Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F26—DRYING
  • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
  • F26B13/00—Machines and apparatus for drying fabrics, fibres, yarns, or other materials in long lengths, with progressive movement
  • F26B13/10—Arrangements for feeding, heating or supporting materials; Controlling movement, tension or position of materials
  • F26B13/12—Controlling movement, tension or position of material
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F26—DRYING
  • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
  • F26B13/00—Machines and apparatus for drying fabrics, fibres, yarns, or other materials in long lengths, with progressive movement
  • F26B13/007—Treating a particular portion of the web or plate, e.g. the edge

Definitions

• the invention relates to a dryer for continuous textile webs according to the preamble of claim 1.
• the invention is based on a device that is described in DE-GM 81 11 908.
• the blowpipes sit at the beginning of the inlet field, possibly also at the end of the outlet field, of a dryer consisting of several fields. They are provided with nozzle slots, the blowing direction of which is aimed at the web edges.
• the upper blow boxes for the large-area loading of the textile webs are missing. This measure apparently serves to create sufficient space for the housing of blowpipes with a relatively large cross-section, and also for the corresponding supply lines with which the blowpipes are connected to the existing air circulation system without an additional fan. Due to the lack of a blow box, only a reduced drying rate can be achieved in the inlet area.
• each additional device comprises an infrared radiator arranged under the web edge and a blowpipe arranged over the web edge.
• each additional device includes a hot air generator in the form of a fan, the suction side of which is connected to the infrared radiator via a suction line and the pressure line of which is connected to the blow pipe.
• the prior art also includes a dryer which has become known from DE-PS 37 06 615.
• this dryer guide plates are attached to the chain rails, through which the drying medium emerging from the blow boxes in the edge zones is to be collected and directed to the edges.
• several guide plates of this type can be lined up on a partial section which is not specified in more detail and which begins at the dryer inlet.
• This dryer has shown that the additional drying power supplied to the edges is relatively weak, so that it is not sufficient in all cases.
• the invention has for its object to provide a dryer according to the preamble of claim 1, in which an effective edge drying is possible without additional space and without reducing the throughput.
• Figure 1 shows in the upper part a side view of a dryer according to the invention and in the lower part the surface temperature of a continuous textile web along the way through the dryer during the drying process.
• Figure 2 shows schematically on a larger scale the first two fields of the dryer with the associated blow boxes and blow pipes.
• Figure 3 shows a cross section through the dryer.
• Figure 4 shows a detail on a greatly enlarged scale.
• FIG. 5 shows part of the detail according to FIG. 4 in a view in the direction of part V of FIG. 4.
• FIG. 6 shows a detail corresponding to FIG. 4 for another exemplary embodiment.
• the dryer shown schematically in FIG. 1 consists of a total of six modular rows 1 to 6.
• Endless tension chains 8, 9 equipped with needle bars 7 are guided in the longitudinal direction through the dryer in the usual manner with rollers 10, 11, 12 on chain rails 13, 14 ( Figure 4 and Figure 6).
• the chain run, on each of which a textile web 15 to be treated is needled, runs on the inside of the chain rail 13, 14.
• the returning run runs on a dryer with a horizontal chain guide, as shown in FIG. 3, on the outside of the chain rail 13, 14 In the case of a vertical chain guide, the returning run lies below the running run.
• the two chain rails 13, 14 are adjustable in the transverse direction so that their distance can be adapted to the width of the textile web 15 clamped in each case.
• the adjustment area comprises an edge zone on both sides, which is symbolized in FIG. 3 by a bracket 16, 17.
• blow boxes 18 are arranged above the textile web 15 in the fields 1-6, two blow boxes 19 each under the textile web 15.
• the lateral edges of the blow boxes 18, 19 largely cover the two edge zones symbolized by the brackets 16, 17. They are provided on the side facing the textile web 15 with nozzle openings indicated by arrows 20 for inflating the drying medium.
• Each blow box 18, 19 is penetrated by a plurality of backflow channels 21 which - compared to the nozzles 20 - have a large cross section and extend from the bottom to the top.
• Each blow box 18, 19 is connected on the pressure side to an axial fan 22, which is accommodated in a fan housing located on a long side of the dryer.
• the axial fans 22 of adjacent fields are arranged on opposite sides in the selected exemplary embodiment, so that they are shown in FIG are only visible for every second field. However, the fans can all sit on the same side.
• a horizontal intermediate floor 23 At a distance below the lower blow boxes 19 there is a horizontal intermediate floor 23. It is provided on the longitudinal side opposite the axial fan 22 with an opening which is covered by a filter 24. Under the filter sits in the space 25 separated by the intermediate floor 23, a heating device, for. B. a burner 26.
• the dryer corresponds to the state of the art.
• blow pipes 27, 28 are fastened to the chain rails 13, 14 and are aligned parallel to the chain rails 13, 14.
• FIG 2 shows, in the length section, which begins at the dryer inlet and extends over the two fields 1, 2 and which therefore comprises one third of the total length of the dryer shown in Figure 1, two blowpipes 27 are strung together, so that the length of a single one Blower tube 27 is approximately as long as the length of a field 1, 2.
• Each blower tube 27, 28 is connected at both ends to branch lines 29, which are each provided with a shut-off device 30. You start from a feed line 31 and are at the joints ⁇ adjacent fields 1, 2; 2, 3 passed between two blow boxes 18.
• the branch line 29 is flexible and stretchable. It consists e.g.
• the feed line 31 is connected to the pressure side of a blower 32 and guided via an additional heating element 33.
• the blower 32 is connected on the suction side by a line 34 to the inlet-side upper blow box 18 of the inlet panel 1.
• blowpipes can also be arranged in the subsequent fields 3 - 6, in particular in fields 3 and 4. These additional blowpipes are on a separate fan, not shown in the drawing, is connected, which is preferably connected on the suction side to another blow box.
• the blow pipe 27 has a square cross section. It is attached to the chain rail 13 with holders 35. It protrudes only slightly above the chain rail 13. On one longitudinal edge, which lies above the needle bar 7, it is provided with a series of round or slot nozzles 38, which are evenly distributed over its length and whose axes are directed towards the edge of the needled textile web 15.
• a wave-shaped bent wire 36 is welded as a needle guard, so that the lower arches protrude downward.
• the exemplary embodiment illustrated in FIG. 6 differs from the previously described exemplary embodiment in that a further blow pipe 37 with nozzles 38 is provided under the needle bar 7, which nozzles aim at the web edge from below.
• the textile web 15 needled on the needle bar 7 with the tension chains 8, 9 is continuously moved through the dryer in the direction indicated by the arrow 39.
• the distance between the chain rails 13, 14 is set according to the width of the textile web taking into account the shrinkage.
• the chain rails 13, 14 with the blow pipes 27, 28 attached to them are located between the upper blow boxes 18 and the lower blow boxes 19.
• the axial fan 22 is used to blow hot drying medium onto the textile web 15 from above and below via the blow boxes 18, 19 blown.
• the drying medium flowing out of it passes through the return flow channels 21 and, if appropriate, through spaces between the blow boxes 18, 19 into the above or below the Blow boxes 18, 19 channels located, as illustrated by arrows 40. From there it flows back to the axial fan 22 via the filter 24 and the space 25.
• drying medium is additionally blown with the blowpipes 27, 28. This is removed from the blow box 18 of the inlet field 1.
• the suctioned drying medium is brought to an increased pressure by the blower 32.
• blowing jets emerging from the nozzle bores 35 are therefore so powerful that the required increased drying performance is achieved at the edges.
• the drying performance at the edges can be increased still further.
• the inlet field 1, at least in its first half, is often operated at an elevated temperature in order to quickly heat up the incoming, wet, cold textile web. Since the treatment medium for the blowpipes 27, 28 is removed from the inlet field 1, the increased temperature in the entire length section, which is equipped with the blowpipes 27, 28 acted upon by the blower 32, benefits the edge drying. In addition, the temperature can be increased by the radiator 33, which is drawn outside the dryer in FIG. 2 for the sake of simplicity, but in practice is preferably accommodated in the dryer.
• the control circuit comprises a device 41 which is arranged at least on one side in the edge region at the outlet of the dryer. Preferably a device 41 is assigned to each of the two web edges.
• the device 41 measures the residual moisture remaining at the edge of the textile web leaving the dryer.
• the device 41 generates a corresponding measurement signal which is fed to a controller 43 via a line 42.
• a reference variable is also input via an input 44, z. B. a signal that corresponds to the setpoint of the residual moisture.
• the controller 43 compares the measurement signal with the reference variable and generates an actuating signal in accordance with the difference determined.
• the actuating signal acts on the drive 45 of the blower 32 in the sense that if the final moisture is too high, the speed increases and thus the intensity of the blowing jets directed onto the web edge is increased. If the final moisture is too low, the speed of the fan 32 is reduced, so that overdrying of the edges is avoided.
• the controller 41 can instead or additionally work in such a way that, depending on the residual moisture measured, the shut-off elements 30 "of the blowpipes 27, 28 are actuated in the various fields of the dryer
• the blowpipes 27, 28 of fields 1 and 2 are switched on, if the final moisture is too high, the blowpipes of field 3 are switched on, and if the final moisture is too low, the blowpipes of field 2 are switched off.
• a further device is arranged at the exit of the dryer in the area of the middle of the web, with which the residual moisture remaining outside the edge areas is measured.
• a corresponding measurement signal is input as a reference variable into the controller 43 via a transmission link which is connected to the input 44.
• the residual moisture of the web edges is continuously automatically adjusted to the residual moisture of the remaining web.
• the dimensioning of the length section which in the exemplary embodiment described comprises the two fields 1, 2, can be understood from the curve in the lower part of FIG. 1.
• the surface temperature of the textile web 15 remains essentially constant after a short heating section up to the end of the field 2. It is always well below 100 ° Celsius in the range of the cooling limit temperature and is almost independent of the temperature of the drying medium in a wide temperature range. The moisture adhering to the surface evaporates in this part of the drying section.
• a marked rise in the temperature is observed, which at the end of the "field 4" approximately reaches the temperature of the drying medium.
• the point F at which the rise begins is the point at which the water adhering to the surface has evaporated.
• the length section in which the blowpipes 27, 28 are arranged thus extends approximately to this point in this case.
• this section the web is insensitive to an excessive temperature of the drying medium. Therefore, according to the invention, this area is used to supply the drying medium to the edges at a high temperature, so that a high evaporation capacity is achieved.
• the subsequent section in which the temperature rises extends far into the field 4. At least in the first part of this section you can still work with an elevated temperature of the drying medium without damaging the material.
• the point F depends on the material properties and the process parameters.
• the section lying in the cooling limit temperature range comprises 20 to at most about 50% of the total length of the dryer. Therefore, the section in which the web edges are exposed to an elevated temperature may not exceed about 50% of the dryer length.
• the shut-off devices 30 enable an optimal adaptation to the individual case. If further blow pipes are provided for the edge drying in the rear area of the dryer, these are supplied with a drying medium, the temperature of which does not exceed the temperature of the drying medium circulated in the end fields.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Treatment Of Fiber Materials (AREA)
• Drying Of Solid Materials (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=7766739

Family Applications (1)

Country Status (6)

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Family Cites Families (16)

• 1995
  • 1995-07-13 DE DE19525545A patent/DE19525545C1/de not_active Expired - Fee Related
• 1996
  • 1996-06-25 US US08/973,633 patent/US5946819A/en not_active Expired - Fee Related
  • 1996-06-25 TR TR97/01371T patent/TR199701371T1/xx unknown
  • 1996-06-25 AT AT96922027T patent/ATE198664T1/de not_active IP Right Cessation
  • 1996-06-25 WO PCT/EP1996/002754 patent/WO1997003331A1/fr active IP Right Grant
  • 1996-06-25 DE DE59606318T patent/DE59606318D1/de not_active Expired - Fee Related
  • 1996-06-25 EP EP96922027A patent/EP0838014B1/fr not_active Expired - Lifetime

Non-Patent Citations (1)

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