquid may comprise a weir disposed to overflow into the upper end of the channel. It is further preferred that a vessel is disposed adjacent the lower end of the channel for collecting rinse water or other cleansing liquid flowing from the lower end of the channel. 
         [0013]    In a particularly advantageous installation of the present apparatus, a plurality of the apparatus may be arranged adjacent one another for travel of the textile article in sequence through the respective channels thereof. In such an installation, each apparatus may comprise a vessel disposed adjacent the lower end of its respective channel for collecting rinse water or other cleansing liquid and conduits may be provided to connect the vessels in sequence to provide for counterflow of the collected water or other cleansing liquid to the preceding apparatus. 
         [0014]    According to another aspect of the present invention, a method is provided for washing an elongate textile article of extended indeterminate length. Briefly summarized, the method comprises the basic steps of guiding the elongate textile article to travel in its longitudinal extent with a portion of the lengthwise extent of the textile article advancing transiently within a channel along an upwardly inclined path and across a plurality of spaced-apart transverse undulations within the channel, while a substantially continuous supply of water or other cleansing liquid is delivered into an upper end of the channel for downward flow against the upwardly traveling portion of the textile article for cleansing thereof. 
         [0015]    In a preferred embodiment of the method, excess rinse water or other cleansing liquid is squeezed from the textile article after exiting the channel. It is further preferred that the rinse water or other cleansing liquid be flowed gravitationally into and through the channel. The rinse water or other cleansing liquid is preferably collected at a lower end of the channel. In an advantageous installation, the guiding and delivering steps are repeated multiple times in sequence until the textile article achieves a desired cleanliness. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The accompanying drawings and the following description thereof are provided for illustrative purposes in describing one possible embodiment of the present invention, but without limitation on the overall scope, substance and broader applicability of the invention in other embodiments. 
           [0017]      FIG. 1  is a schematic diagram depicting a conventional prior art form of dye range for the indigo dyeing and rinsing of textile yarn ropes; 
           [0018]      FIG. 2  is a schematic diagram depicting an apparatus in accordance with a preferred embodiment of the present invention for rinsing indigo dye from textile yarn ropes; and 
           [0019]      FIG. 3  is a photograph depicting a close-up image of the rinsing action achieved in the apparatus of  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0020]    Referring now to the accompanying drawings and initially to  FIG. 1 , a typical conventional form of textile dye range used for the indigo dyeing of textile yarn ropes is schematically depicted and basically comprises a creel section indicated generally at  10 , a dyeing section indicated generally at  12 , a washing/rinsing section indicated generally at  14 , a drying section indicated generally at  16 , and a coiling section indicated generally at  18 . The creel section  10  comprises a plurality of storage beams  11  from which a corresponding plurality of textile yarn ropes  20  are delivered via an overhead guide structure  22  to an entrance end of the dyeing section  12 . The dyeing section  16  comprises a series of vats  24 , each containing an indigo dye solution, with guide rollers  26  disposed above and within each vat  24  for directing the ropes  20  to travel into and out of the dye solution. A superstructure  26 , sometimes referred to in the industry as a “skying” section, is situated above the series of vats  24  and comprises a series of multiple guide rollers  30  by which the yarn ropes  20  are elevated out of each bath to allow for oxidation and penetration of the dye into the yarn ropes before immersion in the next following vat  24 . The number of vats  24  may vary depending on the depth of shade to be imparted to the yarn ropes  20 . 
         [0021]    Following the dyeing section  12 , the yarn ropes are directed from the superstructure  28  into a series of rinse baths  32  in the washing/rinsing section  14 , each bath  32  being filled with a quantity of water within which the ropes  20  are guided via rollers  33  in a serpentine path to progressively rinse excess indigo dye from the ropes  20 . The number of rinse baths  32  may vary in relation to the number of dye vats  24  and, in turn, according to the amount of retained excess indigo dye required to be removed from the ropes  20 . Following the last rinse bath  32 , the ropes are directed to the drying section  16  wherein the ropes follow a serpentine path about a series of drying drums  34  and are then directed to the coiling station  18  at which each rope  20  is respectively directed to a coiler mechanism  36  which lays the rope  20  into a storage container  38  in a series of overlapping coils until the container is filled. 
         [0022]    As previously indicated, one of the inefficiencies and environmental disadvantages of conventional indigo dye ranges of the type of  FIG. 1  is the significant volume of water required in the washing/rinsing section  14  to sufficiently remove the excess indigo dye before the ropes  20  can be dried and coiled into the storage containers  38  for further processing. The present invention provides an alternative form of washing/rinsing section  114 , depicted in  FIG. 2 , which can be substituted for the washing/rinsing section  14  in conventional dyeing ranges and which will perform an equally effective rinsing of excess dye using a substantially reduced volume of water. 
         [0023]    With reference now to  FIG. 2 , the washing/rinsing section  114  of the present invention comprises a series of rinsing apparatus  132  which do not rely upon or utilize a contained bath of rinse water. Each rinse apparatus  132  basically comprises an elongated angularly-upstanding rinsing containment structure  140  having a bottom wall  142  flanked by spaced-apart lateral side walls  144  collectively defining therewithin a channel  146  extending upwardly at an incline from a lower end  148  to an upper end  150 . Within the channel  146 , the bottom wall  142  is formed with a plurality of undulations  152 , preferably in the form of a series of angular corrugations projecting forwardly from the bottom wall  142  at spacings along the length of the channel  146 , each undulation  152  extending transversely across the channel  146  between the opposing side walls  144 . 
         [0024]    Each rinsing apparatus  132  further includes a superstructure  154  situated directly above the containment structure  140 . The superstructure  154  supports a weir  156  disposed adjacent and directly above the upper end of the channel  146  and continuously fed with a flow of water from a water feed  158  to overflow into and flow gravitationally downwardly through the channel  146 . The superstructure  154  also supports a pair of nip rollers  160  spaced slightly above the weir  156  with the nip location between the rollers disposed directly above the upper end  150  of the channel  146 . The lower end of the containment structure  140  extends into a collection vessel  162  which includes a series of guide rollers  164 . The collection vessels  162  of the respective rinsing apparatus  132  are connected for water flow between each other by a series of conduits  166 . 
         [0025]    The operation of the washing/rinsing section  114  of the present invention may thus be understood. As previously indicated, the washing/rinsing section  114  would be situated in place of the washing/rinsing section  14  in an otherwise conventional indigo dye range such as that shown in  FIG. 1 . Thus, the washing/rinsing section  114  will receive one or more textile yarn ropes  20 , typically a plurality of such ropes, each of an elongate extended indeterminate length, traveling lengthwise in side-by-side slightly spaced-apart relationship as delivered from the dyeing section  12 . The incoming ropes  20  are directed into the first rinsing apparatus  132  and trained in serpentine fashion about the guide rollers  164  within its collection vessel  162 . From the last guide roller  164 , the ropes  20  are directed into the lower end  148  of the channel  146  and then upwardly through the full length of the channel  146  of the containment structure  140  to travel across and in contact with or at least close proximity to the series of undulations  152 , with the ropes  20  exiting the upper end  150  of the channel  146  and proceeding immediately into the nip between the nip rollers  160 . 
         [0026]    As the ropes  20  progress in this path of travel, water from the weir  156  continuously counter flows gravitationally downwardly through the channel  146  against the upwardly moving ropes  20  to rinse the portion of the length of each rope  20  transiently advancing upwardly through the channel  146 . As the wetted ropes  20  pass between the nip rollers  160 , the ropes  20  are squeezed by the rollers  160 , causing the water squeezed from the ropes  20  to fall gravitationally into the upper end of the channel  146 . The collection vessel  162  collects the downward flow of water exiting the lower end  148  of the channel  146  and exhausts the collected water via an exhaust opening  170 . Following the nip rollers  160 , the ropes pass about another guide roller  168  and are directed downwardly therefrom into the collection vessel  162  and about the guide rollers  164  thereof within the next following rinsing apparatus  132  to undergo the same process. 
         [0027]    The undulations  152  in the containment structure  140  contribute to the effectiveness of the rinsing apparatus  132  by periodically interrupting the gravitational flow of the rinse water and causing the rinse water to be diverted outwardly to penetrate into and through each rope  20 .  FIG. 3  is a photograph taken of an actual demonstration prototype of the rinsing apparatus  132  during a non-production operation conducted for demonstrative developmental purposes and depicts the action of the gravitationally flowing rinse water at the location of one undulation  152 . This water action induced by the undulations  152  promotes more rapid rinsing of surface dye from the constituent yarns in the ropes  20  than can be achieved by merely passing the ropes  20  through a non-moving bath of water as in conventional dye ranges. 
         [0028]    As will be readily recognized and understood by persons skilled in the industry, the volume of water required by each rinsing apparatus  132  to perform the ongoing rinsing operation will be substantially reduced in comparison to the volume of water required to be maintained within the rinse baths  32  in a conventional indigo dye range. Although empirical testing of the present apparatus and method in actual operation has not yet been performed, it is presently anticipated that the amount of required water may be reduced by about 30%, but actual results in a given embodiment of the invention could be greater or lesser. An additional feature of the present invention is that the rinse water collected in the collection vessel  162  of each rinsing apparatus  132  is exhausted via its exhaust opening  170  into the collection vessel  162  of the immediately preceding rinsing apparatus  132  from which the water may in part be directed to the weir  156  of such rinsing apparatus  132 , which further contributes to the overall water savings. The number of rinsing apparatus  132  required to make up a washing/rinsing section  114  in any given indigo dye range will depend upon various factors, including but not limited to the number of dyeing vats  24  making up the dyeing section  12 , but it is anticipated that the number of rinsing apparatus  132  would be no greater than and potentially less than the number of rinse baths  32  conventionally required. 
         [0029]    An additional advantage of the present washing/rinsing section  114  is that the channel  146  is open at the forwardly facing side of each containment structure  140 , which enables operational personnel to visually inspect the clarity of or, alternatively, the dye coloration in the rinse water flowing through each channel  146  in each rinsing apparatus  132  so as to monitor the effectiveness of the rinsing operation. In turn, adjustments may be made in operational parameters, such as water flow rate, etc., as necessary to achieve the desired degree of rinsing of the ropes using the least amount of water required. 
         [0030]    It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof.