Device for the thermal treatment of yarns

Abstract

A device for the thermal treatment of yarns comprising at least one inlet opening and at least one outlet opening for at least one transport means, which transports the yarn through the device, and comprising separating elements at the inlet opening and the outlet opening for thermal shielding, in order to minimise the exchange of media to the environment. The separating elements are configured to have a low bending rigidity and are arranged such that a surface load is applied onto the yarn lying on the transport means, for example a conveyor belt, which is not greater than 0.005 kg*cm.sup.2.

Claims

1. Device (1) for the thermal treatment of yarns (3) comprising at least one inlet opening (4) and at least one outlet opening (5) for at least one transport means (2), which transports the yarn (3) through the device (1), and comprising separating elements at the inlet opening (4) and the outlet opening (5) for thermal shielding in order to minimise the exchange of media to the environment, in which the separating elements are arranged on the side of the transport means (2) covered with yarn (3), characterised in that the separating elements are disposed only on the side of the transport means (2) covered by the yarn and out of contact with the transport means (2) to passively follow in contact with and yield to the yarns (3), the separating elements comprise a flexible loop (7) wherein a loading element (8) is a weight arranged inside the flexible loop (7), and said separating elements having a predetermined bending rigidity to apply a predetermined surface load onto the yarn (3) lying on the transport means (2) less than 0.005 kg*cm.sup.2 selected to effectively maintain uniformity of thermal treatment of the yarn (3) within the device (1) without causing damage to the yarn (3).

2. Device (1) for the thermal treatment of yarns (3) comprising at least one inlet opening (4) and at least one outlet opening (5) for at least one transport means (2), which transports the yarn (3) through the device (1), and comprising separating elements at the inlet opening (4) and the outlet opening (5) for thermal shielding in order to minimise the exchange of media to the environment, in which the separating elements are arranged on the side of the transport means (2) covered with yarn (3), characterised in that the separating elements are disposed only on the side of the transport means (2) covered by the yarn and out of contact with the transport means (2) to passively follow in contact with and yield to the yarns (3), the separating elements comprise at least one of a flexible material (6), a flexible loop (7), a rotatable roller (10) having a surface made from a resiliently compressible material and an upper band (11) having a surface made from a resiliently compressible material, and wherein a curve is formed in the flexible material or the flexible material already has a curved form so that the separating element lies flat on a free end flat on the yarn and said separating elements (6, 7, 10, 11) having a predetermined bending rigidity to apply a predetermined surface load onto the yarn (3) lying on the transport means (2) less than 0.005 kg*cm .sup.2 selected to effectively maintain uniformity of thermal treatment of the yarn (3) within the device (1) without causing damage to the yarn (3).

3. Device according to claim 2, characterised in that a loading element (8) is arranged inside the flexible loop (7).

4. Device according to claim 2, characterised in that the yarn-contacting side of the flexible material (6) has low-friction properties.

5. Device according to claim 2, characterised in that at least two separating elements (6, 7, 10, 11) are provided respectively which are arranged behind one another.

6. Device according to claim 2, characterised in that the separating elements can be used in a multipoint installation in particular for twisting and cabling machines.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1a shows a schematic representation of a device for the thermal treatment of yarns;

(2) FIG. 1b shows an example of a yarn deposit on a transport means;

(3) FIG. 1c shows a further example of a yarn deposit on a transport means;

(4) FIG. 2 shows a schematic representation of an alternative device for the thermal treatment of yarns;

(5) FIG. 3 shows a schematic representation of alternative separating elements according to the invention;

(6) FIG. 4 shows a schematic representation of alternative separating elements according to the invention;

(7) FIG. 5 shows a schematic representation of alternative separating elements according to the invention;

(8) FIG. 6 shows a schematic representation of alternative separating elements according to the invention;

(9) FIG. 7 shows a schematic representation of alternative separating elements according to the invention;

(10) FIG. 8 shows a schematic representation of alternative separating elements according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

(11) FIG. 1a shows schematically and in a much simplified form a device 1 for the thermal treatment of yarns 3.

(12) Once the threads 3 have passed through a (not shown) shaping device and have been bent and/or crushed (crimped) three-dimensionally in a geometrically irregular manner, the thread mass lies on the transport means 2.

(13) Of course, it is also possible within the scope of this application that the threads 3 are deposited linearly or in any other form on the transport means 2. FIG. 1b shows the depositing of yarn for so-called straight set threads, i.e. threads that are referred to as uncrimped threads disregarding the bending radii. FIG. 1c shows the deposit of frieze yarns which have a three-dimensional shape.

(14) Lying on the transport means 2 the threads 3 first of all run through the inlet opening 4 and then the outlet opening 5 of the device 1 for thermal treatment which is operated by steam.

(15) The heating is performed there up to the so-called heat-setting temperature or bulk temperature. This is usually achieved in practice by saturated steam or superheated steam. In this way the threads experience a material-determined shrinking and bulking.

(16) This means that the threads 3 enter the device 1 in a deformed state and leave the device 1 in a deformed and permanently fixed state.

(17) FIG. 2 shows a device 1 for thermal treatment which is integrated into a closed system which threads enter untreated and leave in a shaped and fixed state.

(18) In addition, threads 3 are transported by an input control 12 into the closed system and supplied to a shaping device 14. Here the threads 3 are crimped and then enter the steam zone of a device 1 for thermal treatment. They are then heated to the thermosetting-temperature. Lastly, the threads 3 enter the following cooling zone 15, in which they are cooled below their material-specific glass transition temperature, so that the present state is permanently stabilised or fixed.

(19) The closed system has the particular feature that the pressure therein differs from the atmosphere. Therefore, the whole pressure chamber is sealed from the environment at the thread input and thread output by input and output controls which prevent the equalisation of pressure with the environment. However, as the three treatment areas, shaping device 14, device 1 and cooling zone 15 do not differ from one another in their pressure levels, the temperature shielding is achieved by a flexible material 6, in this case a coated fabric.

(20) FIG. 3 shows an embodiment of the flexible material 6. With a straight set yarn the straight linear structure of the deposited threads has to be fixed. Owing to its bending rigidity the film with the continuous threads 3 arches in material flow direction. Although the film lies on the threads 3 it does not compress the threads 3 essentially.

(21) FIG. 4 shows the variant in which the flexible material is in the form of a flexible loop 7 which is also weighed down by a cylinder 8.

(22) FIG. 5 illustrates the alternative of the foam-covered roller 10. As the foam is an easily compressed material, a contacting placement of the foam roller 10 does not crush the cross thread layers.

(23) FIG. 6 shows a foam-covered upper band 11 instead of the foam-covered roller 10.

(24) FIG. 7 shows an alternative embodiment of the movable flap 9. The flap 9 is mounted movably on the point of rotation 16 and can be lifted upwards to facilitate the threading of the threads by means of a pneumatic cylinder 17.

(25) FIG. 8 shows a combination of a plurality of separating elements arranged behind one another. In order to shield the device 1 from the environment, firstly two flexible materials 6 are provided, followed by a loop 7, in which an additional flexible material 6 is arranged.

(26) The present invention has been herein described in relation to an exemplary embodiment or embodiments for purposes of providing an enabling disclosure of the invention. However, it will be understood by persons skilled in the relevant art that the present invention is susceptible of a broader utility and application. Accordingly, it is to be expressly understood that the present invention is not to be construed as limited to the embodiments, features and aspects herein described, but only according to the appended claims.