FIBRE TREATMENT DEVICE

Abstract: There is disclosed a fibre treatment device (10) for carrying out treatment of a fibrous material feedstock, and which comprises a treatment roller e.g. an opening roller (11) of a fibre opener device, feeding means (14, 15) for feeding the raw material feedstock to the treatment roller, take-off means (16) for removing the raw material from the treatment roller after treatment, and means for separating trash from the raw material while it is being carried by the treatment roller and for assisting in the orientation of the fibres on the treatment roller; in which a cleaning device (20) is arranged adjacent to the outer periphery of the treatment roller and along an arc between the feeding means and the take-off means, said cleaning device comprising a mounting plate (21) and an array of pins (22) carried by the mounting plate and projecting generally radially relative to the axis of rotation (13) of the treatment roller, and said pins being arranged with their tips at predetermined radial spacings relative to the outer periphery of the treatment roller to provide required co-operation therewith.

Description: FIBRE TREATMENT DEVICE This invention relates to a fibre treatment device for carrying out treatment of a fibrous material feedstock, and which comprises a treatment roller, feeding means for feeding the raw material feedstock to the roller, take-off means for removing material from the roller after treatment, and cleaning means for separating trash from the raw material feedstock while the latter is being carried by the roller and for assisting in the orientation of the fibres on the roller. The invention has been developed primarily (though not exclusively) in connection with a fibre opener device for carrying out pre-treatment of a fibrous material feedstock, in which the treatment roller comprises an opener roller and which is operative in combination with said cleaning means which assists in the separation of trash from the feedstock, and in the initial orientation of the fibres on the opening roller. The pre-treatment of the fibrous feedstock gives a suitable initial preparation of the feedstock prior to feeding of the pre-treated feedstock to a downstream carding machine. Thus, fibre opener devices are used to carry out initial treatment of fibrous raw material feedstock, such as cotton, by separating trash e.g. husks, seeds etc from the raw material, and also to carry out initial orientation of the fibres, prior to delivery of the pre-treated material to one or more downstream carding machines in which further cleaning and orientation of the pre-treated material takes place. The ■ opening rollers of such devices are usually of the pinned, needle or saw tooth type. For convenience, the tips of the pins, needle or teeth of an opening roller will be referred to hereinafter as "fibre-carrying tips" of an opening roller. The initial orientation and "opening" of the fibres is usually carried out by the co-operation between the fibre- carrying tips and: 1 ) the feeding means; 2) usual trash removal device(s) arranged adjacent to the roller periphery; and 3) the take-off means. In known fibre opener devices, the fibrous feedstock is fed to the opening roller by a co-operating pair of feed rollers, and as the fibres are conveyed at relatively high circumferential speed by the fibre carrying tips of the opening roller, trash particles tend to be forced radially outwardly under centrifugal effect from the tips so as to provide initial cleaning of the feedstock. One or more trash removal devices are arranged adjacent to the periphery of the opener roller so as to receive the trash particles, and these devices usually include a trash knife and one or more suction and / or gravity separation chambers arranged adjacent to the opener roller periphery along an arc between the feed rollers and the take-off means. The trash knife is usually arranged immediately downstream of the feed rollers, and is effective to remove trash from the feedstock by a mechanical and also by an aerodynamic effect. In a known arrangement, the trash knife forms a leading end of a cleaning device formed by a fixed carding element having carding wires which co-operate with the fibre-carrying tips of the opener roller to assist in the opening, cleaning, and orientation of the fibres. The co-operation which takes place between the opener roller and the cleaning device operates satisfactorily as far as cleaning, fibre opening and orientation is concerned, and is considered to be acceptable to the industry through many years of use. However, this perceived satisfaction is partly due to the textile industry being relatively conservative in its attitudes, and the long standing use and acceptance of opening rollers (of the pinned type or with "carding-type" wires), and the co-operating cleaning devices with carding type wires. However, as will be well-known to those of ordinary skill in the art, carding-type wires of cleaner devices tend to become clogged with trash particles which become trapped in the gaps between adjacent wires (which inevitably arises during operation over a period of time), and it is necessary to carry out periodic servicing of the wires since the presence of such material has an adverse effect on the cleaning efficiency and the co-operation between the fibre-carrying tips of the opener roller and the wires of the cleaning device. The trash particles tend to "clog" the wires of the cleaning device quite quickly (due to narrow gaps between wires), and it is a difficult task to clean these wires. This is because of the way in which the cleaning device is mounted, in that it is not practical to carry out cleaning of the wires in situ, and it is therefore necessary to de-mount the device for cleaning purposes, and then to re-mount it in position after cleaning has been completed. Also, with existing carding wire type of teeth in the cleaning device, the tips of the teeth are usually arranged in parallel rows, and therefore when the tips of the teeth of the cleaning device co-operate with the roller, there tend to be circumferential striped regions of the fibrous feed stock on the roller periphery which are not subjected to a full cleaning co-operation with the tips of the carding type wire on the cleaning device. The invention therefore, in one aspect, seeks to provide a fibre opener device having an opener roller, and a cleaning device having improved co-operation therewith, in the sense that it is able to perform satisfactorily cleaning and orientation of the fibrous feedstock while being less susceptible to impaired performance and reduction in cleaning efficiency by reason of removed particles from the feedstock becoming lodged or trapped within the components of the cleaning device. According to a first aspect of the invention there is provided a fibre opener device for carrying out pre-treatment of a fibrous raw material feedstock, and which comprises an opening roller, feeding means for feeding the raw material feedstock to the opening roller, take-off means for removing the raw material from the opening roller after treatment, and means for separating trash from the raw material while it is being carried by the opening roller and for carrying out initial orientation of the fibres on the roller, in which a cleaning device is arranged adjacent to the outer periphery of the opening roller and along an arc between the feeding means and the take-off means, said cleaning device comprising a mounting plate and an array of pins carried by the mounting plate and projecting generally radially relative to the axis of rotation of the opening roller, and said pins being arranged with their tips at pre-determined radial spacings relative to the outer periphery of the opening roller to provide required co-operation therewith. However, it should be understood that the invention may be applied to other types of treatment device for treating a fibrous material feedstock, such as a taker-in of a carding machine, in which case the taker-in forms the treatment roller, and to which a fibrous material feedstock is fed after undergoing a pre-treatment by a fibre opener device. Further, the invention may be applied to other treatment rollers in a carding machine, such as the main carding cylinder of a carding machine. Accordingly, in a second aspect of the invention, there is provided a fibre treatment device for carrying out treatment of a fibrous material feedstock, and which comprises a treatment roller, feeding means for feeding the raw material feedstock to the treatment roller, take-off means for removing the raw material from the treatment roller after treatment, and means for separating trash from the raw material while it is being carried by the treatment roller and for assisting in the orientation of the fibres on the treatment roller; in which a cleaning device is arranged adjacent to the outer periphery of the treatment roller and along an arc between the feeding means and the take-off means, said cleaning device comprising a mounting plate and an array of pins carried by the mounting plate and projecting generally radially relative to the axis of rotation of the treatment roller, and said pins being arranged with their tips at predetermined radial spacings relative to the outer periphery of the treatment roller to provide required co-operation therewith. In one preferred development of the second aspect of the invention, the treatment roller is formed by a taker-in of a carding machine. However, it should be understood that the invention may be applied to other types of treatment rollers for carrying out treatment, or pre-treatment of fibrous raw material feedstock, and including, in a further preferred development, the case in which the treatment roller is formed by a main carding cylinder of a carding machine. Further preferred developments of the first and second aspects of the invention will be described below. Preferably, the pins have sharpened tips, to provide a required co-operation with fibre-carrying tips of the roller, and conveniently the pins are mounted on or in an arcuate mounting surface which generally corresponds in curvature to the periphery of the roller. The mounting surface may have pre-formed pin-receiving apertures into which the pins can be entered to a required depth, to provide the required radial- spacing of the pin tips from the roller periphery. Any required setting of the pins, may be achieved by use of a curved template, which is applied to the array of pins after initial insertion, so as to set required radial spacing. The pins extend generally radially with respect to the roller axis, but may be arranged to deviate from a strictly radial arrangement with an angular range which preferably lies between plus 20° to minus 10° with respect to the direction of rotation of the opener roller. A curved mounting plate may be provided to carry the pins, and which extend substantially throughout the length of the roller, and the array of pins may be formed by inserting the pins singly, or as a batch, into mounting holes formed in the plate to a pre-determined depth. The pins may have V-shaped tips, and in a preferred arrangement, the leading flank of each V-shaped tip lies in a generally radial plane with respect to the roller axis, and which provides a particularly advantageous co-operation with the teeth of the roller. By providing an array of pins which are mounted in respective mounting holes in the mounting plate, any required distribution of the pins can be provided e.g. at any required pin density, and relative separation between individual pins in a direction circumferentially, and axially with respect to the roller . Furthermore, it is not necessary for the tips of the pins to be arranged in parallel rows, and indeed rather than arranging the pins in circumferential rows, with each row being axially spaced from the other with respect to the axis of the roller, at least some of the pins in each circumferential row may be axially staggered, and thereby the area of the roller which is swept by the teeth of the cleaning device can be increased so as to minimise the area of the fibrous feedstock which may not be exposed to the action of co-operation between the pins of the cleaning device and the fibre-carrying tips of the roller. Preferably, the cleaning device, as defined above, has an associated trash knife coupled therewith, at a leading end thereof with respect to the direction of rotation of the roller, and the setting of the trash knife can be arranged to provide a required radial separation of its tip from the roller periphery, to provide a required cleaning action in mechanically separating trash particles, and also in having a desired aerodynamic effect on the fibrous feedstock carried by the opening roller. To further assist the removal of trash particles from the feedstock, while it is being carried circumferentially by the opening roller, one or more further types of trash separation device may be arranged along the arc between the feeding means and the take-off means, and may comprise gravity and / or suction discharge chambers. Preferred embodiments of the invention will now be described in detail, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a front view of a first type of fibre treatment device to which the invention may be applied, and which comprises a fibre opener device which is capable of carrying out pre-treatment of a fibrous material feedstock, prior to supply of the pre-treated feedstock to a downstream carding machine; Figure 2 is a detail view, to an enlarged scale, illustrating an improved cleaning device intended to be arranged adjacent to the outer periphery of an opening roller of the general type of fibre opener device shown in Figure 1 , to provide a first preferred embodiment of the invention; Figure 3 is a view in the direction of the arrow A in Figure 2, showing the distribution of cleaning pins of the cleaning device shown in Figure 2; Figure 4 is a front view of a second embodiment of fibre treatment device according to the invention, and taking the form of a taker-in and related components of a carding machine; and, Figure 5 is a diagrammatic front view of a main carding cylinder of a carding machine, and having an improved cleaning device arranged adjacent to its outer periphery, to provide a third preferred embodiment of the invention. Referring first to Figure 1 of the drawings, there is shown a general type of fibre opener device to which the invention may be applied, by way of example only, and which is intended to carry out a pre-treatment of a fibrous raw material feedstock, and then to deliver the treated feedstock to further machines for carrying out subsequent treatment on the feedstock e.g. to a number of carding machines which can carry out further cleaning of the feedstock and further orientation of the fibres. The fibre opener device shown in Figure 1 is designated generally by reference 10 and comprises an opening roller 11 which is rotatable in the direction of the arrow 12 about a horizontal axis of rotation 13. Feeding means in the form of a pair of feed rollers 14 and 15 feed the fibrous raw material feedstock to the roller 11, and take-off means 16 (not shown in detail) remove the treated feedstock from the roller 11. Means is provided to separate trash from the raw material feedstock while it is being carried by the roller 11 , and to carry out initial orientation of the fibres on the roller. The opening roller 11 has fibre-carrying tips of any suitable type and may be of the toothed, pinned or needle type. The device 10 shown in Figure 1 is particularly designed for use in the treatment of cotton, although it should be understood that the invention is applicable to a fibre opener device for the pre-treatment of other types of fibrous raw material feedstock. After receiving the feedstock from the input rollers 14 and 15, the roller 11 conveys the feedstock circumferentially, with the fibre components of the feedstock being borne by the tips of the clothing (e.g. teeth or pins) provided on the roller 11. The circumferential speed of the feedstock is such that trash particles tend to separate and move radially outwardly under centrifugal action, in addition to the action of one or more cleaning device arranged along the arc between the feed rollers 14, 15 and the take-off means 16. In the arrangement shown in Figure 1 , this comprises, successively along the arc, a fixed cleaning device 17 with an adjustable mote knife 18 at its leading end, and a succession of gravity and / or suction chambers 19. In an existing type of cleaning device there are "carding" type wires, the tips of which co-operate with the fibre-carrying tips of the opening roller, to carry out a cleaning action, and also to assist in initial orientation of the fibres which are borne by the opening roller. This co¬ operation has been found to operate generally satisfactorily, as far as cleaning, fibre opening and orientation is concerned, and has been considered to be acceptable to the industry for many years. However, there is a tendency for trash particles to become trapped in the gaps between rows of carding-type wires of the cleaning device, and this arises inevitably during operation over a period of time, and the presence of such material firmly lodged in the gaps impairs the cleaning efficiency, and also may have an adverse effect on the orientation of the fibres borne by the fibre-carrying tips of the roller. Therefore, with the current designs of cleaning device having carding-type wires, it is necessary to carry out periodic servicing of the wires in order to remove trash and other material which has become securely lodged in the gaps between adjacent wires. This is a time consuming task, involving substantial "down-time" of the machine, while the device is removed, cleaned and then re-installed. In a first preferred embodiment of the invention, it is the intention to provide an improvement to the fibre opener device of the general type shown in Figure 1 , by providing an improved cleaning device to co-operate therewith, which is less susceptible to impaired performance and reduction in efficiency which otherwise can be caused by the trash particles which are removed from the feedstock and which tend to become lodged or trapped between the teeth of the cleaning device in known designs. Referring now to Figures 2 and 3, this shows to an enlarged scale an improved cleaning device which is designated generally by reference 20, and which is intended to replace the cleaning device 17 shown in Figure 1. The cleaning device 20 is a type of pinned combing segment which is arranged adjacent to the outer periphery of the opening roller 11 , and comprises a mounting plate 21 carried by a mounting block 21a, and which is of curved shape to correspond generally with the curvature of the outer periphery of the roller 11. The mounting plate 21 carries an array of pins 22 which project generally radially relative to the axis of rotation 13 of the roller 11, and with the pins arranged such that their tips 23 are arranged at pre¬ determined radial spacings relative to the outer periphery of the roller (wires, needles or pins) to provide required co¬ operation therewith. The pins 22 have sharpened tips by grinding or otherwise forming the tips of the teeth to form a V-shape, and as can be seen in Figure 2 it is the leading flank of each V-shape of the tip which extends generally radially towards the axis 13. However, the taper shape given to the pins 22 can be of other forms than that illustrated e.g. so-called Steeple taper, Barrell taper and double taper. The pins 22 can be mounted individually, or in a batch, to fit in pre-formed holes at a required distribution in the surface of the mounting plate 21. The pins can be inserted into the holes, and then a template may be used in order to set the required radial spacing of the tips 23 of the pins. As shown in Figure 2, the pins 22 do not need to extend strictly radially relative to the axis 13, but the general plane of each pin may make a small angle to the radial plane which ranges between plus 20° and minus 10° with respect to the direction of rotation of the roller 11. The most appropriate angle in this range can be determined by experiment, and desirably the angle is such that when the fibres carried by the roller 11 make engagement with the leading edge or flank of each pin, this is a smooth and gentle engagement, rather than a striking action which may tend to wear the leading edge face away quite quickly. As can be seen in Figure 2, the cleaning device 20 includes a holder 24 in which a mote or trash knife can be mounted adjustably, to have its leading edge set at any required radial spacing relative to the periphery of the roller 11. In addition to assisting in skimming off lightweight particles of trash from the feedstock, the knife also induces a venturi effect, so that air drawn into the region immediately upstream of the knife i.e. in the circumferential gap 25 shown in Figure 1 is induced towards the roller periphery and between the roller and the narrow gap with the edge of the knife, thereby drawing back some good fibres that might otherwise tend to be separated unintentionally with the trash particles. It is believed therefore that the first illustrated embodiment of the invention (employing a pinned comb type of cleaning device) will achieve improved efficiency of removal of trash and other undesired material from an opening roller, while ensuring that a higher proportion of good i.e. usable fibres remain adhering to the fibre-carrying tips of the opening roller, rather than being separated out with the trash. Finally, referring to Figure 3, this is a view in the direction of the arrow A in Figure 2, and shows the arrangement of mounting holes 26 in the mounting plate 21 , which receive slidably the pins 22, and which are then anchored in position by any suitable means e.g. adhesive means. It will be noted from Figure 3 that the holes 26 are arranged in parallel rows, but that each row is non-perpendicularly inclined to the transverse axis 27, whereby the cleaning area provided by the pins is divided into separate parallel strips 28, extending perpendicular to the axis 27, and in which successive pins in each strip are axially separated form each other. This means that when the pins co-operate with the periphery of the roller 11 , there are no continuous strip like areas where there will be no contact between the pins 22 and the fibre-carrying tips of the roller 11. Preferred embodiments of the invention therefore have the following advantages, among others: 1. it has much improved resistance to potential clogging of the . cleaning device; 2. there is the potential for increased life of the pins, as compared with use of existing wire teeth, and. much less down-time on repair and maintenance; 3. there is improved and more gentle opening of the fibres, and the potential for increased release of trash and other undesired particles; 4. there is improved distribution of the pins with better co-operation with the fibre-carrying tips of the roller. Furthermore, while only a single cleaning device 20 is illustrated, it should be understood that more than one cleaning device 20 may be arranged at desired position(s) around the periphery of the opening roller 11. However, while the first preferred embodiment of the invention applies an improved pinned comb type of cleaning device to operate in co-operation with the fibre carrying tips of an opener roller of a fibre opener device, to carry out a pre-treatment of a fibrous material feedstock (prior to supply of the pre-treated feedstock to a downstream carding machine), it should be understood that the improved cleaning device of the invention may be applied to other types of treatment roller used in the treatment of fibrous material feedstock. Two further preferred embodiments of the invention will now be described in more detail, by way of example, with reference to Figures 4 and 5 of the. accompanying drawings. Referring first to Figure 4 of the drawings, this shows a front view of part of a carding machine, having a taker-in 30, a feed roller 31 and feed plate 32 which supply pre-treated fibrous material feedstock to the outer periphery of the taker- in 30, and a usual screen 33 arranged adjacent to the outer periphery of the taker-in 30, circumferentially spaced downstream from the feed arrangement (31, 32). The taker-in 30 supplies the feedstock to a main carding cylinder in known manner, not shown in detail in Figure 4. A cleaning device designated generally by reference 34 is arranged adjacent to the outer periphery of the taker-in 30, at a circumferential location between the feed arrangement 31 , 32 and the screen 33, and the construction and arrangement of the cleaning device 34 is generally similar to the cleaning device. 20 which has already been described above in detail with reference to the first preferred embodiment, and shown in Figures 2 and 3. The cleaning device 34 comprises a holder 35 which carries a set of pins 36, whose construction and arrangement is generally similar to the pins 22 which have been already described. The holder 35 is adjustably mounted on a fixed part 37 of the frame of the carding machine, so as to be capable of being adjusted along the lengths of adjustment slots 38 and 39. Evidently, adjustment along the slots 38 and 39 will permit radial adjustment between the tips of the pins 36 relative to the outer periphery of the taker-in 30, and by rocking movement, may permit any desired variation in radial spacing, when measured along the length of the arc between the leading pin 36a, and the trailing pin 36b. In some situations, it may be desirable to provide a variable radial clearance, measured along the arc, although if uniform radial clearance is required, this can easily be obtained by suitable adjustment of the holder 35 relative to the fixed part of the frame 37. The cleaning device 34 is therefore shown being used to separate trash from a pre-treated raw material feedstock while the latter is being carried by a treatment roller in the form of a taker-in 30, and also assists in the orientation of the fibres on the taker-in 30. The advantages which are derived from use of a similar type of pinned comb type of cleaner device 34 in a carding machine, are generally similar to the advantages described above in relation to the pinned comb type of cleaner device 20 used with a fibre opener device as shown in Figures 2 and 3. It should also be appreciated that a pinned comb type of cleaner device (to assist in separation of trash from a fibrous material feedstock, and also to assist in the orientation of the fibres) may be applied to other types of treatment roller, a further example of which is shown diagrammatically in Figure 5. In Figure 5, there is shown diagrammatically a main carding cylinder 40, and at a suitable circumferential location on its periphery, there is arranged a further pinned comb type, of cleaner device, designated generally by reference 41. Although not shown, suitable feeding means (taker-in) will be arranged to supply raw material feedstock to the cylinder 40, take-off means will be provided (doffer) to remove the feedstock after treatment, and the cleaning device 41 will be arranged between the feeding means and the take-off means. The construction and arrangement of the cleaning pins 42 will be generally similar to that described above in relation to the pins 36 of Figure 4, and the pins 22 of Figures 2 and 3. Further, as can be seen in Figure 5, the cleaning device 41 is capable of being adjusted via adjustment slots 43 and 44 to provide any required radial spacing between the tips of the pins 42 and the outer periphery of the fibre carrying tips (carding wire teeth) of the cylinder 40.

Claims: CLAIMS 1. A fibre treatment device for carrying out treatment of a fibrous material feedstock and which comprises a treatment roller (11, 30, 40), feeding means (14, 15; 31, 32) for feeding the raw material feedstock to the treatment roller, take-off means (16) for removing the raw material from the roller after treatment, and means (20; 34; 41) for separating trash from the raw material while it is being carried by the treatment roller and for assisting in the orientation of the fibres on the roller; in which a cleaning device (20; 34; 41) is arranged adjacent to the outer periphery of the treatment roller and along an arc between the feeding means and the take-off means, said cleaning device comprising a mounting plate (21) and an array of pins (22) carried by the mounting plate and projecting generally radially relative to the axis of rotation of the treatment roller, and said pins being arranged with their tips at predetermined radial spacings relative to the outer periphery of the treatment roller to provide required co¬ operation therewith. 2. A fibre opener device (10) for carrying out pre¬ treatment of a fibrous raw material feedstock, and which comprises an opening roller (11), feeding means (14, 15) for feeding the raw material feedstock to the opening roller, take¬ off means (16) for removing the raw material from the opening roller after treatment, and means for separating trash from the raw material while it is being carried by the opening roller and for carrying out initial orientation of the fibres on the roller; in which a cleaning device (20) is arranged adjacent to the outer periphery of the opening roller (11 ) and along an arc between the feeding means (14, 15) and the take-off means (16), said cleaning device comprising a mounting plate (21) and an array of pins (22) carried by the mounting plate and projecting generally radially relative to the axis of rotation (13) of the opening roller (11), and said pins being arranged with their with their tips at predetermined radial spacings relative to the outer periphery of the opening roller to provide required co-operation therewith. 3. A device according to Claim 1, in which the treatment roller is formed by a taker-in (30) of a carding machine. 4. A device according to Claim 1, in which the treatment roller is formed by a main carding cylinder (40) of a carding machine. 5. A device according to any one of Claims 1 to 4, in which the pins (22) have sharpened tips, to provide a required co-operation with fibre-carrying tips of the treatment roller. 6. A device according to Claim 5, in which the pins (22) are mounted on or in an arcuate mounting surface which generally corresponds in curvature to the periphery of the roller. 7. A device according to Claim 6, in which the mounting surface has pre-formed pin-receiving apertures (26) in which the pins (22) can be entered to a required depth, to provide the required radial spacing of the pin tips from the roller periphery. 8. A device according to Claim 7, in which the required setting of the pins (22) is obtained by use of a curved template, which is applied to the array of pins after initial insertion, so as to set required radial spacing. 9. A device according to any one of Claims 1 to 8, in which the pins (22) extend generally radially with respect to the axis of the treatment roller, but are arranged to deviate from a strictly radial arrangement within an angular range which lies between plus 20° to minus 10° with respect to the direction of rotation of the treatment roller. 10. A device according to Claim 6, in which a curved mounting plate (21) carries the pins (22), and said mounting plate (21) extends substantially throughout the length of the treatment roller, the array of pins (22) being inserted singly, or as a batch, into mounting holes formed in the plate to a predetermined depth. 11. A device according to any one of the preceding claims, in which the pins (22) have V-shaped tips, with the leading flank of each V-shaped tip lying in a generally radial plane with respect to the roller axis. 12. A device according to any one of the preceding claims, in which the tips of the pins (22) are arranged in circumferential rows (28) with each row being axially spaced from the other row with respect to the axis of the roller, and at least some of the pins in each circumferential row being axially staggered, whereby the area of the roller which is swept by the teeth of the cleaning device is increased so as to minimise the area of the fibrous feedstock not exposed to the action of co-operation between the pins (22) of the cleaning device and the fibre carrying tips of- the roller. 13. A device according to any one of the preceding claims, in which an associated trash knife (24) is coupled with the cleaning device (20) at a leading end thereof with respect to the direction of rotation of the roller, and the setting- of the trash knife being arranged to provide a required radial separation of its tip from the roller periphery, to provide a required cleaning action in mechanically separating trash particles, and also in having a desired aero-dynamic effect on the fibrous feedstock carried by the opening roller. 14. A device according to any one of the preceding claims, including one or more further types of trash separation device (19) arranged along the arc between the feeding means (14, 15) and the take-off means (16), and comprising gravity and / or suction discharge chambers.

Inventors: STANSFIELD GEOFFREY, STANSFIELD, GEOFFREY
Applicants: CROSROL LTD, STANSFIELD GEOFFREY, CROSROL LIMITED, STANSFIELD, GEOFFREY
Application year: 1996
Main classification: D01G9
IPC codes: D01G9