Synthetic-resin core for winding yarn into reels with slots, for automatically retaining the turns of reserve yarn

Abstract

In the stepped cylindrical wall (3) for the reserve turns there are provided three slots (5), extending circumferentially and each having a plurality of appendages (7, 7, 9) that project with a profile leading into the slot from the opposite sides of the slot and are staggered with respect to each other, so that as the yarn F penetrates into the slot (5) it is derived in a wavy configuration by the appendages (7, 7, 9); thus an effect of retaining the reserve turns of yarn is achieved.

Description

DESCRIPTION

[0001] The present invention relates to a support or core onto which yarn is wound to form reels for use in subsequent processes (dyeing, warping, weaving or other processes), and which has an annular area at one end or at both ends of the support, for the winding of a number of turns of “reserve”, yarn which is available and intended for connection to the yarn on adjacent reels. For ensuring the positioning the turns of reserve yarn, a channel is provided to receive the reserve turns. In many cases, however, even with this arrangement, the reserve turns of yarn are rather unstable and become unwound easily, especially from the end of the reserve yarn, as a result of the handling to which the reels are subjected during the subsequent stages of processing. Arrangements are therefore made to retain the end of the reserve yarn, usually by fixing it manually in suitable notches or by other means.

[0002] In PCT/IT00/00302 in the name of the present applicant, a means is provided for creating, in the aforesaid annular channel, at least one slot extending circumferentially and having outer profiles which lead into the slot, in order to automatically engage the reserve yarn, the yarn of the various turns of the reserve yarn thus being repeatedly wedged in the slot so that a retaining effect is obtained. At least two slots are provided along the channel for the reserve yarn. A wall can also be provided within the slot or within each of the slots if necessary, this wall being spaced apart from the aforesaid slot to create a gap. Said wall can extend from the terminal annular edge toward the inside of the core, or can extend from the inside until it lies alongside and within the terminal edge. The slot or each of the slots can have a wavy profile; usually, it can have a plurality of appendages projecting into the slot from the opposing longitudinal sides of said slot and staggered with respect to each other, these appendages having the effect of retaining the yarn of the reserve turns which is wedged in the slot thus formed and which rides over said appendages.

[0003] The presence of the annular reserve channel creates a degree of difficulty in the unwinding of the reserve yarn, at the point when it is necessary to use this yarn, which can be damaged during the handling to which it is subjected at the time of extraction.

[0004] It was unexpectedly realized that, when said slots are provided, an effect of retaining the reserve yarn turns is achieved even in the absence of the annular channel; and it was also unexpectedly discovered that the reserve yarn could be recovered easily in this way without any risk of damaging it at the time of unwinding.

[0005] Therefore, the core according to the invention has, at least at one end—where turns of reserve yarn are to be formed—a cylindrical surface without an annular channel but with at least one slot extending circumferentially, in other words following the curvature of the surface, along said cylindrical surface. The slot or slots have a “wavy” configuration, into which penetrate the corresponding portions of the turns of reserve yarn which are retained therein. The extraction of the yarn is facilitated because the turns of reserve yarn are not impeded by the wall of the channel, while the retention of the turns is ensured by the “wavy” morphology of the slot or, preferably, slots.

[0006] In order to provide the wavy configuration and the retaining effect, the sides of the slot or of each slot have a plurality of appendages projecting into the slot from the opposing longitudinal sides of said slot, these appendages being staggered with respect to each other.

[0007] The appendage or appendages originating from one side of the slot have their ends spaced apart from the opposite side of the slot by a distance that is less than the projection of the appendage or appendages originating from said opposite side of the slot; thus the yarn is inserted into the slot with a moderate alternating deviation, in the form of a zigzag, which gives rise to the “waviness” of the yarn, until the yarn rides over said appendages.

[0008] A wall of cylindrical configuration can be provided within each slot, and can extend from the inside toward the terminal annular edge of the core, or from said terminal edge toward the inside. Said wall can be annular or can be limited to the area where the slots are present.

[0009] The drawing shows a non-restrictive practical embodiment of the invention. In the drawing,

[0010] FIG. 1 shows a partial terminal view of a synthetic resin core support provided with the fixing system of the “wavy” slots type according to the invention;

[0011] FIG. 2 shows a local section through II-II of FIG. 1, highly enlarged;

[0012] FIG. 3 shows a view and partial section through the broken line III-III of FIG. 1; and

[0013] FIG. 4 shows, in a similar way to FIG. 3, a modified embodiment.

[0014] In FIGS. 1 to 3, the number 1 indicates the synthetic resin core, of which the number 3 indicates a cylindrical stepped wall at the end of the core, the turns F of reserve yarn being windable onto this wall 3. Under the ridge 3A delimiting the step, the core is perforated with arrangements of any one of the types of perforation patterns with which a core can be made. The core can have its lower edge shaped in such a way that an overlying core can be fitted on and surround the wall 3 and can rest on the ridge 3A. Said lower edge can also be made in such a way that turns of reserve yarn can be wound thereon.

[0015] In the cylindrical wall 3 there is provided, according to the invention, at least one slot 5 or preferably two or more slots, each of which extends in the circumferential direction of the cylindrical wall 3 over a distance that is limited but sufficient for the purposes stated below. The wall 3 can be provided with a plurality of slots 5, as shown in FIG. 3, distributed regularly along the circumference. The slot 5, or each slot 5, characteristically has a plurality of appendages 7 and 9 that project from the longitudinal sides of the slot 5, toward the opposite side in each case; in the illustrated solution, two appendages 7 are provided along the lower side (as seen in FIG. 1) of the slot 5, and a single central appendage 9 is provided, projecting from the upper side of said slot. The appendages 7, 7 and 9 are staggered, so that the slot 5 is essentially wavy, owing to the presence of two appendages 7 and one intermediate and opposing appendage 9. Each of the appendages projects from the longitudinal side of the slot 5 from which it originates, up to a distance from the opposite longitudinal side that is less than the projection of the appendage or appendages projecting from said opposite side; therefore, if the appendages 7 and 9 are assumed to be identical to each other, the end of each appendage lies beyond the median line X-X, which is equidistant from the two opposing longitudinal sides of said slot 5; the waviness of the aperture formed in the slot 5 by the presence of appendages such as the appendages 7 and 9 is therefore accentuated. Additionally, as seen in FIG. 2 in particular, the outer surfaces 7A and 9A of the appendages 7 and 9 are shaped so that they lead inward, thus providing—in the radial direction—a decreasing radial dimension of the corresponding appendage from the base of the appendage originating along the longitudinal side of the slot 5 up to the end. The appendages 7 can originate from points lying behind the ridge 3A, and the appendage or appendages 9 can originate from points flush with or behind the wall 3. The ends 5A of the slot or of each slot 5 can be slightly rounded, as seen in particular in FIG. 3.

[0016] When the turns of the reserve yarn F are placed on the wall 3, the parts of the yarn that are placed in the slot or in each slot 5 penetrate between the appendages 7 and 9, this being facilitated by the inwardly guiding profile 7A and 9A of said appendages 7 and 9; thus the yarn F rides over said appendages toward the inside, so that it is positioned, as shown in particular in FIGS. 2 and 3, in a configuration resembling the chord of a circumference, bearing on the end profiles 5A of the slot 5 and being possibly slightly diverted by the appendages 7 closest to the ends 5A, and in all cases being located on the inner side of said appendages 7 and 9.

[0017] This configuration is repeated in all the slots 5 formed in the wall 3, and thus the turns of yarn are retained to a sufficient degree to prevent the loss of the turns of reserve yarn, but in a sufficiently limited way to allow one or more turns or all the turns of yarn to be extracted easily from the inner sides of the appendages 7 and 9, thus enabling the end of the yarn of one reel to be attached to the yarn of a contiguous reel, in order to provide continuity of use of the yarn accumulated on the reels having the core supports in question. The yarn is placed in the position F in a spontaneous way, in other words in an automatic way, without the need for intervention by the operator. The number of appendages in each slot 5 must be sufficient to provide the retaining effect; it is therefore necessary to have at least one pair of opposing appendages, or preferably at least three appendages, such as those indicated by 7 and 9 in the drawing. There may be three or four slots 5, each having a suitable length.

[0018] The slot 5 may advantageously be shielded internally to prevent the passage through it of the pressurized liquid fed into a stack of cores for yarn treatment, for example in dyeing processes. This shielding can be achieved by providing, in the thickness of the core 11, a cylindrical wall 11A extending from the edge of the core toward the inside, at the position of each slot 5 and spaced apart from the slot and from its appendages 7 and 9 to a limited extent as a result of the presence of a gap 20, in which the portions of the reserve yarn F are placed.

[0019] In the variant in FIG. 4, a cylindrical wall 111A is provided and extends from the inside to the edge, to form a gap 120 similar to the gap 20.

Claims

1. A synthetic resin core for the winding yarn into reels, with automatic retaining means for the turns of reserve yarn, characterized in that at least one of its ends, where turns of reserve yarn are to be formed, has a cylindrical surface (3) without an annular channel but with at least one slot (5) extending circumferentially along said cylindrical surface.

2. The core as claimed in claim 1, characterized in that the slot or each slot (5) has a “wavy” configuration into which the corresponding portions of the turns of reserve yarn penetrate and are retained therein.

3. The core as claimed in claim 1, characterized in that each slot (5) has a plurality of appendages (7, 9) that project into the slot from the opposite longitudinal sides of said slot (5) and are staggered with respect to each other.

4. The core as claimed in claim 1, characterized in that the appendage or appendages extending from one side of the slot (5) have their ends spaced apart from the opposite side of the slot by a certain distance that is less than the projection of the appendage or appendages extending from said opposite side of the slot, so that the turns of reserve yarn are inserted into the slot with a slightly wavy configuration, until they ride over said appendages.

5. The core as claimed in claim 1, characterized in that a wall (11A; 111A) of cylindrical configuration is present inside the slots (5), said wall possibly being annular.

6. A synthetic resin core for winding yarn into reels, with slots for automatically retaining the turns of reserve yarn; the whole as described above and as represented in the attached drawing.