ITMI20120638A1 - SEPARATION DEVICE FOR POWDERS FROM FILACCI FOR THE COLLECTION AND RECOVERY OF ROCKING AND WINDING MACHINES WITH SUCH A DEVICE - Google Patents

Description

DEVICE FOR SEPARATING THE DUST FROM THE FILACES

FOR THE COLLECTION AND RECOVERY OF SCRAPS OF

WINDING AND WINDING MACHINE WITH THIS DEVICE

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The present invention refers to a device for separating the powders from the lint for the collection and recovery of the scraps produced during the winding process by the units that make up the automatic winder.

In particular, the object of the present invention is to provide a particularly functional and alternative device to the devices known today suitable for separating the powders from the lint for the collection and recovery of the scraps produced during the winding process.

In industrial practice, the yarn production technique is largely prevalent in a spinning stage followed by a winding stage in which the yarn is unwound from its spool, purified of its defects and rewound into a package. The winding machines are in fact made up of a plurality of winding units aligned along the front of the machine and equipped with common control and service equipment. Among these common service equipment are the devices for preparing the bobbins to be unwound in the winding units.

The scheme of a winding unit is illustrated in its essential components in figure 1 which shows the path of the yarn 2 from the lower spool 1 to the upper collecting spool 12, as follows:

- 3 group of wire guide members,

- 4 the thread presence detector sensor, - 5 thread tensioner 5,

- 6 end splicing device, currently thread splicing, served by

- 9, 10 suction nozzles for capturing and delivering the ends,

- 11 clearer,

- 12 collection spool, driven in rotation by the - 13 roller, and supports supported with

- 14 the bobbin arm,

- 15 spool positioning pin 1,

- 20 one or more suction outlets in the vicinity of the spool 1 to eliminate impurities, substantially consisting of hairiness and fibrils that develop with the winding in operation, currently referred to as â € dust removalâ €.

Both the discontinuous and high head vacuum service, for the recovery of the ends with the nozzles 9 and 10, and the continuous and low head service, for the dust removal with the nozzles 20, is carried out with an individual vacuum cleaner 22 for each of the winding units aligned along the front of the machine.

This aspirator consists of a rotary aspirator with a centrifugal impeller 25 driven by an electric motor 26 â € œbrushlessâ € driven in frequency by the control unit 16 of the winding unit.

The nozzle 20 of the dust removal service with continuous low-vacuum suction is connected with a duct 30 to the suction unit of the winding unit, intercepted with a gate 31, controlled by the control unit 16 of the winding unit. winding unit and normally held open during the normal winding process.

The outlets 9 and 10 work in discontinuous with high depression suction during the interruptions of the normal winding. They are respectively connected with a duct 34 to the suction unit 22 of the winding unit, intercepted with a gate 35, controlled by the control unit 16 of the winding unit and normally kept closed during the normal process winding. The gate 35 is opened only on the occasion of the joining interventions. Ultimately, the individual suction unit 22 that equips the single winding unit 23 serves either the low-vacuum dust removal service duct 30 or the high-vacuum suction duct 34.

The different vacuum values required for the two alternative suction services are obtained by operating the centrifugal fan 22 at different speeds, which has characteristic curves of the suction depression ∠† P which varies in inverse ratio of the volume flow, according to a beam. of parallel and increasing curves with the increase in rotation speed.

The two ducts 30 and 34 of each winding station are connected to a common filter 50, individual for each winding station, which has the function of retaining the material collected and transported by suction and in particular retains both the impurities of the dust removal collected with the winding in operation, and the pieces of yarn, the so-called â € œfilmsâ €, removed by the suction of the aspirator 22, when it is connected to the outlets 9 and 10 and operated at high depression with the winding interrupted.

In each winding station, the individual filter 50 can be equipped with a single filtering septum of fine mesh which retains all the material: both impurities and lint.

As can be seen in the embodiment shown in the detail of Figure 2 in an axonometric view, the individual filter 50 is made with a filtering chamber, with an underlying hopper 55 for collecting the separated lint. The filtering chamber is equipped with a coarse mesh filtering septum 51 which retains the â € œfilmsâ €, removed by the high vacuum suction by the aspirator 22, when it is connected to the outlets 9 and 10 and operated at high depression.

This coarse mesh filtering septum has a hole size of the order of 20 mesh.

As shown, the filtering septum 51 of the filter 50 is preferably arranged to receive from the bottom the flow of the fluid containing the material to be separated, so that, when the high vacuum suction flow ceases, most of the coarse material intercepted and retained by the filtering septum 51 falls spontaneously downwards into the underlying hopper 55, freeing the filtering septum 51.

Generally speaking, the quantity of material to be retained is mainly made up of lint. The linear dimension of the yarns can in fact range from a few centimeters, in the normal preparation of the yarn splice, up to about ten meters and even more, due to the long defects of the yarn count detected with the clearer. Again in general, dust removal impurities have an average size of the order of a millimeter or a little more.

In industrial practice, the material separated and recovered with filters is generally recycled to carding, to recover the fibers that make up the lint. In such processing, the impurities and short fibers possibly present in the recovered material are separated and removed, keeping only the fibers of acceptable length in processing.

From the bottom of the filters 50, which equip the winding stations, the accumulated material is periodically discharged respectively with ducts 53, intercepted with a gate 54, which meet in a common discharge manifold 70. On the opposite upper side, the filters 50 are equipped with a bleed valve 57, which is opened for the operations of discharging the material accumulated in the filters 50. The opening of these bleed valves 57 preferably isolates the filter 50 from its aspirator 22. Figure 3 illustrates the complex of the winding scraps collection system. All the individual outlets 53 of the winding units 23 are connected to a common manifold 70, which collects all the separated material in the respective filters 50.

The spool preparation devices 63 shown here only schematically can also be advantageously connected to the collector 70. These devices generate a significant amount of residues of wire lengths, sucked with an individual aspirator 64, deposited in mesh filters 65 and discharged with a duct 68, with a scheme equipped with discharge gate valves 66 and vent valves 67 completely similar to that of the filters 50 of the winding unit according to Figure 1.

All the filters 50 and 65 are connected with the manifold 70 to a collective system for collecting their scraps, consisting of a small size duct which is arranged along the machine and which receives the flow coming from all the winding units 23 and, preferably, also by the spool preparation devices 63. The manifold 70 is served by a high-depression aspirator 71, which provides for the periodic discharge of the filter material with pneumatic transport to a general filter 80 which is described in greater detail in figures 4 and 5. To avoid clogging, the speed of transport in duct 70 is kept around 20 m / sec.

The need to unload the material retained by the filters is very variable, depending on the yarns treated in the winder. Generally speaking, the higher discharge frequency is required by the spool preparation devices 63 which require their filters 65 to be cleaned even every 10-20 minutes, in the order of magnitude of a few hundred prepared spools.

The filters 50 that equip the winding stations 23, on the other hand, generally require cleaning with a period of the order of magnitude of an hour, in the case of filters with a single filtering septum of fine mesh which retains all the material: both powders and lint. If the filters 50 are made with double filtering chambers in series, this cleaning frequency is reduced, increasing the intervals between one cycle and the next by approximately 40-50%, unless very yarns are processed. hairy.

This cleaning is carried out for a few winding stations at a time and preferably for one filter 50 at a time while its winding unit 23 is in operation. The operation takes a few seconds and takes place, for the winding units 23, first by opening their bleed valves 57, preferably isolating their filter 50 from the aspirator 22, closing the valves 31, 35 towards the unit winding 23 and then opening the discharge valve 54 on the duct 53, with the aspirator 71 in action. In this way it is avoided that the cleaning of the filter affects the winding in its normal operation. The suction with the aspirator 71 draws air from the vents 57 and empties the filters 50 of the accumulated material, bringing it into the general filter 80 through the manifold 70.

According to the invention, the general filter 80 is made with classification of the material in a multi-cyclone system.

In particular, as illustrated in greater detail in Figure 4 as an overall diagram, this multi-cyclone system comprises a double cyclone device 81 for separating the dust from the lint and a single cyclone device 91 for processing the outgoing air stream. from the double cyclone 81 to abate the dust ..

In Figure 5 the cyclones are shown in section to describe their operation.

With reference to Figures 4 and 5, the double cyclone device 81 upstream and the single cyclone device 91 downstream are placed in depression with the aspirator 71.

The double cyclone device 81 comprises a central annular portion 84 and two cone-shaped, or frusto-conical, portions 82A and 82B arranged above and below the annular portion 84.

As will be further detailed, in the cone portion 82A arranged below the central annular portion 84 a descending cyclone motion is imparted to the lint, while in the cone portion 82B arranged above the central annular portion 84 a motion is imparted to the powders with an ascending cyclone, thus effectively dividing the dust from the lint.

The double cyclone device 81 is fed by duct 70 with a current of sucked air containing both lint and other impurities coming from filters 50 and 65 which are gradually cleaned, opening their vents 57 and 67 and their gate valves 54 and 66.

The current to be filtered is introduced discontinuously into the double cyclone device 81 in the upper lower cone portion 82A immediately below the central annular portion 84.

In particular, the duct 70 feeds the current to be filtered into the double cyclone device 81 in a tangential direction, generating a descending spiral motion due to gravity towards the lower cone portion 82A.

In particular, the outlet section of the duct 70 has a circular section.

As already mentioned above, the filter cleaning operation is carried out for one or a few filters at a time. Therefore the arrival of the material to be classified is discontinuous and pulsating.

Due to the effect of the centrifugal force, the lint and the particulate of larger dimensions, due to their greater inertia compared to the powders, come into contact with the internal conical walls of the lower cone portion 82A.

After hitting the walls, the lint slows down their cyclonic motion and due to the effect of gravity they slide and accumulate at the bottom of the lower cone 82A, which therefore acts as a conical hopper, from which it is periodically discharged with the gate 83.

Advantageously, the lint separated from the powders can be recycled.

Due to the pressure difference between the tangential inlet opening 85 and the upper outlet opening 86, the powders, much lighter than lint, reverse the direction of their motion and rise with an ascending spiral motion along the upper cone 82B until to the discharge opening 86 aligned with the cyclone 81 up to the pipe 87.

The conical conformation of the upper portion 82B has the double technical effect of helping the creation of the ascending vortex in charge of capturing the dusty effluent and, once created, stabilizing the vortex itself.

In fact, dusty particles which rise with a spiral motion with directives not perfectly aligned with the outlet duct 86 are conveyed towards this outlet 86.

However, it may still happen that the undesired descending motion of the dusts occurs in part where the dusty pollutants are endowed with a high molecular cohesive force, or there has not been a complete separation of the inverse coaxial internal vortices.

Furthermore, this undesired motion of descent of the powders occurs when vortices are established with an axis not aligned with the main output axis.

Of course, even if the intensity and turbulence of the vortex decrease, the dusty gas can return downwards.

Taking into account the pulsating and discontinuous feeding of the material to be separated, classifying the formation of cyclonic vortices is not immediate and requires a certain interval of time to stabilize and function correctly.

In order both to prevent such undesired descending motions of the dusty portion towards the lower conical portion 82A and to obtain a rapid formation of a stable vortex, according to the present invention the upper cone portion 82B immediately above the annular portion 84 comprises primary nozzles 88 for the introduction of compressed air flows inside the double cyclone 81.

As an example, the supply pressure of the nozzle with compressed air is between 4 - 6 bar and has a flow rate for each separation cycle of approximately 250 Nl.

Said nozzles 88, also defined as over-feeders, feed compressed air in tangential motion into the upper cone portion 82B, in such a motion as to trigger, feed and generate new swirling flows of tangential turbulent nature, during the operating cycle.

This swirling overfeeding increases the swirling motion generated by the duct 70 optimizing the separation of the lint, pushed with more force towards the internal walls of the lower conical portion 82A, and of the powders, more separated by turbulence from the lint. Once the cyclone has formed correctly, the air intake with 88 nozzles can also be interrupted.

Finally, the upper conical portion 82B near the outlet 86 comprises a diffuser of compressed air 104 for discharging the double cyclone 81.

Said diffuser 104 is activated only at the end of the working cycle to favor the unloading of the yarns from the hopper by pneumatic thrust.

As also illustrated in Figure 5, the flow of the duct 87 is introduced into the single cyclone device 91, in particular in its lower conical part 92 and with tangential direction in the opening 94. In a similar way to what has been described previously, also here it is possible to generates a downward spiral motion. As a result of the centrifugal force, the medium-sized particulate leaves the flow, by inertia it comes into contact and brakes against the internal conical walls of the cyclone: due to the effect of gravity the medium particulate slips and accumulates on the conical hopper bottom 92, from the which is periodically discharged with the gate 95. Here too, the flow of air containing the finest particulate reverses the direction of its motion and spirals upwards in the upper part 93 of cyclone 91. Such upper part 93 is cylindrical in shape and, in its central part, is occupied by a filter cartridge 96, which intercepts the ascending flow and breaks down and retains the residual particulate.

The hole pattern of the filter cartridge is of the order of 15 µm. This filtering cartridge is preferably cylindrical, in common axis with cyclone 91, equipped with a blind bottom and a blind upper crown, in order to force the air flow to pass through its cylindrical filtering surface, with the indicated flows. with the arrows, and then to exit from the upper opening 100 towards the aspirator 71 and its discharge to the atmosphere.

Above the cartridge 96 there can be placed a diffuser of compressed air for washing the cartridge, connected to the service compressed air.

During the cleaning operations of the individual filters 50 and 65 of the winding machine, the pressure drop, that is the differential pressure, between the upstream and downstream of the cartridge 96 is constantly checked, for example with the differential pressure gauge. When this measure reaches a predetermined value, at the end of the cleaning cycle the aspirator 71 is stopped and its drain is closed. The cartridge 96 is then cleaned by simultaneously opening the solenoid valve and the gate 95 of the hopper 92 and injecting compressed air with the diffuser. In this way a â € œbackwashingâ € from the inside to the outside is carried out, which releases the particulate matter retained on the external surface of the cartridge 96.

The individual filters 50 are cleaned one at a time by opening in sequence their valves 54 and their respective bleed valves 57. For the filters 65 of the preparation devices 63 the procedure is entirely the same. With the aspirator 71 a suction depression of 10-13 kPa is exerted, that is 1000-1300 mm of water column. These depression values refer to the depression exerted in the filters 50 and 65 to be cleaned, while the depression values in the downstream members are affected by the pressure drops of the overall circuit.

The device according to the present invention for separating the powders from the lint for the collection and recovery of the scraps produced during the winding process is an alternative and particularly functional solution with respect to the currently known devices designed for the same purpose.

Claims (10)

CLAIMS 1) Winding machine of the type comprising a plurality of winding units (23) where each of said winding unit (23) is served by an aspirator (22) alternately with continuous low vacuum suction with winding in operation, for the service of removal of impurities and hairiness of the yarn, or dust, and discontinuous suction at high depression for the elimination of the pieces of yarn, or lint, deriving from the repair and junction of the yarn with interrupted winding, each of said individual aspirators (22) being equipped with a filter (50), all said filters being connected through a common duct (70) to a common general filter (80) for collecting the reeling scraps of the multi-cyclone type comprising in series and, in depression with an aspirator (71), a double cyclone device for separating the lint from the dust and a filter device for said dust coming out of said double cyclone device , characterized in that the double cyclone device (81) for separating the lint from the dust comprises a central annular portion (84) and two truncated conical portions (82A, 82B) respectively lower and upper arranged on the opposite sides of said annular portion ( 84) inviting the generation of two cyclones respectively of the lint and dust and conveying them from said central portion (84) to the reduced diameter outlet openings (86, 89) of said two truncated conical portions (82A, 82B ). 2) Winding machine according to claim 1 characterized in that said common duct (70) introduces said residues into said double cyclone device (81) with tangential motion in correspondence with said lower frusto-conical portion (82A). 3) Winder according to any preceding claim characterized in that the outlet section of said duct (70) in said double cyclone device (81) has a circular section. 4) Winding machine according to any preceding claim characterized in that it comprises primary nozzles (88) for introducing tangential flows of compressed air inside said double cyclone device (81). 5) Winding machine according to claim 4 characterized in that said primary nozzles (88) introduce tangential flows of compressed air in correspondence with said upper truncated-conical portion (82B). 6) Winding machine according to any preceding claim characterized in that it comprises a diffuser for the introduction of compressed air (104) to discharge into said double cyclone device (81) in correspondence with said upper truncated conical portion (82B) in proximity to said outlet mouth (86). 7) Double cyclone device (81) fed by winding scraps for the separation of the powders from the lint comprising a central annular portion (84) and two truncated conical portions (82A, 82B) respectively lower and upper arranged on opposite sides of said annular portion (84) for the generation of two cyclones respectively of the lint and dust and for conveying them from said central portion (84) to the reduced diameter outlet openings (86, 89) of said two truncated conical portions ( 82A, 82B). 8) Double cyclone device (81) according to claim 7 for the classification of lint from powders with pulsating or discontinuous feeding characterized by the fact of comprising primary nozzles (88) for introducing tangential flows of compressed air inside said double cyclone (81). 9) Double cyclone device (81) according to claim 8 characterized by the fact that said primary nozzles (88) introduce tangential flows of compressed air in correspondence with said upper frusto-conical portion (82B). 10) Double cyclone device (81) according to any one of claims from 7 to 9, characterized by the fact of comprising a diffuser for the introduction of compressed air (104) to discharge the double cyclone (81) in correspondence with said upper truncated cone portion (82B) in proximity of said outlet mouth (86).