Wire cable and method and device for production of said wire cable

Abstract

A wire cable and a device and method for producing the wire cable, wherein a core strand is compacted and then braid strands are stranded on the core strand. The core strand is hammered before stranding of the braid strands in order to smooth the surface thereof. A plastic layer is applied to the core strand before stranding of the braid strands. The braid strands are pressed into the plastic layer while the plastic layer is heated. The core strand is a core cable and the braid strands are strands of the wire cable or the core strand is a heart strand and the braid strands are outer core strands of a core cable of the wire cable. A greater breaking strength of the wire cable is obtained by hammering the core strand in order to smooth it than by compacting a core strand with a roller compressor.

Claims

1. A method for producing a wire cable, comprising the steps of: precompacting a core cable and afterwards compacting the core cable by hammering to smooth an outer surface of the core cable and increase flexibility and bending strength of the wire cable; applying a plastic layer to the core cable; softening the plastic layer; subsequently twisting multiwire strands onto the core cable covered by the softened plastic layer and pressing the multiwire strands into the softened plastic layer; and hammering the wire cable after the multiwire strands are twisted on the core cable and pressed into the plastic layer.

2. The method according to claim 1, wherein the core cable is precompacted by a roll compactor or a draw plate.

3. A wire cable, comprising: a core cable precompacted and subsequently compacted by hammering to smooth an outer surface of the core cable and increase flexibility and bending strength of the wire cable; a plastic layer applied on the core cable; and multiwire strands twisted onto the core cable and pressed into the plastic layer, wherein the wire cable is hammered after the multiwire strands are twisted onto the core cable and pressed into the plastic layer.

4. A method for producing a wire cable, comprising the steps of: twisting wires at a twisting point into a core strand; hammering the core strand for increasing flexibility and bending strength of the wire cable at a certain distance away from the twisting point, the certain distance being such that, with respect to a helical arrangement in the core strand, the wires have already assumed a fixed position in a longitudinal direction of the core strand and are deformed into a helix of smaller diameter, in which lengths of wire or of multiwire strand needed to form the helix are reduced; and subsequently twisting multiwire strands on the core strand and subsequently hammering the wire cable after the multiwire strands are twisted onto the core strand.

5. A wire cable, comprising: a core strand formed of twisted wires at a twisting point, the core strand being hammered for increased flexibility and bending strength of the wire cable and for smoothening an outer surface of the core strand, wherein the core strand is hammered in a certain distance away from the twisting point, the certain distance being such that, with respect to a helical arrangement in the core strand, the wires have already assumed a fixed position in a longitudinal direction of the core strand and are deformed into a helix of smaller diameter, in which lengths of wire or of multiwire strand needed to form the helix are reduced; and multiwire strands twisted onto the core strand, wherein the wire cable is hammered after twisting of the muitiwire strands onto the core strand.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 shows a device according to the invention for the production of a wire cable;

(2) FIG. 2 shows another device according to the invention for the production of a wire cable;

(3) FIG. 3 shows another device according to the invention for the production of a wire cable;

(4) FIG. 4 shows a cross section of a wire cable according to the invention; and

(5) FIG. 5 shows a cross section of another wire cable according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

(6) A device according to the invention as shown in FIG. 1 has a twisting basket 15, over which outer multiwire core cable strands 5, 6 are guided in rotating fashion to a twisting point 20, where the outer multiwire core cable strands 5, 6 are wound around a multiwire heart strand 4 to form jointly a core cable 3, which is provided for a wire cable 1.

(7) Downstream, with respect to the twisting direction, from the twisting point 20, a roll compactor 9 is arranged, by means of which the core cable 3, formed out of the multiwire heart strand 4 and the outer multiwire core strands 5, 6, is precompacted. Downstream from the roll compactor 9, hammers 12 are provided, which strike the core cable 3 simultaneously to smooth its surface and to compact it even more. The hammers 12 (not shown in detail) comprise circular concavities, which are adapted in their shape to the cross-sectional form of the core cable to be approximated by the hammering.

(8) Downstream from the hammers 12, traction rolls 17 are provided in the device, by means of which the core cable 3 is first conveyed to a coating unit 19, where the core cable 3 is coated with a plastic layer 7 of thermoplastic material. After that, a twisting device comprising a twisting basket 16 is used to twist the core cable 3 together with outer multiwire cable strands 2 at a second twisting point 18. During the twisting process, the outer multiwire strands are pressed into the plastic layer 7, which may still be soft after its application to the core cable 3, or it may have been heated by a heating device (not shown) to soften it; the wires are pressed in so far that they rest on the core cable 3. Optionally, the device can be provided with the hammers 13, shown in a box in broken outline, by means of which the wire cable formed out of the core cable 3 and the outer multiwire strands 3 can be subjected to further hammering to compact it and to smooth its surface.

(9) As can be seen in FIG. 4, which shows a wire cable 1 produced by means of the device according to FIG. 1, the external contour of the core cable 3 has been smoothed by the hammering treatment with the hammers 12, so that it approximates the form of a circle. The plastic layer 7 is provided in the area between the core cable 3 and the outer multiwire cable strands 2.

(10) The wire cable 1 shown has not been processed by the hammers 13, so that the outer multiwire cable strands 2 still have their original round shape. In comparison to a wire cable with a core cable which has not been hammered, the wire cable 1 comprises a much higher breaking strength and a much greater elongation at break.

(11) Another device according to the invention, shown in FIG. 2, differs from that according to FIG. 1 in that hammers 12a are arranged directly downstream from a twisting point 20a, where the multiwire heart strand 4a is twisted together with the outer multiwire core strands 5a, 6a to form a core cable 3. In the same way, hammers 13a, provided only as an option in this case, are arranged directly downstream from the twisting point to process a wire cable la consisting of the core cable 3a onto which the outer multiwire cable strands 2a have been twisted at a twisting point 18a.

(12) Another device according to the invention, shown in FIG. 3, differs from those according to FIGS. 1 and 2 in particular in that additional hammers 14 are provided to process the multiwire heart strand 4b, produced from wires 22, 23 by means of a twisting mechanism 25. The device also comprises a coating unit 24 for coating the multiwire heart strand 4b with a plastic layer 8. Optionally, it is also possible here to provide a heating device (not shown) for the plastic layer 8, so that the multiwire core strands 6b can be pressed into the softened thermoplastic material forming the plastic layer 8 as they are being twisted onto the multiwire heart strand 4b.

(13) A wire cable 1b produced by means of the device according to FIG. 3, which cable comprises the hammered multiwire heart strand 4b and the hammered multiwire core strands 5b, 6b as well as hammered multiwire strands 2b, is shown in cross section in FIG. 5. The wire cable 1b comprises a breaking strength and elongation at break which are even greater than those of the wire cable 1 according to FIG. 4.

(14) In additional exemplary embodiments (not shown), the devices according to FIGS. 1-3 are not provided with the coating units 19, 19a, 19b, or 24, and the wire cables are thus produced by the associated methods without a plastic layer. The wire cables produced by means of the device or method according to the invention then comprise, accordingly, the cross sections shown in FIGS. 4 and 5 but without the plastic layer.