A method for processing a strand-type fiber bundle includes sending the fiber bundle to an air nozzle of a pre-spinning machine used to produce roving. During normal operation, a twist is imparted to the fiber bundle via a vortex air current within the air nozzle to form the roving, wherein the roving leaves the air nozzle through an outlet and is deposited in or on a receptacle. Normal operation of the pre-spinning machine is interrupted in a stop phases during which roving is not produced by the air nozzle. A start-up phase is commenced between the stop phase and subsequent normal operation wherein the roving produced during the stop phase is discarded via a roving discharge after leaving the air nozzle when quality of the roving does not meet a desired specification. The roving discharge is deactivated when the quality of the roving meets the desired specification and the roving removed by the roving discharge is separated from the roving.

A method for processing a strand-type fiber bundle includes sending the fiber bundle to an air nozzle of a pre-spinning machine used to produce roving. During normal operation, a twist is imparted to the fiber bundle via a vortex air current within the air nozzle to form the roving, wherein the roving leaves the air nozzle through an outlet and is deposited in or on a receptacle. Normal operation of the pre-spinning machine is interrupted in a stop phases during which roving is not produced by the air nozzle. A start-up phase is commenced between the stop phase and subsequent normal operation wherein the roving produced during the stop phase is discarded via a roving discharge after leaving the air nozzle when quality of the roving does not meet a desired specification. The roving discharge is deactivated when the quality of the roving meets the desired specification and the roving removed by the roving discharge is separated from the roving.

An air spinning method comprising the steps of: preparing at least one web of textile fibers (N1), to be fed by at least one introducer element (24) upstream of an air spinning device (28), drawing said at least one web (N1) with at least one drawing device (32), feeding said web (N1), previously drawn, in a spinning chamber (36) of the air spinning device (28), spinning the fibers (12) inside the spinning chamber (36) by means of compressed air jets, so as to: obtaining a yarn (4) comprising internal fibers (20) surrounded by external fibers (16), wherein the yarn (4) has an overall thread count lower than Ne20 and wherein the total number of internal (20) and external (16) fibers is less than 200.

An air-jet type spinning device (4), comprising an at least partially hollow body (8) which delimits a cylindrical spinning chamber (12), the body comprising at least one injection hole (16) configured to introduce a flow of compressed air in said spinning chamber (12), a fibre feeding device (20), facing said spinning chamber (12) so as to feed the fibres in the spinning chamber (12). The fibre feeding device (20) comprises a fibre feeding channel (24) having a first straight section (28) leading, at a shoulder (32), into a pre-chamber (36) facing and communicating with said spinning chamber (12). The spinning device comprises a spinning spindle (48) at least partially inserted in the spinning chamber (12) and fitted with a spinning channel (52) for the transit of yarn obtained from said fibres, the spinning channel (52) having a main axis which defines a spinning direction (X-X), and having a front input (56) for the introduction of the yarn in said spinning channel (52). Advantageously, a diameter (60) of the spinning chamber (12), measured relative to a cross-section plane perpendicular to said main axis, is between 5.6 and 7.4 mm. [FIG. 2]

The present invention provides a polyamide (preferably Nylon 66) yarn for weaving or knitting clothes articles which have a cooling effect on the skin of the wearer. The yarn contains an inorganic additive (preferably Titanium dioxide) in an amount of between 0.3 and 3.0 wt % and is characterized by a low crimp modulus and a flat cross section.

The present invention provides a polyamide (preferably Nylon 66) yarn for weaving or knitting clothes articles which have a cooling effect on the skin of the wearer. The yarn contains an inorganic additive (preferably Titanium dioxide) in an amount of between 0.3 and 3.0 wt % and is characterized by a low crimp modulus and a flat cross section.

An air-jet type spinning device (4), comprising a body (8) at least partially hollow which defines a spinning chamber (12), a fibre feed device (16), facing said spinning chamber (12) so as to feed the fibres into the spinning chamber (12), a spinning spindle (20) at least partially inserted in the spinning chamber (12) and fitted with a spinning channel (24) for the suction of yarn obtained from said fibres, the spinning channel (24) defining a spinning direction (X-X), at least one channel (28) for sending a jet of compressed air inside the spinning chamber (12). Advantageously, the spinning chamber (12) is delimited at least partially by an outer side wall (32), opposite the spinning spindle (20), wherein at least one thread (36) is made on said outer side wall (32), wherein said at least one channel (28) is oriented so as to direct the jet of compressed air towards the at least one thread (36) in order to be guided and oriented by the latter.

An air-jet type spinning device (4), comprising a body (8) at least partially hollow which defines a spinning chamber (12), a fibre feed device (16), facing said spinning chamber (12) so as to feed the fibres into the spinning chamber (12), a spinning spindle (20) at least partially inserted in the spinning chamber (12) and fitted with a spinning channel (24) for the suction of yarn obtained from said fibres, the spinning channel (24) defining a spinning direction (X-X), at least one channel (28) for sending a jet of compressed air inside the spinning chamber (12). Advantageously, the spinning chamber (12) is delimited at least partially by an outer side wall (32), opposite the spinning spindle (20), wherein at least one thread (36) is made on said outer side wall (32), wherein said at least one channel (28) is oriented so as to direct the jet of compressed air towards the at least one thread (36) in order to be guided and oriented by the latter.

TA multifunctional nozzle for a spinning machine used to produce at least real-twist yarn. The multifunctional nozzle comprises a nozzle channel open on one side in a nozzle housing and in which a vortex flow can be generated. A nozzle body which is shorter than the nozzle channel is provided with a through-channel for the passage of a thread or fibre band. An annular gap with a narrow point is formed within the nozzle channel. The annular gap tapering on both sides at the narrow point. The narrow point is arranged downstream of a fluid inlet which leads to the nozzle channel. A hollow body-type flow conducting body is provided between the annular gap and the open end of the nozzle channel for guiding the thread or fibre band together with a fluid, the annular gap being formed between the nozzle body and the nozzle housing and/or the flow conducting body.

TA multifunctional nozzle for a spinning machine used to produce at least real-twist yarn. The multifunctional nozzle comprises a nozzle channel open on one side in a nozzle housing and in which a vortex flow can be generated. A nozzle body which is shorter than the nozzle channel is provided with a through-channel for the passage of a thread or fibre band. An annular gap with a narrow point is formed within the nozzle channel. The annular gap tapering on both sides at the narrow point. The narrow point is arranged downstream of a fluid inlet which leads to the nozzle channel. A hollow body-type flow conducting body is provided between the annular gap and the open end of the nozzle channel for guiding the thread or fibre band together with a fluid, the annular gap being formed between the nozzle body and the nozzle housing and/or the flow conducting body.