EP2481700B1

EP2481700B1 - System for collecting winding scraps

Info

Publication number: EP2481700B1
Application number: EP20120152946
Authority: EP
Inventors: Roberto Badiali; Mauro Ceolin; Simone Sacilotto; Mauro Querenghi
Original assignee: Savio Macchine Tessili SpA
Current assignee: Savio Macchine Tessili SpA
Priority date: 2011-01-31
Filing date: 2012-01-27
Publication date: 2014-01-29
Anticipated expiration: 2032-01-27
Also published as: ITMI20110112A1; CN102616610B; IT1403662B1; CN102616610A; EP2481700A1

Abstract

Device for collecting scraps produced by a winder both for dust removal and for lengths of thread, wherein the winding units (23) are served by single aspirators (22) that individually equip each winding unit, and are each equipped with a pair of filters (50,51) for separating the dust and the lengths of thread, arranged in parallel and operating alternately. All filters are connected through a common duct (70) to a common inertial filter (80) for collecting the winding scraps that periodically discharges and receives the material held by such filters, one at a time and separately for each material.

Description

The present invention refers to a device for collecting scraps produced in the course of the winding process by the units that make up the automatic winder.
In industry, the technique of producing yarns in a spinning stage is widespread, followed by a winding stage wherein the yarn is unwound from its spool, cleaned of its defects and rewound in a reel. Indeed, spoolers consist of a plurality of winding units aligned along the front of the machine and equipped with common control and service apparatuses. Among such common service apparatuses there are devices for preparing the spools to be unwound in the winding units.
As already described in the previous Italian patent application IT 2009A2013 in the name of the same Applicant, corresponding to the late published document EP 2 322 458 A1 falling under Article 54(3) EPC, the diagram of a winding unit is illustrated in its essential components in figure 1 that shows the path of the thread 2 from the lower spool 1 to the upper collecting reel 12, as follows:

3. group of thread guide members 3,
4. the sensor for detecting the presence of the thread,
5. thread tightener 5,
6. end joining device, commonly known as thread joiner, served by
9,10. suction mouths for catching and delivering the ends,
11. slubcatcher,
12. collecting reel, actuated in rotation by the
13. roller, and rest supported with
14. the reel-holding arm,
15. spool positioning pin 1,
20. one or more suction mouths nearby the spool 1 to eliminate the impurities and the dusts that develop while the winding is in function, commonly known as "dust removal".

Again according to the quoted application IT 2009A2013 in the name of the same Applicant, both the discontinuous and high head suction service, for recovering the ends through the mouths 9 and 10, and the continuous low head service, for dust removal through the mouths 20 are carried out through an individual aspirator 22, one for each of the winding units aligned along the front of the machine. Such a suction unit consists of a rotary aspirator with a centrifugal impeller 25 actuated through a brushless electric motor 26 controlled in frequency by the control unit 16 of the winding unit.
The mouth 20 of the dust removal service with continuous low depression suction is connected through a duct 30 to the suction unit of the winding unit, intercepted by a slide valve 31, controlled by the control unit 16 of the winding unit and normally kept open during the normal winding process. The mouths 9 and 10 work discontinuously with high depression suction during the interruptions to normal winding. They are respectively connected through a duct 34 to the suction unit 22 of the winding unit, intercepted by a slide valve 35, controlled by the control unit 16 of the winding unit and normally kept closed during the normal winding process. The slide valve 35 is opened on occasion of the joining interventions. Basically, the individual suction unit 22 that equips the single winding unit 23 serves either the duct 30 of the low depression dust removal service or the duct 34 of the high depression suction.
The different depression values required for the two alternative suction services are obtained by actuating the centrifugal aspirator 22 at different speeds, which has characteristic curves of the suction depression ΔP that varies inversely to the flow rate in volume, according to a band of parallel curves increasing with the increase in rotation speed, as already described in the quoted application IT 2009A2013 in the name of the same Applicant.
According to the present invention the two ducts 30 and 34 of each winding station are each equipped with own filter that has the function of holding the material drawn and transported through the suction.
In every winding station, onto the duct 30 of the dust removal an individual filter 50 is placed with fine mesh filtering septum that holds the dusts and the hairs of the thread that are released in the unwinding of the spool 1 and are drawn back by the aspirator 22, when it is connected to the mouths 20 and actuated at low depression.
In every winding station, onto the duct 34 an individual filter 51 is placed with coarser mesh filtering septum that has the function of holding upstream the lengths of thread, the so-called "fluffs", removed by the high depression suction by the aspirator 22 when it is connected to the mouths 9 and 10 and actuated at high depression. The linear size of the fluffs can range from tens of centimetres, in the normal preparation of the joining of the thread, up to tens of metres and even more, due to long defects of the count of the yarn detected with the slubcatcher.
The two individual filters 50 and 51 are connected to the suction manifold of the aspirator 22 through two fittings 30' and 34' respectively and they operate alternately. During the filtering of the sucked air, the material transported is stopped by their filtering septums and, once the suction stops, falls and collects on the bottom of the filter.
From the bottom of the two filters 50 and 51, the material thus collected is periodically discharged, respectively through two ducts 53 and 54, intercepted with two slide valves 57 and 58, which then join up in a common discharge duct 59. On the opposite upper side the two filters 50 and 51 are equipped with venting valves 60 and 61 for the discharging operations of the collected material. The opening of such venting valves 60,61 preferably isolates their filter 50,51 from the aspirator 22.
Figure 2 illustrates the assembly of the system for collecting winding scraps.
All of the individual discharges 59 of the winding units 23 are connected to a common collector 70, which collects all of the separated material in the respective filters 50 and 51.
To the collector 70 can also advantageously be connected the devices 63 for preparing the spools, for example as described in patent application IT 2009 A 2011 and here shown schematically. Such devices generate a significant quantity of residual yarn lengths, sucked through an individual aspirator 64, deposited in mesh filters 65 and discharged through a duct 68, with a scheme equipped with discharge and venting slide valves 66 and 67 entirely analogous to that of the filters 51 of the winding unit according to figure 1.
All filters 50, 51 and 65 are connected through the collector 70 to a collective system for collecting their scraps, consisting of a small sized duct that is arranged along the machine and that receives the flow coming from all winding units 23 and, preferably, also the devices 63 for preparing the spools. The collector 70 is served by a high depression aspirator 71, which provides for the periodical discharging of the material of the filters through pneumatic transportation to an inertial filter 80 that is described in greater details in figures 3A and 3B.
The needs of discharging the material held by the filters is highly variable, according to the yarns treated in the winder. As a general rule, a greater frequency of discharging is required by devices for preparing the spools that require the cleaning of their filters even every 10-20 minutes, in the order of magnitude of a few hundreds of spools prepared. The coarse mesh filters 51 that hold the fluffs, produced by the joining of the threads and by the elimination of defective sections, generally require cleaning with a period of the order of magnitude of an hour. The filters 50 for fine dusts - unless it concerns very hairy yarns - require cleaning with a period of the order of magnitude of a work shift.
According to a preferred embodiment of the invention, the periodic cleaning of the filters is carried out firstly for one kind of material, for example the fluffs for all filters 51 and 63, and then for the other material. Such cleaning is preferably carried for one filter at a time while its winding unit 23 is operating. The operation takes a few seconds and is carried out, for the winding units 23, firstly by opening the venting valves 60 or 61, closing the valves towards the winding unit 31 or 35, thus preventing the cleaning of the filter 50,51 from affecting the winding in its normal operation, and then opening the venting valve, 57 or 58, of the duct 53 or 54, with the aspirator 71 in action. Its suction draws air from the vents, 60 or 61, and empties the filters of the material collected taking it into the inertial filter 80.
In greater details, figure 3A illustrates an outer isometric view of the inertial filter 80, whereas figure 3B shows the casing of the filter in section to show its internal separation into two filtering parts, one for the fluffs and the other for the fine dust.
With reference to figure 2, the filter 80 consists of a parallelepiped casing divided into two filtering chambers, respectively indicated with 81 for the fluffs and with 82 for the dusts and separated with a hermetic wall 83. The two filtering chambers 81 and 82 are placed under depression by the aspirator 71 alternately, opening or closing the intercepting valves 84 and 85 arranged on the ducts 86,87 which connect the two filtering chambers 81,82 to the suction side of the aspirator 71. The two valves 84 and 85 are actuated through the relative actuators 84A,85A by the control unit of the winder for the cleaning operation of the individual filters that equip the winding stations that make up the winder.
The left filtering chamber 81 for the fluffs is divided into a central part 91 and into two side parts 92, separated by two coarse mesh filtering walls 93 that hold the lengths of thread. The two side parts 92 are connected to the aspirator 70 through the opening 94. When proceeding to the cleaning of the individual filters 51 of the winding stations 23, or of the filters 65 of the devices 63 for preparing the spools, it is preferable to operate in sequence to clean one filter at a time, keeping the aspirator 71 in function with the valve 84 open and the valve 85 closed. In this way the fluid carried by the duct 70 enters the filtering chamber 81; the chamber 82 is not involved by the flow and remains inactive.
The individual filters 51 are cleaned one at a time by opening their valves 58 and their respective venting valves 61 in sequence. For the filters 65 of the preparation devices 63 the procedure is totally analogous. Through the aspirator 71 a suction depression of 10-13 kPa or 1000-1300 mm of water column is applied. Such depression values refer to the depression applied in the filters 50, 51 and 65 to be cleaned, whereas the depression values in the members downstream are affected by the load losses of the overall circuit.
In order to avoid clogging, the transport speed in the ducts is kept around 20 m/sec. Near to the inertial filter 80 the duct 70 splits into two branches 73 and 74. The branch 73 enters the filtering chamber 81 of the fluffs on the opposite side to the blind separating wall 83 and ends with a converging nozzle 75 to accelerate the speed of the transport air and of the material transported, i.e. the fluffs. The material thus accelerated hits the blind bottom of the wall 83, loses its kinetic energy and falls onto the bottom of the chamber 81, whereas the transport air passes through the filtering walls 93, enters the two side parts 92, passes through the openings 94 and the discharge ducts 86 towards the aspirator 71 and discharges from the delivery side 95 of the aspirator 71. The filtering walls 93 are arranged parallel to the direction of the flow and are not directly hit by the material transported. On the bottom of the filtering chamber 81 an opening gate 97 is placed for periodically discharging the filtered material consisting of the fluffs.
The filtering surface consisting of the meshes 93 can be further increased by joining the two side spaces 92 in the upper part with an upper space 96 delimited through a mesh septum 93 arranged in the upper part of the space 91, as shown schematically in figures 2 and 3A.
The right filtering chamber 82 for the dusts is also divided into three parts: a central part 101 and two side parts 102, separated by two fine mesh filtering walls 103 that holds the dusts and the hairs of the thread. The two side parts 102 are connected to the aspirator 70 through the opening 104. When proceeding to clean the individual filters 50 of the winding stations 23 it is preferable to operate in sequence to clean one filter at a time, keeping the aspirator 71 in function with the valve 85 open and the valve 84 closed. In this way the fluid carried by the duct 70 enters the filtering chamber 82 of the dusts; the chamber 81 of the fluffs remains inactive.
The individual filters 50 are cleaned one at a time by opening their valves 57 and their respective venting valves 60 in sequence. In order to discharge and transport the dusts it would be sufficient to have depression and speed values lower than those required for the fluffs; however, in order to operate for short time periods, through the aspirator 71 it is possible to operate in the same field of values used to clean the filters 51 from the fluffs.
In order to obtain a lower speed of the fluid arriving into the filtering chamber 82 of the dusts it is sufficient for the branch of duct 74 to be made with a greater diameter, for example to obtain a transport speed in the ducts of around 10 m/sec. The branch 74 of the transport duct enters from the upper side the filtering chamber 82, which constitutes a calm area wherein the transport air of the dusts slows down substantially: a part of the dust deposits immediately in the bottom of the chamber 82 and the rest of the dusts deposits onto the fine mesh filtering septums 103, whereas the transport air passes beyond through the openings 104 and the discharges 87 towards the aspirator 71 and discharges from the delivery side 95 of the aspirator 71. On the bottom of the filtering chamber 82 an opening gate 107 is placed for periodically discharging the filtered material consisting of the dusts. When the suction through the aspirator 71 stops, a prevalent portion of the dust deposited on the filtering septum 103 falls and collects on the bottom of the filter.
According to a preferred embodiment of the present invention the suction device 71 is equipped with an impeller that can be actuated in counter-rotation to generate a counter-pressure, for example with a lateral channel impeller. During the discharging operations of the inertial filter 80, by opening the lower gates, such a counter-pressure facilitates the fall of the material still sticking to the mesh filtering septums 93 and 103.
One of the significant advantages of the inertial filter 80 is the fact that the filtering meshes 93 and 103, which make up the separating septums of the transported material, are not hit directly by the material to be separated, thus giving both a greater and constant filtering efficiency and a greater possibility of collecting sedimented material prior to the periodic discharge. The two materials, fluffs and dusts, are processed separately under conditions specifically suited to the two materials, both in terms of filtering septums and in terms of speed.
The device for discharging the winding scraps according to the present invention also permits to carry out such discharging through a single duct, and moreover with a small diameter, and with low suction powers installed, since the discharging of one filter at a time is provided.

Claims

A device for collecting scraps produced by a winder constituted by a plurality of winding units (23) aligned and served by a suction system, constituted by a plurality of single aspirators (22) which individually equip each winding unit (23), wherein each single aspirator (22) alternatively supplies low depression continuous suction when the winding is in function, for the removing service of dusts and hair of the yarn, or "dust removal service", or high depression discontinuous suction for removing lengths of wire, or fluffs, derived from the recovery and joining operations of the yarn once the winding is interrupted, wherein each single aspirator (22) is provided with a pair of filters for separating the suctioned material, such filters being disposed in parallel and alternatively functioning, and of which a filter (50) is intended to retain the dusts and a filter (51) is intended to retain the fluffs, and wherein all filters (50) and (51) of the winding stations (23) forming the winder are connected through a common duct (70) to a common inertial filter (80) for collecting winding scraps that periodically discharges and receives the material retained by said filters (50) or (51), one at the time and separately for each material, and wherein the inertial filter (80) is formed by two separated and alternatively functioning filtering chambers (81,82): one chamber (81) for collecting separated fluffs through filters (51) and the other one for collecting separated dusts through filters (50), the two filtering chambers being alternatively placed in depression with an aspirator.
The device for collecting scraps produced by a winder, according to claim 1, characterized in that devices (63) for preparing some spools equipping the winder are also connected to it, in order to discharge the relative filters (65) which collect a significant quantity of residual yarn lengths.
The device for collecting scraps produced by a winder according to claim 1, characterized in that the filtering chamber (81) of the fluffs is fed through a duct (73) which directs to the chamber (81) the transport air with the transported fluffs, until it collides with the blind bottom of a wall (83), so that the fluffs loose kinetic energy and fall onto the bottom of the chamber (81), whereas the transport air discharges passing through the filtering walls (93), which are placed parallel to the flow direction and which are not directly invested by the material to be separated.
The device for collecting scraps produced by a winder according to claim 3, characterized in that the duct (73) ends with a converging nozzle (75) in order to accelerate the speed of the transport air and of the transported material.
The device for collecting scraps produced by a winder according to claim 3, characterized in that the filtering chamber (81) for the fluffs is divided into a central part (91) and into two lateral parts (92), separated by two filtering walls (93) and connected with the aspirator.
The device for collecting scraps produced by a winder according to claim 5, characterized in that the two lateral spaces (92) are linked in the upper part with an upper space (96) delimited with a net septum (93) placed on the upper part of the space (91).
The device for collecting scraps produced by a winder according to claim 1, characterized in that both the filtering chambers (81) for the fluffs and (82) for the dusts, are connected to the same aspirator (71), alternatively serving one or the other chamber, by opening and closing intercepting valves (84) and (85) placed on connecting ducts (86,87) of the two filtering chambers (81,82) to the suction side of the aspirator (71).
The device for collecting scraps produced by a winder according to claim 1, characterized in that the suction device (71) is an aspirator with a lateral channel.