Dye fixation apparatus

Abstract

 There is disclosed apparatus for the fixation of dyes or other chemicals to textile fibre comprising a tube, means for packing fibre into the tube at one end thereof, a baffle plate facing the outlet from the tube at the opposite end thereof, means resiliently urging said baffle plate towards said outlet and means for heating the fibre in at least one portion of the tube.

Description

[0001] This invention concerns dye fixation apparatus of the kind comprising a tube into which textile fibre in an unmade form such as loose stock, tops, tows, rovings or slivers for example, is rammed for passage therethrough whilst being subjected to heat treatment.

[0002] One known such apparatus has a tube whose outlet is inwardly tapered to provide a restricted aperture whereby the fibre is packed in the tube to a certain density to control its residence time in the heat treatment zone.

[0003] It is an object of the present invention to provide improved apparatus reducing the mechanical stress to which the fibre is subject and permitting ready adjustment of the density to which the fibre is packed and hence residence time in the heat treatment zone.

[0004] According to the present invention there is provided apparatus for the fixation of dyes or other chemicals to textile fibre comprising a tube, means for packing fibre into the tube at one end thereof, a baffle plate facing the outlet from the tube at the opposite end thereof, means resiliently urging said baffle plate towards said outlet and means for heating the fibre in at least one portion of the tube.

[0005] The tube may be of circular cross-section.

[0006] The means resiliently urging the baffle plate towards the outlet may be comprised by pneumatic or hydraulic cylinders or mechanical springs and the force exerted thereby may be adjustable.

[0007] The tube may be of non-lossy material and the heating means comprised by a radio frequency unit supplying energy to electrodes spaced on opposite sides of said tube.

[0008] There may be a feedhopper into which the textile fibre is delivered, a reciprocating ram adapted on its forward stroke to clear fibre from a base region of said hopper and force it into the entrance to said tube and compaction means adapted to be operated prior to each forward stroke of said ram to compact fibre from within the hopper into said base region thereof for collection by said ram.

[0009] The compaction means may comprise a member of quadrant section pivotally movable from a first position wherein one of its flat faces lies in a substantially vertical plane and forms part of one wall of said hopper to a second position wherein said one flat face lies in a substantially horizontal plane overlying said base region.

[0010] A scraper may be provided to clear the part circular face of said member of quadrant section of fibre collecting thereon whilst in its second position on return to its first position.

[0011] The invention will be further apparent from the following description with reference to the single figure of the accompanying drawing, which shows, by way of example only a diagrammatic sectioned side elevation of one form of dye fixation apparatus embodying the invention.

[0012] Referring now to the drawing, it will be seen that the apparatus comprises a treatment tube 10 of non-lossy material such as polypropylene for example. The tube, which is of circular section may typically have an internal diameter of 30 cm and a length of 500 cm.

[0013] At one end of the tube 10 is a feed hopper 11 adapted to be supplied continuously with textile fibre F from a dye padder generally indicated at 12. A base region 13 of the hopper 11 communicates with an axial inlet 14 to the tube 10.

[0014] A feed ram 15 which can be reciprocated by hydraulic cylinder 16 is adapted on its forward stroke to clear fibre from the base region 13 of the hopper 11 and pack it through inlet 14 into the tube 10. A fork 17 is lowered through gate 18 into tube 10 to keep the fibre packed into the tube 10 in position as the ram 15 is retracted. The fork 17 is of course raised at each forward stroke of the ram 15.

[0015] A compaction device is provided compirising a member 19 of quadrant section having a first flat 20, a second flat face 21 and a part circular face 22. The member 19 is mounted for pivotal movement about an axis 23 (coincident with the junction between faces 20 and 21) between a first position as shown in full lines in the drawing wherein face 21 is substantially vertical to form part of one side wall to the hopper 11 and a second position shown in broken lines wherein face 21 is substantially horizontal within the body of the hopper 11 and overlying the base region 13 thereof. The radial length of face 21 is substantially equal to the width of the hopper 11 in the direction of the axis of tube 10 whereby the face 21 isolates the base region 13 from the remainder of the hopper when member 19 is in its second position.

[0016] The member 19 may be moved between its two positions by an hydraulic cylinder 24.

[0017] The act of moving the member 19 from its first to its second position causes face 21 to gather the bulk of the fibre within hopper 11 and compact it into the base region 13. This is effected immediately prior to each forward stroke of ram 15 whereby such stroke effectively clears the entire content of the hopper 11.

[0018] Whilst member 20 in its second position face 22 forms a temporary base to the hopper 11 enabling fibre feed from dye padder 12 to continue. Member 19 is returned to its first position as the ram is retracted, fibre which has collected on face 22 being scraped therefrom to remain in the hopper 11 by blade 25 under which face 22 moves on its return to the first position of member 19.

[0019] A baffle plate 30 faces and is resiliently urged towards the outlet opening 31 of tube 10 by means of a pair of pneumatic cylinders 32, 33. The ram 15 packs the fibre against the pressure of the plate 30 which may be adjusted by means of valve 40 to supply air to cylinders 32, 33 as process needs require to determine the density of fibre in the tube 10 and hence its residence time therein.

[0020] The fibre will be wet when it enters the tube 10 from the dye padder 12.

[0021] The fibre is heated on passage through a heating zone within the tube defined between spaced radiofrequency electrodes 34 and 35 located on opposed sides of the tube. The heat generates steam and the high humidity and pressure levels ensure good fixation and dye yield.

[0022] A number of small orifices 36 may be provided in the wall of the tube 10 to provide for movement of steam through the packed fibre preventing frosting of the fibre lying against the tube walls as a result of condensation.

[0023] It will be appreciated that it is not intended to limit the invention to the above example only, many variations, such as might readily occur to one skilled in the art, being possible, without departing from the scope thereof as defined by the appended claims.

[0024] Thus, for example, pneumatic cylinders 32, 33 may be replaced by hydraulic cylinders or adjustable mechanical spring means.

[0025] Again, for example, the tube 10 may be of rectangular cross-section and made from other non-lossy material such as PTFE.

Claims

1. Apparatus for the fixation of dyes or other chemicals to textile fibre comprising a tube, means for packing fibre into the tube at one end thereof, a baffle plate facing the outlet from the tube at the opposite end thereof, means resiliently urging said baffle plate towards said outlet and means for heating the fibre in at least one portion of the tube.

2. Apparatus according to claim 1 wherein the force exerted by said resilient means is adjustable.

3. Apparatus according to claim 1 or claim 2 wherein the means resiliently urging the baffle plate towards the outlet is comprised by at least one pneumatic cylinder.

4. Apparatus according to claim 1 or claim 2 wherein the means resiliently urging the baffle plate towards the outlet is comprised by at least one hydraulic cylinder.

5. Apparatus according to claim 1 or claim 2 wherein the means resiliently urging the baffle plate towards the outlet is comprised by at least one mechanical spring.

6. Apparatus according to any one of claims 1 to 5 including a feedhopper into which the textile fibre is delivered, a reciprocating ram adapted on its forward stroke to clear fibre from a base region of said hopper and force it into the entrance to said tube and compaction means adapted to be operated prior to each forward stroke of said ram to compact fibre from within the hopper into said base region thereof for collection by said ram.

7. Apparatus according to claim 6 wherein said compaction means comprises a member of quadrant section pivotally movable from a first position wherein one of its flat faces lies in a substantially vertical plane and forms part of one wall of said hopper to a second position wherein said one flat face lies in a substantially horizontal plane overlying said base region.

8. Apparatus according to claim 7 wherein a scraper may be provided to clear the part circular face of said member of quadrant section of fibre collecting thereon whilst in its second position on return to its first position.

9. Apparatus according to any preceding claim wherein the tube is of non-lossy material and the heating means is comprised by a radio frequency unit supplying energy to electrodes spaced on opposite sides of said tube.

10. Apparatus according to any preceding claim wherein the tube is of circular cross-section.

Drawing