TWI765886B - Device for the production of slub yarns - Google Patents

Abstract

The device (1) comprises a linear element (7) extending transversally to a yarn path, and a slide (9) for releasing the yarn (F), with a yarn sliding surface (9A) that extends from the linear element (7) and is inclined with respect to the linear element (7). The device comprises a cursor (11) movable with reciprocating motion parallel to the linear element (7) and configured so as to push the yarn (F) along the inclined surface (9A) of the yarn releasing slide (9). The linear element (7) has a longitudinal groove (8) parallel to the longitudinal extension of the linear element (7). The sliding surface (9A) of the yarn releasing slide (9) extends inside the longitudinal groove (8).

Description

Apparatus for making slub yarn

The present invention relates to the field of yarn manufacturing. More specifically, the embodiments described herein relate to improvements to apparatuses for making slub yarns.

In the textile industry, new yarns are continuously developed in order to achieve specific technical and aesthetic effects. In textile technology, it is well known to manufacture so-called "slub" fancy yarns, ie yarns in which piled areas (ie, irregularities in thickness) are provided by means of suitable roving devices or units. Roving devices are disclosed, for example, in EP0299131, US6820405, US4368612. These devices are arranged along the yarn feed path and periodically sequentially grasp the yarn briefly to modify and lengthen its path. Once the yarn path has been extended, the yarn is released to allow the yarn to build up to create a slub effect in the finished product.

In order for the yarn to be fed correctly along the path towards the winding zone, the roving device should not cause feeding irregularities, eg the roving device should not accidentally pinch the yarn. From this point of view, the prior art roving device has proven unsatisfactory.

A particularly efficient yarn roving device is disclosed in WO-A-2009/033697. The device consists of a slider or vernier fastened to an endless belt. The vernier is moved cyclically along a closed path by an endless belt having a linear acting portion extending orthogonal to the yarn feed path. The vernier is constructed to grab the yarn as it moves along the active portion of the trajectory, and is self-straightening The thread-like yarn feed path draws the yarn laterally. At the end of the linearly acting part of the closed path, a yarn deflecting member in the form of a slide is arranged. The yarn deflection member cooperates with the vernier to release the yarn from the vernier while the vernier moves past the deflecting member, so that the yarn moves backwards in its normal straight path. The deflection member has a yarn sliding surface extending away from the vernier track. The yarn may accidentally be caught or pinched between the endless belt and the deflecting member while being moved towards the yarn deflecting member under the action of the vernier. The yarn feed becomes irregular, or the yarn may break. Therefore, from the point of view of yarn feeding, this roving device proved to be unsatisfactory.

Therefore, there is still a need to improve roving devices in order to make them more functional and reliable.

In order to solve or alleviate one or more of the disadvantages of prior art roving devices, a yarn roving device is provided comprising: a thread-like element extending transversely to a yarn path; a slide for releasing the yarn or a deflection member having a yarn sliding surface extending from the thread-like element and inclined relative to the thread-like element; a vernier or slider, preferably movable parallel to the thread-like element by a reciprocating motion, and Constructed to push the yarn along the inclined surface of the yarn release slide. Advantageously, the thread-like element has a longitudinal groove parallel to the longitudinal extension of the thread-like element, and the sliding surface of the yarn release slide extends within this longitudinal groove, ie the thread release The slider penetrates into this longitudinal groove.

The yarn sliding surface is inclined relative to the thread-like element so as to form an angle with the thread-like element of greater than 90° so that the thread can travel along the thread-like sliding surface and thus be pushed along the thread-like sliding surface, until released from the cursor.

Typically, the wire-like element is a component, such as a rod, rod or rod, having a longitudinal dimension that is substantially larger than the transverse dimension. Herein, the thread-like element will also simply use the term "Rod" to indicate.

To facilitate yarn sliding, the rods may be made of ceramic materials (eg, alumina (Al ₂ O ₃ ), titania (TiO ₂ ), zirconia (ZrO ₂ )).

In other embodiments, the rod may be made of special steel with a surface treatment to increase its hardness and reduce its coefficient of friction.

Further features and embodiments of the yarn roving device according to the present invention will be described hereinafter and in the attached scope of claims which form an integral part of this specification.

1: Yarn roving device

3: Yarn guide

5: Yarn guide

7: Linear element/rod

8: Longitudinal groove

9: Yarn release slide

9X: Yarn release slide

9Y: Yarn release slide

9A: Yarn sliding surface

11: Cursor/Slider

11A: Yarn engaging member

11B: Yarn engaging member

13: Rod body

II: Line

F: Yarn

f11: double arrow

V: line

α: angle

The invention will be better understood by reading the description and accompanying drawings showing non-limiting practical embodiments of the invention. More specifically, in the drawings: Figure 1 is a front view of a yarn roving device in a possible embodiment; Figure 2 is a plan view according to line II-II of Figure 1; Figure 3 is the device of Figures 1 and 2 3A is an enlarged view of the detail indicated by A in FIG. 3; FIG. 4 is a front view of the yarn roving device in another embodiment similar to FIG. 1; Plan view on line V-V; Figure 6 is a perspective orthographic view of the device of Figures 4 and 5; Figure 6A is an enlarged view of the detail indicated by A in Figure 6.

The following detailed description of exemplary embodiments refers to the accompanying drawings. The same reference numbers in different figures identify the same or similar elements. Additionally, the drawings are not necessarily drawn to scale. Furthermore, the following detailed description does not limit the invention. Indeed, the scope of the present invention is determined by the accompanying application Definition of patent scope.

Reference throughout this specification to "one embodiment" or "one embodiment" or "some embodiments" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the disclosed subject matter . Thus, appearances of the phrases "in one embodiment" or "in an embodiment" or "in some embodiments" in various places throughout this specification are not necessarily referring to the same embodiment. Additionally, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

Referring initially to Figures 1 to 3 and 3A, a first embodiment of a yarn roving device, generally designated by the numeral 1, is described. The yarn roving device 1 may be multiple, ie the device may comprise a number of identical sections arranged in sequence in order to process parallel fed yarns. In the following, only one section of the roving device 1 will be described.

The roving device 1 comprises a pair of yarn guides 3, 5, which are substantially coaxial with each other and through which the yarn F is guided. Associated with the thread guides 3 , 5 are thread-like elements 7 in the form of rods or rods extending substantially orthogonal to the path of the yarn F bounded by the two coaxial thread guides 3 , 5 . The wire-like element 7 will hereinafter be referred to briefly as "rod 7".

The rod 7 has a longitudinal groove 8 . In the illustrated embodiment, the longitudinal groove 8 extends over the entire length of the rod 7 according to the larger dimension of the rod 7 . In other embodiments, the longitudinal groove 8 may only extend for part of the length of the rod 7, as will be apparent from the description below.

The rod 7 extends between the yarn guides 3, 5 and a slide 9 provided with an edge 9A forming a sliding surface for the yarn F, the purpose of which will be explained below. As particularly shown in the enlarged view of Fig. 3A, the slide 9 is configured such that the sliding surface 9A for the yarn F is inclined with respect to the longitudinal extension of the rod 7 so as to form an angle α with it greater than 90° (Fig. 2). also, The sliding surface 9A extends within the groove 8 . The groove 8 can have a length smaller than the longitudinal extension of the rod 7, since it is sufficient that the slider 9 can protrude in the groove, as shown in the figures.

Associated with the rod 7 is a vernier (ie, a slider) 11 , which vernier is provided with a reciprocating linear movement parallel to the longitudinal extension of the rod 7 according to the double arrow f11 . A vernier or slider 11 may be connected to an actuator member which imparts a reciprocating movement to the slider 11 . According to some embodiments, the slider 11 may eg be fastened on a rod 13 provided with a reciprocating motion according to f11 (eg controlled by an electric motor) in order to move the cursor 11 . In the case of multiple devices, the same rod body 13 can support multiple cursors 11 .

The rod body 13 may be parallel to the rod 7 .

In other embodiments, the slider or slider 11 may be connected to a flexible member such as a belt or chain, such as an endless belt or chain. The flexible member may be controlled by a motor to which reciprocating motion is applied. In yet other embodiments, the actuator member may impart continuous motion to the slider or vernier 11 along a closed trajectory. The closed trajectory may have a linear action portion and a return portion. The linear acting portion may be parallel to the rod 7 . The slider 9 and the two yarn guides 3 and 5 can be arranged at or near the end of the linear action portion of the closed trajectory along which the slider or cursor 11 moves.

In the illustrated embodiment, the vernier 11 comprises two members 11A, 11B for engaging the yarn F. One of the two yarn engaging members is arranged above the rod 7 and the other is arranged below the rod 7 .

As shown in FIGS. 1 and 2 , a single vernier 11 is associated with each pair of yarn guides 3 , 5 and with a corresponding slide 9 . In FIGS. 1-3 , the cursor 11 is shown in an intermediate position along its travel parallel to the rod 7 . In practice, the cursor 11 moves in a reciprocating motion from a first position on the left side (in the drawing) of the pair of yarn guides 3, 5 to a second position above the slider 9, as in shown in Figure 3A. The vernier 11 protrudes orthogonally to the rod 7 towards the path of the yarn F bounded by the yarn guides 3 , 5 . In this way, when the cursor 11 is moved from the first position towards the second position, the yarn F fed via the yarn guides 3 , 5 is engaged by the cursor 11 , which draws the yarn towards the slide 9 . In this way, the path of the yarn F is extended. The yarn F rests on the two yarn engaging members 11A, 11B and is pulled towards the yarn deflecting member formed by the slider 9 . During this movement, the yarn contained between the two yarn engaging members 11A and 11B can slide along the rod 7 while moving towards the slider 9 . The material from which the rod 7 is made has a low coefficient of friction (ceramic or special steel) so that the yarn can slide on the rod more easily.

When the cursor 11 reaches the vicinity of the second position ( FIG. 3A ), the section of the yarn F contained between the two yarn engaging members 11A and 11B comes into contact with the inclined surface 9A defined by the slider 9 . As the vernier 11 continues to move towards the slider 9 , the yarn F is pushed to slide along the yarn sliding surface 9A, thus moving away from the rod 7 . Due to the sliding effect, the travel of the cursor 11, the extension of the yarn sliding surface 9A and the dimensions of the two yarn engaging members 11A, 11B cause the yarn F to be released from the yarn engaging members 11A, 11B. In fact, the yarn sliding surface 9A of the slider or yarn deflector 9 extends away from the rod 7 beyond the vernier 11 so that the yarn sliding along the yarn sliding surface 9A under the action of the vernier 11 will eventually move away from the rod 7 up to beyond the range of the length of the vernier 11 protruding from the rod 7 . Once the yarn F is released from the vernier 11 , the yarn returns to the original position, delimiting the straight section between the yarn guides 3 , 5 .

The cursor 11 is then moved back to the first position so as to repeat the above operation. The two members 11A, 11B of the cursor 11 have edges inclined relative to the direction f11 so that they can move beyond the position of the yarn F when the yarn extends linearly between the yarn guides 3, 5.

By this reciprocating linear movement of the cursor 11, the yarn repeatedly goes through the yarn path and this operation produces yarn roving downstream of the roving device 1 in a known manner.

Another embodiment is described in FIGS. 4 to 6 and 6A. The same reference numerals designate the same or equivalent parts described with reference to FIGS. 1 and 3 . In FIGS. 4 to 6 , the vernier 11 or slider is symmetrical and moves between two sliders 9X, 9Y, which are symmetrical and spaced apart from each other along the extension of the rod 7 . The two thread guides 3, 5 are arranged in an intermediate position substantially equidistant from the two slides 9X, 9Y.

The cursor 11 moves from the first position corresponding to the slider 9X to the second position corresponding to the slider 9Y according to the double arrow f11 (see FIG. 6A ). On each travel, the cursor 11 grasps the yarn F tensioned between the yarn guides 3, 5 and draws the yarn F alternately towards the slide 9X and towards the slide 9Y.

In both described embodiments, the configuration of the slides 9 , 9X, 9Y with the sliding surface 9A penetrating into the groove 8 of the rod 7 prevents the yarn F from remaining pinched or otherwise between the rod 7 and the vernier 11 tangles, thus making the operation of the device 1 more regular. For this purpose, in both configurations, it is sufficient that the groove 8 extends from the area along which the slider moves towards the cursor 11 ; the groove does not necessarily need to extend over the full length of the rod 7 . In a dual configuration (ie, a configuration in which the two sliders 9X, 9Y are configured in a mirror-like fashion), the groove 8 may comprise two groove portions that are flush with the slider, while the central portion of the rod 7 may not be Has grooves. However, there may be constructional advantages to making the rod 7 with a constant cross-section and thus with a groove 8 extending over the full length of the rod 7 .

In fact, by arranging the sliding surface 9A of the slider (yarn deflector) 9 so that the sliding surface extends partially within the groove 8 of the rod 7, no tangle-free points are formed (at which points the yarn may The sliding surface of the continuous yarn that is gripped, pinched or clamped). Yarn feeding becomes smoother.

In order to create a random slub effect on the yarn, the vernier 11 can be moved in a non-periodic motion, ie it is possible to change the speed of the vernier. For this purpose, the distance between the thread guides 3, 5 can also be varied.

3: Yarn guide

7: Linear element/rod

8: Longitudinal groove

9A: Yarn sliding surface

11: Cursor/Slider

11A: Yarn engaging member

11B: Yarn engaging member

13: Rod body

F: Yarn

f11: double arrow

Claims (18)

A device (1) for roving yarn (F), comprising: a thread-like element (7) extending transversely to a yarn path; at least one yarn for releasing the yarn (F) a release slide (9; 9X; 9Y) having a yarn sliding surface (9A) extending from the thread-like element (7) and inclined relative to the thread-like element (7); a vernier (11) movable parallel to the thread-like element (7) and constructed to push the yarn (F) along the inclined surface (9A) of the yarn release slide (9; 9X; 9Y); wherein The thread-like element (7) has a longitudinal groove (8) parallel to the longitudinal extension of the thread-like element (7), and wherein the sliding surface (9A) of the yarn release slide (9) is in the Longitudinal grooves (8) extend inward such that the thread-like element (7) and the yarn sliding surface (9A) of the yarn release slide (9; 9X; 9Y) form a continuous yarn sliding surface. The device of claim 1, wherein the vernier (11) moves parallel to the linear element (7) with a reciprocating motion. The device of claim 1, wherein the vernier (11) is connected to an actuator member adapted to apply the movement to the vernier (11). The device of claim 2, wherein the vernier (11) is connected to an actuator member adapted to apply the movement to the vernier (11). The device of claim 3, wherein the actuator member comprises a rod (13) to which the vernier (11) is fastened, the rod (13) reciprocating parallel to the linear element (7) move. The device of claim 4, wherein the actuator member comprises the vernier (11) A rod body (13) to which it is fastened, the rod body (13) reciprocatingly moves parallel to the linear element (7). The device of claim 1, wherein the linear element (7) is made of ceramic material. The device according to any one of items 2 to 6 of the claimed scope, wherein the linear element (7) is made of a ceramic material. The device of claim 7, wherein the wire-like element is made of a material selected from the group consisting of: aluminum oxide (Al ₂ O ₃ ), titanium dioxide (TiO ₂ ), zirconium dioxide (ZrO ₂ ). The device of claim 8, wherein the wire-like element is made of a material selected from the group consisting of: alumina (Al ₂ O ₃ ), titania (TiO ₂ ), zirconia (ZrO ₂ ). The device of claim 1, wherein the linear element (7) is made of special steel, and the special steel has a surface treatment to increase its hardness and reduce its friction coefficient. The device according to any one of items 2 to 6 of the claimed scope, wherein the linear element (7) is made of special steel, and the special steel has a surface treatment to increase its hardness and reduce its friction coefficient. The device as claimed in claim 1, wherein the vernier (11) comprises two members (11A, 11B) for engaging the yarn (F), the two members (11A, 11B) with the longitudinal groove (8) Arranged on opposite sides of the thread-like element (7) in a way that it is arranged in an intermediate position between the two members (11A, 11B) for engaging the yarn (F). The device of any one of claims 2 to 7, 9, 11 of the claimed scope, wherein the vernier (11) comprises two members (11A, 11B for engaging the yarn (F) ), The two members (11A, 11B) are arranged on the thread in such a way that the longitudinal groove (8) is arranged in an intermediate position between the two members (11A, 11B) for engaging the yarn (F) on the opposite side of the like element (7). The device according to any one of items 1 to 7, 9, 11, and 13 of the claimed scope, wherein the longitudinal groove (8) extends over the entire length of the linear element (7). The device of any one of items 1 to 7, 9, 11, and 13 of the claimed scope, comprising two yarn release slides (9X; 9Y), the two yarns Each of the release slides (9X; 9Y) is provided with a yarn sliding surface (9A), the two yarn release slides (9X; 9Y) being arranged spaced apart from each other along the thread-like element (7) in a mirror-like position; each yarn release slide extends within the longitudinal groove (8); and the vernier (11) moves in a reciprocating motion from one of the two yarn release slides to the other . According to the device of any one of items 1 to 7, 9, 11, and 13 of the claimed scope, wherein a pair of substantially coaxial yarn guides (3, 5) are configured to define substantially is orthogonal to a yarn path of the thread-like element (7). The device of claim 16, wherein a pair of substantially coaxial yarn guides (3, 5) are configured to define a yarn path substantially orthogonal to the linear element (7), the pair of guides The yarn device (3, 5) is arranged in an intermediate position between the two yarn release slides (9X, 9Y).

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