YARN TENSIONING DEVICE

Abstract: A nip (18) for a yarn (11) is formed between an end of a tubular member (12) and a flattened loop section (16) of an elongate tensioning member (15). The member (12) is slidably mounted on an outlet end of a yarn tube (10) and is biased by gravity towards the section (16), thereby to exert tension on the yarn (11). The tensioning member (15) includes a further loop section (19) which acts as a guide for the yarn.

Description: Title: Yarn Tensioning Device This invention relates to a yarn tensioning device. In order to restrict the generation of lint, it is common practice to guide yarn from a storage location (e.g. a creel) to a usage point (e.g. a knitting machine) through tubing. However, in processes where the supply of yarn stops abruptly (for example in the knitting of hosiery, where yarns are striped in and out of action on high-speed machines) , problems can arise with overshoot, with an excess length of yarn being emitted from the outlet end of the tubing. This can in turn give rise to other difficulties, such as entanglement of the yarn. An attempt has been made to deal with this problem by providing a disc and a yarn guide at the outlet end of the tubing, with the excess yarn being held by the disc when required. However, this has not proved to be completely satisfactory. It is an object of the present invention to obviate or mitigate this problem. According to the present invention, there is provided a yarn tensioning device comprising a first, generally tubular member having an internal passage through which the yarn passes in use, and a second member disposed adjacent one end of the tubular member, the first and second members being capable of relative movement into and out of engagement with one another generally in the axial direction of the tubular member, the second member having therein an opening which extends to a point adjacent to said passage but which does not communicate therewith when the first and second members are mutually engaged, a nip being defined between the end of the tubular member and a part of the second member adjacent to the opening, the yarn in use passing through the opening and through the nip so as to be tensioned thereby. Preferably, at least said part of the second member is flat or flattened. Conveniently, the second member has a further opening which is displaced from the first-mentioned opening in the axial direction of the tubular member, the further opening acting as a guide for said yarn. In one particular embodiment, the second member is of generally elongate configuration, and the or each opening is formed by a loop in the member. Desirably, the second member comprises a first loop section which forms the first-mentioned opening, a second loop section which forms the further opening, the first and second loop sections lying in respective planes which are mutually parallel and perpendicular to the axis of the tubular member, and an intermediate section which interconnects the first and second loop sections and which is inclined with respect to said planes. Preferably, the first and second loop sections are disposed respectively on diametrically opposed sides of the axis of the tubular member. In an alternative embodiment, the second member is in the form of a plate, and the first-mentioned opening comprises a slot which extends from an edge of the plate. Conveniently, the further opening also comprises a slot which extends from an edge (preferably an adjacent edge) of the plate. Conveniently, the first and second members are biased into mutual engagement, for example by a spring or by gravity. Desirably, the second member is relatively fixed, and the first member is movable into and out of engagement therewith. Advantageously, the first member is slidably mounted on an outlet end of tube means through which the yarn is conveyed from a storage location towards a point of use. The present invention will now be further described, by way of example only, with reference to the accompanying drawing in which: Figure 1 is a side view (partly in section) of a first embodiment of a yarn tensioning device according to the present invention; Figure 2 is a plan view of part of the device shown in Figure l; Figure 3 is an enlarged view of another part of the device; Figure 4 is a schematic side view (partly in section) of a second embodiment of a yarn tensioning device according to the present invention; and Figure 5 is a view in the direction of arrow Y in Figure 4. Referring first to Figures 1 to 3, the yarn tensioning device shown therein is mounted at an outlet end of tube 10 through which a yarn 11 is conveyed from a storage location (such as a creel) towards a point of use (such as a knitting machine). The end of the tube 10 is oriented generally vertically, and has a generally tubular member 12 slidably mounted on its exterior. The member 12 has an internal passage 13 through which the yarn 11 passes, and is provided with a ceramic yarn guide 14 at its lower end. A tensioning member 15 in the form of a configurated length of wire (shown in detail in Figure 2) is mounted adjacent to the tubular member 12 and in fixed relation to the tube 10. The member 15 has a first loop section 16 which is flattened and which is normally engaged by the yarn guide 14. The loop section 16 forms an opening 17 which extends to a point adjacent to the passage 13, but which does not communicate therewith when the yarn guide 14 engages the loop section 16. As illustrated in Figure 3, the yarn 11 in use passes through a nip 18 formed between the yarn guide 14 and the loop section 16, and thence through the opening 17. Because the tubular member 12 is biased downwardly by gravity, the yarn guide 14 exerts pressure on the yarn 11 so that the yarn is tensioned thereby. The nip effect exerted on the yarn 11 is enhanced by the fact that the contact between the yarn guide 14 and the loop section 16 is improved by the flattened configuration of the latter. In the event that greater pressure is required for tensioning the yarn, this can be achieved by providing a spring (not shown) to act on the tubular member 12. The tensioning member 15 also includes a second loop section 19 which forms a further opening 20 and acts as a guide for the yarn 11. As can be seen to advantage in Figure 1, the loop sections 16 and 19 lie in respective planes which are mutually parallel and perpendicular to the axis of the tubular member 12, with the section 19 being displaced from the section 16 in the axial direction of the tubular member 12. The sections 16 and 19 are integrally interconnected by an intermediate section 21 which is inclined with respect to those planes. The overall configuration of the member 15 is such that the sections 16 and 19 lie on diametrically opposite sides of the axis (indicated at X in Figure 2) of the tubular member 12. In use, the yarn 11 is initially threaded through the tube 10 by a conventional blowing operation, whereafter its end portion extends downwardly from the lower end of the tubular member 12. An operative then manually grasps this end portion and leads it around the exterior of the member 15 to the point where it enters the opening 17 formed by the loop section 16. By this process, the yarn becomes located in the nip 18. Following this, the operative leads the end portion of the yarn back around the exterior of the member 15 to the point where it becomes received in the yarn guide opening 20. The yarn is then ready for use. In the event that the feed of the yarn through the device stops abruptly (such as in the knitting of hosiery where yarns are striped in and out of action on a high-speed machine), overshoot of the yarn downstream of the tensioning device is prevented by the fact that the nip 18 is provided at the very output point of the tube 10/tubular member 12. When feed of the yarn recommences, any overrun is taken up by the yarn being progressively drawn through the nip 18. In the arrangement described above, there is a comparatively small area of contact between the yarn guide 14 and the loop section 16 on the one hand, and between the yarn 11 and the loop section 16 on the other. This assists in the self-cleaning effect whereby the movement of the yarn serves to remove any lint which tends to accumulate on these parts. A modified arrangement is shown in Figures 4 and 5, wherein the tensioning member is in the form of a plate 30. In this particular instance, the plate 30 is formed by a foot portion of a generally L-shaped bracket 31 which is fixedly mounted on the end of the tube 10 by way of clips 32. As can be seen to advantage in Figure 5, the foot portion 30 has a slot 33 extending inwardly from an edge 34 thereof. The slot 33 extends towards the axis X of the tubular member 12, but terminates short of the internal passage 13 so that, when member 12 is engaged with foot portion 30, the slot 33 does not communicate with the passage 13. In this way, a nip 35 is defined between the end of the member 12 and the confronting surface of the foot portion 30, and in use the yarn 11 passes through this nip. The member 12 is biased into engagement with the foot portion 30 by gravity, and this action serves to apply a pressure at the nip 35 which prevents overshoot of the yarn 11 in the event that the supply of yarn is stopped abruptly. In the event that greater pressure is required for this purpose, a spring (not shown) can be positioned between the member 12 and the lower one of the clips 32. During initial threading, the yarn 11 is blown through the tube from the end adjacent to where the yarn is stored. To facilitate this process, the foot portion 30 is provided with a further slot 36 which extends from an adjacent edge 37 thereof and which does communicate with the internal passage 13. The initial feeding of the yarn through the tube 10 causes the yarn to extend through the slot 36. From this position, the yarn can be removed from the slot 36, moved around the edges 37 and 34 of the foot portion 30, and then engaged with slot 33. To facilitate this engagement, the slot 33 is provided with a lead-in portion 38.

Claims: CLAIMS A yarn tensioning device comprising a first, generally tubular member (12) having an internal passage (13) through which the yarn (11) passes in use, and a second member (15) disposed adjacent one end of the tubular member (12), the first and second members being capable of relative movement into and out of engagement with one another generally in the axial direction of the tubular member (12) , the second member (15) having therein an opening (17) which extends to a point adjacent to said passage (13) but which does not communicate therewith when the first and second members are mutually engaged, a nip (18) being defined between the end of the tubular member (12) and a part (16) of the second member (15) adjacent to the opening, the yarn (11) in use passing through the opening (17) and through the nip (18) so as to be tensioned thereby. A yarn tensioning device as claimed in claim 1, wherein at least said part (16) of the second member (15) is flat or flattened. A yarn tensioning device as claimed in claim 1 or 2, wherein the second member (15) has a further opening (20) which is displaced from the first-mentioned opening (17) in the axial direction of the tubular member (12) , the further opening (20) acting as a guide for said yarn (11). A yarn tensioning device as claimed in claim 1, 2 or 3, wherein the second member (15) is of generally elongate configuration, and the or each opening (17, 20) is formed by a loop (16, 19) in the member (15). A yarn tensioning device as claimed in claim 4, wherein the second member (15) comprises a first loop section (16) which forms the first-mentioned opening (17), a second loop section (19) which forms the further opening (20), the first and second loop sections (16, 19) lying in respective planes which are mutually parallel and perpendicular to the axis (X) of the tubular member (12), and an intermediate section (21) which interconnects the first and second loop sections (16, 19) and which is inclined with respect to said planes. A yarn tensioning device as claimed in claim 5, wherein the first and second loop sections (16, 19) are disposed respectively on diametrically opposite sides of the axis (X) of the tubular member (12). A yarn tensioning device as claimed in claim 1 or 2, wherein the second member is in the form of a plate (30), and the first-mentioned opening comprises a slot (33) which extends from an edge (34) of the plate (30). A yarn tensioning device as claimed in claim 7, wherein the further opening also comprises a slot (36) which extends from an edge (37) of the plate (30). A yarn tensioning device as claimed in claim 8, wherein the slots (33, 36) extend from adjacent edges (34, 37) of the plate (30). A yarn tensioning device as claimed in any preceding claim, wherein the first and second members (12, 15) are biased into mutual engagement. A yarn tensioning device as claimed in any preceding claim, wherein the second member (15) is relatively fixed and the first member (12) is movable into and out of engagement therewith. A yarn tensioning device as claimed in any preceding claim, wherein the first member (12) is slidably mounted on an outlet end of tube means (10) through which the yarn (11) is conveyed from a storage location towards a point of use.

Inventors: SHELTON MARK ALAN, SHELTON WILLIAM EWART ALAN, SHELTON, MARK, ALAN, SHELTON, WILLIAM, EWART, ALAN
Applicants: SHELTON ALAN LTD, SHELTON MARK ALAN, SHELTON WILLIAM EWART ALAN, ALAN SHELTON LIMITED, SHELTON, MARK, ALAN, SHELTON, WILLIAM, EWART, ALAN
Application year: 1995
Main classification: B65H59
IPC codes: B65H59