WO2001055023A1

WO2001055023A1 - Synthetic-resin support or center for winding yarns into packages, with a means of automatic retention of the reserve turns of yarn

Info

Publication number: WO2001055023A1
Application number: PCT/IT2000/000302
Authority: WO
Inventors: Tiziano Romagnoli
Original assignee: Mariplast S.P.A.
Priority date: 2000-01-26
Filing date: 2000-07-19
Publication date: 2001-08-02
Also published as: ITFI20000011A0; DK176037B1; IT1314472B1; DE10085430T1; AU6468100A; TR200201853T2; ITFI20000011A1; BR0017009A; DK200201106A; MXPA02007199A

Abstract

In the channel (3) for the reserve turns is at least one circumferential slot (5) having two or more projecting protrusions (7, 9) that lead into the slot from opposite sides of the slot and are staggered with respect to each other, so that the yarn enters the slot (5) being deflected by the protrusions (7, 9), and a retaining effect is thus exerted on the yarn of the reserve turns.

Description

SYNTHETIC-RESIN SUPPORT OR CENTER FOR WINDING YARNS INTO PACKAGES, WITH A MEANS OF AUTOMATIC RETENTION OF THE RESERVE TURNS OF YARN

DESCRIPTION Supports or centers, which may be cylindrical or conical or frustoconical, on which the yarn is wound to form packages for subsequent processing (dyeing, warping, weaving or other processes) contain a region shaped into an annular channel at one end or at both ends of the support, on which to wind a number of "reserve" turns of yarn available and intended for attachment to the yarn of adjacent packages. The yarns are laid in the channel for the reserve automatically by the twisting, texturizing or packaging machines, but in many cases the yarns are wound with little tension, and are therefore unstable and easily come unwound due to handling during subsequent processing. To retain the reserve end of the yarn, therefore, it is usually secured loosely with ad hoc means that are neither very practical nor very reliable.

Italian patent no. 1 ,270,578 (and the corresponding European patent application no. 96830237.2 with priority 19.05.1995) provides a support that comprises - especially in said annular region - a lead-in incision starting at the edge and combined with a membrane portion of minimal thickness capable of being torn by the yarn as it is inserted and forced into said incision and into said portion of minimal thickness. This solution is efficient and practical, but always requires a manual intervention to attach the end of the yarn. The object of the invention is to achieve an automatic effect of retaining the yarn, as the reserve turns of yarn are being wound on, while at the same time allowing it to be unwound with ease. These and other objects and advantages will become clear in the course of the text.

In the synthetic-resin support or center for winding yarns into packages, having a channel for end reserve turns of yarn, the invention provides, in order to grip the reserve yarn, at least one circumferential slot with external lead-in profiles toward the slot, so that the yarn of the various reserve tums of yarn is repeatedly wedged in the slot to provide a retaining effect in particular on the yarn of the first turn formed.

At least two slots can be provided along the channel for the reserve yarn. A wall separated from said slot by the presence of a gap can be provided in the or in each slot. Said wall may extend from the top annular edge toward the inside of the support or center; and the top edge may form an inner seat.

In one possible embodiment, the or each slot may have two or more protrusions projecting into the slot from the opposite longitudinal sides of said slot and staggered with respect to each other, which protrusions exert a retaining effect on the yarn of the reserve turns which becomes wedged in the slot and between the protrusions. The slot in this case appears to undulate.

Each of the protrusions is of decreasing radial dimension, along its external back, from its base to its tip, such that, overall, the protrusions create a lead-in to help the yarn enter the slot.

The protrusion or protrusions extending from one side of the slot are separated at their tip or tips from the opposite side of the slot by a distance which is less than the projection of the protrusion or protrusions extending from said opposite side of the slot. In this way the yarn enters the slot with a slight alternating zig-zag deflection.

In another possible embodiment the support or center has at least one slot bounded by profiles of revolution about the axis of the support or center and of the channel for the reserve turns of yarn, so that said slot extends along a circumference. In this embodiment the upper flank of said channel of the slot or slots may be basically frustoconical, while the lower flank may advantageously form a ledge for the support or center placed coaxially on top to stand on. A slot thus defined by the lead-in flanks may have a thin inner wall, which is torn by the reserve turns of the yarn. A clearer understanding of the invention will be gained from the description and the attached drawing, the latter showing a practical, non- restrictive example of said invention. In the drawing: Fig. 1 shows a partial view of a support or center made of synthetic resin and provided with the gripping system according to the invention;

Fig. 2 shows a local section on ll-ll from Fig. 1 , much enlarged;

Fig. 3 shows a section on Ill-Ill from Fig. 1 ; Fig. 4 shows an enlarged detail from Fig. 3;

Figs 5 and 6 show an alternative embodiment in a side view and partial section and in the section on VI-VI from Fig. 5;

Fig. 7 shows a partial view of a further example of a support or center provided with the gripping system according to the invention; Fig. 8 shows the top end of the support or center from Fig. 7 in larger dimensions and partly sectioned on a radial plane;

Fig. 9 shows a side view and partial section on the broken line IX-IX from Fig. 8;

Fig. 10 shows a partial section on X-X from Fig. 9; and Fig. 11 shows another alternative embodiment.

In Figs 1 -4, the number 1 indicates the support or center made of synthetic resin, in which 3 indicates the channel for the reserve turns of yarn relating to the end illustrated. Below the flank 3A bounding the channel 3, the center is perforated with arrangements of any of the types of designs of perforations with which a center can be made. The center support 1 is of the type in which the bottom edge of a support placed on top surrounds the channel 3 and sits on the flank 3A.

In the inner wall of the channel 3, the invention provides a slot 5 which extends circumferentialiy around the channel 3 for a length which is limited but sufficient for the purposes indicated later. The channel 3 may contain a single slot 5 or may contain a number of slots 5, as shown in Fig. 3, in which three slots 5 are distributed regularly around the circumference of the channel 3.

The slot 5 or each slot 5 characteristically has a plurality of protrusions 7 and 9 which project from the longitudinal edges of the slot 5, each towards the opposite edge; in the example illustrated there are two protrusions 7 along the lower edge (when viewing Fig. 1) of the slot 5 and a single central protrusion 9 that projects from the upper edge of said slot. The protrusions 7 and 9 are staggered so that the slot 5 appears - in the presence of these protrusions 7 and 9 - basically to undulate. Each of the protrusions projects from the longitudinal edge of the slot from which it extends, and finishes at a distance from the opposite longitudinal edge which is less than the projection of the protrusion or protrusions projecting from said opposite edge. Consequently, assuming the protrusions 7 and 9 to be identical to each other, the tip of each protrusion is beyond the mid-line X-X running equidistantly between the two mutually opposing longitudinal edges of said slot 5. This accentuates the undulation of the opening defined in the slot 5 by the presence of the protrusions such as 7 and 9.

Furthermore, as can be seen in Fig. 2 in particular, the outer surface 7A and 9A of the protrusions 7 and 9 is shaped as a lead-in leading toward the inside, thereby forming a decreasing radial dimension of each protrusion from its base on the longitudinal edge of the slot 5, toward its tip. The roots of the protrusions 7 are set back from the flank 3A of the channel 3, and the root or roots of the protrusion or protrusions 9 may be flush with or similarly set back from the upper edge bounding the channel 3.

The ends 5A of the slot 5 or of each slot 5 may be slightly rounded, that is chamfered, as can be seen in Fig. 4 in particular, for reasons indicated later.

When the reserve turns of yarn are laid in the channel 3, in the section in which one or more turns are laid in the slot or each slot 5, the yarn enters between the protrusions 7 and 9, being assisted in this by the lead-in profile 7A and 9A of said protrusions 7 and 9, and ultimately passes in beyond said protrusions until positioned as indicated at F in Figs 2 and 4 in particular, after the manner of a chord of a circle, resting on the end profiles 5A of the slot 5 and perhaps slightly deflected by the protrusions such as 7 closest to the ends 5A, but certainly on the inside of said protrusions 7 and 9. With this arrangement, which can be repeated at each of the slots

5 formed in the channel 3, the turns of yarn are basically held loosely but well enough to prevent the reserve turns of yarn from failing out of the channel, and yet sufficiently slackly that one or more turns of yarn can be extracted easily from the position inside the protrusions 7 and 9 in order to allow the ends of the yarn of one package to be tied to the yarn of an adjacent package, for continuity of the uses of the yarn stored on each of the supports or centers considered.

It should be noticed that the yarn settles spontaneously, i.e. automatically, into position F without the need for any action by the operator to engage the yarn on the center, thereby achieving the object indicated at the outset. The number of protrusions must be sufficient to achieve this effect of retention, and therefore at least two opposing protrusions should be provided, or preferably at least three opposing protrusions such as those at 7 and 9 in the example shown in the drawing.

The variant shown in Figs 5 and 6 relates to a solution in which a support or center 11 has a channel 13 bounded by an upper edge 13A on which the support or center placed on top can rest, optionally with an intermediate cap or the like. In this case a slot 15, formed in the channel 13 and having protrusions 17 and 19, is not covered and closed by the bottom edge of a center placed on top; there is therefore the problem of how to close the slot 15 to prevent the passage through it of the liquid introduced under pressure into a stack of centers for the treatment of yarns in a dyeing process, for example.

To solve this difficulty, a wall 11 A is provided within the thickness of the center 11 in the or each slot 15 a short distance away from the slot and from its protrusions 17 and 19, owing to the presence of a gap 20 where the sections of reserve yarn position themselves and are held by the protrusions 17 and 19, in the same way as in the previous solution.

Figs 7-10 show a modified embodiment in which a support or center 31 comprises a channel 23 for the reserve turns of yarn at the upper end of the support or center illustrated in Fig. 7. This channel 33 begins on the upper terminal annular edge 35 of said center 31 and comprises an upper flank 33A defined by a frustoconical profile of revolution 33A which continues to the radially innermost part of the channel 33, while the lower flank 33B of said channel 33 is shaped to form a ledge 33C so that the bottom edge 37 of a center identical to the previous center, as illustrated at the bottom of Fig. 7, can be stood on the center illustrated; this bottom edge 37 is centered against the outward projection of the top edge 35 of the lower of the two centers, as sketched in in Fig. 8. In the radially innermost part of the channel 33 the reserve turns are provided with two circumferential slots 39 which are linear and not undulating (unlike the slots 15 of the previous example). These slots may be on diametrically opposite sides but may also number more than two or even be limited to just one. Each slot 39 is quite thin and extends far enough in the circumferential directional to provide a seat for the straight portion F1 of the reserve turns accommodated in the channel 33. The portions F1 of the various turns follow an approximately straight path and become stuck in the slot 39, which thus holds them in position; in particular the yarn F1 of the first turn deposited in the channel 33 is held by the yam of the other turns deposited later in the same channel. Consequently, the initial portion of the yarn accumulated as a reserve on the center is left sticking out where it can easily be grasped by the operator, yet is held sufficiently well to prevent spontaneous unwinding while allowing it to be unwound easily when the free projecting end of the yarn of the first turn is pulled. As the turns form, the yarn of the various turns is encouraged to slip into the slot 39 because of the lead- in profile which in this case is represented by the frustoconical flank 33A and by the lead-in flank 33B rising from the ledge 33C (as indicated earlier). The depth of the channel 33, compared with the position assumed by the bottom edge 37 of the upper of two centers (as shown on the left in chain lines in Fig. 8) is sufficient to accommodate an adequate number of turns for the so- called reserve yarn.

The top end of the center 31 may advantageously comprise a basically cylindrical wall 41 extending from the terminal annular edge 35 with an inward branch 41 A, leaving a useful gap 43 inside the slots 39. The portions of yarn F running along the chord of the circle, which accumulate as the various reserve turns of yarn are wound into the channel 39, can lie against the wall 41 and accumulate there. This provides an efficient retention of the initial turn of yarn which presents the end of the yarn accumulated on the center in such a way that it can be grasped. Formed between the wall 41 , 41 A and the edge 35 is a seat 45 which may be used for the positioning of a component to be placed on top of the support or center when forming a stack of supports, in equipment for the dyeing or other processing of the spools of yarn which are accumulated on supports or centers of the type in question.

In the further variant shown in Fig. 11 , the flanks 133A and 133B defining the channel 133 for the reserve turns of yarn (equivalent to the arrangement 33, 33A and 33B of the example of Figs 8-10) are so shaped as to create a slot 139 equivalent to the slot 39 but which is virtually closed by an extremely limited thickness extending between the channel 133 and the gap 143 (equivalent to the gap 43) and is such as to be torn by the yarn of the reserve turns of yarn wound into the channel 133 with sufficient tension to create the slot 139 with a flexible lip by breaking through the abovementioned thickness during the formation of the reserve of yarn. This further enhances the retention effect which the arrangement of the slots provides for the reserve turns of yarn accumulated at the top end of the center.

It should be understood that the drawing shows only an example given purely as a practical demonstration of the innovation, which can be varied in its shapes and arrangements without thereby departing from the scope of the concept on which the innovation is based. The presence of any reference numbers in the appended claims is for the purpose of facilitating the reading of the claims with reference to the description and drawing, and does not limit the scope of protection represented by the claims.

Claims

1. Synthetic-resin support or center for winding yarns into packages, having a channel (3; 13; 33) for end reserve turns of yarn, with an arrangement capable of partially gripping the reserve yarn, characterized in that it comprises at least one circumferential slot (5; 15; 39) with external lead- in profiles (7A, 9A; 33A; 33B) leading toward the slot (5; 15; 39), so that the yarn (F) of the various reserve turns of yarn is repeatedly wedged in the slot to provide a retaining effect in particular on the yarn of the first turn formed.

2. Support as claimed in the preceding claim, characterized in that it comprises at least two slots (5; 15) along the channel (3; 13) for the reserve yarn.

3. Support as claimed in claim 1 or 2, characterized in that inside the slot (15) is a wall (11 A; 41) separated from said slot by the presence of a gap (20; 43).

4. Support as claimed in claim 3, characterized in that said wall (41) extends from the top annular edge (35) toward the inside of the support or center, said top edge (35) forming an inner seat (45).

5. Support as claimed in at least claim 1 , characterized in that a slot (5; 15) has two or more protrusions (7, 9; 17, 19) projecting into the slot from the opposite longitudinal edges of said slot and staggered with respect to each other, which protrusions exert a retaining effect on the yarn of the reserve turns which becomes wedged in the slot (5; 15) and between the protrusions (7, 9; 17, 19), the slot undulating as a result.

6. Support as claimed in claim 5, characterized in that each of said protrusions (7, 9) is of decreasing radial dimension, along its external back (7A, 9A), from the longitudinal edge of the slot to its tip, such that the protrusions create a lead-in to help the yarn enter the slot.

7. Support as claimed in claim 5 or 6, characterized in that the protrusion or protrusions extending from one longitudinal edge of the slot (5) are separated at their tip or tips from the opposite longitudinal edge of the slot by a distance which is less than the projection of the protrusion or protrusions extending from said opposite longitudinal edge of the slot, so that the yarn enters the slot with an alternating zig-zag deflection.

8. Support as claimed in at least claim 1 , characterized in that a slot (39) is bounded by profiles (33A, 33B) of revolution about the axis of the support or center (31) and of the channel (33) for the reserve turns of yarn, so that said slot (39) extends along a circumference.

9. Support as claimed in claim 8, characterized in that the upper flank (33A) of said channel (33) is basically frustoconical, and in that the lower flank (33B) forms a ledge (33C) for the support placed coaxially on top to stand on.

10. Support as claimed in claim 8 or 9, characterized in that the slot (129) defined by the lead-in flanks (133A, 133B) has a thin inner wall, which is torn by the reserve turns of the yarn (F).