EP1573110B1 - Device for finishing denim woven fabric - Google Patents

Abstract

A device for finishing woven denim textiles is described which, proceeding from unfinished goods, is supposed to be brought to predetermined reference values for finished width, skew and woof thread density. The device is supposed to be designed for continuous operation for regulating all three reference values. According to the invention, a stretching device, such as a rack or a loop dryer, and a shrinkage system for continuous throughput of the woven denim textile, are arranged one after the other. Directly behind the stretching device, particularly, at the same time, behind the shrinkage system, a single measuring device, preferably as an optical detector having a digital camera, is provided. The measuring device is designed, at the same time, for detecting the actual values of finished width, skew and woof thread density, and is supposed to be connected, in control circuits, with devices for achieving the reference values.

Description

The invention relates to a device for equipping a denim fabric, which - starting from a raw material - is to be brought to predetermined target values of finished width, skew and weft density, with an expander, e.g. Hoist or Hotflue, which are associated with both extender for pulling the fabric and skew means for applying a skew, and with a continuous operation associated, preferably downstream, Krumpfanlage with compression means for adjusting a weft thread density. Such a device is also referred to as a denim equipment line.

The denim process chain in the manufacture of denim garments, e.g. so-called jeans, starting from the raw fabric includes the so-called denim finishing - also called fabric equipment. These include drying, longitudinal stretching and the so-called skew stretching as well as the shrinkage-making the fabric. In the aforementioned Schrägrecken (English: skewing), the fabric is pulled diagonally with respect to warp and weft (skew). For this purpose, special Schrägereckwerke be used in practice.

Denim raw material is usually produced with a raw width, eg 162 cm, which is significantly larger than the finished width, eg 151 cm. To get the finished width, the raw material is pulled out. The thereby reduced weft thread density (number of threads per unit length) is then during upsetting of the web in a Krumpfanlage - especially with Gummibandkrumpfaggregat as Core machine - brought to the desired value. A measuring and control method with which the desired value of the shrinkage to be achieved is determined and given as a controlled variable the Gummibandkrumpfaggregat is out DE 43 23 715 A1 known. The residual shrinkage and the thread density per centimeter are directly dependent on one another for a given quality, ie if one knows the thread density at the exit of the finishing line, the residual shrinkage value is also given.

The pulling of a denim fabric web can be done in a conventional, a plurality of upper and lower rollers having stretching unit or, for example, in a loop dryer - Hotflue - if the latter has corresponding longitudinal stretching means. A suitable hotflue is described in DE 33 36 328 C2 , It comprises an upper series and a lower series of guide rollers. The two Leitwalzenserien are stored in the known parallel to each other and horizontally - essentially in one plane - in a housing. The housing has in a inlet wall a horizontal inlet slot through which the fabric to be treated is spread out; accordingly there is an outlet slot in an outlet wall.

The (straight) connecting line between the inlet and outlet slots defines the central transport direction of the fabric in the hotflue. In fact, however, the fabric web is transported in a loop or meander shape alternately over a lower and an upper guide roller. Within the housing arranged parallel to the guide rollers tuyeres are provided, with the aid of treatment means, in particular heated air - to blow in general - circulating air - on the fabric or in the clamped fabric loops.

The fabric is kept within the Hotflue - with the help of the dryer upstream and trailing web tension means - below a predetermined fabric web tension. This longitudinal tension should be at least so great that even with a goods content of thirty or more fabric meters a substantially wrinkle-free fabric flow within the Hotflue is guaranteed.

The aforementioned skew of the weft threads, which is a significantly different from 90 ° oblique position of the weft threads relative to the warp threads of the fabric, is achieved when using a conventional stretching unit, for example by tilting a portion of the stretching rollers. Most of the upper stretching rollers are raised on one side (at one longitudinal end) vertically or lowered the lower rollers on one side vertically.

As a tilting means for generating a skew delay has also been proposed (not previously published German patent applications 102 34 799.9 of 31 July 2002 ), provide for Denimware a Hotflue, the means for exerting a Längszugs - ie stretching means - upstream and downstream and in the housing at least a group of at least one Leitwalzenserie can be tilted in one direction in one direction. The core of the associated knowledge is that only by tilting at least a portion of the guide rollers of Hotflue a separate skew device is completely save. The tilting of the guide rollers does not affect the otherwise normally expected performance of the Hotflue.

An apparatus for equipping a denim fabric with an expansion device, which are associated with extender for pulling the fabric web, and with a downstream in continuous operation Krumpfanlage with compression means for adjusting a weft yarn density is off US Pat. No. 3,691,600 known. This known device is provided with a measuring device for detecting the longitudinal shrinkage of the fabric web.

The invention has for its object to summarize in a plant an expansion device, such as horizontal bar or a Hotflue with connected spreader field (for adjusting the width of goods), and a Grummibandkrumpfaggregat (as a core machine for an adjustable longitudinal shrinkage) and to control the system so that for Residual shrinkage, skew delay and width decisive for the loss of goods remain reproducibly constant. In other words, it should be achieved in the combined system that during the furnishing of denim fabric predetermined target values of fabric width, skew and weft yarn density can be obtained continuously in one go.

The solution according to the invention is given for the device mentioned in the characterizing part of claim 1. Some improvements and further developments of the invention are described in the subclaims.

The device for finishing denim fabric starting from a raw material preferably comprises a stretching device or a hotflue as the stretching device, wherein the stretching device is associated with both draw means for pulling the fabric and skew means for applying skew, and a continuous feed operation with upsetting means for Setting a (in particular a given) thread density. According to the invention, the device comprises a single measuring device for detecting the actual values of fabric width, skew and weft density, which is in control in each case in control connection with the stretching and inclining means of the stretching device on the one hand and the compression means of Krumpfanlage on the other hand for adjusting the respective target values ,

Preferably, the meter of the stretching device (ie in particular the stretching unit or the spreader field of the Hotflue) or the Krumpfanlage should be followed immediately. "Immediately downstream" here means that the fabric supply between the device to be controlled (stretching unit or Hotflue or Krumpfanlage) and the meter should be minimal in order to keep the amount of up to the switching of the control loop imperfectly treated goods small. The least loss of material in this sense, however, is to be expected if the meter is also the first fabric equipment stage - in general so the Reckwerk or the Hotflue - is preceded. Between the device to be controlled and the measuring device, aids, e.g. Web tension controller, are arranged.

By the invention it is achieved that the desired values of fabric width, skew and weft yarn density in one go using a suitably trained system or a properly trained Hotflue and a Krumpfanlage and a single meter with continuous onward transport of the equipment in the usual manner equipped To achieve denim fabric is.

In a first step, the fabric width (at the expense of weft yarn density) and the skew of the weft yarns are set to a predetermined target value. In the continuously following second step, the weft yarn density previously reduced (during longitudinal stretching) is likewise brought to a predetermined desired value in the shrinking plant. Both steps are controlled according to the invention with the help of one and the same meter.

In the context of the invention is preferably used as a measuring device, an optical detector with digital camera, which can detect the thread density, the skew delay and the width of goods. The detector should be performed traversing in his measuring and control work transversely to the transport direction of the fabric to achieve that he can also register the width of the fabric, the amount of skew and the weft density and enter into the associated control loop.

1. a) rückwärts auf einen Mechanismus, der gegebenenfalls entweder die obere oder die untere Walzenreihe des Reckwerks oder der Hotflue schrägstellt,
2. b) rückwärts auf den Druckgeber eines z.B. pneumatisch betätigten Pendels oder den Sollwertsteller einer Bahnkraftregelanlage der Dehneinrichtung, welche im Zusammenspiel mit einer angetriebenen Zugwalze die Warenspannung beim Durchlaufen durch die Dehneinrichtung vergrößern oder verkleinern, so daß die Breite dadurch geändert werden kann, und
3. c) vorwärts auf den Stellmotor der Anpreßwalze des Gummibandkrumpfaggregates, damit durch Verändern der Gummibandanpressung der vorgegebene Warenschrumpf erzielt wird.

If the measuring device of the stretching device is connected upstream of the shrinking device, however, the following control pulses (for setting the respective setpoint values) are to emanate from it, for example from the digital camera with optical detector

1. a) backwards to a mechanism which, if appropriate, tilts either the upper or the lower row of rolls of the drawbar or the hotflue,
2. b) backwards to the pressure transducer of a pneumatically actuated pendulum or the setpoint adjuster of a web tension control system of the expansion device, which increase or decrease the goods tension when passing through the stretching device in interaction with a driven tension roller, so that the width can be changed, and
3. c) forward to the servo motor of the pressure roller of Gummibandkrumpfaggregates so that by changing the Gummibandanpressung the predetermined shrinkage is achieved.

If the measuring instrument is positioned on the fabric in front of the stretching device and before the shrinking system, all three parameters must be regulated forward. It is also within the scope of the invention, the meter at the end of the equipment line so following the Krumpfanlage, even immediately before winding, panels or the like, to install, so that the three parameters described above are all regulated backwards.

Fig. 1

eine erfindungsgemäße Gesamtanlage im vertikalen Längsschnitt; und

Fig. 2

einen Schnitt längs der Linie II-II von Fig. 1.

Details of the invention will be explained with reference to the schematic representation of an embodiment with a Hotflue as an expander. Show it

Fig. 1

an overall system according to the invention in vertical longitudinal section; and

Fig. 2

a section along the line II-II of Fig. 1st

According to FIG. 1, a denim material web 1 from roll 2 in the transport direction 3 is guided by a first tensioning means 4 into a hotflue with housing 6 designated as a whole by 5. The housing 6 has a substantially horizontal inlet slot 7 with guide roller 8 and inside two series 9 of guide rollers 11 to the guide rollers 11, the fabric web 1 is guided in meandering loops upwards and downwards and finally via a guide roller 12 through an outlet slot 13 of the housing 6 passed to a second clamping means 14. Within the housing 6 16 directed blowing nozzles 17 are provided in the - between each pair of guide rollers 11 of a series of rolls 9 clamped - fabric loops. The longitudinal tension to be applied to the material web 1 within the hot-run 5 is adjusted between the two tensioning means 4 and 14 - in the direction of the central transport direction 18 of the material web 1 - by means of a longitudinal tension control device 19.

In the embodiment of FIGS. 1 and 2, the upper guide rollers 11 are set at one of its longitudinal ends 21 in spherical bearings 22 and at the other of its longitudinal ends 23 mounted on a beam 24 which - as shown in FIGS. 1 and 2 - at its one longitudinal end of the 25th is held in a tilting bearing 26 and the other (in Bahntransportrichtung 2 subsequent) longitudinal end 27 on a tilting device 28 is resting. The latter is assigned a tilt control unit 29. In the transport direction 3 comes first the tilting bearing 26 and the longitudinal end 27 with the tilt actuator.

In the transport direction 3, the measuring device 14 according to FIG. 1 is adjoined directly by a measuring device 30 according to the invention. In the transport direction 3 follows a Krumpfanlage 31 with shrinkage control device 32 and compression means 33. Finally, the finished fabric can be wound on a roll 35 via a voltage regulator 34.

In the measuring device 30, which is preferably to be formed as an optical detector with digital camera, the fabric width, the skew and the weft yarn density are determined. The device cost remains relatively low, if the measuring device 30 transversely to the transport direction 2 of the fabric 1, e.g. at a transversely to the transport direction 3 arranged rail traversing. In appropriately defined controlled reciprocating measuring head, it is possible in a relatively simple manner, almost continuously measured in the Hotflue 5 (from the first clamping means 4 to the second clamping means 14) achieved actual values of fabric width, skew and weft thread density. The values thus determined in the measuring device 30 are fed to the control devices 19 and 29 (longitudinal tension and skew delay) and to the shrinkage control device 32 along the dashed lines of action such that a corresponding control loop is created for adjusting predetermined target values.

According to Fig. 1, the meter 30 of the Krumpfanlage 31 is connected upstream. Alternatively, the meter can be followed by the Krumpfanlage. As an example, such a measuring device 30 ', which is preferably formed as well as the measuring device 30, shown in phantom in Fig. 1. The associated control lines - connections to the control units 19, 29 and 32 - are characterized by dotted lines of action.

In another preferred alternative, meter 30 "is placed in front of even the first stage of equipment, e.g., the hotflue., The loss of misfed web trunking can then be kept very low, and the lines of action associated with the position of meter 30" are shown in phantom.

LIST OF REFERENCE NUMBERS

1 =

Denim fabric

2 =

role

3 =

transport direction

4 =

first clamping device

5 =

hotflue

6 =

Housing (5)

7 =

Inlet slot (6)

8 =

deflecting

9 =

Leitwalzenserie

11 =

guide roll

12 =

deflecting

13 =

outlet slot

14 =

second clamping device

16 =

Fabric loop

17 =

nozzles

18 =

middle transport direction

19 =

Longitudinal tension controller

21 =

1st longitudinal end (10)

22 =

Spherical bearings (21)

23 =

2nd longitudinal end (10)

24 =

bar

25 =

1st longitudinal end (24)

26 =

rocker bearing

27 =

2nd longitudinal end (24)

28 =

Tilt device

29 =

Tilt controller

30,30 '=

gauge

31 =

shrinking

32 =

Krumpf controller

33 =

upsetting means

34 =

voltage regulators

35 =

role

Claims (6)

1. Device for finishing a denim textile web (1) which, proceeding from unfinished material, is required to reach predetermined reference values for the finished width, skew and weft thread density, comprising a stretching device, e.g. a rack or hot flue (5), to which both stretching means (4, 14) for pulling the textile web (1) lengthwise and skew positioning means (28) for applying skew are assigned, and comprising a shrinking unit (31), which is in continuous operation, arranged in particular downstream and comprises compression means (33) for adjusting the weft thread density, characterised by a single measuring device (30) for detecting the actual values of material width, skew and weft thread density, which device is connected in a control circuit to control the stretching and skewing means (4, 14; 28) of the stretching device on the one hand, and the compression means (33) of the shrinking unit (31) on the other hand to achieve the respective reference values.
2. Device according to claim 1, characterised in that the measuring device (30) is assigned to the textile web (1) before the first finishing stage, in particular in front of the stretching device (5).
3. Device according to claim 1 or 2, characterised in that the measuring device (30) is connected downstream of at least the stretching device (5).
4. Device according to at least one of claims 1 to 3, characterised in that the measuring device (30) is connected downstream of the stretching device (5) and the shrinking unit (31).
5. Device according to at least one of claims 1 to 4, characterised by an optical detector with a digital camera as the measuring device (30).
6. Device according to at least one of claims 1 to 4 with a hot flue (5), in which the textile web (1) is guided up and down over a lower and upper series (9) of guide rollers (11) in meandering loops, characterised in that one of the series of rollers (9) is mounted on one side on a beam (24), and in that the beam (24) rests on a tilt bearing (26) with its first longitudinal end (25) and on a lifting device (28) for raising and lowering the beam end (27) in a controlled manner with its second longitudinal end (27) following in web transport direction (3).

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