EP1660709B1 - Method for compressive shrinking and rubber blanket shrinking system - Google Patents

Abstract

This plant is used to treat textile webs (9) which do not fully cover the width of the cloth belt (3) and of the cylinder (1). This leaves inactive regions of the belt at its edges, which may be subjected to greater heating. Such regions are separately and more strongly cooled than the active regions (27) of coverage, after lifting-off the main cylinder. An independent claim is included for the corresponding pre-shrinkage plant for textiles.

Description

The invention relates to a method for the compressive shrinkage of a textile fabric web by means of a compressive or blanket shrinking plant, in which a mechanically compressed fabric web between an endless blanket and the lateral surface of a heated master cylinder or heating cylinder is fixed and in which each of the master cylinder running area of the blanket is cooled. It further relates to a blanket-Krumpfanlage, in which a mechanically compressed fabric between an endless blanket and the lateral surface of a heated master cylinder is to be fixed and in which each of the main cylinder expiring region of the blanket coolant are assigned. The blanket is also referred to as a rubber band or -mitläufer.

Blanket-Krumpfanlagen with so-called blanket calender are described in DE-AS 10 72 220 , The master cylinder of a Krompressiv Krumpfzylinders is heated when crumpling cotton fabric to about 130 ° C, to fix the mechanical compression of the respective fabric. The heat supplied by the master cylinder heats not only the fabric itself but also the blanket pressing the fabric against the master cylinder. Since the width of the fabric varies, at least from batch to batch, the blanket will generally be wider than the treated fabric.

Due to the heat effect of the master cylinder, the blanket is heated so much that existing in the blanket plasticizer migrate to the outside (migrate). To slow this effect, the blanket in the conventional Krumpfanlagen after draining the master cylinder and lifting the fixed Goods or fabric web cooled over its entire width with water (see, for example, the above DE-AS 10 72 220 ).

When running on the master cylinder covered by the fabric (middle) areas are heated less than the respective areas of the blanket not touched by the fabric. The inventors have recognized that the conventional cooling in the edge regions of the blanket is not always sufficient, so that these edge regions can be prematurely brittle. To overcome this problem, you can not cool the blanket but more, because when too cold blanket a proper fixing of the mechanical compression of the fabric does not occur. In practice, it was therefore to be accepted that the blanket becomes brittle due to the heating of its surface and relatively often - in continuous operation about every two weeks - must be sanded. With each sanding, the originally order of magnitude 5-8 cm thick blanket becomes thinner, with the thickness of the cloth decreases its Krumpfpotential.

The invention has for its object to meet in the blanket calender a compressive Krumpfanlage the premature wear of each of the fabric web not covered areas of the blanket; Without the respective active areas of the blanket, that is, the blanket areas covered by the fabric during operation on the main cylinder, to be cooled impermissibly. In other words, means are sought for preventing premature brittleness of the edge regions of the blanket located outside the web width.

The solution according to the invention is specified for the method mentioned in the characterizing part of claim 1. It consists in particular in that when applied to a rubber blanket not completely covering the material not covered by the fabric on the master cylinder (ie inactive for the shrinkage) areas of the blanket after lifting from the master cylinder are cooled more than that in the sense of Fixierfolgs in the area covered by the fabric or active areas of the blanket is allowed. For the initially mentioned blanket Krumpfantage the solution in that the peripheral areas of the blanket, which are not touched by the material on the main cylinder, are assigned an additional cooling device that can be adapted to the width of the border areas. Some improvements and further developments of the invention are given in the subclaims.

According to the invention, the inactive areas of the rubber band, which are not touched on the main cylinder of the fabric, ie in particular the areas on the longitudinal edges of the fabric to cool separately and indeed to cool more than that in the active areas of the blanket, with which Fabric is pressed directly against the master cylinder, would be permissible. "Stronger" cooling in the context of the invention means cooling to temperatures significantly, of the order of 5 to 20 ° Celsius, below the minimum temperature still permissible for the active area, such that the amount of heat supplied to the auxiliary cylinder during the cycle of the blanket (short Cooling unit) is completely removed again. Among other things, the invention is based on the finding that once a rubber blanket has been heated up, it is only necessary to slowly cool it again due to the poor thermal conductivity of rubber.

The invention should also be prevented that the inactive areas - from circulation to circulation - even warm up. An intrusion of the heat applied to the main cylinder (and the cooling unit again dissipated) heat energy into the interior of the blanket should be avoided. The heat exchange between the master cylinder and blanket on the one hand and blanket and cooling unit on the other hand, only a thin -. on the order of 2 mm thick outer layer of the blanket concern. This is also achieved by the relatively strong cooling of the edge regions according to the invention.

In the invention, the poor thermal conductivity of the blanket is taken into account or exploited. The heat applied to the outer surface of such a cloth on the master cylinder penetrates only slowly into the depth of the cloth. The same applies to the effect of a blanket cooling, the cooling effect continues only slowly into the depth of the blanket. After a calculation example It takes about two seconds until a lying about 1 cm below the heated blanket surface layer was cooled from 120 to 40 ° Celsius. Since blankets run at a production rate of the order of 50m / min (0.833m / s), about 1.5m of the blanket would be needed for cooling. However, such a cooling length is not available in a compression-shrinking plant. Without application of the invention, therefore, the heat applied to the main cylinder penetrates deeper in the peripheral areas from circulation to circulation and the remaining temperature of the inactive edge regions increases up to an unfavorable equilibrium value for the life of the rubber.

This problem is addressed by the invention in that the inactive edge regions are cooled from the start (essentially from the first circulation) so intensively that the amount of heat previously applied in the same circulation is dissipated almost completely again. This means that the heat energy has no opportunity to penetrate deeply into the material of the blanket - at least not with an impermissible temperature range - and accordingly only a relatively thin outer layer is alternately heated and cooled. If this heated or cooled down outer layer, for example, 2 mm thick, it can be cooled (in the aforementioned calculation example) in the order of 0.3 seconds from 120 ° to 40 ° Celsius; at the above-mentioned speed of 50 m / min then only about 25 cm are needed for the cooling; Cooling this length but are constructive in conventional blanket Krumpfanlagen readily controllable.

The inventive cooling of the inactive edge regions of the blanket is preferably started immediately after starting the machine. Preferably, the cooling capacity per revolution - in the inactive edge areas - should be closed at least approximately equal to the heating power per circulation.

According to another invention, each of the respective width of the edge regions adaptable (additional) cooling device is assigned to the above-defined edge regions of the blanket. For example, air or water jets be directed from nozzles to the inactive edge areas of the blanket. For generating the jets, pivotable nozzle bars carrying the nozzles in question may be provided. The width of the edge areas to be cooled, which is dependent on the width of the treated fabric, can be controlled by a sensor which senses the respective edge of the fabric. Flat jet spray nozzles can be particularly well adapted to the respective measured width of the (inactive) edge area to be cooled. Flat-jet spray nozzles, the spray area of which is stretched on the treated area almost like a line, can be switched in stages depending on the edge width to be cooled. They also allow - among other things by rotation of the spray area (about an axis substantially perpendicular to the blanket blanket - a continuous adjustment to the width of the edge strips to be cooled when the flat jet and thus its spray area rotated according to the edge width or the beam spacing is varied.

As an alternative to a single pivotable nozzle bar, a plurality of stationary nozzle bars can also be provided to adapt to the width. The individual nozzle bar can be assigned to a specific overall width of the respective edge area and can be controlled separately, for example by a valve. The nozzle bars can be equipped with flat jet nozzles. When using these nozzles, it is possible to align the spray area of the flat jet with a predetermined angle against the running direction of the blanket. The respectively required number of stationary nozzle bars depends on the maximum size to be sprayed (to be cooled) of the respectively inactive area of the blanket, ie the ratio of the minimum width of the blanket to the blanket width.

The aforementioned spray angle, with which the spray area of the flat jet is inclined towards the edge of the blanket, should be adjusted separately for each nozzle bar, that is with a different orientation. In a preferred embodiment, the angle at which the spraying area of the flat jet nozzles is inclined towards the blanket edge, at a first nozzle bar, which is associated with an inactive edge area of the blanket, for example 100 mm wide should be made relatively small. At an intended for blanket middle second nozzle beam whose nozzles are to cover a wider, for example, 200 mm wide edge region, the angle is made larger, namely made so large that the line-shaped straight spray area (obliquely) from one to another longitudinal edge of the edge region extends. Nevertheless, in order to obtain the same spray strength per unit area in the longitudinal direction as in the first nozzle bar, two (identically directed) flat jet nozzles can be provided on the second bar. Accordingly, both the angle of the flat jet (measured against the edge of the cloth) and the number of nozzles can be selected to be increasingly larger on each additional, inner nozzle bar. If necessary, the same spraying distance and the same intensity are achieved for each spraying area.

The maximum edge width to be cooled in this way is predetermined by the length of the flat jet spray area. The length can be adjusted by changing the distance between the nozzle and blanket to the edge width. However, if a particularly narrow fabric is treated on a particularly wide machine (with a correspondingly wide blanket) without damaging the blanket, two or more nozzle bar groups of the aforesaid kind can be provided spaced from the length of a spraying area at the edges of the blanket.

As the coolant, as mentioned, water or air (or generally liquid or gas) can be provided. The advantage of air cooling is the better metering, the advantage of a water cooling is the better efficiency; but the sprayed on the blanket water must be squeezed off before the cloth again runs into the area in which it is to exert the compressive crumple.

The inactive edge areas associated coolant, such as nozzles, may have a separately controlled or own coolant supply system in the manner of a countercurrent principle. Optionally, the same coolant, eg

Fresh water, are first used for final cooling of each treated edge areas. The resulting return water is pumped around and used for precooling the same edge area. In this case, it is also possible to proceed in three or more stages - the return water draining from a cooled region is used in each case for cooling an even warmer edge region preceding in blanket running direction.

Fig. 1

eine Prinzipdarstellung im senkrechten Längsschnitt durch eine Gummiband-Krumpfanlage;

Fig. 2

eine Draufsicht auf den Kühlbereich des Gummituchs mit beweglichen Kühleinrichtungen; und

Fig. 3 und 4

ein Ausführungsbeispiel mit stationären Kühleinrichtungen.

Details of the invention will be explained with reference to the schematic representation of exemplary embodiments. Show it

Fig. 1

a schematic representation in the vertical longitudinal section through a rubber band Krumpfanlage;

Fig. 2

a plan view of the cooling area of the blanket with movable cooling devices; and

3 and 4

an embodiment with stationary cooling devices.

Fig. 1 shows a rubber band Krumpfanlage in longitudinal section (perpendicular to the drawn cylinder axes). The plant consists in principle of a heated master cylinder 1, against the lateral surface 2 an endless, stretched in its longitudinal direction blanket 3 is pressed. This is passed over the so-called pressure roller 4 and steering and deflection rollers 5, 6 in the indicated direction of travel 7. The corresponding direction of rotation 8 of the master cylinder 1 is also indicated by an arrow. The fabric web 9 to be shrunk runs in the indicated transport direction 10 via the pressure roller 4 into the so-called shrink nip 11, where the mechanical shrinkage takes place.

The mechanically induced shrinkage is fixed by the action of the heated master cylinder 1 with simultaneous pressing of the web 9 by means of the blanket 3 on the lateral surface 2. The blanket 3 has a predetermined initial thickness to achieve a significant Krumpfeffekts. If the cloth becomes brittle, it must be sanded off. In order to reduce the speed of embrittlement, the blanket 3 is after the expiration of the lateral surface 2 cooled over its entire width by means of a water shower 12. The cooling may only be driven so far that the blanket 3 is still so warm during the subsequent re-arrival at the Krumpf-Nipp 11 that it can support the fixing process on the lateral surface 2 of the master cylinder sufficiently. The applied with the water shower 12 liquid must be pressed before the arrival of the blanket 3 to the pressure roller 4 again to a defined residual moisture, for example with the aid of a pair of nip rollers 13.

Fig. 2 describes embodiments of additional cooling devices according to the invention as a plan view of the blanket 3 and can be viewed as a view in the direction of arrow II of Fig. 1. Accordingly, 3 stumps of the rollers 5 and 6 and the running in the transport direction 10 (finished shrunk and fixed) fabric 9 can be seen in Fig. 2 behind the blanket.

In FIG. 2, a (water) nozzle bar 16 which is pivotable about a support 14 about an axis 15 is shown in the right half. This has a plurality of nozzles 17 which follow one another according to the drawing in the longitudinal direction of the beam 16 and may have a liquid supply line 18 with symbolically illustrated control valve 19. In addition, the beam has a pivot drive 20, which is for example designed so that it can pivot the beam 16 in a predetermined manner about the axis perpendicular to the plane of the drawing axis 15. The pivoting drive can be controlled by means of a sensor 21, which determines by removing the web edge (ultimately), how wide the individual of the fabric 9 on the blanket 3 uncovered edge regions 22 are respectively. With the help of the measurement results of the sensor 21, the pivot drive 20 can be controlled so that the beam 16 with its nozzles 17 each just cools the two edge regions 22 with water.

In principle, similar to the water cooling bar 16 in the right half of Fig. 2, the air cooling beam 23 operates in the left half of Fig. 2. Also this beam can be mounted on the support 14 with its perpendicular to the drawing plane axis 24 and a (not drawn) pivot drive, which can be controlled by a sensor - similar to the sensor 21. The air cooling beam 23 should have a plurality of, for example, as shown, side by side and in the longitudinal direction of the beam 23 successively arranged blowing or cooling nozzles 25. These cooling nozzles are directed by pivoting the beam 23 so on the blanket 3, that they only as possible cool the respective edge region 22. For this purpose, the cooling beam 23 can be moved in the illustrated pivoting direction 26 back and forth. In order to avoid unwanted cooling of the active on the master cylinder 1 portion 27 of the blanket 3, a doctor blade 28 (as well as on the beam 16) can be attached to the beam 23. The active region 27 of the blanket 3, which is in the embodiment, the middle zone of the blanket, bounded between the two edge regions 22, the blanket area, by means of which the fabric web 9 is pressed directly against the lateral surface 2 of the master cylinder 1.

3 and 4 show the adaptation of the cooling area to the fabric width when using a plurality of stationary nozzle bars, wherein the situation on the left blanket edge is described below. On the right edge of the blanket the spraying takes place mirror-inverted. The same parts as in Figl 1 and 2 are referred to the same.

From a collector 31 of Fig. 3, through which the coolant, e.g. Cooling water or cooling air, flows, go from several individual tubes 32. The number of tubes 32 depends on the ratio of minimum fabric width to the blanket width. Each of these tubes 32 is connected to a nozzle bar 33 a to e. Between the respective tube 32 and the associated nozzle bar 33 is a check valve 34th

According to FIG. 3, different numbers of flat jet nozzles are screwed into the nozzle bars 33a to e which follow each other in the direction 35 towards the center of the fabric. It is assumed that each nozzle bar has four ports for screwing nozzles. In the first beam 33a seen from the edge 36, a fan jet nozzle 37a is screwed in a middle position. In the second nozzle bar 33b seen from the edge 36, two flat jet nozzles 37b are screwed. In the third nozzle bar 33c seen from the edge, three flat jet nozzles 37c are screwed in. In the illustration of Fig. 3, the fourth nozzle bar 33d is also equipped with three flat jet nozzles 37d. The fifth nozzle bar 33e of FIG. 3 has four flat jet nozzles 37e. In principle, however, other numbers of nozzles, but also linearly increasing numbers of nozzles (first bar one nozzle, second bar two nozzles, third bar three nozzles, fourth bar five nozzles, etc.) or other spatial distributions of the nozzles can be provided in the various nozzle bars become.

In operation, the nozzles 33a-e on the blanket 3 produce long narrow spray areas 38a-e of Figures 3 and 4. In the described embodiment, the nozzles of the various beams are aligned differently. 4, the spray angles w1 to w5 between flat fan nozzle 37a to e and spray area 38a to e and edge 36 of the rubber band are the same in each individual bar, but varying from bar to bar. As shown, the nozzle 37a is aligned in the first nozzle bar 33a so that the angle w1 between the rim 36 and the spray area 38a becomes relatively small. In this way, a minimal narrow edge region 22a can be cooled. When the second nozzle bar 33b is activated, the angle w2 between the spray area 38b and the edge 36 of the blanket 3 becomes larger than the angle w1 and the edge area to be cooled becomes correspondingly wider. At the third nozzle bar 33e, the angle w3 becomes even larger, etc. Upon activation of the nozzle bars 33e (and their nozzles 37e), an edge area 22b having a maximum width can be cooled. Due to the different number of Flachsttahldüsen 37 on each of the nozzle bar 33 and the different angle w is achieved that the intensity of the spray remains at a larger, bessprühendem, inaktivem edge region-22 of the blanket 3 approximately the same.

The aforementioned angles w1 to w5 can be selected, for example, such that with the flat jet nozzle 37a an inactive rubber strip of 100 mm on each Side sprayed and can be cooled. If the edge area is wider, for example 200 mm wide, the second nozzle bar 33b is switched on and the first nozzle bar 33a is switched off. For even wider edge areas, the next nozzle bars 33c to e are selectively activated. In the context of the invention, however, individual nozzle bars 33 can also be used at the same time for cooling the respective inactive edge area.

LIST OF REFERENCE NUMBERS

1

= Master cylinder

2

= Lateral surface

3

= Blanket

4

= Pressure roller

5

= Steering roller

6

= Guide roller

7

= Running direction

8th

= Direction of rotation

9

= Fabric

10

= Transport direction

11

= Krump-Nipp

12

= Water shower

13

= Squeeze roller pair

14

= Carrier

15

= Axis

16

= Nozzle bar

17

= Water nozzles

18

= Water pipe

19

= Valve

20

= Rotary actuator

21

= Sensor

22

= Border area

23

= Nozzle bar

24

= Axis

25

= Nozzles

26

= Swing direction

27

= active area

28

= Squeegee

31

= Collector

32

= Single tube

33

= Nozzle bar

34

= Shut-off valve

35

= Direction to the cloth center

36

= Blanket edge

37

= Flat jet nozzle

38

= Spray area

w1-w5 =

spray angle

Claims (15)

1. A method for the compressive shrinking of a textile material web (9) by means of a rubber blanket shrinking system, in which the mechanically compressed material web (9) is fixed between an endless rubber blanket (3) and the casing surface (2) of a heated main cylinder (1) and in which the area of the rubber blanket (3) running off the main cylinder (1) is cooled, characterised in that when used on a material web (9) that does not completely cover the rubber blanket (3) the inactive areas (22) of the rubber blanket (3), not previously covered by the material web (9) on the main cylinder (1), are cooled separately and more intensively after removal from the main cylinder (1) than is permissible in terms of successful fixing in the active areas (27) of the rubber blanket (3) covered by the material web (9).
2. The method according to claim 1, characterised in that the inactive areas (22) are cooled by in the order of 5 to 20° Celsius more than the active area (27) of the rubber blanket (3) that is covered by the material web (9) on the main cylinder (1).
3. The method according to claim 1 or 2, characterised in that the amount of heat supplied to the inactive areas (22) during a pass of the rubber blanket on the main cylinder (3) is completely removed by the separate cooling of these areas in the same pass.
4. The method according to at least one of claims 1 to 3, characterised in that the separate cooling of the inactive edge areas (22) takes place from the first pass onwards.
5. The method according to at least one of claims 1 to 4, characterised in that the inactive areas (22) are cooled in stages, preferably according to a type of counter-flow principle.
6. A rubber blanket shrinking system, in which a mechanically compressed material web (9) is to be fixed between an endless rubber blanket (3) and the casing surface (2) of a heated main cylinder (1), and in which cooling means (12) are allocated to the area of the rubber blanket (3) running off the main cylinder (1), in particular for performing the method according to at least one of claims 1 to 5, characterised in that an additional cooling device (16, 23) adjustable to the width of the edge areas (22) is allocated to the inactive edge areas (22) of the rubber blanket (3) not contacted on the main cylinder (1) by the material web (7) - in the area after running off the main cylinder (1).
7. The rubber blanket shrinking system according to claim 6, characterised in that the additional cooling device (16, 23) comprises means for spraying cooling water jets or air jets onto the edge areas (22).
8. The rubber blanket shrinking system according to claim 6 or 7, characterised in that pivotable cooling bars (16, 23) are provided as the additional cooling device.
9. The rubber blanket shrinking system according to at least one of claims 6 to 8, characterised in that at least one sensor (21) allocated to the material web edge is provided for controlling the width of the rubber blanket area cooled by the respective additional cooling device (16, 23).
10. The rubber blanket shrinking system according to at least one of claims 6 to 9, characterised in that for applying the cooling means flat-jet spray nozzles (37a to e) are provided, in particular with a jet that is pivotable about the longitudinal jet axis.
11. The rubber blanket shrinking system according to at least one of claims 6 to 10, characterised in that as an additional cooling device stationary nozzle bars are provided, wherein each edge area (22) is allocated at least one nozzle bar (33a to e).
12. The rubber blanket shrinking system according to claim 11, characterised in that the nozzle bars (33a to e) are arranged parallel to one another and are arranged consecutively in the direction (35) of the centre of the rubber blanket.
13. The rubber shrinking system according to claim 11 or 12, characterised in that the nozzle bars (33a to e) each have a different number of flat-jet nozzles (37a to e) with different spray angles (w1 to w5).
14. The rubber blanket shrinking system according to at least one of claims 11 to 13, characterised in that the nozzle bars (33a to e) each have an increasing number of flat-jet nozzles (37a to e) from the edge (36) in the direction (35) of the centre of the rubber blanket (3), and in that the spraying areas (38a to e) of the nozzle bars produced by the nozzles are oriented to be flatter from the blanket edge towards the centre.
15. The rubber blanket shrinking system according to at least one of claims 11 to 14, characterised in that each nozzle bar (33a to e) is connected to a collector (31) via a shut-off valve (34), and in that the nozzle bars can be controlled with the same nozzle equipment - in pairs on the right and the left.

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