EP3953507B1

EP3953507B1 - Combing machine for a spinning preparation line

Info

Publication number: EP3953507B1
Application number: EP20718777.4A
Authority: EP
Inventors: Luca SOLIANI; Girolamo Prandini
Original assignee: Marzoli Machines Textile SRL
Current assignee: Marzoli Machines Textile SRL
Priority date: 2019-04-11
Filing date: 2020-03-26
Publication date: 2023-03-29
Anticipated expiration: 2040-03-26
Also published as: JP2022527046A; CN113966417B; EP3953507A1; IT201900005608A1; JP7423650B2; CN113966417A; WO2020208454A1

Description

Field of the invention

The subject matter of the present invention relates to a combing machine for a cotton-fiber spinning preparation line.
In a spinning preparation line, after the initial steps of opening and cleaning the fiber, a carding operation is performed by carding machines, after which the fiber takes the form of a sliver.
The carded sliver exiting the carding machine typically undergoes a first draft in a drafting machine, where several slivers are joined together.
A predefined number of slivers, usually numbering 24, 28 or 32, enter a lap-forming machine to create the laps that are processed in a combining machine, in order to obtain a combed sliver in which the fibers are highly parallelized and clean.

State of the art

The basic operations of combing, which in conventional machines of more recent construction follow one another at a rate of 500-550 strokes a minute, are:

intermittent feeding of the carded sliver;
combing, by means of a rotary comb, of the head of the incoming tuft, with the gripper closed;
overlaying and joining the head of the tuft to the sliver previously combed in the preceding cycle, appropriately set back, by means of detaching cylinders during their backward rotation;
combing the tail of the tuft by means of a straight comb of the gripper, with the gripper open;
advancing the combed tuft by means of the detaching cylinders during their forward rotation.

The detaching cylinders, however, have an alternating rotary motion.
To overcome the drawbacks due to the alternating rotary motion of the detaching cylinders, some solutions in which the detaching cylinders have a unidirectional rotary motion have been developed. One solution is shown in document EP-A1-1553219 .
Additional solutions are shown in International Applications PCT/IB2019/050158 and PCT/IB2019/051946 , in the name of the Applicant.
Another combing machine with detaching cylinders having unidirectional rotary motion is shown in DE 515 742 C .

Purpose of the invention

The purpose of the present invention is to create a combing machine, in particular provided with detaching cylinders having a continuous rotary motion (at a constant or variable, but unidirectional speed), that is capable of ensuring a satisfactory level of quality of the combed sliver.
This purpose is achieved by a combing machine made according to claim 1. The dependent claims describe further advantageous embodiments of the invention.

Brief description of the figures

The characteristics and advantages of the combing machine according to the present invention will emerge from the following description, given by way of non-limiting example, according to the accompanying drawings, in which:

Figure 1 shows a schematic view of a combing machine according to the present invention, comprising a plurality of combing heads;
Figure 2 is a schematic representation of the combing head, according to an embodiment of the present invention.

Detailed description of the invention

A combing machine 1 according to the present invention comprises a fixed frame and a plurality of combing heads 2, aligned along a transverse axis X.
In each combing head 2, the sliver being machined advances in a longitudinal direction Y.
Downstream of each combing head 2, a funnel 4 is positioned, thanks to which the combed sliver is condensed into a web N.
The webs from each combing head 2 are deflected by appropriate deviation means 6 and lie alongside one another on a pallet, so as to proceed along a common advancement direction, typically parallel to the transverse direction X.
Each combing head 2 comprises a gripper, provided with a lower jaw, an upper jaw and a straight comb, usually on board the lower jaw.
Furthermore, the gripper comprises a feeding cylinder, which can be operated to rotate intermittently, supported by the lower jaw.
The combing head also comprises, downstream of the gripper, at least one pair of detaching cylinders.
For example, preferably, immediately downstream of and facing the gripper, is a pair 20' of detaching cylinders 20a', 20b' superimposed, preferably in pressure contact, provided with continuous rotary motion (at constant or variable, but not reversible, speed), so as to drag a section of sliver emerging from the jaws, tearing off a tuft of sliver and carrying it downstream.
Preferably, the lower detaching cylinder 20b' is motorized or operated in rotation by means of a kinematic connection with another motorized cylinder, while the upper detaching cylinder 20a', preferably provided with a rubber coating, is in pressure contact with the lower detaching cylinder 20b' and driven in rotation thereby.
According to one embodiment, downstream of the pair 20' of detaching cylinders 20a', 20b' is placed a pair 20 of auxiliary cylinders comprising an upper auxiliary cylinder 20a, preferably motorized or operating in rotation by means of a kinematic connection with another motorized cylinder, and a lower auxiliary cylinder 20b, usually in pressure contact with the upper auxiliary cylinder 20a and preferably driven in rotation thereby.
The auxiliary cylinders 20a, 20b, which have a peripheral speed Vs, have a continuous rotary motion (at a constant or variable, but non reversible speed), such as to draw along a section of sliver offered by the detaching cylinders 20a, 20b, tear off a tuft from the sliver and carry it from upstream to downstream.
According to a preferred embodiment, the combing head comprises an auxiliary device 300, comprising said auxiliary cylinders 20a, 20b and respective auxiliary belts 304a, 304b that run along respective closed paths, defined for example by auxiliary deflectors 306a, 306b, 308a, 308b, such as cylinders, rollers, angular elements and suchlike.
Furthermore, the combing head comprises a main device 26, placed immediately downstream of the auxiliary cylinders 20a, 20b or immediately downstream of the detaching cylinders 20a', 20b', provided with a main, for example rotating, movable surface 28 against which, and in particular against an impact area 29 of said main surface 28, impacts a tuft emerging from the auxiliary cylinders 20a, 20b.
The auxiliary device 300 is suitable for transferring the tuft S' torn off by the detaching cylinders 20a', 20b' to said main device 26.
The main surface 28 is provided with a main speed Va, particularly in the impact area 29.
For example, said main device 26 comprises a main cylinder 30, provided with continuous rotary motion (at constant or variable, but unidirectional, speed), in a clockwise or anti-clockwise direction, having a side surface 30', which constitutes said main surface 28 of the main device 26.
The side surface 30', i.e. the main surface 28, is impermeable to air. In other words, no suction holes or gaps are provided on said surface or, if they are, as in the case of a breathable fabric, they are not connected to air suction means.
The main cylinder 30 usually has a larger diameter than the diameter of the main detaching cylinders 20a, 20b and a peripheral speed Vm, which corresponds to an angular speed Wm.
The peripheral speed Vm of the main cylinder 30 is less than the peripheral speed Vs of the auxiliary cylinders 20a, 20b.
The combing head also comprises a transfer device 40 on which is carried a tuft of sliver web that abandons the main surface 28 of the main device 26, or the side surface 30' of said main cylinder 30; said tuft is carried into a transfer area 42 of said transfer device 40.
Preferably, the transfer device 40 is engaged with the main surface 28 of the main device 26; for example, said transfer device 40 is tangent to the side surface 30' of said main cylinder 30 along an engagement line L.
Preferably, said transfer device 40 is flat around said engagement line L.
Preferably, furthermore, said transfer area 42 of the transfer device 40 is flat.
Having defined an imaginary lower plane of the centers P4 passing through the axis of rotation of the lower auxiliary cylinder 20b and of the main cylinder 30, said lower plane of the centers P4 intersects the side surfaces of the lower auxiliary cylinder 20b and of the main cylinder 30, defining a lower passage 32 passed through by the tuft that detaches from the main surface 28, i.e. from the side surface 30', to be carried onto the transfer device 40.
An imaginary upper plane of the centers P5 is likewise defined, passing through the axis of rotation of the upper auxiliary cylinder 20a and of the main cylinder 30; said upper plane of the centers P5 intersects the side surfaces of the upper auxiliary cylinder 20a and of the main cylinder 30, defining an upper passage 34.
The lower passage 32, through which passes the tuft that detaches from the main surface 28, i.e. from the side surface 30', in order to be carried onto the transfer device 40, is narrower than the upper passage 34.
In other words, the tuft that detaches from the main surface 28, i.e. from the side surface 30', to be carried onto the transfer device 40 passes through the narrower passage (called the outlet passage) of the two passages created by the lower auxiliary cylinder 20b and the upper auxiliary cylinder 20a in relation to the main surface 28 of the main device 26, i.e. the side surface 30' .
The transfer area 42 is positioned facing the lower passage 32, for example upstream of the engagement line L, with reference to the direction of the main speed Va or peripheral speed Vm of the main cylinder 30 on said engagement line L.
Preferably, furthermore, said transfer device 40 is movable, i.e. provided with a predefined support speed Vs in the transfer area 42.
For example, the combing head is provided with a movable mat 50 that travels along a closed path, preferably outside the main cylinder 30, and which, for at least one section, constitutes said transfer device 40.
The speed of the mat 50 in the transfer area 42 corresponds to said support speed Vs and matches the direction of the main speed Va or the peripheral speed of the main cylinder 30 on the engagement line L.
For example, on the engagement line L, the mat 50 is tangent to the main surface 28 or side surface 30' of the main cylinder 30.
Preferably, the mat 50, in order to follow its closed path, winds round at least one deflector cylinder.
The operation of the above-described combing head is illustrated in detail in International Application PCT/IB2019/051946 , the teaching of which is expressly incorporated herein.
The combing head according to the present invention also comprises a drafting device 600, positioned downstream of the gripper, but upstream of the deviation means 6 of each combing head 2, and in particular upstream of the funnel 4 thereof.
In particular, the drafting device 600 is located downstream of the main device 26, or downstream of the main cylinder 30, and is fed by the transfer device 40.
The drafting device 600 comprises a first pair 602 of drafting cylinders 602a, 602b, of which the first lower drafting cylinder 602b is preferably motorized, while the first upper drafting cylinder 602a is engaged under pressure with the first lower drafting cylinder 602b and driven in rotation thereby.
The drafting device 600 also comprises an upper drafting belt 604a, engaged with the first upper drafting cylinder 602a and with a deflector element, for example a roller 606.
The drafting device 600 also comprises a lower drafting belt 604b, engaged with the first lower drafting cylinder 602b and with an additional deflector element, for example a baffle 608.
According to a preferred embodiment, the lower drafting belt 604b coincides with the mat 50 of the transfer device 40.
Preferably the baffle 608 has a T-shaped cross section and a sliding portion 610 having a preferably arched sliding surface 612, on which the lower drafting belt 604b slides.
Preferably, furthermore, the roller 606 is arranged at said sliding surface 612.
The lower drafting belt 604b and the upper drafting belt 604a are in contact with one another for a contact section 614 of their respective paths.
The imaginary plane C passing through the axes of rotation of the first upper cylinder 602a and the first lower cylinder 602b, intersects the contact section 614 of the two belts 604a, 604b on an upstream gripping line P'.
Preferably, furthermore, downstream of said contact section 614, the upper drafting belt 604a separates from the lower drafting belt 604b, before the lower drafting belt 604b is deflected by the baffle 610. In other words, downstream of the contact section 614, the lower drafting belt 604 proceeds further forward, supported by the sliding surface 612, before turning into the return section of the closed path.
The combed sliver that leaves the first pair 602 of drafting cylinders 602a, 602b advances at a predefined upstream speed V1.
The drafting device 600 also comprises a second pair 620 of drafting cylinders 620a, 620b, arranged downstream of the first pair 602.
The second lower drafting cylinder 620b is preferably motorized, while the second upper drafting cylinder 620a is in pressure contact with the second lower drafting cylinder 620b and driven in rotation thereby.
The imaginary plane C'' that contains the axes of rotation of the second upper drafting cylinder 620a and the second lower drafting cylinder 620b contains a downstream gripper line P" along which said second upper drafting cylinder 620a and second lower drafting cylinder 620b are in contact.
The drafting cylinders 620a, 620b of the second pair 620 have a peripheral speed V2, called downstream speed, greater than the downstream speed V1, so that the combed sliver, engaged contemporaneously between the drafting cylinders 602a, 602b of the first pair 602, in the contact section 614 and between the drafting cylinders 620a, 620b of the second pair 620, undergoes drafting.
According to a preferred embodiment, the load with which the drafting belts 604a, 604b are in contact with one another along the contact section 614 is adjustable.
For example, the load that the upper drafting belt 604a exerts on the underlying lower drafting belt 604b is adjustable by using a spring with an adjustable load, operating on the deflector or roller 606 or by using several interchangeable springs, each with a predefined load.
Advantageously, downstream of the upstream gripper line P', the combed sliver, formed by a plurality of overlaid tufts, undergoes controlled drafting in that it is held pressed between the upper belt 604a and the lower belt 604b.
Said belts 604a, 604b, are therefore pressure means suitable for pressing the sliver of overlaid tufts between the upstream gripper line P' and the downstream gripper line P".
According to an embodiment which does not fall under the scope of the claims, said pressure means comprise a lower guide, on which the sliver of overlaid tufts runs and an upper belt that presses the sliver onto the guide.
According to a preferred embodiment, the combing heads of the combing machine are moved by one circular comb shaft for the respective circular combs, one upper detaching shaft and one lower detaching shaft for the detaching cylinders, and similarly for the auxiliary cylinders.
According to a further embodiment, the comb comprises electronic adjustment means suitable for adjusting the speed of the main surface 28, or the speed of rotation of the main cylinder 30. Advantageously, by means of said speed control, it is possible to adjust the extent of the overlap between the tufts.
For the sake of clarity, the above description has been made with reference to a combing head provided with detaching cylinders having unidirectional rotary motion; however, according to a variation which does not fall within the scope of the claims, the drafting device can also be used in the context of a conventional combing machine, provided with detaching cylinders having an alternating rotary motion.
Innovatively, the combing head according to the present invention produces a high-quality combed sliver because the latter has undergone controlled drafting downstream of the main cylinder.

Claims

Combing machine (1) for a cotton-fiber spinning preparation line, comprising at least two combing heads (2), wherein each combing head comprises:
- a gripper and a circular comb, suitable for combing a fiber web;

- at least one pair (20') of detaching cylinders (20a', 20b'), downstream of the gripper, provided with unidirectional rotary motion;

- a drafting device (600), located downstream of the gripper and of the detaching cylinders (20a', 20b'), suitable for drafting the combed web; wherein the drafting device (600) comprises a first pair (602) of drafting cylinders (602a, 602b) kept under pressure along an upstream gripping line (P') and a second pair (620) of drafting cylinders (620a, 620b), downstream of the first pair (602), in pressure contact along a downstream pressure line (P");

characterized in that each combing head comprises deviation means (6), arranged downstream of the gripper and of the detaching cylinders (20a', 20b'), suitable for deflecting a sliver (N), wherein the combed web is condensed, towards a transverse direction (X) of common advancement, along which the slivers of the combing heads are placed mutually side by side;

and in that the drafting device (600) is located upstream of the deviation means (6) and comprises pressure means suitable for pressing the web of overlaid tufts between the upstream gripping line (P') and the downstream gripping line (P"); and the pressure means comprise:
- an upper drafting belt (604a), engaged with the first upper drafting cylinder (602a) and with a deflector element, for example a roller (606); and

- a lower drafting belt (604b), engaged with the first lower drafting cylinder (602b) and with a further deflector element, for example a baffle (608);

wherein said belts (604a, 604b) run along respective closed paths and are in contact with each other along a contact section (614) downstream of the upstream gripping line (P').
Combing machine according to claim 1, wherein the drafting device is located upstream of a funnel (6) for condensing the web.
Combing machine according to claim 1, wherein the drafting cylinders (620a, 620b) of the second pair (620) have a peripheral speed greater than the peripheral speed of the drafting cylinders (602a, 602b) of the first pair (602) .
Combing machine according to claim 1, wherein the baffle (608) has a sliding surface (612) which slides in support of a portion of the lower drafting belt (604b), said sliding surface (612) being preferably arched.
Combing machine according to claim 4, wherein the contact section (614) overlays at least partially the sliding surface (612) of the baffle (608).
Combing machine according to claim 5, wherein the contact section (614) overlays only partially the sliding surface (612) of the baffle (608).
Combing machine according to any one of the preceding claims, wherein the roller (606) is arranged along the sliding surface (612).
Combing machine according to any one of the preceding claims, wherein the diverter or roller (606) operates on the upper belt (604a) with an adjustable load.
Combing machine according to claim 8, wherein said load is adjustable by a spring operating on the diverter or roller (606).
Combing machine according to any one of the preceding claims, wherein each combing head comprises:
- the at least one pair (20') of detaching cylinders (20a', 20b') in contact with each other, suitable for tearing off in succession tufts of fiber from a fiber web and transferring them downstream at a transfer speed;

- a main device (26) provided with a main surface (28) movable at a predefined speed lower than the transfer speed, said main surface (28) being configured so that said tufts impact successively against an impact zone (29) of said main surface (28) and are partially overlaid, forming a web consisting of partially overlaid tufts;

- a transfer device (40) which collects and moves the web consisting of partially overlaid tufts;

- wherein the drafting device (600) is placed downstream of the transfer device (40) and fed thereby with said web consisting of partially overlaid tufts.
Combing machine according to claim 10, wherein
- the transfer device (40) comprises a translatable mat (50); and

- the lower drafting belt (604b) coincides with the mat (50) of the transfer device (40).
Combing machine according to claim 10 or 11, comprising an auxiliary device (300), arranged between the pair (20') of detaching cylinders (20a', 20b') and the main device (26) .
Combing machine according to any one of claims 10 to 12, wherein the main device (26) comprises a main cylinder (30) provided with continuous rotary motion, at constant or variable speed, wherein a side surface (30') of the main cylinder (30) constitutes said main surface (28).
Combing machine according to any one of claims 10 to 13, wherein the main surface (28) is impermeable to air.