WO2013114279A1

WO2013114279A1 - Suction nozzle of a carding machine

Info

Publication number: WO2013114279A1
Application number: PCT/IB2013/050760
Authority: WO
Inventors: Mario Mascheretti
Original assignee: Marzoli S.P.A.
Priority date: 2012-01-31
Filing date: 2013-01-29
Publication date: 2013-08-08
Also published as: CH707856B1; DE112013000773B4; DE112013000773T5; BR112014018855B1; CN104204316A; IN2014MN01445A; BR112014018855A2; BR112014018855A8; CN104204316B

Abstract

A suction nozzle unit (20) of a carding machine comprises a suction chamber (22) and means of adjustment (50) with a shutter element (52), adjustable to shut off the inlet aperture (22) of the suction chamber (22). Moreover, a further suction nozzle unit (1020) of a carding machine comprises a suction chamber (1022) and a deviation element (1070) upstream of the inlet aperture (1022a) of the suction chamber, adjustable to adjust the deviation with respect to a drum (101) of the carding machine.

Description

DESCRIPTION

"SUCTION NOZZLE OF A CARDING MACHINE"

The present invention relates to a suction nozzle_, of a carding machine on a yarn spinning line.

On a yarn spinning line, the fibre, for example in tufts, is first taken from bales, subjected to cleaning and opening operations and forwarded for carding.

Carding, as known, is an operation of primary importance, in that the fibre fed in tufts, is further cleaned and parallelised, coming out in web form for subsequent processing .

Suction nozzles and fixed knives, sometimes integrated in a single component, such as for example illustrated in US 6,726,027, which operate on the fibre pulled in rotation by the drum, have the specific function of separating the dirt and impurities from the fibre.

The choice and regulation of such components is of considerable importance, in that there is a risk of operating in an overly aggressive manner, with the risk of also aspirating fibres good for production or of operating in an overly bland manner, with the risk of obtaining a fibre in output from the carding which is too dirty and full of impurities.

The purpose of the present invention is to make a suction nozzle unit for a carding machine which allows an optimal adjustment of the cleaning action and separation of the impurities.

Such purpose is achieved by a suction nozzle unit made according to claim 1 and depending thereof.

The characteristics and advantages of the suction nozzle unit according to the invention will be evident from the description below, made by way of a non-limiting example according to the attached figures, wherein:

- figure 1 shows a drum, an input cylinder and an output cylinder of a carding machine, provided with suction nozzle-knife units according to the present invention, according to one embodiment;

-figure 2 shows the suction nozzle unit in figure 1, in a configuration of minimum deviation;

-figure 3 shows the suction nozzle unit in figure 1, in a configuration of minimum deviation;

figures 4a to 4d show embodiment variations of functional groups comprising at least one suction nozzle unit according to the present invention;

- figures 5a, 5b and 6 show further embodiment variations of the suction nozzle unit ^' according to the present inventio .

According to the invention, a carding machine comprises a drum 1 rotatable around a drum axis, provided on the surface with a covering for pulling the fibre in tufts. Moreover, the carding machine comprises an introduction cylinder 2 or briseur, rotating on command and covered on the surface, counter-rotating in relation to the drum 1, operatively engaged upstream with a feed duct of a feed silo of the fibre in tufts and downstream with the drum 1, to which the fibre is transferred.

In addition, the carding machine comprises an extraction cylinder or doffer 4, downstream of the drum 1. The doffer 4 is covered on the surface, rotating on command and counter-rotating in relation to the drum, and operatively engaged with the surface of the l'atter, to pick up the fibre.

In addition, the carding machine comprises a movable flats device 6 comprising a plurality of flats 8, translating along a closed circuit comprising a processing section parallel to the processing surface of the drum 1.

Compared to the drum 1, the processing section of the movable flats device extends from an initial line 10, defined as the straight line passing through the centre of the drum and the point of the processing, circumference of the drum where the translating flats 8 disengage from the drum, and an end line 12, defined as the straight line passing through the centre of the drum and the point of the processing circumference of the drum where the translating flats 8 begin engagement with the drum. The zone of the lateral surface of the drum between the initial line and the end line is defined the main carding zone .

A straight line passing through the centre of the drum and the centre of the briseur defines a diametrical briseur-drum transfer line 14, in that, at its intersection with the outer processing surface of the drum, an area is formed in which the fibre migrates from the surface of the briseur to the surface of the drum. The zone of the drum 1 contained between the initial line 10 and the briseur-drum transfer line 14 defines a pre- carding zone.

A straight line passing through the centre of the drum and the centre of the doffer defines a diametrical drum- doffer transfer line 16, in that, at its intersection with the outer processing surface of the drum, an area is formed in which the fibre migrates from the surface of the drum to the surface of the doffer.

The zone of the drum 1 contained between the end line 12 of the main carding area and the drum-doffer transfer line 16 defines a post-carding zone.

The zone of the drum 1 defined between the drum-doffer transfer line 16 and the briseur-drum transfer line 14, in the sequence now said and in the direction of rotation of the drum, forms an under-drum zone.

The carding machine further comprises a support element 19, from one side to the other of the width of the drum, to support the components acting on the drum.

The carding machine further comprises at least one suction nozzle unit 20, overlapping the side surface of the drum and suitable for co-operating with the drum to clean the fibre pulled by the latter.

The suction nozzle unit comprises a suction chamber 22 open towards the lateral surface of the drum 1 by means of an inlet aperture 22a and connected to air suction means .

According to a preferred embodiment, the unit 20 comprises a profile 24, having an axial extension parallel to the rotation axis of the drum, which defines and delimits at least partially said suction chamber 22. According to a preferred embodiment the profile 24 is fixed, for example by means of a structure, to the support element 19, so as to maintain a fixed, non- adjustable position when working.

The suction nozzle unit 20 further comprises knife means 30 suitable for acting on the fibre pulled by the drum to separate dirt and impurities from it.

The knife means 30 comprise a knife 32 provided with a sharpened edge 34, projecting towards the lateral surface of the drum, suitable for processing the fibre pulled by the drum interfering mechanically with the impurities present therein, to separate them.

The knife is adjacent to the suction chamber 22 so that the impurities separated from the fibre are aspirated, and in particular at least partially delimits the inlet 22a of the suction chamber 22.

The knife 32 is adjustable, that is to say the position of said knife, and in particular of the working edge 34, can be modified and fixed to regulate how far it protrudes in relation to the lateral surface of the drum. In particular, the knife means 30 comprise a knife support 36 which firmly supports the knife 32 by means of attachment means 38, for example screws.

The knife means comprise knife adjustment mean 40 suitable for being manoeuvred to modify the position of the knife 32 in relation to the lateral surface of the drum, and in particular suitable for acting on the knife support 36.

According to a preferred embodiment, the knife 32 is radially adjustable, by means of the knife screw adjustment means 40, in turn engaged with the support element 19.

The knife support 36 is sealingly engaged with the profile 24, so as to maintain the airtightness of the suction chamber.

In particular, between the profile 24 and the knife support 36 there is a gap 38 needed to allow the reciprocal movement for the adjustment of the knife, and a seal 39 closing said gap 38 outwards.

The suction nozzle unit further comprises adjustment means 50 suitable for being manoeuvred to adjust^' the aperture 22a of the suction chamber 22.

Said adjustment means 50 comprise a shutter element 52, which at least partially delimits the aperture 22a, suitable for being moved to shut off said aperture 22a. Preferably, the shutter element 52 is rotatable between a limit closed position, in which the aperture 22a is completely closed or reduced to its minimum extension (figure 2), and a limit ope position, in which the aperture 22a is at its maximum extension (figure 3) .

Preferably, the shutter element 52 is manoeuvrable by an operator, for example, manually at the axial ends of the drum, for example near the support element 19.

According to a preferred embodiment, the shutter element 52 comprises a main body 54, for example delimited by an at least partially cylindrical outer surface 56, and a protuberance 58, which extends from the main body 56, for example in a direction tangential to the outer surface 56. In particular, the protuberance 58 extends towards the knife 32, so that the movement, and in particular the rotation of the shutter element 52, causes a variation of the aperture 22a.

According to a preferred embodiment the shutter element 52 and the knife 32 define an inlet duct 60 converging towards the suction chamber 22.

In particular, the protuberance 58 of the shutter element 52 has a functional surface 62 which in the limit closed position faces the lateral surface of the drum and which is substantially flat.

In the limit open position the functional surface 62 of the shutter element 52 and the bottom surface 32a of the knife 32 define said inlet duct 60.

In addition, the protuberance 58 has an end surface 64, subsequent to the functional surface 62, inclined in relation thereto.

In the limit closed position the end surface 64 of the shutter element 52 and the bottom surface 32a of the knife 32 define said inlet duct 60.

In addition, preferably, the shutter element 52 comprises a guide branch 59a, projecting from the protuberance 58 and distanced from the main body 54, with the outer surface of which it forms a guide compartment 59b.

The adjustment means 50 comprise an adjustment support 70 which supports the shutter element 52, so as to allow its movement .

The adjustment support 70 is attached at the ends, for example to the support element 19, for example by screws, and co-operates with the profile 24 to delimit the suction chamber 22.

Preferably, the adjustment support 70 is coupled to the profile 24 so as to form a seal.

The adjustment support 70 has a bottom surface 70a, preferably flat, towards the lateral surface of the drum 1, distanced by a predefined amount from the lateral surface of the drum.

According to a preferred embodiment, the adjustment support 70 comprises a seat 72, which the main body 54 of the shutter element 52 is inserted in so as to swivel.

In particular, the surface of the seat 72 co-operates with the cylindrical portion of the outer surface 56 of the main body 54, to guide it in rotation.

Preferably, in addition, the adjustment support 70 comprises a guide 80, which preferably delimits the seat

72 at least partially, suitable for guiding the movement of the shutter element 52.

For example, the guide 80 slides in the guide compartment 59b of the shutter element 52 between the limit open position and the limit closed position, in contact with the guide branch 59a.

For a given position of the knife 32, adjustable by means of the knife adjustment means 40, in the limit open position of the shutter element 52 (figure 2), the aperture 22a has the maximum extension and between the outermost lower edge of the shutter element 52 (in the radial direction) and the bottom surface 70a of the adjustment support 70 there is a maximum drop, for example equal to 0.5 mm.

Such configuration allows a significant suction action, an incisive separation of dirt and impurities from the fibre, also depending on the adjustment of the knife. In addition, for a given position of the knife 32, in the limit closed position of the shutter element 52 (figure 3) , the aperture 22a has the minimum extension and between the outermost lower edge of the shutter element 52 (in the radial direction) and the bottom surface 70a of the adjustment support 70 there is a minimum drop, for example equal to 0.2 mm.

In particular, in such position, the outermost lower edge of the shutter element 52 is defined by the functional surface 62 of the protuberance 58.

Such configuration allows a reduced suction action and a less incisive separation of dirt and impurities, in any case depending on the adjustment of the knife. In other words, the shutter element 52 has an outer cam surface, the rotation of which influences the extension of the aperture 22a of the suction chamber 22 and the drop of the outermost lower edge of said cam surface in relation to the bottom surface 70a of the adjustment support 70.

According to one embodiment variation, a suction nozzle unit 120 according to the invention, comprises a knife support 136 integrated with a cover segment 82 of the drum 1, positioned downstream of said knife support 136 in relation to the rotation of the drum (figure 5a) .

According to a further embodiment variation, similarly to the suction nozzle unit 120, a suction nozzle unit 220 according to the invention, comprises an adjustment support 270 integrated with an adjacent cover segment 82 of the drum 1, positioned upstream of said adjustment support 270 in relation to the rotation of the drum ( figure 5b) .

According to a preferred embodiment the suction nozzle unit 120, 220 is positioned circumferentially alongside the movable flats 6, at the inlet (figure 5a) or outlet (figure 5b) thereof and has a lateral aperture 90 facing towards said movable flats, suitable for the aspiration of the dust raised by said flats.

For example, said lateral aperture 90 is made between the profile 24 and the knife support 136 (figure 5a) or between the profile 24 and the adjustment support 270 (figure 5b) .

According to a further embodiment a suction nozzle unit 320 is without knife means or has fixed knife means, for example consisting of a sharpened edge 24a of the profile 24, projecting towards the lateral surface of the drum 1. The carding machine further comprises functional groups 80, comprising at least one suction nozzle unit 20, 120,220,320 and/or at least one cover segment. 82 and/or at least one carding flat 84.

According to one embodiment variation, the functional unit has the suction nozzle unit at the end of the unit, that is to say, at the outlet of the fibre.

For example, the functional unit 80 comprises, according to the direction of rotation of the drum, the cover segment 82, a plurality of carding flats 84, for example eight in number, and the suction nozzle unit 120 with downstream segment (figure 4a) .

According to a further embodiment variation, the functional unit comprises at least one suction nozzle unit in an intermediate position inside the functional unit .

For example, carding flats 84 variously interspersed with suction nozzle-knife units with adjustable or fixed knife, are provided.

For example, the functional unit 80 comprises, according to the direction of rotation of the drum, the cover segment 82, a pair of carding flats 84, the suction nozzle unit 20, four carding flats 84, the suction nozzle unit 220 with downstream segment (figure 4b) .

According to a further embodiment variation, the functional unit has the suction nozzle unit at the beginning of the unit, that is to say, at the inlet of the fibre.

For example, the functional unit comprises, according to the direction of rotation of the drum, the suction nozzle unit 220 with upstream cover segment, a pair of carding flats 84, the suction nozzle unit 20, a further pair of carding flats 84 and the cover segment 82.

According to yet a further embodiment variation, the functional unit has the suction nozzle unit at the inlet of the unit, that is to say, at the inlet of the fibre. For example, the functional unit 80 comprises, according to the direction of rotation of the drum, the suction nozzle unit 220 with upstream cover segment, a plurality of carding flats 84, for example six in number, and the cover segment 82 (figure 4d) .

Preferably, the suction nozzle unit 20, 120, 220, 320 or functional unit 80 is positioned in the pre-carding zone. According to a further embodiment, the suction nozzle unit 20, 120, 220, 320 or functional unit 80 is positioned in the post-carding zone.

According to yet a further embodiment, the suction nozzle unit 20, 120, 220, 320 or functional unit 80 is positioned in the under-drum zone.

Innovatively, the suction nozzle unit according to the present invention makes it possible to improve the productivity of the carding machine, in that it allows the regulation of the suction action on the fibre pulled by the drum as needed and opportune, for example depending on the type of fibre and the provenance thereof .

Advantageously, in addition, the suction nozzle unit makes it possible to regulate the extraction action of the dirt and impurities as needed, and in particular independently of the suction action.

According to a further advantageous aspect, the suction nozzle unit can be conveniently and efficiently adjusted by the operator, without the dismantling of parts or components to access the regulation devices.

It is clear that a person skilled in the art may make modifications to the suction nozzle unit described above so as to satisfy contingent requirements.

For example, according to one embodiment variation, the shutter element is supported so as to perform an eccentric rotation, for example by virtue of the outer surface of the main cam body.

According to a further embodiment variation, the knife support is adjustable by rotation.

According to yet a further embodiment variation, the adjustment support is adjustable for example by radial translation, rotation or roto-translation .

Such variants are also contained within the sphere of protection as defined by the following claims.

Moreover, the present invention relates to a further suction nozzle of a carding machine on a yarn spinning line .

Such purpose is achieved by a suction nozzle unit made according to claim 18 and depending thereof.

The characteristics and advantages of the further suction nozzle unit according to the invention will be evident from the description below, made by way of a non-limiting example according to the attached figures, wherein:

- figure 7 shows a drum, an input cylinder and an output cylinder of a carding machine, fitted with suction nozzle-knife units according to the present invention, according to another embodiment of the invention;

- figure 8 shows the suction nozzle unit in figure 7, in a configuration of maximum deviation; - figure 9 shows the suction nozzle unit in figure 7, in a configuration of minimum deviation;

figures 10a to lOd show embodiment variations of functional groups comprising at least one suction nozzle unit according to the present invention;

figures 11a, lib and 12 show further embodiment variations of the suction nozzle unit according to the embodiment of figure 7.

According to this embodiment, a carding machine comprises a drum 101 rotatable around a drum axis, provided on the surface with a covering for pulling the fibre in tufts. Moreover, the carding machine comprises an introduction cylinder 102 or briseur, rotating on command and covereded on the surface, counter-rotating in relation to the drum 101, operatively engaged upstream with a feed duct of a feed silo of the fibre in tufts and downstream with the drum 101, to which the fibre is transferred. Moreover, the carding machine comprises an extraction cylinder or doffer 104, downstream of the drum 101. The doffer 104 is covered on the surface, rotating on command and counter-rotating in relation to the drum, and operatively engaged with the surface of the latter, to pick up the fibre.

Moreover, the carding machine comprises a movable flats device 106 comprising a plurality of flats 108, translating along a closed circuit comprising a processing section parallel to the processing surface of the drum 101.

Compared to the drum 101, the processing section of the movable flats device extends from an initial line 1010, defined as the straight line passing through the centre of the drum and the point of the processing circumference of the drum where the translating flats 108 disengage from the drum, and an end line 1012, defined as the straight line passing through the centre of the drum and the point of the processing circumference of the drum where the translating flats 8 begin engagement with the drum. The zone of the lateral surface of the drum between the initial line and the end line is defined the main carding zone.

A straight line passing through the centre of the drum and the centre of the briseur defines a diametrical briseur-drum transfer line 1014, in that, at its intersection with the outer processing surface of the drum, an area is formed in which the fibre migrates from the surface of the briseur to the surface of the drum. The zone of the drum 101 contained between the initial line 1010 and the briseur-drum transfer line 1014 defines a pre-carding zone.

A straight line passing through the centre of the drum and the centre of the doffer defines a diametrical drum- doffer transfer line 1016, in that, at its intersection with the outer processing surface of the drum, an area is formed in which the fibre migrates from the surface of the drum to the surface of the doffer.

The zone of the drum 101 contained between the end line 1012 of the main carding area and the drum-doffer transfer line 1016 defines a post-carding zone.

The zone of the drum 101 defined between the drum-doffer transfer line 1016 and the briseur-drum transfer line 1014, in the sequence now said and in the direction of rotation of the drum, forms an under-drum zone.

The carding machine further comprises a support element 1019, from one side to the other of the width of the drum, to support the components acting on the drum.

The carding machine further comprises at least one suction nozzle unit 1020, overlapping the lateral surface of the drum and suitable for co-operating with the drum to clean the fibre pulled by the latter.

The suction nozzle unit comprises a suction chamber 1022 open towards the lateral surface of the drum 101 by means of an inlet aperture 1022a and connected to air suction means .

According to a preferred embodiment, the unit 1020 comprises a profile 1024, having an axial extension parallel to the rotation axis of the drum, which defines and delimits at least partially said suction chamber 1022.

According to a preferred embodiment the profile 1024 is fixed, for example by means of a structure, to the support element 1019, so as to maintain a fixed, non- adjustable position when working.

The suction nozzle unit 1020 further comprises knife means 1030 suitable for acting on the fibre pulled by the drum to separate dirt and impurities from it.

The knife means 1030 comprise a knife 1032 provided with a sharpened edge 1034, projecting towards the lateral surface of the drum, suitable for processing the fibre pulled by the drum interfering mechanically with the impurities present therein, to separate them.

The knife is adjacent to the suction chamber 1022 so that the impurities separated from the fibre are aspirated,- and in particular at least partially delimits the inlet 1022a of the suction chamber 1022.

The knife 1032 is adjustable, that is to say the position of said knife, and in particular of the processing edge 1034, can be modified and fixed to regulate how far it protrudes in relation to the lateral surface of the drum. In particular, the knife means 1030 comprise a knife support 1036 which firmly supports the knife 1032 by means of attachment means 1037, for example screws.

The knife means comprise knife adjustment means 1040 suitable for being manoeuvred to modify the position of the knife 1032 in relation to the lateral surface of the drum, and in particular suitable for acting on the knife support 1036.

According to a preferred embodiment, the knife 1032 is radially adjustable, by means of the knife screw adjustment means 1040, in turn engaged with the support element 1019.

The knife support 1036 is sealingly engaged with the profile 1024, so as to maintain the airtightness of the suction chamber.

In particular, between the profile 1024, for example at one end thereof, and the knife support 1036 there is a gap 1038a needed to allow the reciprocal movement for adjustment of the knife, and a seal 1039a closing said gap 1038a outwards.

The suction nozzle unit further comprises a deviation element 1070, facing the knife 1032, which acts in conjunction with the profile 1024 to delimit the suction chamber 1022 and at least partially delimits, by a portion thereof, said inlet aperture 1022a.

In particular, the deviation element 1070 is positioned upstream of the inlet aperture 1022 of the chamber 1022 in relation to the direction of rotation of the drum. Moreover, the deviation element 1070 is movable in relation to the profile 1024 and, for example at the end of said profile 1024, is separated from it by a gap 1038b; a seal 1039b is also provided to seal the gap 1038b in an outward direction.

The deviation element 1070 has a bottom surface 1070a, preferably flat, towards the lateral surface of the drum 101.

The suction nozzle unit comprises deviation adjustment means 1080 suitable for being manoeuvred to adjust the deviation between the deviation element 1070 and the lateral surface of the drum, that is to say to adjust the radial distance between the bottom surface 1070a of the deviation element and the bottom surface 1070a.

According to a preferred embodiment, the deviation element 1070 is radially adjustable and the deviation adjustment means 8 are for example a screw, in turn engaged with the support element 1019.

For a given position of the knife 1032, adjustable by means of the knife adjustment means 1040, in the position of maximum deviation (figure 8), the bottom surface 1070a of the deviation element 1070 has a maximum radial distance from the lateral surface of the drum, for example equal to 0.5 mm. Such configuration allows a significant suction action, incisive separation of dirt and impurities from the fibre, also depending on the adjustment of the knife, which proves largely uncovered, that is to say struck by a significant flow of fibre.

Moreover, for a given position of the knife 1032, in the position of minimum deviation (figure 9), the bottom surface 1070a of the deviation element 1070 has a minimum radial distance from the lateral surface of the drum, for example equal to 0.2 mm.

Such configuration allows a limited suction action, a less incisive separation of dirt and impurities from the fibre, also depending on the adjustment of the knife, which proves marginally uncovered, that is to say struck by a limited flow of fibre.

According to one embodiment variation, a suction nozzle unit 1120 according to the invention, comprises a knife support 1136 integrated with an adjacent cover segment 1082 of the drum 101, positioned downstream of said knife support 1136 in relation to the rotation of the drum (figure 11a) .

According to a further embodiment variation, similarly to the suction nozzle unit 1120, a further suction nozzle unit 1220 according to the invention, comprises a deviation element 1270 integrated with an adjacent cover segment 1082 of the drum 101, positioned upstream of said deviation element 1270 in relation to the rotation of the drum (figure lib) .

According to a preferred embodiment the suction nozzle unit 1120, 1220 is positioned circumferentially alongside the movable flats 106, at the inlet (figure 11a) or outlet (figure lib) thereof and has a lateral aperture facing towards said movable flats, suitable for the aspiration of the dust raised by said flats.

For example, said lateral aperture 1090 is made between the profile 1024 and the knife support 1136 (figure 11a) or between the profile 1024 and the deviation element 1270 (figure lib) .

According to a further embodiment a suction nozzle unit 1320 is without knife means or has fixed knife means, for example consisting of a sharpened edge 1024a of the profile 1024, projecting towards the lateral surface of the drum 101.

The carding machine further comprises functional groups 1100, comprising at least one suction nozzle unit 120, 1120, 1220, 1320 and/or at least one cover segment 1082 and/or at least one fixed carding flat 1084.

According to one embodiment variation, the functional unit has the suction nozzle unit at the end of the unit, that is to say at the outlet of the fibre, and is .without intermediate suction nozzle groups.

For example, the functional unit 1100 comprises, according to the direction of rotation of the drum, the cover segment 1082, a plurality of carding flats 1084, for example eight in number, and the suction nozzle unit with downstream segment (figure 10a) .

For example, carding flats 1084 variously interspersed with suction nozzle-knife groups with adjustable or fixed knife are provided.

For example, the functional unit 1100 comprises, according to the direction of rotation of the drum, the cover segment 1082, a pair of carding flats 1084, the suction nozzle unit 1020, four carding flats 1084, the suction nozzle unit 1220 with downstream cover segment (figure 10b) .

According to a further embodiment variation, the functional unit has the suction nozzle unit at the beginning of the unit, that is to say at the inlet of the fibre and at least one suction nozzle unit in an intermediate position inside the functional unit.

For example, the functional unit comprises, according to the direction of rotation of the drum, the suction nozzle unit 1220 with upstream cover segment, a pair of carding flats 1084, the suction nozzle unit 1020, a further pair of carding flats 1084 and the cover segment 1082.

According to yet a further embodiment variation, the functional unit has the suction nozzle unit at the inlet of the unit, that is to say, at the inlet of the fibre, and is without intermediate suction nozzle groups.

For example, the functional unit 1080 comprises, according to the direction of rotation of the drum, the suction nozzle unit 1220 with upstream cover segment, a plurality of carding flats 1084, for example six in number, and the cover segment 1082 (figure lOd) .

Preferably, the suction nozzle unit 120, 1120, 1220, 1320 or functional unit 1100 is positioned in the pre-carding zone .

According to a further embodiment, the suction nozzle unit 1020, 1120, 1220, 1320 or functional unit 1100 is positioned in the post-carding zone.

According to yet a further embodiment, the suction nozzle unit 1020, 1120, 1220, 1320 or functional unit 1100 is positioned in the under-drum zone.

Innovatively, the suction nozzle unit according to this embodiment makes it possible to improve the productivity of the carding machine, in that it allows the regulation of the suction action on the fibre pulled by the drum as needed and opportune, for example depending on the type of fibre and the provenance thereof.

According to a further advantageous aspect, the suction nozzle unit can be conveniently and efficiently adjusted by the operator, without the disassembly of parts or components to access the regulation devices.

For example, the knife support is adjustable by rotation or roto-translation .

According to yet a further embodiment variation, the deviation element is adjustable by rotation or roto- translation .

Such variants are also contained within the scope of protection as defined by the following claims.

Claims

1. Suction nozzle unit (20,120,220,320) for a carding machine on a yarn spinning line, comprising

- a suction chamber (22) connectable to suction means, having an inlet aperture (22a) ;

- means of adjustment (50) comprising a shutter element (52) , which at least partially delimit the inlet aperture (22a) ;

wherein the shutter element (22a) is adjustable to shut off the inlet aperture of the suction chamber (22) .

2. Suction nozzle unit according to claim 1, comprising

- knife means (30) suitable for working on the fibre pulled from a drum of the machine to separate dirt and impurities from it, comprising a knife (32,24a) which at least partially delimits said inlet aperture (22a) .

3. Suction nozzle unit according to claim 2, wherein the knife (30) is adjustable in position.

4. Suction nozzle unit according to claim 3, wherein the knife (30) is radially adjustable.

5. Suction nozzle unit according to claim 3 or 4, wherein the knife means (30) comprise a knife support (36) which firmly supports the knife (32) by means of attachment means (38), said knife support (36) being adjustable in position to adjust the position of the knife.

6. Suction nozzle unit according to any of the previous claims, wherein the shutter element (52) can be rotated on command between a limit closed position, in which the aperture (22a) is completely closed or reduced to its minimum extension, and a limit open position, in which the aperture (22a) is at its maximum extension.

7. Suction nozzle unit according to any of the claims from 2 to 6, wherein the shutter element (52) and the knife (32) define an inlet duct (60) converging towards the suction chamber (22) .

8. Suction nozzle unit according to any of the previous claims, wherein the shutter element (52), comprises a main body (54) delimited by an at least partially cylindrical outer surface, housed so as to rotate in a seat (72), and a protuberance (58) which extends from the main body ( 5 ) .

9. Suction nozzle unit according to any of the previous claims, wherein

the adjustment means (50) comprise an adjustment support (70) which supports the shutter element (52), having a bottom surface (70a) , and wherein

- the shutter element (52) has an outer cam surface, so that

a) in the limit open position, between the outermost lower edge of the shutter element (52) and the bottom surface (70a) of the adjustment support (70) there is a maximum drop, and

b)in the limit closed position,, between the outermost lower edge of the shutter element (52) and the bottom surface (70a) of the adjustment support (70) there is a minimum drop.

10. Suction nozzle unit according to claim 9, wherein the adjustment support (70) comprises a guide (80) suitable for guiding the movement of the shutter element (52) .

11. Suction nozzle unit according to claim 2, wherein the knife (30) is fixed.

12. Suction nozzle unit according to claim 11, wherein the knife consists of a sharpened edge (24a) of a profile (24) which defines the suction chamber (22).

13. Functional unit (80) comprising

at least one suction nozzle unit (20,120,220,320) made according to any of the previous claims; and/or

- at least one fixed cover segment (82) integral with the suction nozzle unit; and/or

- at least one fixed carding flat (84) .

14. Carding machine comprising

- a suction nozzle unit (20,120,220,320) according to any of the claims from 1 to 12;

- a support element (19) positioned externally to the width of the drum (1) and in correspondence with its lateral surface, which supports the suction nozzle unit.

15. Carding machine according to claim 14, wherein the shutter element (52) can be manoeuvred near said support element (19) .

16. Carding machine according to claim 14 or 15, wherein the knife (32) can be adjusted near said support element

(19) .

17. Carding machine according to any of the claims from 14 to 16, wherein the- suction nozzle unit is positioned in the pre-carding area or in the post-carding area or in the under-drum zone.

18. Suction nozzle unit (1020,1120,1220,1320) for a carding machine on a yarn spinning line, comprising

- a suction chamber (1022) connectable to suction means, having an inlet aperture (1022a) ;

- a deviation element (1070) positioned upstream of said inlet aperture (1022a), which at least partially defines said suction chamber (1022) and said inlet aperture (1022a) ;

wherein the deviation element is adjustable to adjust the deviation with respect to a drum (101) of the carding machine .

19. Suction nozzle unit according to claim 18, wherein the suction chamber (1022) is defined at least partially by a fixed profile (1024) at the end of which a gap (1038b) is provided to distance the profile from the deviation element, and a seal (1039b) closing the gap for sealing the profile and the deviation element.

20. Suction nozzle unit according to claim 18 or 19, comprising

- knife means (1030) suitable for working on the fibre pulled by the drum to separate dirt and impurities from it, comprising a knife (1032,1024a) which at least partially delimits said inlet aperture (1022a) .

21. Suction nozzle unit according to claim 20, wherein the knife (1030) is adjustable in position.

22. Suction nozzle unit according to claim 21, wherein the knife (1030) is radially adjustable.

23. Suction nozzle unit according to claim 21 or 22, wherein the knife means (1030) comprise a knife support (1036) which firmly supports the knife (1032) by means of attachment means (1037), said knife support (1036) being adjustable in position to adjust the position of the knife .

24. Suction nozzle unit according to claim 20, wherein the knife (1030) is fixed.

25. Suction nozzle unit according to claim 24, wherein the knife consists of a sharpened edge (1024a) of a profile (1024) which defines the suction chamber (1022) .

26. Functional unit (1100) comprising

- at least one suction nozzle unit (1020,1120,1220,1320) made according to any of the previous claims; and/or

- at least one fixed cover segment (1082) integral with the suction nozzle unit; and/or

- at least one fixed carding flat (1084) .

27. Carding machine comprising

- a suction nozzle unit (1020,1120,1220,1320) according to any of the claims from 18 to 25;

- a support element (1019) positioned externally to the width of the drum (101) and in correspondence with its lateral surface, which supports the suction nozzle unit.

28. Carding machine according to claim 27, wherein the deviation element (1070) can be manoeuvred near said support element (1019) .

29. Carding machine according to claim 27 or 28, wherein the knife (1032) is adjustable near said support element

(1019) .

30. Carding machine according to any of the claims from 27 to 29, wherein the suction nozzle unit is positioned in the pre-carding area or in the post-carding area or in the under-drum zone.