Steamer for processing dyed long strip of fabric and method therefor

Abstract: In a steamer (1), a dyed long strip of fabric (3) is spirally guided on guide rollers (7) in a steamy atmosphere to develop and set dye colors, being brought out as a dyed product. Dyes adhering on the guide rollers (7) are washed by washing units (8) so that clean surfaces of the guide roller (7) contact with the dyed fabric strip (3).

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention: This invention relates to a steamer suitable for processing a dyed strip of fabric, and more particularly to a steamer for continuously processing a long narrow strip of fabric which is sectionally dyed in different colors. 2. Description of the Related Art: Heretofore steam processing of dyed fabric is extensively used to develop and set the dyes, since this processing can be performed speedily without interruption. The steam processing is carried out in a sealed steamer. A dyed long strip of fabric is brought into the sealed steamer, guided therethrough for a preset period of time, and then drawn out of the steamer. The dyes are developed and set on the fabric while it runs in the steamer. There are two typical methods for running the dyed fabric. In one of them, a great number of guide rollers are arranged in a staggered manner at the upper and lower parts of the steamer. A dyed long fabric strip is brought into the steamer via an inlet, and is guided around the guide rollers in a zigzag course to be drawn out via an outlet. In the other method, a plurality of guide rollers are spirally arranged in the steamer between its inlet and outlet so that the dyed fabric strip is spirally guided on these guide rollers in the steamer. With these methods, the steamers are very compact and can assure reliable steam processing of the dyed fabric strip in the preset period of time. Recently there are demands for production of a good assortment of long fabric strips in a small amount. To satisfy such demands, it is necessary to dye a fabric strip in one color to a desired length, and then to dye the strip in different colors. Conventionally, a fabric strip dyed in one color and another fabric strip dyed with a different color are connected by a piece of guide cloth having a preset length, being guided into a steamer to be processed continuously. The guide cloth is used to absorb a first dye adhering to the guide rollers and to prevent a second dye from being mixed with the first dye on the fabric strip. With the above method in which the dyed fabric strip is moved in a zigzag course, the fabric strip contacts the guide roller surfaces with an angle of 180° or more. The surfaces of the guide rollers are so extensively stained by the dye of the fabric strip that a great amount of a washing liquid should be used to clean the guide rollers. In this method, both the front and rear surfaces of the dyed fabric strip alternately contact with the upper and lower guide rollers with a relatively strong force. When a dyed fabric strip has fine projections on one surface, such as pile elements of a surface fastener and coupling elements of a fastener chain, these fine projections would be pressed and deformed by the rollers, making the product worthless. The latter method in which the dyed fabric strip is moved in the spiral course can solve the inconveniences of the first method to a degree. However, it is necessary to connect the color changed portions of the dyed fabric strip by pieces of guide cloth, or to discard color-mixed portions to a preset length. When the fabric strip is sectionally dyed in various colors, the guide rollers would be so extensively stained that the steamer should be frequently washed and cleaned by interrupting its operation. US-4 912 946 (corresponding to EP-A-0 312 823), on which the preamble of claims 1 and 5 are based discloses a steamer for processing a dyed strip of fabric. The rollers for the fabric strip are cleaned by cleaning elements which are moved so as to come into contact with the rollers. SUMMARY OF THE INVENTION According to one aspect of the present invention there is provided a steamer for processing a long strip of dyed fabric to develop and set dye colours, the long strip of dyed fabric being sectionally dyed in different colours at predetermined positions, said steamer comprising: - a) a housing having an inlet and an outlet for the dyed fabric strip; b) a plurality of rollers arranged in said housing to guide the dyed fabric strip between said inlet and said outlet; c) a plurality of washing units, at least one washing unit being associated with each said guide roller and each washing unit being adapted to wash a surface of an associated guide roller; d) detection means for detecting the running length of the fabric strip; and e) control means for actuating said washing units on the basis of a signal from the detection means; the steamer being characterised in that the control means is adapted to actuate the washing unit(s) associated with each guide roller in sequence so that a guide roller is washed as, or just before, a portion where the colour of the fabric strip changes passes over the guide roller; and in that the plurality of rollers are arranged to guide the dyed fabric strip in a spiral path. Preferably each washing unit comprises: - a washing nozzle adapted to provide washing liquid; and a squeeze roller adapted to be maintained in contact with an associated guide roller. Preferably the steamer further comprises a plurality of troughs for receiving the used washing liquid and discharging said used washing liquid outwardly of the steamer, one said trough being positioned under each said guide roller. Preferably the steamer is adapted and arranged for processing the long dyed strip after it has been dyed by said dyeing means. According to a second aspect of the present invention there is provided a method of processing a long strip of dyed fabric to develop and set dye colours, the long strip of dyed fabric having a portion where the colour of the fabric strip changes at a predetermined position, said method comprising the steps of:- a) feeding the dyed fabric strip into an inlet of a steamer; b) guiding the dyed fabric strip to an outlet of the steamer using a plurality of guide rollers arranged in a housing of the steamer; c) providing a plurality of washing units, at least one washing unit being associated with each said guide roller and each washing unit being adapted to wash a surface of an associated guide roller; d) detecting the running length of the fabric strip and generating a signal indicative of the length of the fabric strip run; and e) controlling the operation of the washing units on the basis of the said signal; the method being characterised by the step of sequentially actuating the washing units so that each guide roller is washed as, or just before, the portion where the colour of the dyed fabric strip changes passes over the guide roller; and in that the dyed fabric strip is guided in a spiral path by the guide rollers. FIG. 1 is a front view showing arrangement of rollers in a steamer according to an embodiment of this invention; FIG. 2 is a perspective view partially showing the interior of the steamer; FIG. 3 is a side elevational view of the steamer; FIG. 4 is a front view showing a modification of a squeeze roller support; and FIG. 5 is a partial side elevational view of the steamer. An embodiment of this invention will now be described by way of example with reference to the accompanying drawings. A steamer 1 is a sealed vessel having walls 2, being applied steam. To bring in and out a dyed fabric strip, the steamer 1 has an inlet 4 and outlet 5 at a lower front side and rear bottom center, respectively. The inlet 4 is sealed by a sealing member (not shown), and the outlet 5 is sealed by a water seal 5-1. The interior of the steamer 1 is divided into front and rear rooms 1-2, 1-3 by an intermediate wall 1-1 as shown in FIG. 3. A substantially X-shaped brace 6 is erected near the intermediate wall 1-1. A plurality of guide rollers 7 are rotatably supported by roller shafts connected to a front wall 1-4. The guide rollers 7 are arranged along the brace 6 - that is, in substantially X-shaped configuration. The dyed fabric strip 3 is brought into the front room 1-2 via the inlet 4, guided from the outer guide rollers 7 to the inner guide rollers 7 to reach a center of the steamer 1, and then directed outside via the outlet 5. Specifically, the dyed fabric strip 3 spirally runs from the inner peripheral area of the front room 1-2 toward the center of the steamer 1. In this embodiment, all the guide rollers 7 are set in motion by driving means such as a motor (not shown). It is also possible to drive every two guide rollers in combination with the driving means. The guide rollers 7 are supported on the front wall 1-4 by cantilevers in this embodiment to facilitate initial setting of the dyed fabric strip 3 on the guide rollers 7 in the steamer 1. For this purpose, the intermediate wall 1-1 can be opened and closed as desired. It is needless to say that the guide rollers may be supported by opposite ends thereof if some suitable measures are taken to reliably set the dyed fabric strip on the guide rollers. A plurality of washing nozzles 8 are provided, one nozzle 8 to each guide roller 7. The nozzles 8 are mounted below and above the guide rollers 7 which are positioned at the upper and lower portions of the X-shaped brace 6 respectively. The nozzles 8 are arranged to confront their associated guide rollers 7. The washing nozzles 8 may be in any shape. In this embodiment, the nozzles 8 are hook-shaped members extending from the closed end of a pipe. A number of apertures may be formed on the straight portion of the pipe, for example. To wipe the washing liquid off the surface of the guide rollers 7, a plurality of squeeze roller 10 are provided, one squeeze roller to each guide roller. The squeeze rollers are positioned in closed contact with the respective guide rollers 7 near the nozzles 8 and in parallel to the roller shafts. In the embodiment shown in FIGS. 2 and 3, each squeeze roller 10 is as wide as each guide roller 7, and each squeeze roller has flanges at its opposite ends to prevent lateral scattering of the washing liquid. The opposite ends of the squeeze rollers 10 are connected to tension springs 11 whose other ends are connected to the brace 6 or to the front wall 1-4. The squeeze rollers 10 are kept in pressure contact with the guide rollers 7 by the tension springs 11. In other words, the squeeze rollers 10 are suspended by the tension springs 11. FIG. 4 shows a modification of the structure for supporting the squeeze rollers 10. One end of each squeeze roller 10 is coupled to one end of a respective cross arm 12. The cross arms 12 are rotatably supported on the brace 6, so that the squeeze rollers 10 are rotatably supported. A plurality of troughs 13 are provided, one trough 13 being positioned below each guide roller 7 to discherge waching liquid wiped off the respective guide roller outside the steamer 1. As shown in FIGS. 2 and 3, the troughs 13 are laterally and downwardly slanted to conduct the washing liquid wiped by the squeeze rollers 10. A drain channel 14 is positioned near the ends of the troughs 13, discharging the washing liquid outwardly. The brace 6 has a cutaway at its central portion. In the cutaway, a first 15-1 for changing the direction of the dyed fabric strip 3 is erected at an angle of 45° toward the brace 6 at the rising end portion of the spiral running path of the dyed fabric strip 3. A second bar 15-2 with a tilt of 45° is erected in the rear room 1-3. The second bar 15-2 is symmetrical to the first bar 15-1 with respect to the intermediate wall 1-1. The dyed fabric strip 3 passes around the first bar 15-1, through a slit 16 in the intermediate wall 1-1 and around the second bar 15-2 of the rear room 1-3 so that the moving direction of the fabric strip 3 is changed 180°, being guided downwardly to the outlet 5 to be discharged outwardly via the water seal 5-1. This is illustrated in FIG. 5. When the fabric strip is spray-dyed in one color to a preset length before the fabric strip is guided into the steamer and the dye in the nozzle 20 is changed to a new dye by suitable means and sprayed to the fabric strip, the washing liquid is injected to the guide rollers 7 from the washing nozzles 8 at a preset timing in response to change of the dye color. Thereby the rollers adhered with the preceding dye are automatically washed. The timing to perform this is just before the fabric strip dyed in a new color reaches the guide rollers. In the foregoing embodiment, a control unit (not shown) is used. A detector (not shown) detects the running length of the fabric strip 3 based on the number of rotations of the guide roller 7 which is nearest the inlet 4. The control unit determines time lag to operate the washing nozzles 8 according to a signal from the detector to wash the guide rollers 7 in succession. This invention is not limited to timing control of the detector and the washing process. It is necessary to operate the washing nozzles 8 at a proper timing so that the preceding dye of the fabric strip does not mix with the succeeding dye by the guide rollers 7. This invention is applicable not only to the long narrow strip of fabric such as fasteners but also to ordinary strips of fabric. The guide rollers may be washed by washing liquid which overflows from the interior of these rollers in addition to use of the washing nozzles. According to this invention, a plurality of the guide rollers and washing nozzles are arranged so that the dyed long fabric strip is spirally guided on the guide rollers. When a color changed portion of the fabric strip passes over the guide rollers, the guide rollers are automatically washed. The dyed fabric strip contacts the surfaces of the guide rollers with a small angle so that the rollers are barely stained by the dyes, and a little washing liquid is consumed to wash the guide rollers. With the spiral running method, only one side of the dyed fabric is contacted with the guide rollers. Sometimes a fabric strip has fine projections on its one surface such as a surface fastener and a fastener chain having coiled coupling element rows. The fabric strip can be guided on the guide rollers without such surface contacting with the guide rollers, so that such fine projections will not be damaged or deformed, and keeping the product worthy.

Claims: A steamer (1) for processing a long strip of dyed fabric (3) to develop and set dye colours, the long strip of dyed fabric (3) being sectionally dyed in different colours at predetermined positions, said steamer (1) comprising: - a) a housing having an inlet (4) and an outlet (5) for the dyed fabric strip (3); b) a plurality of rollers (7) arranged in said housing to guide the dyed fabric strip (3) between said inlet (4) and said outlet (5); c) a plurality of washing units, at least one washing unit being associated with each said guide roller (7) and each washing unit being adapted to wash a surface of an associated guide roller (7); d) detection means for detecting the running length of the fabric strip; and e) control means for actuating said washing units on the basis of a signal from the detection means; the steamer being characterised in that the control means is adapted to actuate the washing unit(s) associated with each guide roller in sequence so that a guide roller is washed as, or just before, a portion where the colour of the fabric strip changes passes over the guide roller; and in that the plurality of rollers (7) are arranged to guide the dyed fabric strip (3) in a spiral path. A steamer according to claim 1 wherein each said washing unit comprises: - a washing nozzle (8) adapted to provide washing liquid; and a squeeze roller (10) adapted to be maintained in contact with an associated guide roller (7). A steamer according to claim 1 or 2 and further comprising a plurality of troughs (13) for receiving the used washing liquid and discharging said used washing liquid outwardly of the steamer (1), one said trough being positioned under each said guide roller. A steamer according to any preceding claim in combination with a dyeing means, the steamer being adapted and arranged for processing the long dyed strip after it has been dyed by said dyeing means. A method of processing a long strip of dyed fabric (3) to develop and set dye colours, the long strip of dyed fabric (3) having a portion where the colour of the fabric strip changes at a predetermined position, said method comprising the steps of: - a) feeding the dyed fabric strip into an inlet (4) of a steamer (1); b) guiding the dyed fabric strip (3) to an outlet (5) of the steamer using a plurality of guide rollers (7) arranged in a housing of the steamer; c) providing a plurality of washing units, at least one washing unit being associated with each said guide roller (7) and each washing unit being adapted to wash a surface of an associated guide roller (7); d) detecting the running length of the fabric strip and generating a signal indicative of the length of the fabric strip run; and e) controlling the operation of the washing units on the basis of the said signal; the method being characterised by the step of sequentially actuating the washing units so that each guide roller is washed as, or just before, the portion where the colour of the dyed fabric strip changes passes over the guide roller; and in that the dyed fabric strip is guided in a spiral path by the guide rollers.

Inventors: YAMAKITA YOSHIMICHI, YAMAKITA, YOSHIMICHI
Applicants: YKK CORP, YKK CORPORATION
Application year: 1991
Main classification: D06B23
IPC codes: D06B3, D06B1, D06B23, D06B17