AU668234B2

AU668234B2 - Device for continuously washing dirty greasy wool

Info

Publication number: AU668234B2
Application number: AU52118/93A
Authority: AU
Inventors: Gerold Fleissner
Original assignee: Fleissner GmbH
Current assignee: Truetzschler Nonwovens GmbH
Priority date: 1992-12-19
Filing date: 1993-12-01
Publication date: 1996-04-26
Anticipated expiration: 2013-12-01
Also published as: DE4243166A1; EP0603662B1; EP0603662A1; AU5211893A; DE59302370D1; NZ250503A

Description

IA

The invention relates to a device as defined in the heading of the first Patent claim. A device of this type is known from DE 23 57 055 Al.

Raw wool washing machines of this type have found G extensive use in practice. Their advantage resides in their gentle treatment of the fibrous material, while at the same time affording excellent washing results.

These good treatment results are achieved in that the liquid containing the washing agent flows through the fibrous material immovably held on the cover surfaces of the rotary screens, said fibrous material then, without any action of mechanical washing or conveyor devices, passing through a float run, in the region of which the dirt particles which have been released I during this washing can drop automatically on to the base of the washing machines.

Today the single basic problem in such washing machines remains the perfect and total removal and separation of the immense amounts of dirt which occur during washing.

O The dirt, namely earth, sand and animal fats, released from the wool fibres, accumulates on the perforated base extending through the wash housing. This was particularly the case in the considerably earlier construction according to DE-OS 15 10 182, in which the C; perforated base extends horizontally through the treatment bath. In this case the dirt did not fall entirely through the perforated base into the dirt removal chamber, where cleaning is effected even during operation of the installation. The perforation of the base rather clogged up with individual fibres or coarser accumulations of dirt, so that frequent cleaning of the machine was necessary, interrupting its operation. An improvement in dirt separation was achieved by means of a construction according to DE-OS 20 02 113, in which there is generated above the perforated base a flow of liquid, which was intended, continuously or at intervals, to swirl up the dirt deposited on the base. The flow of liquid used was the one which was necessary in any case in order to .oe..i S 15 recirculate the liquid removed from the rotary screens back into the treatment area, to the outer side of the said screens. For this reason the required distributor duct was located beneath the perforated base, and the outlet openings of this duct placed at points at which the dirt generally accumulated. These measures were also however unsatisfactory. The dirt accumulated :eeei S"laterally of the outlet openings.

A further improvement in this problem resulted from the construction according to DE 23 57 055 Al, from Which the invention proceeds. In this case all previously horizontally-oriented surfaces of the perforated intermediate base were positioned obliquely, in order to cause the dirt to slide automatically in the direction of the dirt removal chambers. As with this orientation to some extent the perforated base was adapted to conform to the curvature of the rotary screens, the dirt now accumul.ated in the convex inwardly-curved areas, i.e. beneath the rotary screens, and in the outwardly curved areas, i.e. between the two rotary screens. In order to prevent accumulation of dirt there in the region of the float run, the liquid return duct was located in the centre between the two rotary screens. In practice it has unfortunately become apparent that the dirt nevertheless deposits on the intermediate base. This applies to the area of the outlet openings, to the float run area and also to the area of the rotary screens.

S"The purpose underlying the invention is, as before, further to develop a device of the type already mentioned, which is self-cleaning. A continuous washing treatment is to be possible, without any need for cleaning procedures which would interrupt the operation of the installation.

I

A solution to this problem was discovered, surprisingly, in the recognition that it is necessary to generate a flow of liquid over the entire length of the bath, parallel to the fleece conveyed through the bath. This additional flow must be present beneath the fleece and above the intermediate base, so that by its means the dirt occurring can be caught and swirled up until it drops through the screen cover into the dirt removal chamber. In the end this is only possible if the wool fibres have been entirely released from the dirt.

In order to embody this realisation in practical form, the invention provides an apparatus for the continuous washing of dirty, grease-containing wool, said apparatus having a bath housing, which accommodates a treatment liquid and is divided longitudinally by a perforated base for separating a treatment chamber from a dirt removal chamber, and having a pair of pressure rollers disposed at an outlet, at least two rotary screens being rotatably mounted in the treatment chamber and being penetrated by liquid from outside inwards as a consequence of a flow of liquid produced by a pump, said screens being partially submerged in the liquid with which the bath housing has been filled, said screens being separated from each other by a float section, the perforated base being substantially adapted to conform to the curvature of the rotary screens and being convexly curved between the S: 20 rotary screens, and a duct to supply a quantity of the liquid discharged from the rotary screens back again to the rotary screens from the outside said duct being disposed of the start of the bath housing extending transversely across the working width wherein the liquid, 25 which is circulated in the bath housing, is exclusively supplied to the treatment chamber via the duct at the start of the bath housing, and wherein an outlet lip of the perforated base, which lip is associated with the pair of pressure rollers, terminates below the liquid level but higher than the lower disposed nip of the pair of pressure rollers. As a result of the invention, the liquid flow generated by introduction of the liquid at the inlet to the respective bath is not disturbed by the cleaning process along the entire bath. This is possible if the liquid circulated in the bath is introduced only at the inlet through the duct, and removed again at the end 4'A4/O 4/1 of the bath. The parallel liquid flow to the fleece is however only possible if a large amount of liquid also flows ,ut at the end of the bath. For this reason the outlet lip at the end of the treatment area has been located lower than the level of the liquid. Then the wool fleece cleaned in the bath flows out along with the outgoing liquid, and is passed to the pair of press rollers by this :o e e flow, without stoppage. For this purpose, the roller nip of the pair of press rollers is also located lower than the outlet lip. This is effected contrary to prior art according to the abovenamed Disclosure Documents, in which the roller nip is always located level with the liquid level within the bath, in order that as little liquid as possible need be squeezed out in the press, and also in order to lose as few wool fibres as possible in front of the pair of press rollers by reason of outflowing liquid. The device according to the invention accepts this disadvantage. It however avoids loss of fibres, because these fibres flowing out of the fleece strip with the squeezed-out liquid are pumped back into the bath, i.e. at its start.

By means of the present advantageous measure of having to provide a liquid return duct extending transversely across the working width only at the bath inlet, the removal of dirt in the dirt removal chamber is no longer disturbed by any of the components of the device. In the bath housing therefore only one dirt removal chamber is necessary, extending over the entire length of the bath housing.

Particular attention is directed towards the outlet: lip, which must not only ensure continuous removal of the arriving wool fleece, but also uniform removal of the accompanying liquid.

An embodiment of the device according to the invention, given by way of example, is illustrated in the drawing, which shows: Fig. 1: a longitudinal section through a cleaning installation for raw wool, comprising a plurality of baths; Fig. 2: a section transversely through the installation according to Fig 1, along line

II-II;

Fig. 3: a section transversely through the installation according to Fig. 1, along line III-III, and Fig. 4: a wash bath in the region of the pair of press rollers, on an enlarged scale.

The raw-wool washing device comprises a plurality of bath housings 1, containing the liquid up to a level 2, and in each of which three rotary screens 3, 4 and .oeo• are mounted. The treatment area 6 in this bath housing 1 is separated from the dirt removal chamber 7 by a perforated base 8. This base is adapted to conform to the curvature of the rotary screens 3-5 and, in order to form the treatment area 8, located at a distance from rotary screens 3-5. Between the respective rotary screens 3-5 is in each case located a float run 9 for the raw wool 10, and in the region of which the perforated base 8 is outwardly curved in a convex manner. The dirt removal chamber 7 is formed by a hopper 11, upon whose walls the dirt removed from the fleece continuously slides to the removal opening 12.

The liquid penetrating through the perforations in the respective rotary screens into the interior thereof flows in accordance with Fig. 2 at the end faces of the rotary screens automatically out through openings 1.

into longitudinal ducts 14, 15 which are externally flanged on to the ends thereof. The liquid flowing into duct 14 passes through a pipeline 16 into the duct from which point all the liquid is pumped with the aid of pump 17 into the duct 18, which extends, at the 15 start of the bath housing i, transversely across the working width; from this duct 18 the liquid flows over an inlet lip 19 into the treatment area 6. This liquid, recirculated, flows from this point on the one hand through the newly-entering fleece 10 and then through the first rotary screen 3, but because of the liquid overflowing inwards, parallel to the fleece 10 in accordance with arrow 20. The same applies in the region of the float run 9. Then a certain amount again flows through rotary screen 4, but the remainder again flows in the direction of arrow 21 in the direction of the outlet, i.e. towards the pair of press rollers 24, 27. Because of this parallel flow 20, 21, the dirt released from and falling from fleece 10 cannot accumulate on the surface of the perforated base. It 8 either falls directly through the perforations in the base 8 into the dirt removal chamber 11, or is again swirled up by the parallel flow 20, 21, any wool fibres still adhering to the dirt being again fed upwards to the fleece, and these are washed until the dirt particles drop out and then immediately drop into the removal chamber 11. In any case, because of the flow 21, deposition of dirt on the base 8 is not possible, and the parallel flow has a self-cleaning action over the entire length of the bath.

The construction of the outlet of each bath may be seen in detail in Fig. 4. Here the outlet lip 22 is located lower down than the liquid level 2 or the axis of rotation of the rotary screen 5. This has the result that a large amount of treatment liquid fl)ws out to the press roller nip 23 together with the squeezed-out wool fleece 10; this, however, is of no disadvantage for the wool. On the contrary, this ensures continuous removal of the wool. The outlet lip 22 of the perforated base 8 is located at a distance from the roller nip 23. The distance between the lower press roller 24 and the outflow lip 22 is bridged over by an addicional perforated base plate 25. The base plate is upwardly curved in a convex manner. This configuration of the base plate 25 ensures rapid removal of the fleece 10 for squeezing. The outlet end 26 of the base plate 25 is associated, not with the squeezing nip 23, but with the lower press roller 24, so that a blockage of wool fibres cannot occur.

In order to facilitate dismantling of the pair of precs rollers 24, 27, or also to improve cleaning of the roller nip 23, the base plate 25 is mounted to pivot to and fro in the bath housing 1 in relation to the outlet lip 22.

A liquid catchment tub 28 is located beneath the outlet lip 22, the base plate 25 and also the pair of press rollers 24, 27; this tub 28 catches and collects in hopper 29 both the squeezed-out liquid and also wool fibres which have run out. With the aid of a pump and of an additional pipe 31, the fibres are passed back into the wool strip The pipe 31 opens at the start of the bath at the point 32 or 33 into the bath housing 1. In this way loss of fibres is entirely avoided.

Claims

2. An apparatus according to claim 1, characterised in that only one dirt removal chamber is disposed on the bath housing extending over the entire length of the bath housing, beneath all rotary screens or float runs provided therein.
3. An apparatus according to claim 1 or 2, characterised in that the rotary screens are disposed close together, in the bath housing and are separated from one another only by a short float run.
4. An apparatus according to claim i, characterised in the roller nip of the pair of press rollers is disposed lower down than the axis of rotation of the rotary screens.
5. An apparatus according to any one of claims 1 to 4, characterised in that the roller nip of the pair of press rollers is disposed at a distance from the outlet lip.
6. An apparatus according to claim 1, 4 or characterised in that an additional base plate extends between the outlet lip and the lower-located roller nip of the pair of press rollers.
7. An apparatus according to claim 6, characterised in that the additional base plate is mounted to pivot to and fro between the pair of press rollers and the outlet lip. 15 8. An apparatus according to claim 6 or 7, characterised in that the outlet end of the additional base plate is associated with an upper quarter of the lower roller of the pair of press rollers which runs upwards during operation.
9. An apparatus according to any one of claims 6-8, characterised in that the additional base plate is *perforated. An apparatus according to any one of claims 6-9, characterised in that the additional base plate is 25 upwardly curved in a convex manner.
11. An apparatus according to any one of claims 1-10, characterised in that there is disposed, at a spacing beneath the outlet lip, beneath the additional base plate and beneath the pair of press rollers, a liquid catchment tub, whose liquid circulation is connected via a pipeline with interposed pump to the start of the bath of the immediately preceding bath housing.
12. An apparatus for the continuous washing of dirty, grease-containing wool substantially as hereinbefore described with reference to the accompanying drawings. DATED this 15th day of February 1996 FLEISSNER GmbH CO MASCHINENFABRIK Patent Attorneys for the Applicant: F.B. RICE CO. o ee as S:: **e Abstract Device for continuously washing dirty, greasy Wool Raw wool contains a large amount of dirt, and in addition animal fat must be cleaned therefrom. during washing the wool must not become felted. Machines are known in which the wool fleece is washed in sections in rotary screens, and then floats free. The dirt then drops out in the float runs. A hopper-shaped removal chamber is provided in order to collect the dirt, beneath a perforated base which defines the treatment area. The dirt frequently accumulates on the base, oeoeo: 15 which is necessary in order to avoid fibre loss, and clogs the perforation holes. In order to avoid stopping io:: the machine for cleaning, steps are taken to establish a parallel flow of the liquid, between the perforated base and the rotary screens and also in the region of the float runs, said parallel flow being established over the entire length of the bath, the liquid gee.oi S•circulated in the bath being introduced only at the inlet to the bath, and a larger amount of liquid flowing out in the direction of transport of the fleece by reason of lowering the outlet edge at the end of the bath, and lowering the level of the press rollers.