Abstract:
A method of processing textile material is disclosed in which the material ( 13 ) is passed along a predetermined path through a liquid jet device ( 50, 70, 80, 90, 100, 120, 130 ) applying a force to the material ( 13 ) transversely to the axis of the material ( 13 ). High pressure water is used to form one or more belts ( 11, 12 ) for applying twist to a yarn ( 13 ), sliver or roving ( 273 ), or as a jet to intermingle one or more yarns ( 13 ). The water may serve to cool the yarn ( 13 ) after beating in a false twist process.

Description:
This Application is a continuation of International Application No. PCT/GB00/02610, with an international filing date of Jul. 7, 2000, now pending, and herein incorporated by reference. 
    
    
     TECHNICAL FIELD 
     This invention relates to the processing of textile materials, in particular the jet texturing of filament and/or staple products. Such processing includes the false twisting of textile filament yarns, intermingling of multifilament yarns, the co-mingling of two or more filament yarns, the combining of filament and staple yarns and the twisting of staple products, i.e. yarn, sliver or roving. 
     BACKGROUND OF THE INVENTION 
     It has been proposed to apply a false twist to a textile filament yarn by passing the yarn through a texturing jet in which a jet or jets of air are directed onto the travelling yarn offset from its axis to impart a twisting torque to the yarn. The twist levels achievable by this method are very low by comparison with those achieved by the use of friction discs, belts and the like, hence the limited use commercially. The diameter of a textile yarn is relatively small, for example 0.2 mm for 150 Denier, and in consequence the tolerances on jet manufacture are extremely tight if satisfactory processing is to be achieved and consistency of performance from jet to jet. From a production costs point of view it is desirable to increase the yarn processing speed as much as possible. However, a limit on such speed is the surge speed, the speed at which satisfactory processing breaks down due to the long uncontrolled lengths of yarn in the large machines required for economic production. 
     It is also known to process one or more multifilament textile yarns by passing the yarn or yarns through a jet device in which a jet or jets of air are directed transversely of the travelling yarn or yarns to agitate the filaments or the fibres of the yarns. Such agitation may cause uniform texturing or intermittent texturing, i.e. intermingling or co-mingling. When intermittent, nips are produced in the yarn or yarns at spaced intervals. Since such jets rely on air turbulence, the degree of texturing or of nip spacing along the yarn is in consequence random. Whilst the average degree of texturing or nip production per unit length of yarn processed by such known jets may be satisfactory for certain textile applications, there are often long lengths of yarn produced having no texture or nips. These lengths of yarn, when used in knitted or woven fabrics, manifest themselves as unsatisfactory regions in the fabric. 
     Furthermore, it is also known to apply a twist to a textile staple product to give the product satisfactory coherence by passing the product through a twisting jet in which a jet or jets of air are directed onto the travelling product offset from its axis to impart a twisting torque to the product. The diameter of a textile product is relatively small, for example 0.6 mm for a 24 s Ne c  (English cotton count) yarn, and in consequence the tolerances on jet manufacture are extremely tight if satisfactory processing is to be achieved and consistency of performance from jet to jet. 
     Typically a textile machine for performing any of the above processes can have over 200 processing stations, i.e. over 200 yarns are processed simultaneously in parallel threadlines. This means that the machines are very large, which leads to problems of ergonomics. Furthermore, the provision of tight tolerance jets and high pressure air to such jets is expensive and such machines are very noisy, particularly when one or more doors of jet boxes are open for threading purposes. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a method of processing textile materials, which overcomes, at least to a substantial extent, the above-mentioned disadvantages of known processing methods. It is also an object of the invention to enable the size of a machine for performing any one of the above mentioned processes to be reduced by a significant amount. It is a further object of the present invention to provide a method of texturing a textile filament yarn that increases twist levels that can be achieved, increases the surge speed during false twisting or produces more regular texturing along the length of the yarn. It is a further object of the present invention to provide a method of applying a twist to a textile staple product during the staple drawing process which increases twist levels that can be achieved or allows an increase of processing speed for the same twist level. 
     The invention provides a method of processing textile material comprising passing the material along a predetermined path through a liquid jet device applying a force to the material transversely to the axis thereof. The force may be a rotational force. 
     The invention also provides a method for producing textured textile materials, in which the material is textured by the above method and is cooled. The material may be cooled by the liquid jet device. The material may be heated prior to being cooled and textured, and may then be wound up. The material may be drawn prior to being cooled and textured. The method may also comprise applying a forwarding force or a retarding force to the material. The method may comprise applying at least one jet of liquid to the surface of the material transversely to the axis thereof. The method may comprise applying the at least one jet of liquid with components of velocity both axially of and transversely to the material path through the jet device. The method may comprise applying a plurality of jets of liquid disposed about the axis of the material path through the jet device. Preferably the liquid is water and may be cold water. The supply of water may be pulsed. The method may also comprise passing the material successively through a plurality of liquid jet devices. Consecutive jet devices may apply rotational forces to the material in the same or in opposite directions. 
     The material may be cooled in a cooling zone by immersion in a cooling liquid, in which case the cooling liquid may be moved in contraflow to the material passing through the cooling zone. The cooling zone and the liquid jet device may be contiguous. The cooling liquid may be the liquid of the jet device. The process may comprise heating the material by vapour, which may be superheated steam. 
     The invention also provides a method for applying a false twist to a filament yarn, in which the false twist is applied to the yarn by the above method and the yarn is cooled. The yarn may be heated prior to being cooled and twisted, and may then be wound up. The yarn may be passed through a twist trap, a heating zone, a cooling zone and the liquid jet device, being twisted by the latter so that the twist runs back to the twist trap, and then wound up. The yarn may be heated as far upstream as the twist trap. The yarn may be heated prior to passing through the twist trap and not further heated between the twist trap and the liquid jet device. The yarn may be drawn prior to being cooled and twisted. The yarn may be post treated prior to it being wound up. In this case the yarn may be passed with controlled overfeed through further heating apparatus. The further heating apparatus may comprise vapour heating, which may be superheated steam. 
     The method may comprise controlling the material by a feedback arrangement. In this case a property of the material may be measured and the measurement used to control the material processing. The measurement may be used to control the liquid jet device, a speed of the material or a heating step. 
     The material may be a continuous filament yarn and the method may comprise drawing the yarn to form a partially oriented yarn. Alternatively the material may be a plurality of yarns that are combined to form a single coherent yarn. One of the yarns may be a staple yarn. 
     The invention may also comprise apparatus for processing a textile material comprising a liquid jet device adapted to apply a force to a textile material transversely to the axis of the material as the material travels along a predetermined path through the jet device. The force may be a rotational force. 
     The apparatus may comprise cooling apparatus. The cooling apparatus may be a fluid cooling apparatus in which the material passes through a fluid to be cooled by heat transfer thereto. 
     The cooling apparatus may comprise a cooling chamber with a fluid inlet and a fluid outlet for cooling fluid to be passed therethrough, and a material inlet and material outlet. The cooling fluid may be passed contraflow relative to the material. The cooling chamber may comprise seals against escape of cooling fluid at the material inlet and the material outlet. The seals may be labyrinth seals and may be pressurised. The seals may be gas pressurised, and may be pressurised by compressed air. The cooling fluid may be a liquid and may be water. The flow of liquid through the cooling chamber may be arranged to be turbulent. The liquid jet device and the cooling apparatus may have a common liquid. Alternatively, the cooling apparatus may comprise the liquid jet device. 
     The apparatus may also comprise heating apparatus, which may be disposed upstream of the cooling apparatus. The apparatus may comprise winding apparatus disposed downstream of the liquid jet device. The apparatus may also comprise drawing means, which may be disposed upstream of the cooling apparatus. The heating apparatus, cooling apparatus and liquid jet device may be mounted in a common housing. 
     The liquid jet device may be adapted to apply a force to the travelling material along the axis of the material, i.e. a forwarding force or a retarding force. The jet device may apply at least one jet of liquid to the surface of the material transversely to the axis thereof, and the at least one jet of liquid may be offset from the axis of the material. The at least one jet of liquid may be directed to have velocity components both along and laterally of the material path through the jet device. A plurality of jets may be disposed about the material path through the jet device, preferably symmetrically. Three such jets may be provided. The liquid jet device may comprise a housing having an axial bore terminating in a material constricting outlet, the axis of the bore defining a material path therethrough, with at least one liquid flow channel aimed towards the outlet and offset from the axis. The liquid jet device may comprise a seal in the housing against liquid escape along the material path. The seal may be a labyrinth seal and may be pressurised. The seal may be gas pressurised, and may be pressurised by compressed air. Preferably the liquid jet device comprises a water jet device. A plurality of liquid jet devices may be disposed successively along the material path, and the plurality of jet devices may be provided in a common housing. Three such jet devices may be so provided. Consecutive liquid jet devices may be adapted to apply rotational forces to the product in the same or in opposite directions. 
     The heating apparatus may comprise a vapour heating apparatus. The vapour may be superheated steam. The heating apparatus may comprise a housing having seals against escape of steam at a material inlet and at a material outlet thereof. The seals may be labyrinth seals and may be pressurised. The seals may be gas pressurised, and may be pressurised by compressed air or by superheated steam. The heating apparatus, the cooling apparatus and the liquid jet device may be disposed in a common housing. 
     The apparatus may also comprise treatment means operable to post treat the yarn. In this case, the apparatus may comprise feed means operable to pass the yarn with controlled overfeed through a further heating apparatus. The further heating apparatus may be a vapour heating apparatus. The heating apparatus and the further heating apparatus may use the same vapour in sequence. 
     The apparatus may comprise a feedback arrangement operable to control the material processing. The feedback arrangement may comprise a measuring instrument operable to measure a property of the material and produce a signal proportional to the measurement, and control means operable in response to the signal to control the material processing. The control means may be operable to control the liquid jet device, a speed of the material and/or a heating step. 
     The jet device may be arranged in a filament spinning apparatus, and may be arranged in the path of a plurality of yarns. The jet device may be disposed downstream of a further cooling arrangement. The further cooling arrangement may be a fluid cooling arrangement in which the material passes through a fluid to be cooled by heat transfer thereto. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described with reference to the accompanying drawings in which: 
     FIG. 1 is a schematic diagram of a water jet twisting device, 
     FIG. 2 is a cross-section of a water ‘belt’ jet, 
     FIG. 3 is a cross-section of an alternative water ‘belt’ jet, 
     FIG. 4 is a schematic diagram of a four ‘belt’ jet twisting device, 
     FIG. 5 is a cross-section and plan of a ‘wrap’ jet twisting device, 
     FIG. 6 shows the water ‘wrapped’ around the yarn in the device of FIG. 5, 
     FIG. 7 shows a ‘wrap’ jet twisting device with a conical yarn passage, 
     FIG. 8 shows a ‘wrap’ jet twisting device with a stepped yarn passage, 
     FIG. 9 shows a ‘wrap’ jet twisting device with a separate water exit channel, 
     FIG. 10 shows a cylinder jet twisting device, 
     FIG. 11 is a section on the line B—B of FIG. 10 of the cylinder jet device, 
     FIG. 12 is a section through a miniature twist jet, 
     FIG. 13 shows a multi-jet assembly, 
     FIG. 14 shows a conventional false twist texturing machine, 
     FIG. 15 is a section through an all-in-one jet device, 
     FIG. 16 is an enlarged view of the heater part of the jet device of FIG. 15, 
     FIG. 17 is alternative embodiment of false twist texturing machine, 
     FIG. 18 is a longitudinal section of a texturing slot jet device, 
     FIG. 19 shows a three hole intermingling jet device, 
     FIG. 20 shows cross sections through two four hole jet devices similar to that of FIG. 19, 
     FIG. 21 shows a texturing jet device with a plug former, 
     FIGS. 22 and 23 are threadline diagrams of alternative filament spinning apparatus incorporating the jet devices of FIGS. 18 to  21 , 
     FIG. 24 is a yarn co-mingling machine incorporating the jet devices of FIGS. 18 to  21 , 
     FIG. 25 is a section through a drafting and twisting jet device for staple yarns, and 
     FIG. 26 shows a threadline diagram of a staple twisting machine 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, there is shown schematically a water jet device  10  in which two jets or water ‘belts’  11 ,  12  cross on opposed sides of a running yarn  13 , the belts  11 ,  12  and the yarn  13  moving in the directions shown by the arrows. The belts  11 ,  12  act to twist the yarn  13  and at the same time forward the yarn  13 . This action is similar to that of conventional crossed belt twisting devices. To generate each of the belts  11 ,  12 , as shown in FIG. 2, a water belt jet  20  has a top block  21  and a bottom plate  22 . High pressure water is introduced into the interior  23  of the block  21  through an inlet  24 , and passes out of the chamber  23  through an outlet  25  in the form of a water ‘belt’  26 . The belt  26  is brought into contact with the yarn  13  by moving the block  21  adjacent the yarn  13 . For easier water removal, a water belt jet  30  may have the bottom plate  31  curved as shown in FIG.  3 . The water belt  33  adheres to the surface of the bottom plate  31  due to Coanda effects, and in consequence is more easily brought into precise contact with a small diameter yarn  13 . In FIG. 4 there is shown schematically a four belt water jet device  40 . In this case there are two belts  41 ,  42  which act in the same manner as belts  11 ,  12  of FIG.  1 . Spaced from the belts  41 ,  42  along the yarn  13  are two further belts  43 ,  44 . Such an arrangement controls and holds the yarn  13  in position better than the device  10 , in which there may be a tendency for the yarn  13  to vibrate and thereby be of reduced quality. 
     In FIG. 5 there is shown an alternative form of water jet device  50 . The jet device  50  consists of a base  51  and a lid  52 . These are located in contact with each other by locating pins  53 . A high pressure water inlet  54  and a yarn passage  55  are provided in the base  51 . Connecting the water inlet  54  and the yarn passage  55  is a water channel  56 . The water belt emerging from the water channel  56  impinges on the yarn  13  tangentially so as to create a vortex and wrap itself around the yarn  13  several times as it passes along the yarn passage  55  as shown in FIG.  6 . This arrangement provides a very efficient twisting unit. More than one water channel  71 ,  72 ,  73  may intersect the yarn passage  74  as shown in the jet device  70  in FIG.  7 . In this case the yarn passage  74  is of conical form so that the increased diameter along the yarn passage  74  can accommodate the increase in the volume of water as each water belt emerges therein. As an alternative to the conical form of yarn passage  74 , a stepped yarn passage  81  may be provided in the jet device  80  of FIG.  8 . Such a yarn passage  81  is easier to machine than yarn passage  74 . In the jet device  90  of FIG. 9, there is provided a water exit channel  91  separate from the yarn passage  55  to facilitate water removal. 
     Referring now to FIGS. 10 and 11, there is shown a liquid jet device  100  in the form of a cylindrical housing  101  having an insert  102  in which there is a bore  55  defining an axial path for the yarn  13  to pass through the jet  100 . The bore  55  may be conical as bore  74  of FIG. 7 or stepped as bore  81  of FIG.  8 . Water or other suitable liquid is supplied in the direction of arrow A to the annular space  106  between the housing  101  and the insert  102 . In the insert  102  are water channels  108  which are tangential to the bore  55 , two such water channels  108  being shown in this case symmetrically disposed around the yarn  13 . The water channels  108 , being offset from the axis of the bore  55 , provide that the impinging jets of water subject the yarn  13  to a torque, which false twists the yarn  13 . The water channels  108 , which may be straight as shown or may be formed spirally in the insert  102 , are directed at an angle to the direction of running of the yarn  13  so that the water jets have components of velocity along the path of the yarn  13  as well as laterally thereof. This applies a forwarding force to the yarn  13  as well as the false twisting torque. The greater the cone angle C, the more is the twisting torque and the less is the forwarding force and vice versa. The water may exit from the insert  102  in the direction of arrow B through an outlet  103  if provided. More than one such water outlets  102  may be provided, each substantially in alignment with one of the water channels  108 . 
     In FIG. 12 there is shown a miniature twist jet  120  that operates in a similar manner to jet  100 . In this case an insert  121  is located in a housing  122 . The insert  121  has a conical end  123  that co-operates with a conical end  124  to the bore  125  of the housing  122 . In the conical end  123  of the insert  121  are one or more grooves  126  forming a water channel. Water is introduced into the housing  122  through inlet  127 , and passes to an annular space  128  between the insert  121  and the bore  125 . The water then flows through the water channel or channels  126  to impinge on the yarn  13  as it passes through the jet device  120 . 
     Referring now to FIG. 13, there is shown a multi-head false twist unit  130 . Within a housing  131  are three axially aligned liquid jet devices  132  similar to the type shown in FIG.  12  and mounted in a casing  133 . Water is introduced to each of the jets  132  through the casing  133  and housing  131  by high-pressure inlets  134 . The water, having impinged on the yarn  13  running successively through the three jet devices  132 , exits from the housing  131  through drain holes  135  into the annular space  136  between the casing  133  and the housing  131 . Water outlets  137  are provided in the housing  131 . The use of the multi-head apparatus  30  provides that each successive jet device  32  augments the twist in the yarn  14  inserted by the previous jet device  32 . The cone angles of the cones  17  of the three jet devices  32  may be progressively smaller whereby the first jet device  32  imparts more twisting torque and less forwarding force and the later jet devices  32  impart successively less twisting torque and greater forwarding force to the yarn  14 . 
     A conventional false twist texturing machine arrangement  140  is shown in FIG.  14 . Typically the yarn  13  is partially drawn and is supplied on supply packages  142  mounted in a creel  143 . The yarns  13  are withdrawn from the packages  142  by a first feed roller pair  144  and fed to a primary heater  145 , and then around a guide roller  146  to a cooling device  147 . From the cooling device  147  the yarn  13  passes through a false twist device  148  and a second feed roller pair  149 . The false twist device  148  imparts a false twist to the yarn  13  which twist runs back to the first feed rollers  144 , these acting as a twist stop device. The heating device  145  heats the twisted yarn  13 , which retains the twist memory as it is cooled in the cooling device  147 . The thus textured stretch yarn  13  may be passed directly to a take up arrangement  141  in which it is wound onto a bobbin  150  driven by surface contact with a driving bowl  151 . Alternatively the textured yarn  13  may be passed through a setting or second heater  152  to become set yarn before passing to the take-up arrangement  141 . In this case, a third feed roller pair  153 , which forwards the set yarn  13  to the take-up arrangement  141 , is driven at a lower peripheral speed than that of the second feed rollers  149  so that the heating of the textured yarn  13  in the second heater  152  is at a controlled overfeed. 
     In the case of this invention, the false twisting device  148  is constructed and operates as the device  50 ,  70 ,  80 ,  90 ,  100 ,  120  or  130  as described above, with water being introduced into the false twist device  148  in the direction of arrow A. The cooling device  147  is a cylinder through which the heated yarn  13  passes and into which cooling water is introduced in the direction of arrow D and from which the water exits in the direction of arrow E. With this arrangement, the cooling water passes along the cooling device  147  in turbulent contraflow to the running yarn  13 , both of which factors enhance the transfer of heat from the yarn  13  to the cooling water. At the opposed ends of the cooling device  147 , the yarn inlet and yarn outlet are provided with labyrinth seals  154  which can be pressurised against escape of water, for example by compressed air. 
     Conventionally, the heater  145  is a relatively long plate at a temperature close to the melting temperature of the yarn  13  and in contact with which the yarn  13  runs. Alternatively, to reduce the overall size of the machine  140 , the primary heater may be a short non-contact heater at a temperature considerably higher than the melting temperature of the yarn  13 . As an alterative the roller  146  may be heated in order to heat the yarn  13  as it passes therearound. However, in this case the primary heater  145  is a vapour-heating chamber through which the yarn  13  runs, the preferred vapour being pressure steam. A further roller  155  is disposed to combine with the guide roller  146  to form the twist stop that inhibits twist from running upstream of the rollers  146 ,  155 . The untwisted yarn  13  is more receptive to heat transfer than twisted yarn, so that the heater  145  may be smaller than even the short high temperature heaters referred to above. The peripheral speed of the rollers  146 ,  155  is greater than that of the first feed rollers  144  so that the heated yarn  13  is drawn between them. The yarn  13  is heated sufficiently by the steam in heater  145  prior to passing through the twist stop rollers  146 ,  155  that no further heating is required between the twist stop rollers  146 ,  155  and the false twist device  148 . The heat in the yarn  13  is sufficient as it passes into the cooling device  147  for the yarn  13  to retain its twist memory. Due to the turbulent contraflow of cooling liquid in the cooling device  147 , this cooling device  147  is shorter than conventional free-air or plate contact cooling arrangements. 
     Referring now to FIGS. 15 and 16, there is shown an all-in-one jet device  160 . The jet device  160  fulfils the role of the heater  145 , cooling device  147  and false twist device  148  of the machine  140  described above. 
     The primary heating, cooling and false twisting device  160  comprises a housing  162  having labyrinth seals  163  at the entrance and exit for the yarn  13 . The labyrinth seals  163  are pressurised, to prevent water egress from the interior of the housing  162 , by compressed air supplied through inlets  161 . Within the housing  162  is, in sequence, a primary heating apparatus  164  and a cooling and twisting apparatus  165 . The heating apparatus  164  has a steam inlet  166  and a steam outlet  167 , the yarn  13  being heated by the steam as it passes along the heating chamber  168  of the heating apparatus  164 . A manifold  169  surrounds the heating chamber  168  to provide supplementary heating, the manifold  169  being supplied through inlet  170 . A supplementary heater  171  may be provided in the steam inlet  170  to ensure the maximum heating of the yarn  13  in the heater  164 , thereby reducing the length of heater  164  required. The cooling and false twisting device  165  shown is a single head apparatus such as devices  50 ,  70 ,  80 ,  90 ,  100  or  120  described above, but preferably a multi-head apparatus  130  as shown in FIG. 13 is provided in order to increase the twist level imparted to the yarn  13 . As the heated yarn  13  passes into the cooling and false twisting device  165  it is cooled due to the effect of the cold water passing through the device  165 . The jets of water impinging laterally on the yarn  13  impart a false twist to the yarn  13 . The water passes out of the cooling and false twisting device  165  through a water drain  172 . This twist runs back through the heating apparatus  164  to the first feed rollers  144 , these acting as a twist stop device. The heating device  164  heats the twisted yarn  13 , which retains the twist memory as it is cooled in the cooling and twisting device  165 . A further labyrinth seal  161  may be provided between the heating device  164  and the cooling and twisting device  165  if required. 
     Referring now to FIG. 17, there is shown a false twist texturing machine  180  having many of the components as described in respect of machine  140  of FIG.  14 . The corresponding components are identified by the same reference numerals. In this arrangement, heating for drawing the yarn  13  between the first feed rollers  144  and the rollers  146 ,  155  is provided by a heated draw pin  181 . The heating, cooling and false twisting device  160  has labyrinth seals  163  at the entrance and exit for the yarn  13 , the seals  163  being pressurised to prevent water egress from the interior of the housing  162 , by compressed air supplied in the direction of arrows C. Within the housing  162  is, in sequence, a heating apparatus  164  and a cooling and twisting apparatus  165 . The heating apparatus  164  has a steam inlet  166  and a steam outlet  167 , the yarn  13  being heated by the steam as it passes through the heating apparatus  164 . The cooling and false twisting apparatus  165  shown is a single head device such as devices  50 ,  70 ,  80 ,  90 ,  100  or  120  described above, but preferably a multi-head apparatus  130  as shown in FIG. 13 is provided in order to increase the twist level imparted to the yarn  13 . As the heated yarn  13  passes into the cooling and false twisting apparatus  165  it is firstly cooled, due to the effect of the cold water passing through the apparatus  165 . The jets of water impinging laterally on the yarn  13  impart a false twist to the yarn  41 . This twist runs back through the heating apparatus  164  to the feed rollers  146 ,  155 , these acting as a twist stop device. The heating device  164  heats the twisted yarn  13 , which retains the twist memory as it is cooled in the cooling and twisting device  165 . 
     Another significant difference between the machines  140  and  18  is that in the case of machine  180  there is shown a measuring instrument  182  which measures a property of the stretch yarn  13 . Such parameter may be elasticity or crimp modulus. The measuring instrument  182  sends a signal proportional to the value of the measured parameter to a controller  183  which compares that value with a predetermined desired value. If there is a discrepancy between the two values the controller  183  is operable to control the rate and pressure of the water flow to the false twist apparatus  165 , the speed of the feed rollers  144 ,  146 ,  155 ,  149  and/or the temperature of the heating apparatus  164 . The machine  180  may have a second post treatment or setting heater  152  as shown in FIG.  14 . The textured yarn  13  runs through the secondary heater  152  under controlled overfeed conditions between second feed rollers  149  and third feed rollers  153  to receive its setting heating. The set yarn  13  then passes to the take-up arrangement  141 . The steam issuing from the primary heater  164  is passed to the secondary heater  152 , being further heated or cooled as required under the control of the controller  183  in response to the signal from the measuring instrument  182  which in this case measures a parameter of the set yarn  13 . 
     Although the embodiments of false twisting apparatus shown are fixed units, the individual jets of water may be individually mounted in the housing so that each is adjustable in respect of its spacing from the axis of the yarn  13  to increase or decrease the twisting torque provided by a specific size of jet of water. 
     In FIG. 18, there is shown a texturing slot jet device  190  in the form of a cylindrical housing  191  having a texturing chamber  192  defining an axial path for a multifilament yarn or yarn product  13  to pass through the jet  190 . Opening into the texturing chamber  192  are inlets  194 , two being shown in this case disposed around the yarn product  13 , for water or other suitable liquid provided from a source (not shown). Aligned with each inlet  194  on the opposite side of the texturing chamber  192  is a resonance chamber  193 . The openings of the inlets  194  are transverse to the axis of the texturing chamber  192  so that the impinging jets of water are transverse to the running yarn product  13  and subject the yarn product  13  to an agitating force. The inlets  194  are directed at an angle to the direction of running of the yarn product  13  so that the water jets have components of velocity axially of the yarn product  13  as well as transversely thereof. This applies a forwarding force to the yarn product  13  as well as the transverse force. Alternatively the inlets  194  could be inclined in the reverse direction to apply a retarding force to the yarn product  13 . The supply of water to the inlets  194  may be pulsed to produce a more even form of texturing or other desired effect. At each end of the housing  191  is an annular labyrinth seal  195  to prevent escape of water from the texturing chamber  192  along the path of the yarn product  13 , the water exiting from the texturing chamber  192  through a water drain  196 . The seals  195  may be pressurised by gas, e.g. compressed air, from a source (not shown) through inlets  197 . 
     FIG. 19 shows a three hole intermingling jet device  200  to which two yarns  13   a,    13   b  are introduced to form a single intermingled/textured yarn  13 . The jet device  200  is formed from a block  201  having a conical entry  202  for the yarns  13 ′,  13 ″. The entry  202  leads to an intermingling chamber  203  into which the three water jets  204  are directed. The jets  204  impinge substantially axially on the combined yarns  13  to intermingle/texture their filaments or fibres. After the intermingling, the water passes from the jet device  200  through radial drain outlets  205 . The yarn  13  is forwarded to a baffle plate  206  at which it is retarded and redirected to pass from the jet device  200  in a radial direction. The retardation reduces the tension in the yarn  13  to assist in allowing a good level of intermingling to occur. Since some water will be entrained with the yarn  13 , forward drains  207  are provided in the baffle plate  206 . To reduce the insertion of twist, an even number of water jets  204  are more suitable than the three hole version of FIG.  19 . Suitable arrangements are shown in cross section in FIG. 20, in which four water jets  204  are provided. The cross section of the intermingling/texturing chamber  203  may be circular or square as shown. 
     As an alternative to the change of direction of the yarn  13  at the baffle plate  206  of the previous embodiment, the yarn  13  may be retarded by being formed into a plug as shown in FIG.  21 . In this embodiment, the texturing/intermingling jet  210  is similar to jet device  200  up to the texturing/intermingling chamber  203  to which two yarns  13 ′,  13 ″, for example a core yarn  13 ′ and an effect yarn  13 ″, are forwarded. However, after texturing/intermingling, the yarn  43  passes through the end plate  207  into a plug former  208 . In the plug former  208  the forward motion of the yarn  13  is resisted by the mass of yarn  13  already accumulated in the forward former  208 . By this means, the forward thrust of the jet  210 , which creates a high yarn tension in the jet  210 , is reduced to zero, and high tensions are inimical to obtaining good interlacing and loop locking. Water is more efficient than air in both forwarding the yarn  13  and intermingling. Achieving the proper balance between the two functions is important. 
     Referring now to FIG. 22, there is shown a filament spinning apparatus  220  having a spinning head  221  from which filaments  222  are extruded. The filaments  222  are withdrawn from the spinning head  221  by a first feed roller  223 . Spin finish oil is applied to the filaments  222  by an oil applicator  226 , at which the filaments  222  are brought together to form yarns  224 , and the regularity of the oil application is improved by oil dispersion jets  227 . The yarns  224  are drawn between the spinning head  221  and the first feed roller  223 , and the resulting partially oriented yarn  228  is forwarded to a second feed roller  229 . An intermingling jet  236 , which directs a jet of liquid at the yarn  228  to intermingle the filaments of the yarn  228 , is disposed in the controlled tension zone between the first and second feed rollers  223 ,  229 , but may be placed before the roller  223 . The interlaced yarn  230  is passed through an optical interlace sensor  237  to a forwarding point  231 . The interlaced partially drawn yarn  230  is then fed from the forwarding point  231  to a take up zone  232  to be wound using a traverse guide  233  onto a package  234  driven by surface contact with a driving bowl  235 . The traverse guide  233  reciprocates as shown along a path parallel with the axis of the package  234 . The interlace sensor  237  comprises an optical transmitter  238  and an optical receiver  239 , a beam from the transmitter  238  being directed at the yarn  230  and then being received by the receiver  239 . The receiver  239  sends to a control device  240  a signal that varies in response to the changes in dimension of the intermingled yarn  230 , i.e. as interlace nodes pass the sensor  238 . The control device  240  is operable to control the supply and/or pressure of liquid to the intermingling jet  236  and/or the speed of the feed rollers  223 ,  229 , and that supply may be pulsed if desired. 
     In the case of this invention, the intermingling jet  236  is constructed and operates as the device  190 ,  200  or  210  of FIGS. 18 to  21 , with water being introduced into the intermingling jet  236  in the direction of arrows A as described above. Conventionally, the distance between the spinning head  221  and the first feed roller  223 , the cooling chimney, is a relatively long so that the yarns  224  have cooled to a temperature at which they can be subjected to the intermingling step in the jet  236 . However, since the water supplied to the jet  236  is cold, thereby cooling the drawn yarn  228 , this may provide sufficient cooling for a significant reduction in the height of the cooling chimney whilst allowing the satisfactory intermingling of the filaments of the yarn  228  by the jet  236 . Alternatively, a further cooling device  241  may be placed in the threadline between the feed roller  223  and the intermingling jet  236 . The cooling device  241  is a cylinder through which the yarn  228  passes and into which cooling water is introduced in the direction of arrow D and from which the water exits in the direction of arrow E. With this arrangement, the cooling water passes along the cooling device  241  in turbulent contraflow to the running yarn  228 , both of which factors enhance the heat transfer from the yarn  228  to the cooling water. At the opposed ends of the cooling device  241 , the yarn inlet and yarn outlet are provided with labyrinth seals  242  which can be pressurised against escape of water therethrough as described in respect of seals  195  of the texturing jet  190 . The intermingling jet  236  and the cooling device  241  are shown as contiguous, and the cooling water may pass directly from one to the other. As a further alterative, and provided that the tension in the yarns  224  is not too great, the cooling device  241  and intermingling jet  236  may be disposed between the oil dispersion jets  227  and the first feed roller  223  to further reduce the height of the cooling chimney, as shown in machine  243  in FIG.  23 . Only one of the yarns  224  is shown passing through the respective cooling device  241  and intermingling jet  236  for clarity. 
     A machine  250  for co-mingling two or more yarns is shown in FIG. 24, in this case two textile yarns  251 ,  252 . The yarns  251 ,  252 , which may be the same as but are more usually different from each other, for example one may be a staple yarn, are supplied on respective supply packages  253 ,  254  mounted in a creel  255 . The yarns  251 ,  252  are withdrawn from the packages  253 ,  254  by first feed roller pairs  256 ,  257  and fed along parallel tracks to respective heated rollers or draw pins  258 ,  259  to respective draw rollers  260 ,  261  and to a cooling device  262 . From the cooling device  262  the yarns  251 ,  252  pass through a co-mingling device  263  to a second feed roller pair  264 . The peripheral speed of the draw rollers  260 ,  261  is greater than that of the first feed rollers  256 ,  257  so that the yarns  251 ,  252  are drawn at the draw rollers or pins  258 ,  259 , and the peripheral speed of the second feed rollers  264  is controlled relative to that of the draw rollers  260 ,  261  so that the tension in the yarns  251 ,  252  is controlled for satisfactory co-mingling of the yarns  251 ,  252 . The yarns  251 ,  252  may be drawn to differing amounts, or one of the yarns may be forwarded directly from the feed rollers  256 ,  257  to the co-mingling device  263  so as not to be heated, drawn and cooled, as required in any particular application. Also either or both of the yarns  251 ,  252  may be false twisted, for example one S-twist and one Z-twist, between the feed rollers  256 ,  257  and the co-mingling device  263 . The co-mingling device  263  agitates the yarns  251 ,  252  to co-mingle their filaments together to form a single coherent yarn  265 . The heated rollers  258 ,  259  heat the yarns  251 ,  252  to facilitate the drawing step and any false twisting step. The thus co-mingled yarn  265  is forwarded to a take up arrangement  266  in which it is wound onto a bobbin  267  driven by surface contact with a driving bowl  268 . 
     In this machine arrangement, the cooling device  262  and the commingling device  263  are shown to be contiguous. In addition, the water introduced into the co-mingling device  263  is forwarded therefrom to the cooling device  262  in the direction of arrow D, so that both devices  263 ,  262  use the same water. Also in the case of machine  250 , there is shown a measuring instrument  269 , which measures a property of the co-mingled yarn  265 . Such parameter may be node frequency or coherence. The measuring instrument  269  sends a signal proportional to the value of the measured parameter to a controller  270  which compares that value with a predetermined desired value. If there is a discrepancy between the two values the controller  270  is operable to control the rate or pressure of water flow to the co-mingling device  263  and/or the speed of the first feed rollers  256 ,  257 , the draw rollers  260 ,  261 , and the second feed rollers  264 . 
     Referring now to FIG. 25, there is shown a drafting and twisting jet device  270  for staple products. In staple spinning it is necessary to twist and draw the sliver or roving simultaneously so as to reduce the number of fibres in the yarn cross section by drawing but to maintain the integrity of the yarn by the twist insertion. The jet device  270  is suitable for this purpose, and consists of a block  271  having labyrinth chambers  272  at the inlet for the sliver or roving  273 . High pressure water is passed into the bore  275  of the jet device  270  through an inlet  276  and drains from the bore  275  through drain outlet  277 . Labyrinth seals  278  are disposed along the path of the spun yarn  279  formed by the drawing and twisting effect of the water on the sliver or roving  273 . To prevent water egress from the jet device  270  in the direction of the sliver or roving entry or spun yarn withdrawal, compressed air is passed into the labyrinth chambers  272  through inlet  274  and into at least the last of the labyrinth seals  278  through inlet  280 . 
     A staple twisting and drawing machine arrangement  290  embodying the above-described twisting device  270  is shown in FIG.  26 . The supply of staple product  273  is provided in this case on a supply package  291 , but the supply could be directly from a carding machine or other processing machine (not shown). A first feed roller pair  292  withdraws the product  273  from the package  291 . The product  273  is then forwarded to a drawing and twisting device  270 . From the drawing and twisting device  270  the resulting spun yarn  279  passes via a second feed roller pair  293  to a take up arrangement  294  in which it is wound onto a bobbin  295  driven by surface contact with a driving bowl  296 . The twist device  270  imparts a false twist to the product  273  which twist traps the staple fibres to give coherence to the spun yarn  279 . 
     A measuring instrument  297  is provided to measure a property of the spun yarn  279 . Such parameter may be bulk or hairiness. The measuring instrument  297  sends a signal proportional to the value of the measured parameter to a controller  298  which compares that value with a predetermined desired value. If there is a discrepancy between the two values, the controller  298  is operable to control the rate and/or pressure of the water flow to the twisting device  270 , and/or the speed of the feed rollers  292  and  293 .