Apparatus for the formation of yarn in a chenille machine

Abstract: Apparatus for driving interweaving threads in a yarn-forming unit of a chenille machine comprising, for each of the two sides of a gauge (1) on which the fuzzy thread is wound and sized, a pair of rollers (3, 30) forming a calender for driving two interweaving threads to be twisted in order to engage the lengths of the fuzzy thread. Of said rollers (3, 30), the upper one (3) of at least one of said two pairs is provided with a plurality of radial channels (31) associated to air-suction means to pull in the lengths of fuzzy threads being cut by a blade (2) towards the respective edge, at least over an arc thereof instantaneously facing the gauge (1) during the rotation of the rollers (3, 30) of said pair.

Description: The present invention refers to an apparatus for the formation of yarn in a chenille machine such as known from e.g. EP-A-0 717 134. A yarn chenille is known to be made up of two suitably twisted interweaving threads intended to engage lengths of a fuzzy thread. To this purpose, the chanille machines comprise at least a yarn-forming unit in which a gauge is provided for winding up and sizing the fuzzy thread, a circular blade for cutting said fuzzy thread into lengths of predetermined extension, means for moving forward the threads together with the lenghts of fuzzy thread by a pair of rollers or wheels forming, on both sides of the gauge, a calender member for driving the interweaving threads, and means for twisting the interweaving threads with the lengths of fuzzy threads interposed therebetween. The yarn thus produced takes up a typical, substantially cylindrical configuration with a central core consisting of twisted interweaving threads and from which the free ends of the lengths of fuzzy thread are made to protrude. One of the problems mostly felt also in this industrial field is how to increase the production in a simple and cost-effective way without impairing the quality of the finished product. The main object of the present invention is to overcome the above problem. A further object of the present invention is that of improving the quality of the finished product. This result has been achieved, according to the invention, by providing an apparatus having the features indicated in the characterizing part of claim 1. Further characteristics being set forth in the dependent claims. The advantages deriving from the present invention lie essentially in that it is possible to increase the production as well as the quality of the chenille yarn in a simmple and cost-effective way without major interventions for structural changes in the chenille-forming machines already in existence; that it is possible to simplify the guide of at least part of the interweaving threads as well as the conformation of the gauge, the latter exhibiting a slit in the conventional systems to guide the interweaving threads which rest onto the lower rollers of the driving calenders disposed by the sides of the gauge, by fully eliminating the need of providing said slit in the body of the gauge and thus lowering both cost and time for the manufacturing thereof; that an apparatus according to the invention is simple to make, cost-effective and reliable even also a prolonged service life. These and other advantages and characteristics of the invention will be best understood by anyone skilled in the art from a reading of the following description in conjunction with the attached drawings given as a practical exemplification of the invention, but not to be considered in a limitative sense, wherein: Fig. 1A shows a front view of an apparatus according to the invention in a yarn-forming unit for chenille machines; Fig. 1B shows a side view of the unit with the apparatus of Fig. 1A; Fig. 2A shows the front view, partially in section, of the upper roller of the apparatus according to the invention; Fig. 2B shows a view, partially in section, of means for the suction and ejection of air through the radial channels of the roller of Fig. 2A. Reduced to its basic structure, and reference being made to the figures of the attached drawings, an apparatus for driving interweaving threads in a yarn-forming unit of a chenille machine according to the invention comprises, for each of the two sides of the gauge (1) on which the fuzzy thread - to be cut into lenghts of predetermined extension by a circular blade (2) located in front of the gauge (1) - is wound and sized, a pair of rollers (3, 30) disposed at a short and preset distance from the gauge (1) and forming a calender which drives into motion the two threads to be twisted in order to engage said lengths of fuzzy thread, the axis of rotation of said rollers (3, 30) being parallel to each other and to the plane of the blade (2), so that the respective edges on which the very draw takes place will result orthogonal to the gauge (1). Of said rollers (3, 30), the upper one (3) of at least one of said two pairs is provided with a plurality of radial channels (31) associated to air-suction means to pull in the lengths of fuzzy threads being cut by the blade (2) towards the respective edge at least over an arc thereof instantaneously facing the gauge (1) during the rotation of the rollers (3, 30) of said pair. Guided on the edge of the first roller (3) is a corresponding interweaving thread which is directed towards the edge of the second roller (30) together with the lengths of the fuzzy thread being removed from the surface of the gauge (1) by means of the said suction. Also guided on the edge of the second roller (30) is the second interweaving thread and, owing to the twisting of the two interweaving threads with the lengths of fuzzy thread interposed therebetween, the chenille yarn is produced. The twisting of the two interweaving threads is operated in a conventional way, that is, by winding up the threads on a spindle driven into rotation at a preset speed by a driving member. The transfer of the lengths of fuzzy thread from the gauge (1) to the roller (30), in the manner described above, is particularly effective, also under heavy operating conditions, contrary to the case of conventional systems which not always ensure the proper transfer of the lengths of fuzzy thread from the gauge to the draw rollers. Since the removal of the lengths of fuzzy thread is operated directly by the roller (3), there is no need for passing the interweaving threads through the body of the gauge, contrary to the case of conventional systems. Advantageously, in order to improve the suction effect over the active edge of the roller (3), a side surface thereof is provided with holes (32) which in the whole make up an air intake of suitable dimensions. Advantageously, according to the invention, the above channels (31) of the roller (3) are further associated to air ejection means to obtain the ejection of the lengths of fuzzy thread possibly retained inside the channels (31), that is, those not engaged by the interweaving threads, so that the channels (31) will result always free to allow for the intervention of the suction means (4). Moreover, advantageously, the body of said roller (3) is housed in a cap (33) to which the air suction and ejection means are connected by means of corresponding fixed conduits (4, 5). Suitably provided rearwardly of the roller (3) is a distributor (6) with a plurality of slots (60) to which the conduits (4, 5) communicating with the channels (31) are connected. The advantages derived from the use of the above described apparatus are obtainable, though to a less appreciable extent, also in the case in which only one of the rollers (3) sideway of the gauge (1) is shaped as indicated above. Figs. 1A and 1B of the accompanying drawings show the head (7) for winding up the fuzzy thread over the gauge (1) and the movable arms (8) for supporting the rollers (3, 30). The said arms (8) are connected to the machine frame (9) and associated to springs (80) for bringing the rollers (3, 30) back to the gauge (1).

Claims: Apparatus for driving interweaving threads in a yarn-forming unit of a chenille machine according to the invention comprises, for each of the two sides of the gauge (1) on which the fuzzy thread - to be cut into lenghts of predetermined extension by a circular blade (2) located in front of the gauge (1) - is wound and sized, a pair of rollers (3, 30) disposed at a short and preset distance from the gauge (1) and forming a calender which drives into motion the two threads to be twisted in order to engage said lengths of fuzzy thread, the axis of rotation of said rollers (3, 30) being parallel to each other and to the plane of the blade (2), so that the respective edges on which the very draw takes place will result orthogonal to the gauge (1), characterized in that the upper (3) of at least one of said two pairs of rollers (3, 30) is provided with a plurality of radial channels (31) associated to air-suction means to pull in the lengths of fuzzy threads being cut by the blade (2) towards the respective edge, at least over an arc thereof instantaneously facing the gauge (1) during the rotation of the rollers (3, 30) of said pair. Apparatus according to claim 1, characterized in that one side surface of said roller (3) is provided with holes (32) which in the whole make up an air intake of suitable dimensions. Apparatus according to claim 1, characterized in that the above channels (31) of roller (3) are further associated to air ejection means to obtain the ejection of the lengths of fuzzy thread possibly retained inside the channels (31), that is, those not engaged by the interweaving threads, so that the channels (31) will result always free to allow for the intervention of the suction means (4). Apparatus according to one or more of the preceding claims, characterized in that the body of said roller (3) is housed in a cap (33) to which the air suction and ejection means are connected by means of corresponding fixed conduits (4, 5). Apparatus according to one or more of the preceding claims, characterized in that a distributor (6) is provided located rearwardly of the roller (3) and having a plurality of slots (60) to which the conduits (4, 5) communicating with the channels (31) are connected.

Inventors: SOSTEGNI GIULIANO, SOSTEGNI, GIULIANO
Applicants: GIESSE SRL, GIESSE S.R.L.
Application year: 1998
Main classification: D02G3
IPC codes: D02G3