BRAIDING, WINDING OR SPIRALLING MACHINE AND METHOD FOR OPERATING SAME

Abstract

The invention relates to a method for operating a braiding, winding or spiraling machine for braiding around, wrapping around or spiraling around a strand-like material, in particular a cable, with at least one elongate material strand formed from at least one elongate material fibre, in particular from at least one wire. In the method, a diameter of the strand-like material is measured and a feed rate of the strand-like material and/or a rotational speed at which the at least one elongate material strand moves about the longitudinal axis of the strand-like material is controlled by open-loop or closed-loop control depending on said diameter measured. A predefined degree of coverage of the strand-like material by the at least one elongate material strand can be kept substantially constant by means of an open-loop or closed-loop control of the relative feed rate of the strand-like material depending on the diameter measured.

Claims

1. A method for operating a braiding, winding or spiraling machine for braiding, wrapping or spiraling at least one elongate material strand, formed from at least one elongate material fiber, in particular from at least one wire, around a strand-like material, in particular a cable, wherein the at least one elongate material strand is rotationally fixed at least at one point to the strand-like material, the at least one elongate material strand is repeatedly guided around the longitudinal axis of the strand-like material and the strand-like material simultaneously always moved in the same direction substantially in the direction of its longitudinal axis such that the at least one elongate material strand takes on the shape of a coil looping around the strand-like material, wherein a diameter of a cross section of the strand-like material is measured substantially perpendicular to its longitudinal axis and a feed rate of the strand-like material and/or a rotational speed at which the at least one elongate material strand moves around the longitudinal axis of the strand-like material is controlled or regulated as a function of said measured diameter.

2. The method for operating a braiding, winding or spiraling machine according to claim 1, wherein a relative feed rate of the strand-like material, defined as a distance by which the strand-like material moves around the longitudinal axis of the strand-like material in one complete revolution of the at least one elongate material strand, is controlled or regulated as a function of the measured diameter of the cross section of the strand-like material such that a degree of coverage of the strand-like material by the at least one elongate material strand, defined as a ratio of the total surface area of all the elongate material strands, facing radially outward with respect to the strand-like material covering the strand-like material in a specific section of said strand-like material to the surface area of the strand-like material in said section, substantially corresponds to a predefined value.

3. The method for operating a braiding, winding or spiraling machine according to claim 1, wherein the $h=\frac{1}{\sqrt{{\left(\frac{k}{\mathrm{fXd}}\right)}^2-\frac{1}{{\left(\pi D\right)}^2}}}.$ relationship is used to control or regulate the relative feed rate of the strand-like material, wherein h is the relative feed rate of the strand-like material, D the diameter of a cross section of the strand-like material substantially perpendicular to its longitudinal axis, k the degree of coverage of the strand-like material by the at least one elongate material strand, f the number of elongate material fibers in the at least one elongate material strand, d the diameter of a cross section of an elongate material fiber substantially perpendicular to its longitudinal axis, and X the number of elongate material strands to be factored into the degree of coverage.

4. The method for operating a braiding, winding or spiraling machine according to claim 2, wherein a twist angle, defined as an angle between a half-line running parallel to the longitudinal axis of the strand-like material and opposite to the direction of movement of the strand-like material through the take-up point of the at least one elongate material on the strand-like material and the at least one elongate material being taken up on the strand-like material, is measured and used in controlling or regulating the relative feed rate of the strand-like material.

5. The method for operating a braiding, winding or spiraling machine according to claim 4, wherein the $\alpha ={\tan }^{-1}\sqrt{{\left(\frac{k\pi D}{\mathrm{fXd}}\right)}^2-1}.$ relationship is used to control or regulate the relative feed rate of the strand-like material using the twist angle, wherein α is the twist angle, D the diameter of a cross section of the strand-like material substantially perpendicular to its longitudinal axis, k the degree of coverage of the strand-like material by the at least one elongate material strand, f the number of elongate material fibers in the at least one elongate material strand, d the diameter of a cross section of an elongate material fiber substantially perpendicular to its longitudinal axis, and X the number of elongate material strands be factored into the degree of coverage.

6. A braiding, winding or spiraling machine configured to be operated according to a method for braiding, wrapping or respectively spiraling at least one elongate material strand made from at least one elongate material fiber, in particular from at least one wire, around a strand-like material, in particular a cable, wherein the at least one elongate material strand is rotationally fixed at least at one point to the strand-like material, the at least one elongate material strand is repeatedly guided around the longitudinal axis of the strand-like material and the strand-like material simultaneously always moved in the same direction substantially in the direction of its longitudinal axis such that the at least one elongate material strand takes on the shape of a coil looping around the strand-like material, characterized in that a diameter of a cross section of the strand-like material is measured substantially perpendicular to its longitudinal axis and a feed rate of the strand-like material and/or a rotational speed at which the at least one elongate material strand moves around the longitudinal axis of the strand-like material is controlled or regulated as a function of said measured diameter, and wherein the braiding, winding or spiraling machine is also configured to repeatedly guide the at least one elongate material strand around the longitudinal axis of the strand-like material and simultaneously always move the strand-like material in the same direction substantially in the direction of its longitudinal axis, characterized by a measuring apparatus for a diameter of a cross section of the strand-like material substantially perpendicular to its longitudinal axis and a control or regulating apparatus for controlling or regulating a relative feed rate of the strand-like material, defined as a distance by which the strand-like material moves upon a complete revolution of the at least one elongate material strand around the longitudinal axis of the strand-like material subject to said measured diameter.

7. The braiding, winding or spiraling machine according to claim 6, additionally configured to be operated according to a method wherein a twist angle, defined as an angle between a half-line running parallel to the longitudinal axis of the strand-like material and opposite to the direction of movement of the strand-like material through the take-up point of the at least one elongate material on the strand-like material and the at least one elongate material being taken up on the strand-like material, is measured and used in controlling or regulating the relative feed rate of the strand-like material, and which furthermore comprises a measuring device for the twist angle.

8. The braiding, winding or spiraling machine according to claim 6, additionally configured to be operated according to a method wherein the $\alpha ={\tan }^{-1}\sqrt{{\left(\frac{k\pi D}{\mathrm{fXd}}\right)}^2-1}.$ relationship is used to control or regulate the relative feed rate of the strand-like material using the twist angle, wherein α is the twist angle, D the diameter of a cross section of the strand-like material substantially perpendicular to its longitudinal axis, k the degree of coverage of the strand-like material by the at least one elongate material strand, f the number of elongate material fibers in the at least one elongate material strand, d the diameter of a cross section of an elongate material fiber substantially perpendicular to its longitudinal axis, and X the number of elongate material strands to be factored into the degree of coverage, and wherein the braiding, winding or spiraling machine furthermore comprises a measuring device for the twist angle.

Description

[0060] Further advantages, features and possible applications of the present invention will become apparent from the following description in conjunction with the figures.

[0061] Shown are:

[0062] FIG. 1: a drawing of a rectangular “pay-off” of the surface of the strand-like material;

[0063] FIG. 2: a schematic configuration of a braiding machine of the type under consideration.

[0064] FIG. 1 has already been explained above.

[0065] FIG. 2 shows the functional principle of an inventive braiding machine 1 on the basis of a schematic drawing.

[0066] The braiding machine 1 comprises a number, for example 8, 12 or 16, of upper braiding bobbins 2, onto each of which an upper yarn 9 (the so-called weft) is wound. The upper yarn 9 can in particular be a textile strand, a wire or a bundle of several such textile strands or wires. The upper braiding bobbins 2 are mounted on bobbin carriers (not shown) which rotate separately from each other on gearwheels on a ring gear (neither shown) mounted on a lower bobbin rail 4 and all rotate in the same direction, for example counterclockwise (indicated by upper rotating arrow 17).

[0067] Furthermore, the braiding machine 1 comprises a number, for example likewise 8, 12 or 16, of lower braiding bobbins 3, onto each of which a lower yarn 10 (the so-called warp) is wound. The number of lower braiding bobbins 3 is thereby preferably the same as the number of upper braiding bobbins 2. The lower yarn 10 is preferably the same yarn as the upper yarn 9. The lower braiding bobbins 3 are mounted on a common lower bobbin rail 4 which rotates in a direction opposite to the upper braiding bobbins 2, for example clockwise (indicated by lower rotating arrow 18).

[0068] The axis around which the upper braiding bobbins 2 and lower braiding bobbins 3 rotate together albeit in opposite directions coincides with the so-called braid axis 5. A cable 6—still unshielded at this point—is introduced into the braiding machine 1 along the braid axis 5 from below and continues on out of the braiding machine 1 at the upper end thereof.

[0069] The upper yarns 9 paying off the upper braiding bobbins 2 and the lower yarns 10 paying off the lower braiding bobbins 3 converge at braiding point 8 on the braid axis 5 and wrap around the unshielded cable 6 there, which is then pulled off the upper end of the braiding machine 1 as a shielded cable 7 by a (not shown) haul-off capstan.

[0070] So that the upper yarns 9 and the lower yarns 10 cross at braiding point 8 and are thereby braided, the lower yarns 10, which rotate with lower braiding bobbins 3 in the opposite direction about braid axis 5 than upper yarns 9 with upper braiding bobbins 2, are alternatingly passed over one or more adjacent upper braiding bobbins 2 and under one or more adjacent upper braiding bobbins 2, for example above or respectively below two adjacent upper braiding bobbins 2. During the up and down bobbing motion, each lower yarn 10 dips into vertical slots in an upper inner housing 19.

[0071] The lower yarn 10 runs over a roller at one end of a braiding lever 11 and is alternatingly lifted or depressed by the braiding lever 11 prior to passing an “oncoming” upper bobbin 2 and thus passed over the upper braiding bobbin 2 or under the upper braiding bobbin 2 respectively. To this end, each lower yarn 10 is allocated its own braiding lever 11 respectively rotatable about a pivot bearing 12 fixed to a mount 13 connected to the lower bobbin rail 4.

[0072] Each braiding lever 11 is controllable via a connecting rod 14, the upper end of which is rotatably connected to the braiding lever 11 and the lower end of which runs in a fixed circumferential curved path of a cam control 15. The waveform of the cam control 15 curved path results in an up and down sliding movement of the connecting rod 14 and thus to the desired up and down tilting of the braiding lever 11, which is synchronized with the movement of the upper braiding bobbins 2. Alternatively, however, the braiding lever 11 can also be directly guided in the curved path of the cam control 15.

[0073] A diameter measuring device 16 which measures the diameter of a cross section of the cable 6 substantially perpendicular to the braid axis 5 is arranged anywhere along the braid axis 5 at which the cable 6 is not yet braided and therefore still unshielded. The diameter is thereby preferably measured continuously, although it can also ensue periodically at a specific frequency.

[0074] The diameter is measured by means of a suitable measuring means, preferably mechanically, for instance by means of two spring-loaded rollers pressed against two opposite sides of the cable 6 from the outside via spring action. The distance between the two rollers and thus the diameter of the cable 6 can for example be determined by the spring tension with which the two rollers are pushed apart or even by an optical or other measuring range transducer. Further preferentially, the diameter measurement can also ensue on a purely optical basis, for instance by means of a laser sensor, alternatively also by means of a camera which continuously films the passing cable 6, the images of which are evaluated.

[0075] The braiding machine 1 can in addition also comprise a (not depicted) measuring device for the twist angle α.

[0076] The inventive method is preferably stored in a control device of the braiding machine 1 as control software. When commencing operation, the operator of the braiding machine 1 enters a setpoint for the degree of coverage k into the controller. The diameter D of the cable 6 can also be input into the controller as a setpoint value. Alternatively, the measured diameter D can also be transferred to the controller.

[0077] Calculated therefrom—preferably using the mathematical relationship indicated above—is a setpoint h.sub.soll for the relative feed rate h of the cable 6; i.e. the distance by which the cable 6 advances during one complete revolution of the upper braiding bobbins 2 or the lower braiding bobbins 3 about the braid axis 5. A v.sub.soll,1 setpoint is determined from the h.sub.soll setpoint for the rotational speed of the upper braiding bobbins 2 or lower braiding bobbins 3 rotation about the braid axis 5 as is a v.sub.soll,2 setpoint for the haul-off speed of the braided shielded cable 7. To that end, v.sub.soll,1 is preferably first set to the maximum permissible rotational speed and then v.sub.soll,2=h.sub.soll˜v.sub.soll,1, such that: h.sub.soll=v.sub.soll,2/v.sub.soll,1. Should v.sub.soll,2 then exceed the maximum permissible haul-off speed, both v.sub.soll,1 as well as v.sub.soll,2 are reduced at the same rate until v.sub.soll,2 is also within the permissible range.

[0078] The thusly determined v.sub.soll,1 and v.sub.soll,2 values are transferred to the respective controller as setpoint values for the rotational speed of the braiding bobbins 2, 3 or the haul-off speed respectively. The respective controller then controls or regulates the rotational speed/haul-off speed to the v.sub.soll,1/v.sub.soll,2 value. This thus thereby ensures that the braided cable 7 substantially exhibits the predefined degree of coverage k.

[0079] Should the braiding machine 1 comprise a measuring device for the twist angle α, an α.sub.soll setpoint can be calculated—preferably using the mathematical relationship indicated above—for said twist angle α. After that, the rotational speed of the braiding bobbins 2, 3 can be changed and simultaneously the twist angle α measured, e.g. at a constant haul-off speed of the braided cable 7, until the twist angle α has assumed the α.sub.soll setpoint value. This thus also ensures that braided cable 7 substantially exhibits the predefined degree of coverage k.

LIST OF REFERENCE NUMERALS

[0080] 1 braiding machine [0081] 2 upper braiding bobbin [0082] 3 lower braiding bobbin [0083] 4 lower bobbin rail [0084] 5 braid axis [0085] 6 unshielded cable [0086] 7 shielded cable [0087] 8 braiding point [0088] 9 upper yarn (weft) [0089] 10 lower yarn (warp) [0090] 11 braiding lever [0091] 12 braiding lever pivot bearing [0092] 13 braiding lever mount [0093] 14 connecting rod for braiding lever control [0094] 15 braiding lever cam control [0095] 16 diameter measuring device [0096] 17 upper braiding bobbin direction of rotation [0097] 18 lower braiding bobbin direction of rotation [0098] 19 upper inner housing [0099] 20 lower inner housing