Apparatus for guiding, conveying or treating a fiber cable

Abstract

An apparatus for guiding, conveying or treating a fiber cable 7, comprising several driven rollers 2, 3, 4.1, 4.2, the fiber cable being guided along the circumference of the rollers so as to partly wrap therearound. The rollers include a roller 2 for feeding the fiber cable and a roller 3 for discharging the fiber cable. The remaining rollers 4.1, 4.2, 4.3, 4.4 are disposed relative to the feeding roller and the discharging roller in such a way that the fiber cable can be guided on the rollers at a respective angle of contact of >180°. In order to involve all rollers to the same extent, the feeding roller and the inlet of the fiber cable, as well as the discharging roller and the outlet of the fiber cable, are arranged relative to each other such that the fiber cable can be guided along the circumference of the feeding roller and along the circumference of the discharging roller so as to partly wrap therearound at a respective angle of contact of >180°.

Description

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation of international application PCT/EP2004/010117, filed 10 Sep., 2004, and which designates the U.S. The disclosure of the referenced application is incorporated herein by reference.

BACKGROUND OF THE INVENTION

The invention relates to a apparatus for guiding, conveying or treating a fiber cable of the type which includes a plurality of driven rollers.

In the production of synthetic fibers, it is known that the individual spun fiber bundles are merged together into a fiber cable and are drawn from the spinneret using a apparatus comprising several driven rollers. Sufficient fiber tractive force must be generated by the rollers in order to draw all the fiber strands forming the fiber cable evenly from the spinneret. In order for a defined spinning denier to be set when guiding the fiber cable, there must be no occurrence of any slip between the fiber cable and the rollers, especially in the outlet region. All the rollers can thereby be driven at an equal circumferential speed or at a differential speed for the purpose of imparting a draw.

For the build-up of the tractive forces as well as for preventing any slip, the fiber cable must be guided on the rollers at certain minimum angles of contact. The sum of all the angles of contact on the rollers functions as the measure for the maximum producible tractive force. Six, eight or even more rollers are thus used for drawing the fiber cables. Such a apparatus is known, for example, from DE 24 55 117 A1. This known apparatus has a feeding roller for feeding the fiber cable and a discharging roller for discharging the fiber cable. Between the feeding roller and the discharging roller, altogether five additional rollers are arranged offset relative to one another in such a way that the fiber cable can be guided on the rollers arranged in-between at the largest angles of contact possible.

The problem occurring in case of such a plurality of rollers, however, is that the physical coherences (Eytelwein's rope friction formula) lead to a variable load of the rollers. Additional fluctuations in the coefficients of friction between the individual pairings of the fiber cable and the rollers due to, for example, inequalities in the preparation and/or in the preparation order of the fiber cable, reinforce such inequalities.

It is therefore an object of the invention to further improve a apparatus of the abovementioned type for guiding, conveying or treating a fiber cable in such a way that the previously mentioned disadvantages do not occur.

Another object of the invention is to create a generic apparatus wherein the largest possible tractive forces can be generated using relatively few rollers for guiding the fiber cable.

SUMMARY OF THE INVENTION

The above and other objects and advantages of the invention are achieved by arranging the feeding roller and the inlet of the fiber cable, as well as the discharging roller and the outlet of the fiber cable, relative to one another in such a way that the fiber cable can be guided along the circumferences of the feeding roller and the discharging roller so as to partly wrap therearound at an angle of contact of >180°.

Preferred embodiments of the invention are defined by the features and the combinations of features as further described below.

The invention is based on the recognition that according to Eytelwein's correlation, the rollers, especially in the outlet region are lightly loaded if the requirement of uniform circumferential speeds is met. The apparatus according to the invention prevents this by guiding the fiber cable even on the discharging roller so as to wrap therearound to the maximum extent possible. A required total wrap is thus achieved using fewer rollers and secondly due to the larger angle of contact, the discharging roller can be used and loaded for building up the tractive forces.

The invention further provides for the feeding roller and the inlet of the fiber cable to be arranged so as to achieve a large angle of contact of >180°. Each of the rollers can thus be used to a high utilization degree so that it is possible to generate relatively large total wraps using few rollers and thus relatively large tractive forces for drawing or stretching the fiber cable.

This effect can be further improved in that the fiber cable can be guided on all the rollers so as to partly wrap therearound at a respective angle of contact of >190°, preferably of >200°.

In doing so the rollers can be arranged in such a way that the fiber cable is guided on each of the rollers at a substantially equal angle of contact.

However, it is also possible to configure the angles of contact on the feeding roller and the discharging roller variably in proportion to the angles of contact on the remaining rollers.

In an advantageous arrangement of altogether four rollers, the additional rollers can be arranged between the feeding roller and the discharging roller so that the fiber cable can be guided with even transitions between the rollers.

However, it is also possible to arrange the feeding roller and the discharging roller between the additional rollers. The result is a longer free guiding passage for the fiber cable between the additional outboard rollers. Using a corresponding selection of the angles of contact, total wraps of >900° can be achieved even when using four rollers.

In order to be able to create larger total wraps of >1,000° and also larger draw forces or stretch forces, three or more than three rollers can advantageously be arranged between the feeding roller and the discharging roller.

In cases in which differential speeds between the individual rollers are required, the drive motors of the rollers are controlled advantageously using individual converters in each case. In case the circumferential speed of the rollers is equal, each of the drive motors can be controlled using a common group converter. A mechanical coupling of the rollers in connection with a drive motor is also possible.

The apparatus according to the invention is thus suitable especially for drawing and stretching fiber cables using the least possible number of rollers. Simple handling is thus achieved, in that there are fewer fiber transfers between the individual rollers. Economizing on every additional fiber transfer simultaneously involves a reduction in the risk of roll formation. The apparatus according to the invention thus represents a cost effective technical solution for guiding, conveying and treating a fiber cable.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments of the apparatus according to the invention are described in more detail in the following description, with reference to the enclosed drawings, of which:

FIG. 1 schematically illustrates the top view of a first embodiment of the apparatus according to the invention;

FIG. 2 illustrates a side view of the first embodiment;

FIG. 3 schematically illustrates a second embodiment of the apparatus according to the invention, said embodiment comprising four rollers;

FIG. 4 schematically illustrates a third embodiment comprising four rollers;

FIG. 5 schematically illustrates a fourth embodiment comprising four rollers;

FIG. 6 schematically illustrates another embodiment of the apparatus according to the invention, said embodiment comprising five rollers;

FIG. 7 schematically illustrates an embodiment of the apparatus according to the invention, said embodiment comprising six rollers; and

FIG. 8 schematically illustrates another embodiment comprising six rollers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1 and 2 schematically illustrate a first embodiment of the apparatus according to the invention. FIG. 1 illustrates a top view of the embodiment without the guiding of a fiber cable and FIG. 2 illustrates the side-view of the embodiment with the guiding of a fiber cable. The following description applies to both the figures unless explicit reference is made to either of the figures.

A feeding roller 2, a discharging roller 3 and additional rollers 4.1 and 4.2 are arranged next to one another on a support wall 1. The rollers 2, 3, 4.1 and 4.2 are designed identically and are held rotatably with one drive end on the support wall 1. The drive ends of rollers 2, 3, 4.1 and 4.2 are each coupled to a drive motor 8. A converter 9 is assigned to each of the drive motors 8, each of which drive motors 8 can be controlled using the converter.

The arrangement of the feeding roller 2, the discharging roller 3 and the rollers 4.1 and 4.2 is selected in such a way that the each of the outboard rollers 4.1 and 4.2 is held at a large distance from one another on the support wall 1. The rollers 4.1 and 4.2 are located in a horizontal plane opposite to and at a distance from one another.

Between the rollers 4.1 and 4.2, the feeding roller 2 and the discharging roller 3 are arranged at a short distance from one another in a second horizontal plane. The second horizontal plane is positioned below the first horizontal plane, in which the rollers 4.1 and 4.2 are arranged. The distance between the two horizontal planes is selected in such a way that a fiber cable 7 fed horizontally using an inlet 5 can be supplied freely from outside to the feeding roller 2 without any contact with the upstream roller 4.1. The fiber cable 7 can thus be guided away accordingly using an outlet 6 by the discharging roller 3 horizontally without any contact with the downstream roller 4.2. What is achieved by the symmetrical arrangement of the rollers 2 and 3, and also 4.1 and 4.2 is that each fiber cable 7 can be guided on the rollers 2, 3, 4.1 and 4.2 at the same angle of contact α. The thus attainable angle of contact α could have a value of, for example, 227.5° so as to achieve a total wrap of 910°. The fiber transition from the feeding roller 2 to the roller 4.1 and also the fiber transfer from the roller 4.2 to the discharging roller 3 are configured identically for this purpose.

The embodiment illustrated in FIGS. 1 and 2 of the apparatus according to the invention could be used for guiding and conveying a fiber cable, all the rollers in said embodiment being driven at equal circumferential speed. In such a case, the drive motors 8 of the rollers 2, 3, 4.1 and 4.2 are controlled collectively by a group converter 10, as illustrated in FIG. 1 by the dashed lines.

FIGS. 3, 4 and 5 schematically illustrate additional embodiments of the apparatus according to the invention, each of said embodiments comprising four rollers. FIGS. 3, 4 and 5 each illustrate the side-view of each of the different arrangements of the rollers, wherein the additional rollers 4.1 and 4.2 are each arranged between the feeding roller 2 and the discharging roller 3. The design of the apparatus being substantially identical to the preceding example, reference is made to the description of FIGS. 1 and 2. Only the differences are explained below in more detail.

In FIG. 3, the feeding roller 2 and the discharging roller 3 are arranged in a vertical plane on top of one another. The two additional rollers 4.1 and 4.2 are arranged in a horizontal plane centrally between the feeding roller 2 and the discharging roller 3. The distances between the rollers are configured in such a way that a fiber cable 7 is guided along the circumference of the rollers 2, 4.1, 4.2 and 3 so as to partly wrap around each roller. The fiber cable 7 is guided on the feeding roller 2 and the discharging roller 3 at an angle of contact α. In contrast, a slightly larger contact angle β is attained in case of the additional rollers 4.1 and 4.2. The angle of contact α on the feeding roller 2 and on the discharging roller 3 is configured to be >200°. For this purpose the inlet 5 of the fiber cable 7 is embodied diagonally above the feeding roller 2. Accordingly, the outlet 6 of the fiber cable 7 is embodied diagonally below the discharging roller 3.

FIG. 4 illustrates another possible arrangement of the four rollers. Here, the feeding roller 2 and the roller 4.2 are arranged in a first vertical plane on top of one another with a distance in-between and the roller 4.1 and the discharging roller 3 are arranged in a second vertical plane on top of one another with a distance in-between. The rollers 2, 4.1, 4.2 and 3 are arranged offset relative to one another in the two vertical planes lying next to one another. The inlet 5 and the outlet 6 of the fiber cable 7 are identical to the preceding embodiment illustrated in FIG. 3. Here too, the fiber cable 7 is guided on the feeding roller 2 and on the discharging roller 3 at an angle of contact α. The fiber cable 7 is guided on the additional rollers 4.1 and 4.2 at an angle of contact β. The angle of contact β is marginally larger than the angle of contact α. An angle of contact α of >200° can be advantageously achieved due to the diagonal arrangement of the inlet 5 and the outlet 6.

FIG. 5 illustrates an arrangement of the four rollers, wherein an angle of contact α200° is also attained on the feeding roller 2 and the discharging roller 3. However, here the fiber cable 7 is fed horizontally using the inlet 5 and is discharged horizontally using the outlet 6. The rollers 2, 4.1, 4.2 and 3 are held in an offset arrangement on top of one another. A larger angle of contact β is attained on each of the additional rollers 4.1 and 4.2.

The arrangements of the rollers illustrated in the FIGS. 3 to 5 enable the attainment of individual angles of contact of up to a maximum of 230°. An increase and/or the order of magnitude of the angles of contact is substantially limited by the predetermined minimum distances between the rollers, said distances being necessary for applying a fiber cable. In case of a roller diameter of, for example 800 mm, the minimum distances between the rollers of approximately 150 mm are required for applying the fiber cables.

FIG. 6 schematically illustrates the side view of another embodiment of the apparatus according to the invention. Here also, a top view is omitted since the design is substantially identical to the embodiment illustrated in FIGS. 1 and 2. In this respect, reference is made to the description of FIGS. 1 and 2 and only the differences are explained below.

In the embodiment according to FIG. 6, altogether three additional rollers 4.1, 4.2 and 4.3 are arranged between a feeding roller 2 and a discharging roller 3. The arrangement is thereby selected in such a way that the feeding roller 2, the roller 4.2 and the discharging roller 3 are arranged in a first vertical plane and at a distance from one another. The rollers 4.1 and 4.3 are arranged in a second adjoining vertical plane. A minimum distance between the rollers is maintained as a result of which the roller 4.1 is arranged centrally relative to the feeding roller 2 and the roller 4.2 arranged thereabove. Accordingly, the roller 4.3 is held centrally next to the roller 4.2 and the discharging roller 3. The inlet 5 is embodied diagonally above the feeding roller 2. The outlet 6 is embodied diagonally below the discharging roller 3, so that the fiber cable 7 is guided on the feeding roller 2 and the discharging roller 3 at an angle of contact of >180°. The distance between the feeding roller 2 and the roller 4.2 arranged directly thereabove in the vertical plane is configured to be smaller than the roller diameter of the roller 4.1 so that large angles of contact of >200° are possible when guiding the fiber cable 7 from the feeding roller 2 to the additional rollers 4.1 and 4.2. Thus the total angle of contact of >1,000° can be attained using the embodiment illustrated in FIG. 6. The transition between the individual rollers is configured to be substantially equal.

For building up still greater draw forces or stretch forces even six rollers can advantageously be integrated into a apparatus according to the invention. The possible examples for the arrangement of the rollers are illustrated in the FIGS. 7 and 8. Here a horizontal inlet and outlet of the fiber cable are implemented for each of the feeding rollers 2 and the discharging rollers 3. In all other respects, reference is made to the design of the apparatus illustrated in FIGS. 1 and 2.

In the embodiment according to FIG. 7, four additional rollers 4.1, 4.2, 4.3 and 4.4 are each arranged offset relative to one another between the feeding roller 2 and the discharging roller 3. Here the roller distances between the individual rollers are configured to be equal so that the individual angles of contact result in guiding a fiber cable with a total wrap of >1,200°.

In the embodiment illustrated in FIG. 8, the six rollers are arranged in two groups, wherein the first group is formed by the feeding roller 2 and the two rollers 4.1 and 4.2 arranged downstream and offset relative to one another. The second group of the rollers comprises the discharging roller 3 and the rollers 4.3 and 4.4 arranged offset relative thereto. Here also, the fiber cable is guided on the individual rollers at angles of contact measuring between 180° and 230°.

The embodiments illustrated in the FIGS. 1 to 8 of the apparatus according to the invention can be used for drawing one or more fiber cables in a spinneret. The inlet 5 could be formed, for example, by a deflecting roller, which is arranged directly downstream of a spinneret and which merges together the individual freshly spun fiber bundles into a fiber cable. The outlet 6 could be formed, for example by a guide roller arranged directly upstream of a winder.

Furthermore, all the embodiments illustrated in the FIGS. 1 to 8 of the apparatus according to the invention can be used for drawing one or more fiber cables or for thermally treating one or more fiber cables. The rollers can comprise additional heating or cooling agents for this purpose.

Multiple apparatuses according to the invention are used in parallel for drawing one or more fiber cables, wherein said apparatuses, due to the different speeds, bring about a drawing of the fiber cables between the individual apparatuses.

Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which the invention pertains having the benefit of the teachings presented in the foregoing description and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. An apparatus for guiding, conveying, or treating a fiber cable comprising

a plurality of driven rollers positioned so that a fiber cable can be guided along the circumference of each roller so as to partially wrap therearound,

said driven rollers including a feeding roller positioned adjacent an inlet for the fiber cable, a discharging roller positioned adjacent an outlet for the fiber cable, and a plurality of additional rollers arranged relative to the feeding roller and the discharging roller so that the fiber cable can be guided on the rollers at a respective angle of contact which is >180°, and

wherein the feeding roller and the inlet for the fiber cable and the discharging roller and the outlet for the fiber cable are arranged relative to each other such that the fiber cable can be guided along the circumference of the feeding roller and the circumference of the discharging roller so as to partially wrap therearound at a respective angle of contact which is >180°.

2. The apparatus according to claim 1, wherein the fiber cable is guided on all the driven rollers so as to partly wrap therearound at a respective angle of contact of >190°.

3. The apparatus according to claim 1, wherein the angle of contact on all the rollers are of substantially equal measure.

4. The apparatus according to claim 1, wherein the angle of contact on the feeding roller and the discharging roller and/or the angle of contact on the additional rollers are of substantially equal measure.

5. The apparatus according to claim 1, wherein altogether two additional rollers are provided.

6. The apparatus according to claim 5, wherein the additional rollers are arranged between the feeding roller and the discharging roller.

7. The apparatus according to claim 5, wherein the feeding roller and the discharging roller are arranged between the additional rollers.

8. The apparatus according claim 1, wherein altogether three additional rollers are arranged between the feeding roller and the discharging roller.

9. The apparatus according to claim 1, wherein altogether more than three additional rollers are arranged between the feeding roller and the discharging roller.

10. The apparatus according to claim 1, wherein a drive motor is assigned to each of the driven rollers, and wherein the drive motors are controlled by several individual converters or by a group converter.

11. The apparatus according claim 1, wherein the rollers are mechanically coupled by toothed wheels or chains and are driven by a drive motor using a converter.