This invention relates to a trash cleaning system for a textile machine for treating fibrous feedstock, such as an opening and cleaning machine, or a single or double card.

As is well known, in the processing of a raw material fibrous feedstock, to render it into a form suitable for spinning, substantial quantities of trash e.g. husks, unwanted tufts etc are separated from the raw material, and many different means are employed to separate such trash from the raw material, and then to convey the trash away to suitable collecting and disposal points, while allowing the now cleaned feedstock to pass through various processing stages.

In the operation of carding machines, it is known to provide under card cleaning systems, in which trash or other waste which falls from the underside of the card is directed into plenum chambers and then discharged to a remote collection or disposal point. Negative pressure is generated within each plenum chamber so that an air-borne stream of trash can be drawn from the underside of the card and into the plenum chamber.

It is also known to use air jets aimed at predetermined regions of the card in order to assist in the separation of trash from the fibrous feedstock which is undergoing processing, and one known jet cleaning system is disclosed in US 4433455 which is particularly suitable for use in cleaning beneath carding machines, although it is applicable generally to the cleaning of waste from beneath machinery. However, in this and other known jet cleaning systems, compressed air supply to the jets is only maintained while the machine is operating, and when the machine is stopped (whether for routine cleaning or otherwise) the air driven cleaning system ceases to operate.

In large scale operation of carding machines to process cotton feedstock, it is present practice for the cards to be shut down on a regular basis (either individually or by shut-

down of the entire plant), and then for manual cleaning to be carried out to remove the trash particles which inevitably build-up in parts of the machine despite the use of trash cleaning systems.

In a large scale operation, it is necessary to schedule these shut-downs on a regular basis e.g. once or twice per working shift, and this involves unproductive labour cost in carrying out manual cleaning operations, and regular periods of underutilisation of a capital resource.

The present invention has therefore been developed with a view to reducing the frequency of machine stoppage for routine cleaning purposes, using a novel arrangement of air jet cleaning systems.

The invention is particularly suitable for use with a carding machine (single or double card), though it should be understood that the invention may be applied to other types of textile machine which process a fibrous feedstock e.g. fibre opening and cleaning machines.

According to a first aspect of the invention there is provided a textile machine for treating a fibrous feedstock and comprising a cleaning system for collecting trash particles separated from the feedstock prior to and / or during treatment, in which the cleaning system comprises: a collecting surface arranged to receive trash particles separated from the fibrous feedstock; at least one plenum chamber arranged to cooperate with the collecting surface; a primary jet cleaning system arranged to blow air over the collecting surface and to move trash particles on the surface into the field of influence of the plenum chamber, said primary jet system being arranged to be supplied with a compressed air supply while the machine is operating to process fibrous feedstock; and, a secondary jet cleaning system arranged to direct cleaning air to any areas where trash particles may accumulate, said secondary jet system being arranged to be supplied with compressed air whenever additional cleaning is

required.

Preferably, the cleaning system is used to clean the underside of a textile machine, though it may be employed to clean other areas of the machine e.g. at or above the level of a carding cylinder.

According to a further aspect of the invention there is provided a textile machine for treating a fibrous feedstock and comprising at least one cylinder, and an under cylinder cleaning system for collecting trash particles separated from the feedstock prior to and / or during treatment, in which the cleaning system comprises: a collecting surface arranged below the cylinder to receive trash particles separated from the fibrous feedstock and falling under gravity onto the surface; at least one plenum chamber arranged to cooperate with the collecting surface; a primary jet cleaning system arranged to blow air over the collecting surface and to move trash particles on the surface into the field of influence of the plenum chamber, said primary jet system being arranged to be supplied with a compressed air supply while the machine is operating to process fibrous feedstock; and, a secondary jet cleaning system arranged to direct cleaning air to the underside of the cylinder and / or any other areas of the under cylinder region where trash particles may accumulate, said secondary jet system being arranged to be supplied with compressed air whenever additional cleaning is required.

Therefore, the primary jet cleaning system will usually operate in a continuous sequence e.g. 5 seconds every 20 minutes while the machine is operating to treat a fibrous feedstock (by directing or at least assisting the movement of the trash on the collecting surface to the plenum chamber), whereas the secondary jet cleaning system will usually be operated intermittently to cause any accumulation of trash particles lodged in the under cylinder region (which have failed to be dislodged and to fall under gravity onto the

collecting surface) to be dislodged and to fall under gravity onto the collecting surface for subsequent movement by the first jet cleaning system to the plenum chamber.

The invention therefore provides a management control system for a textile machine which at least reduces the frequency of predetermined downtimes for cleaning purposes, since the secondary jet cleaning system can be set into operation intermittently at any required rate and / or to be operated automatically as a function of other operating parameters of the machine.

By way of example only, in one preferred arrangement the secondary jet cleaning system may be operated each time the normal feedstock treatment operation of the machine is stopped. Therefore, it is not necessary to stop the machine purely for cleaning purposes, but advantage can be taken of any machine stoppage for other reasons to provide additional cleaning of any accumulation of trash.

A compressed air supply is usually available in a production plant, of a capacity sufficient to operate the primary cleaning jet systems of the machines in the plant (and any other air driven equipment), and conveniently a diverter valve arrangement is provided in the or each machine which can operate automatically to switch the compressed air supply from the primary to the secondary jet system whenever normal machine operation is stopped.

The primary jet cleaning system may comprise a travelling air jet nozzle arrangement which reciprocates linearly along one edge of the collecting surface e.g. as disclosed in US 4433455, and which blows air over the collecting surface towards an opposite edge thereof.

A ramp may extend downwardly from the opposite edge to direct trash towards the plenum chamber which draws the trash into the chamber and then discharges the trash to a suitable collecting point for disposal, or for re-treatment if usable fibres have been carried over with or in the trash.

The invention may be applied to the underside of a carding engine, in which case the collecting surface will

extend below the carding cylinder. The carding engine may be a single card or a double card, and in the latter case a separate collecting surface and associated primary and secondary jet cleaning system may be provided for each carding cylinder.

One embodiment of trash cleaning system according to the invention will now be described in detail, by way of example only, with reference to the accompanying drawing, in which:

Figure 1 is an end view of a double card incorporating a trash cleaning system according to the invention; and,

Figure 2 is a view, similar to Figure 1 , showing operating components of the card in more detail.

Referring now to the drawing, it should be understood that a double card is merely one example of a textile machine for treating fibrous feedstock to which the invention may be applied, and that the invention may be applied to other types of textile machine, such as opening and cleaning machines. Also, while the illustrated embodiment is a double card, the invention may equally be applied to a single card.

Referring to the drawing, the textile machine is designated generally by reference 10 and comprises first and second carding cylinders 11 and 12, and associated taker-in Til, T12, doffer DI 1 , DI2 and movable flats F11 , F12 which can be of known construction, and which will not be described in detail herein. The textile machine 10 is therefore capable of treating a fibrous feedstock, and comprises at least one treatment cylinder, which in the case of a carding engine, comprises a wire toothed cylinder. In addition, an under cylinder cleaning system is provided for collecting trash particles separated from the fibrous feedstock prior to and / or during treatment. The under cylinder cleaning system i.e. the system to clean the under region of the machine will now be described in detail.

The collecting system is located in the under cylinder region designated generally by reference 13, and comprises a collecting surface 14 which extends horizontally and

substantially throughout the length of the associated cylinder, and also, as can be seen in figure 1, it extends substantially throughout the horizontal transverse dimension of the cylinder. The collecting surface 14 is arranged to receive trash particles separated from the fibrous feedstock which falls under gravity onto the surface during normal machine operation.

At least one plenum chamber 15 is arranged to cooperate with the collecting surface 14, and a primary jet cleaning system is arranged to blow air over the collecting surface 14 and to move trash particles on the surface 14 into the field of influence of the plenum chamber 15. The primary jet cleaning system is shown schematically only in figure 1 , designated generally by reference 16, and may comprise a first linearly reciprocable travelling jet system as shown in more detail in figure 2, and which may be of the type shown and described in more detail in US 4433455. However, it is not essential for the primary jet cleaning system to be as disclosed in the US patent, or indeed for it to be a travelling jet cleaning system.

The primary jet cleaning system 16 is provided with a compressed air supply, which is usually available in a fibrous feedstock treatment plant, and will usually be operated in a continuous sequence e.g. 5 seconds every 20 minutes while the machine is operating to process the feedstock.

In addition, a secondary jet system is provided (not shown in detail in the drawings) which is arranged to direct cleaning air to the underside of the cylinder 11 or 12 and / or any other areas of the under cylinder region 13 where trash particles may accumulate, and this secondary jet cleaning system is arranged to be supplied with compressed air whenever additional cleaning is required. Possible locations for cleaning air jets of the secondary jet system are shown schematically by references 23 in the drawings.

The primary jet cleaning system 16 operates in a continuous sequence while the machine is operating to treat a

fibrous feedstock, by directing or at least assisting the movement of the trash on the collecting surface 14 to the plenum chamber 15, whereas the secondary jet cleaning system will usually be operated intermittently to cause any accumulations of trash in the under cylinder region 13 (which have failed to be dislodged during normal operation) to become dislodged and to fall under gravity onto the collecting surface 14 for subsequent movement by the primary jet cleaning system 16 to the plenum chamber 15.

The secondary jet cleaning system can be arranged to be set into operation intermittently at any required rate and / or to be operated automatically as a function of any predetermined operating parameters of the machine. In a preferred arrangement, the secondary jet cleaning system is operated each time the normal feedstock treatment operation of the machine is stopped.

The compressed air supply will be directed to the primary jet cleaning system during normal feedstock treatment, but preferably a diverter valve arrangement (not shown) is provided in the machine to operate automatically and switch the compressed air supply from the primary jet cleaning sequence or system 16 to the secondary jet cleaning system whenever normal machine operation is stopped.

As can be seen in the drawings, the collecting surface 14 associated with cylinder 11 has an inclined ramp 17 at one side which serves to guide trash particles downwardly towards the plenum chamber 15, and has a further ramp 18 at its opposite side onto which can fall under gravity trash particles from a transfer zone 22 intermediate the carding cylinders 11, 12 and having a train of transfer cylinders above the ramp 18 and intermediate the cylinders 11 and 12. The primary jet cleaning system 16 has a second fixed nozzle block which blows air to assist the downward movement of these trash particles over ramp 18 and towards a plenum chamber 19 arranged in the region intermediate cylinders 11 and 12.

The cylinder 12 is similarly provided with collecting

surface 14a, ramp 17a and plenum chamber 15a. Also, a further nozzle arrangement 20 blows air over collecting surface 21 above plenum chambers 19, 15a to direct trash falling from the train of cylinders above and intermediate the cylinders 11, 12.

The air blown down ramp 18 and over surface 21 serves particularly advantageously to remove trash generated during slow speed piecening operations.

While the primary and secondary air cleaning systems are shown and described in relation to undercard cleaning, they may also be employed in cleaning of other regions of a textile machine or carding engine.