Device for guiding fibre tows through oxidation furnaces

Abstract

The invention relates to an apparatus for passing at least one fiber tow multiple times through an oxidation furnace by means of godets, the at least one fiber tow being diverted via at least one godet that is arranged offset. According to the invention, the godet comprises a shaft on which at least two single rollers are arranged to be mounted, each single roller being arranged so as to be rotatable on the shaft.

Claims

1. An apparatus for passing at least one fiber tow multiple times through an oxidation furnace, comprising: at least a first and at least a second godet arranged opposite to each other, the at least first godet comprising a first shaft and the at least second godet comprising a second shaft, wherein the first shaft is arranged angularly offset relative to the second shaft so that the at least one fiber tow is diverted by the at least first godet, wherein at least the first shaft is a straight shaft, wherein the at least first godet further comprises at least two single rollers arranged rotatable on the first straight shaft; wherein each of the at least two single rollers has a first end face and a first shoulder at least in a region of the first end face; wherein at least one of the two single rollers has a depression in the region of the first end face having the first shoulder, into which depression a second end face of another one of the at least two single rollers is received.

2. The apparatus according to claim 1, wherein the second end face has a second shoulder.

3. The apparatus according to claim 2, wherein the first and second shoulders are differently configured.

4. The apparatus according to claim 1, wherein the depression has one of a conical or concave contour.

5. The apparatus according to claim 1, wherein the second end face of said another one of the at least two single rollers has one of a conical or convex contour complementary to the depression.

6. The apparatus according to claim 1, wherein each of the single rollers is mountable on the shaft with a bearing.

Description

(1) The invention is described in greater detail below with reference to a possible exemplary embodiment which is shown diagrammatically in the drawings, wherein

(2) FIG. 1: is a diagrammatic plan view of an oxidation furnace having godets on both sides;

(3) FIG. 2: shows a pair of godets according to the invention without the oxidation furnace;

(4) FIG. 3: is a detail view of the rollers or godets;

(5) FIG. 4: is a partial section through a godet having single rollers;

(6) FIG. 5: shows the godets according to the invention used as a drawing mechanism.

(7) FIG. 1 is a diagrammatic plan view of an oxidation furnace 1 having godets 2a, 2b on both sides and the fibre tow 3 running thereon. The fibre tow 3, coming from the left, is supplied to the oxidation furnace 1 and, after a plurality of passes, leaves the oxidation furnace 1 displaced horizontally on the right-hand side. It is also possible, however, for the fibre tow 3 to leave the oxidation furnace 1 on the left-hand side if this is required by the process or the local conditions.

(8) FIG. 2 again shows a pair of godets 2a, 2b with a fibre tow 3. Each godet 2a, 2b consists of at least two single rollers 4a, 4b which are arranged to be mounted on shafts 5a and 5b. In this exemplary embodiment five single rollers 4a, 4b are mounted on each shaft 5a, 5b. Depending upon the dimensions of the oxidation furnace 1 it is also possible to arrange a smaller or larger number of single rollers 4a, 4b on shafts 5a, 5b.

(9) The shafts 5a, 5b are fixed in a holding means (not shown) at both ends but can also be mounted only at one end. The holding means are arranged to be displaceable, so that the angular position necessary for the desired displacement can be adjusted. For better understanding, the upper filament run, where the fibre tow 3 runs from left to right, is shown as a solid line, and the lower filament run, where the fibre tow 3 runs from right to left, is shown as a dotted line.

(10) The physical principle for the displacement of the fibre tow 3 is illustrated in FIG. 3. As a result of the transverse forces that occur, a filament or a fibre tow 3 always seeks to run onto a rotating roller or godet 2b perpendicularly at an angle of 90°. The actual change in the direction of fibre travel takes place where the filament or fibre tow 3 runs off the roller, when the frictional forces between the fibre tow 3 and the surface of the roller are no longer sufficient to offer resistance to the axial transverse forces. The fibre tow 3 then slips until the fibre tow 3, which was previously running radially over the roller, forms a straight line at an angle perpendicular to the roller located opposite.

(11) To provide support during set-up and adjustment of the godets 2a, 2b, the single rollers 4a, 4b have a large shoulder 7b in the region of a first end face and a small shoulder 7a in the region of the second end face. The single roller 4a, 4b has, in the region of the first end face on which the large shoulder 7b is arranged, a depression 8 into which the small shoulder 7a is able to fit. This prevents the fibre tow 3 from slipping into the gap 6 between two single rollers 4a and becoming jammed therein.

(12) The large shoulder 7b therefore covers the small shoulder 7a of the adjacent single roller 4a, 4b like a sleeve. Self-centering is achieved by the second end face of the single roller 4a, 4b, which has the small shoulder 7a, having a conical or convex contour. Complementary thereto, the depression 8 on the first end face having the large shoulder 7b is likewise of conical or concave construction.

(13) It will be understood that, depending upon the desired number of passes through the oxidation furnace 1, the single rollers 4a, 4b are exchangeable and have different widths. The single rollers 4a, 4b used will logically always have a width a multiple of which corresponds to the total width of the oxidation furnace 1 or the width of a godet 2a, 2b.

(14) In order to equalise the horizontal displacement resulting from the wrapping, it is possible to use drawing mechanisms 9 likewise in the form of godets which, as shown in FIG. 5, are directed towards the rear. As a result, the fibre tow 3 is guided towards the rear again, with the elegant result that, in the case of a plurality of oxidation furnaces 1 arranged one after the other, the oxidation furnaces 1 are aligned in a row, which significantly facilitates operation and maintenance.

REFERENCE NUMERALS

(15) 1 oxidation furnace 2a, 2b godets 3 fibre tow 4a, 4b single roller 5a, 5b shaft 6 gap 7a small shoulder 7b large shoulder 8 depression 9 drawing mechanism