TUBE SELECTION METHOD

Abstract: The individual tube (4) is positioned in a substantially central region of a support bar (2) during its continuous upward movement after withdrawing it from an accumulation region; - The presence of residual yarn on the tube is sensed by an elastically yieldable lateral lever (6) cooperating with a comb-type selector element with fine toothing in such a manner as to locate the tube in one or another axial support position; of these two positions one indicates the presence of residual yarn on the tube whereas the other indicates total absence of any residual wound yarn on the tube; - The tube with residual wound yarn is discharged by removing it from its support bar (2) by means of a fixed lateral cam (12) which interferes with the end of a tube located axially in that position which indicates the presence of even a minimum quantity of residual wound yarn.

Description: This invention relates to an apparatus for separating tubes having residual wound yarn from empty tubes for textile machines. The ever increasing automation requirements in spinning, winding and similar processes in the textile industry have produced the need for developing specific automatic control of the various operations which arise when a spinning machine is coupled to a winding machine. Specifically, this involves developing automatic methods for distributing over the winding machine the packages which arrive from the spinning machine, and for handling the empty tubes from the winding machine which have to be returned to the spinning machine. Said tubes from the winding machine can contain yarn residues. Said residues can themselves comprise a very variable number of filaments and be of very variable thickness and consistency. The problem therefore arises of identifying those tubes containing yarn residues and of discharging said residue-containing tubes into a special container provided for the purpose. Manual sorting of tubes with or without residues is known. This requires the continuous presence of one or more operators for separating the residue-containing tubes from those without residues, these latter being placed on the feed line to the spinning machine. Various apparatuses are also known for automating certain stages of this selection operation. Such apparatuses use sensors for sensing the presence of yarn on the tubes. The effectiveness of such apparatuses is only partial. Moreover, other known apparatuses are of particularly complicated construction, are bulky and are therefore costly. Examples of such apparatuses are given in GB-A-593 586 and GB-A-657 831. The concept on which these apparatuses are based is that all operations are controlled passively, the control being effected on the basis of passive operation of each member as a tube conveyor moves along. In GB-A-657 831, the selection or sorting is implemented by a device formed from a conveyor comprising bars of suitable shape for supporting tubes which have been withdrawn from an accumulation region by feed means, and for conveying them along the path taken by the conveyor. The conveyor moves upwards with an inclination sufficient to retain the tubes transversely on the conveyor. A spring-loaded lever is positioned laterally on one side of the conveyor and tends to displace the tubes in one or another axial position on the support bars as they reach the zone of action of the lever. If a tube is completely free of yarn, it is made to slide along the bars but without causing the lever to move, whereas if it is not, the yarn remains engaged by the bars, in which case the tube does not move axially, but moves the lever in the sense of spring-loading it and the tube remains in a projecting position with respect to the empty tubes. Downstream of the yieldable lever there are arranged fixed fingers at opposite positions of the conveyor such as to respectively engage the ends of the tubes with yarn and the tubes without yarn to withdraw them from the conveyor by causing them to rotate in opposite directions and then to fall separately into respective collection containers. This known device has only a limited capability of discriminating between tubes with and tubes without yarn and can operate satisfactorily in case of selection between empty tubes and tubes having a relatively high amount of yarn thereon. Tubes having only a small amount of residual wound yarn would in fact be urged axially by the yieldable lever like completely empty tubes. A device for selecting tubes having few residual yarn turns from tubes completely free of yarn is disclosed in GB-A-593 586. In this device, pivotable toothed feelers are provided on pivotal arms at the top of the conveyor, which form a complex articulated lever system including differently shaped and positioned tube discharging fingers. If residual yarn is present, the toothed feelers engage the yarn and cause displacement of the lever system to discharge the tubes to one side, whereas when no yarn is present on the tubes the toothed feelers simply slide on the tubes and do not cause any displacement of the lever system, so that the empty tubes are discharged to another side. This known device is however very complex and can perform selection only when the residual yarn turns are provided on the end regions of the tubes which come into contact with the feelers. The object of the present invention is to provide a selection device of the general type disclosed in GB-A-657 831, but capable of performing selection between tubes having small yarn residues and yarn-free tubes with simple and reliable means. This object is achieved by a device as claimed in claim 1. A preferred embodiment of the present invention is described hereinafter by way of example with reference to the accompanying drawings, in which: Figure 1A is a diagrammatic illustration of the saw-toothed selector element, on the teeth of which a tube free of yarn lies and slides; Figure 1B is a diagrammatic illustration of the saw-toothed selector element on which a tube with residual yarn lies and is engaged; Figure 2 is a diagrammatic front view of a portion of the conveyor belt provided with a tube support bar rigidly associated with the toothed selector element disposed between the belt and said bar; Figure 3 is a diagrammatic side view of the front belt portion of Figure 2 comprising the bar, and with the selector element engaging a tube present on said bar; Figure 4 is a diagrammatic illustration of that portion of the conveyor belt moving adjacent those elements which effect the positioning, sorting and selective discharge from the belt of the moving tubes; Figure 5 is a diagrammatic side view of part of the belt portion of Figure 4 at the cam which discharges those tubes with residual yarn from the belt into a collection box provided for the purpose. In the figures, identical parts or parts of identical or equivalent operation are indicated by the same reference numerals. A sorting conveyor belt 1 is provided with support bars 2 for conveying tubes 4 withdrawn from an accumulation region. The support bars 2 are connected rigidly to the conveyor belt 1 transversely thereto. The tubes 4 are supported by the bar 2 substantially centrally to the belt 1 and are driven by the belt 1 along a raising path in the direction indicated by the arrow F. 4A, 4B, 4C, 4D and 4E indicate the progressive positions which a tube 4 assumes in cooperation with the elements which effect its positioning, sorting and selective discharging from the belt 1 to feed the tube with residual yarn into a collection box 13. A comb-type saw-toothed selector element 3 with fine teeth is rigidly connected to the support bar 2 and to the conveyor belt 1 between the bar 2 and the belt 1. A fixed positioning member 5 in form of a lateral blade is shaped and positioned adjacent the belt 1 in such a manner as to cause the tube 4, withdrawn from the underlying accumulation region, to assume a precise axial selection position on its support bar 2. A lever 6 is arranged downstream of the positioning member 5 at the side of the conveyor belt 1 opposite to the member 5 and is yieldable by rotating about a pivot against the elastic action of a spring 20. The lever 6 cooperates with the selector element 3 to sort the tubes 4 driven by the belt 1, by causing them to assume one or another axial position on the support bars 2. 6A is the position which the lever 6 assumes when residual yarn is present on the tube 4 and 10A represents the position of one end of the tube 4 when residual yarn is present on the tube. Said position is such as to interfere with the profile of a fixed sloping cam 12 which is positioned in laterally facing relationship to the conveyor belt 1 downstream of the yieldable lever 6 and by means of its profile raising in the direction of movement of the conveyor belt 1 causes the tubes 4 with residual yarn to be withdrawn from the support bars 2 and to fall into and accumulate in the box 13 provided for tubes 4 with residual yarn. Under the elastic action of the spring 20, which may be a coil spring or a similar elastic element, the lever 6 adheres against a positioner 21. The operation is as follows. The tube 4 withdrawn from the accumulation region is positioned and supported on the support bar 2 during its movement, and is conveyed by the conveyor belt 1 in the direction of the arrow F. The lateral blade or cam or similar positioning element 5 urges the tube 4 axially towards a substantially central region of the bar 2 until the tube 4 is positioned in the selecting position 4A as clearly shown in Figure 4. On continuing its travel, the tube 4 interferes with the lever 6 which, urged elastically by the spring 20, tends to move it axially in the opposite direction to its previous axial movement. If the tube 4 contains residual yarn, it either does not move or moves only to a minimal extent, as the teeth of the fine toothing of the elongate saw-toothed selector element 3 project from the support bar 2 and have the major sloping flank at the side of the yieldable lever 6, so that the toothing digs into the yarn residue and locks the tube 4 axially on the longitudinal support bar 2. In this case the yieldable lever 6, which is prevented from remaining in its rest position determined by its abutment against the positioner 21, yields by compressing the spring 20 and moves into the position 6A as shown in Figure 4. As the tube 4 has not been displaced axially on the bar 2 by the lever 6, on continuing its upward translation in the direction F it reaches the position 4C, with its end in the projecting position 10A (see Figure 4). On proceeding upwards from this latter position the tube 4 interferes with the fixed cam 12 which causes it to be lifted away from the conveyor belt 1 and to be separated from its support bar and move into the position 4D (see Figure 5) from which it falls by gravity into the collection box 13 arranged in front of the raising portion of the conveyor belt 1 and the cam 12. If the tube 4 has no residual yarn, during its upward movement it interferes with the yieldable lever 6 and is displaced laterally thereby, sliding on the support bar 2 and on the upper profile of the teeth of the selector element 3, until it becomes positioned axially in the position 4B (see Figure 4). In this case the tube 4 proceeds upwards along a path different from the previously described path of the tube 4 on which yarn is present, and does not interfere with the fixed cam 12. The tube 4 therefore proceeds along the raising path of the conveyor belt 1 towards the spinning machine. A preferred embodiment of the invention has been described heretofore, but modifications can be made thereto. The shape and dimensions of the support bars 2 can be changed; the fine-toothed selector element 3 can be of a non-metallic material suitable for the purpose; the bar, saw-toothed selector element and conveyor belt can be positioned relative to each other in a different manner, without leaving the scope of the present invention as claimed hereinafter.

Claims: Apparatus for separating tubes having residual wound yarn from empty tubes for textile machines, comprising a sorting conveyor (1) movable along a raising path and having a support bar (2) for accommodating transversely and substantially centrally to the conveyor the tubes (4) withdrawn from an accumulation region, a fixed positioning member (5) adjacent to the conveyor (1) for urging the tubes (4) axially into a selection position, an elastically yieldable lever (6) arranged downstream of the positioning member (5) and adjacent to the conveyor (1) at the side thereof opposite to the positioning member (5), for engaging the tubes (4) in said selection position and selectively locating the tubes (4) in one or another axial position on said support bar (2) according to whether the tubes (4) have residual wound yarn or are empty, whereby the tubes (4) having residual wound yarn become located in a projecting position with respect to the empty tubes (4), means (12) downstream of the yieldable lever for withdrawing from the conveyor (1) the tubes (4) with residual wound yarn separately from the empty tubes (4), and a collection box (13) for the withdrawn tubes (4), characterised in that to said support bar (2) there is associated an elongate saw-toothed selector element (3) the teeth whereof project from said support bar (2) and have the major sloping flank at the side of said yieldable lever (6), in that said withdrawing means comprise a fixed sloping cam (12) extending in laterally facing relationship with the raising portion of the conveyor (1) at the side thereof at which said yieldable lever (6) is arranged, said cam (12) having a profile raising in the direction of movement of the conveyor (1) for lifting said tubes (4) with residual wound yarn away from said conveyor (1) and separating them from said support bar (2) while advancing on said raising portion of the conveyor (1), and in that said collection box (13) is arranged in front of said raising portion of the conveyor (1) and said cam (12). Apparatus as claimed in claim 1, characterised in that the saw-toothed selector element (3) is arranged between said support bar (2) and said conveyor (1).

Inventors: COLLI, LUIGI
Applicants: SAVIO S.P.A.
Application year: 1988
Main classification: B65H67
IPC codes: B65H67