CA1069326A - Fabric treatment apparatus - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A running fabric web is fed in flat tubular or openwidth form by means of an openwork conveyor belt below a battery of spray bars which apply a liquid such as a scouring solvent onto the fabric. The spray bars are provided with arcuate baffles which convert a spray discharge into a continuous sheet of liquid which pours onto the web. Excess liquid is then removed by a suction box disposed under the belt. A pair of tapered curtains trails along the top of the belt on either side thereof to cover the suction box slot beyond the edges of the fabric which forces the suction action through the fabric. The curtains are wound on a reefing roller by which the curtains may be selectively extended or retracted according to the width of the fabric being processed. The fabric is then delivered through a drying chamber where the material is dried and the excess solvent is recovered.

Description

10~9,3'~
This invention reLates generally to apparatus for treating a running fabric web and more particularly is directed towards an apparatus for solvent scouring textile webs on a continuous basis.

Description of the Prior Art In the manufacture of various types of textiles such as woven or knit goods, certain impurities accumulate in the web. For example, small amounts of oil are applied to the fabric as a lubricant, particularly in the early stages of fabric production. These oils as well as other impurities must be removed at a later stage to provide a clean and finished product.
In my co-pending application, Serial No. 196,836, filed April 4, 1974 under the title "Method & Apparatus For Treating Fabric" and assigned to the same assignee as the present application, there is disclosed a method and apparatus particularly useful for solvent scouring flat tubular or open width webs and subsequently drying the web without stretching or otherwise distorting the web. It is an object of the present invention to provide an apparatus for applying a liquid such as a scouring solvent in a continuous liquid sheet form to eliminate streaking on the fabric. A further object of the invention is to provide improvements in suction boxes for removing excess liquid from a running fabric web.

Summary of the Invention This invention features an apparatus for treating a flat running fabric with a liquid such as a scouring solvent or the like, comprising an open-work conveyor belt adapted to receive and carry the fabric along its upper reach, a plural-ity of spray bars disposed above the upper reach of the beltand an arcuate baffle mounted to each spray bar adapted to convert the discharge therefrom into a continuous sheet of liquid for delivery onto the fabric and be]t. ~
~ .
cb/ - 1 -10~

In one particular aspect the present invention pro-vides apparatus for treating a running fabric web, comprising ~a) conveyor means adapted to carry said web in a substantially flat condition along a predetermined path, (b) a plurality of liquid dispensing stations spaced along said path and adapted to deliver liquid onto said web, ~c) suction means between said stations for removing a portion of said liquid from said web, (d) each of said stations including a tube mounted above and parallel to said conveyor and formed with a plurality of spaced orifices therein oriented in a direction generally parallel to the path of said conveyor and an arcuate baffle mounted parallel to said tube oppositely said orifices with .-the lower free edge of said baffle terminating in spaced relation to the surface of said conveyor and web whereby liquid pumped through said tube will pass O~1t through said orifices to strike said baffle and merge into a continuous sheet of liquid before running off said baffle onto said conveyor.

Brief Description of the Drawings Fig. 1 is a somewhat schematic sectional view in side elevation of a fabric treatment apparatus made according to the invention, Fig. 2 is a detailed sectional side view showing a spray bar made according to the invention, Fig. 3 is a detailed front elevation of the spray bar, Fig. 4 is a detailed top plan view of the suction box closure mechanism made according to the invention, and, Fig. 5 is a detailed sectional view in side eleva-tion of the slot closure mechanism.

Detailed Description of the Preferred ~mbodiment _ _ Referring now to the drawings, the reference char-acter 10 generally indicates a fabric treatment apparatus cb/ - 2 -comprised of modular housin~3 sections 12 and 14 detachably connected to one another along a vertical joint 16. In general, the forward section 12 serves as a solvent scouring chamber while the after section 14 serves as a drying chamber. While the apparatus is primarily intended to scour fabrics, obviously it may be used for various other applications involving the application of liquids to a running web of fabric. The appar-atus 10 is mostly enclosed within the housing formed by side walls 18 and 20, end walls 20 and 22, bottom walls 24 and 26 and top walls 28 and 30.
A running web 32, which may be in flat open width form as for woven fabrics or flat tubular form as for knit fabrics, is carried up an inclined conveyor 34 and dropped onto a downwardly inclined chute 36 extending into the first stage 12 and terminating slightly above the upper reach of a horizontally extending conveyor 38. A feeler 40 is located between the discharge of the chute 36 and the start of the conveyor 38 to control the tension on the web 32 as it is delivered onto the conveyor. The feeler is operatively connect-ed to one of the driving rolls for the feed conveyor 34 andserves to control the rate of delivery of the web into the scouring chamber. If the feed is too fast, the web will drape loosely as it comes off the chute~ whereas, if the feed is too slow, the web will become tensioned. In any event, the feeler will sense the condition and through the control unit, takecorrective action to prevent tension or slack developing in the web.
Mounted above the upper reach of the conveyor 38 are several groups of spray bars 42, 44 and 46 arranged in spaced parallel relation transversely across the conveyor and positioned to deliver successive continuous shects 48 of solvent over the web 3~ as it is carried underneath. Typically, each cb/ - 3 -~O~i~;3'~t;

set of spray bars may be thre~ in number, each ~ar comprised of a tube 50 connected to a source of pressurized liquid, such as a scouring solvent, and formed with a plurality of spaced orifices 32 oriented rearwardly or to the right as viewed in Figs. 1 and 2~
Mounted as by wel~ing or the like to the top of each tube 50 and extending rearwardly and downwardly therefrom is an arcuate baffle 54 having a radius greater than that of the tube 50 and an arc of perhaps 180 whereby the lower edge of the baffle extends forwardly at a point substantially directly below the tube 50 and above the fabric 32. The function of the arcuate baffleis to convert the jet discharges from the several orifices 52 into a continuous sheet 48 of scouring liquid extending the full width of the fabric 32. As shown in Fig. 3, the jets discharged by the orifices 52 stxike against the inner face of the baffle 54 and spread out to merge with adjacent discharges and run down the baffle forming into a continuous sheet extending entirely across the belt without any discontinuities. This has the advantage of eliminat-ing streaking in the fabric and provides a highly effective washing action.
Typically, each set of spray tubes 50 are three in number, each set connected by a conduit 56, 58 and 60, res-- pectively, to its own pump 62, 64 and 66, respectively. Each of the pumps is connected by a conduit 68, 70 and 72 to a drain tank or trough 74, 76 and 78, respectively.
The drain troughs 74, 76 and 78 are mounted adjacent to one another in vertically staggered relation with the tank 74 below the level of the tank 7~ which, in turn, is below ~ the level of the tank 78. The drains from the spray bars above the conveyor collect in the trough with most of the drains running down an inclined wall 80 into the first cb/ - 4 -~o~3z6 trough 78. The wall 80 is located directly below a spray bar 82, similar in construction to the other spray bars, positioned at the end of the sets of spray bars and connected by a conduit 84 to a still from which clean, fresh solvent only will be applied onto the web prior to leaving the scour-ing chamber. Thus, the trough 78, in conjunction with the pump 66, conduits 70 and 7~ and spray bars 46 recirculate relatively clean solvent at this stage since it is closest to the fresh solvent coming from thespray bar 82. The over-flow from the trough 78 goes into the middle trough 76 whichalso receives some drain from its associated spray bars directly : over it and which drains includes those impurities washed down by the set of spray bars 4~. Thus, the second set of spray bars 44 wash the fabric with solvent that is less clean than the solvent going through the spray bars 46, yet cleaner than that in the first set of spray bars 42. The overflow from .. the trough 76 is to the trough 74 which is recycled from the first set of spray bars 42 by means of a pump 54. Since the fabric entering the first part of the scouring station receives -its first cleaning at the first station, the solvent being cir-culated will be relatively dirty in comparison with tne other stages wherein the solvent becomes increasingly cleaner until it passes the spray bar 82 where a completely clean, fresh sol-vent is applied and at which point the fabric is fully scoured.
The re-cycling of the solvent in this fashion provides a very high capacity of washing action which is extremely effective in keeping to a minimum the total quantity of solvent required despite the high pumping volume. The overflow from the trough 74 is to a collection drain 86 which feeds through a line 88 and is pumped back to the still where the solvent is purified and returned to the scouring station through the line 84.

Accessory equipment, such as a storage tank and associated cb/

~0~3Z6 pumps, is provided and connected to the still to compensate the losses due to evaporation, leakage and the like. By re-cycling the solvent in this fashion the cleansing action is multiplied. For example, assuming the pumping capacity from the still is 600 gallons a minute, this washing volume will be multiplied approximately four times by the re-cycling stages, the multiplication factor depending upon the number of re-cycling stages.
The scouring action is further enhanced by vibrating the web as it passes through the scouring station. This may be done by means of an eccentrically rotated roller 90 mounted below the upper reach of the conveyor 38 and adapted to vibrate the belt with the fabric as it moves along. As the fabric is carried by the conveyor 38 out of the scouring chamber, it is carried over a suction box 92 mounted below the upper reach of the conveyor belt and connecte~ by a line 94 to a vacuum pump which discharges the recovered solvent back into the still. In practice, the conveyor belt 38 is in the form of a foraminous screen or mesh material which permits the solvent to pass freely through it.
The suction box 92, as best shown in Figs. 4 and 5, may be of tubular construction formed with a slot opening 96 along its upper portion and over which slot 96 the conveyor belt 33 moves together with the fabric 32. The slot 9~ extends the full width of the conveyor belt 38 in order to accommodate a variety of web widths that may be carried by the conveyor.
Insofar as webs of different widths will be processed by the apparatus, means are provided to close off the ends of the slot not otherwise covered by fabric 32. It will be understood that if a narrow web were to pass over the slot more air would pass through the uncovered ends of the slot than through the fabric and the suc-tion efficiency with respect to the web cb/ - 6 -would be greatly reduced. In order to insure that all of the air passin~ into the suction box is directed through the fabric 32 a pair of flexible curtains 98 and 100 is provided. The curtains at one end are wrapped about a reefing roller 102 mounted above the belt 38 and controlled by means of a hand ~heel 104, or the like, extending from the side of the housing.
As best shown in Fig. 4, the outermost edges of the curtains 98 and 100 extend parallel to the edges of the belt 38, while the inner opposing edges are tapered from the narrowest point at the free end of the curtain converging inwardly so that the portion of the curtains about the re~fing roller 102 are wider. When the belt 38 is operating, and moving in the direction of the arrows, the narrow ends of the curtains will trail from the reefing roller 102 down onto the conveyor belt and carried to the right, as viewed in Figs. 1 and 5, over the top of the suction box to cover the outer ends of the slot opening~96. The length of the curtain being trailed out from the reefing roller 102 is controlled by the hand wheel 104 so that only the parts of the slot not covered by the fabric 32 will be covered by the curtains 98 and 10~. The curtains should be let out so as to intersect the slot at the edges of the fabric 32 as best shown in Fig. 4. In the event a ~ider material is being processed, the reefing roller will be rolled up to bring narrower sections of the curtains into position, whereas if a narrower fabric is being processed, more of the slot must be covered and the reefing roller will be let out to bring wider sections of the curtains into posi-tion. In practice, the curtains are fabricated from a suit-able long wearing material that will not be affected by liquids being used in the process. Various types of materials are available which do not deteriorate in solvents and may be used to advantage.

cb/ - 7 -From the suction box 92 the fabric is carried under another spray bar 106 adapted to deliver a liquid chemical over the width of the fabric. The spray bar is connected by a conduit 108 to an associated pump and storage tanks with excess liquid being recovered by means of a drain board 110;
Various types of chemicals may be applied at this station such, for example, a finishing chemical sold under the trade-mark "Scotchguard" by the 3M Company.
From the finishing station 106 the web is transport-ed into the drying section 14 comprised of a plurality of conveyor belts 112, 114, and 116, arranged one above the other and more fully disclosed in the above-described co-pending ap~lication. The web is carried through the drying chamber along reversely extending paths and is discharged by means of an inclined conveyor 118 up and out of the drying chamber.
There can be provided, in association with the drying chamber, one or more blowers for circulating air and vapour within the drying chamber, heating means for heating the air and vapour and means for condensing at least a portion of the vapour.

cb/

Claims (6)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Apparatus for treating a running fabric web, com-prising:
(a) conveyor means adapted to carry said web in a sub-stantially flat condition along a predetermined path, (b) a plurality of liquid dispensing stations spaced along said path and adapted to deliver liquid onto said web, (c) suction means between said stations for removing a portion of said liquid from said web, (d) each of said stations including a tube mounted above and parallel to said conveyor and formed with a plurality of spaced orifices therein oriented in a direction generally parallel to the path of said conveyor and an arcuate baffle mounted parallel to said tube oppositely said orifices with the lower free edge of said baffle terminating in spaced relation to the surface of said conveyor and web whereby liquid pumped through said tube will pass out through said orifices to strike said baffle and merge into a continuous sheet of liquid before running off said baffle onto said conveyor.

2. Apparatus according to Claim 1 including a drying chamber enclosing said path, blower means connected to said chamber for circulating air and vapor therethrough, heating means communicating with said blower means for heating said air and vapor, and condensing means communicating with said chamber for condensing at least a portion of said vapor.

3. Apparatus according to Claim 2 including vibrating means engaging said conveyor means for vibrating said web.

4. Apparatus according to Claim 2 including chemical application stations along said path for applying chemicals to said web.

5. Apparatus according to Claim 2 wherein said chamber is detachably connected to said stations to provide modular con-structions thereof.

6. Apparatus according to Claim 1 wherein said suction means includes a suction box mounted below said conveyor means and formed with an upper slot extending transversely of said conveyor means, a reefing roller mounted above said conveyor ahead of said slot and a pair of tapered curtains connected to opposite ends of said reefing roller and trailing onto said conveyor means and over the ends of said slot.