US2106803A - Apparatus for handling strands - Google Patents

Description

Feb. 1, 1938. F. v. JOHNSON ET AL I APPARATUS FOR HANDLING STRANDS 2 Sheets-Sheet l Filed Oct. 20, 1936 l N lfb.

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F. V. JOHNSON ET AL APPARATUS FOR HANDLING STRANDS Filed Oct. 20, 1938 I 2 Sheets-Sheet 2 /lf/VENTOI'M` F. V. JOHNSON RJ?. NYDEGGER "m SW1-LA,...

A TTRNEY iiitiiTD STATES cargar orrics APPARATUS Foa HANDLING s'rnANns Fred V. Johnson, Baltimore, Md., and Roland R.

Nydegger, Wilmington, Del., assignors to Western Electric Company, Incorporated, New York, N. Y., a corporation of NewYork Application October 20, 1936, Serial No. 106,528

7 Claims.

This invention relates to a method of and apparatus for handling strands and more particularly to a method of and apparatus for combining strands to form an electric cable.

In the manufacture of multi-conductor electric cables such as are used in the communications arts, it has been customary in some instances to mount supply reels containing strands to be twisted together, within a rotatable frame or cage. The strands are -drawn from the supply reels, brought together and guided out of the cage along the axis of rotation of the cage and intertwisted by the rotation of the cage. In so doing an individual twist is imposed on each strand having one turn for each rotation of the cage; and if the strand in question happens to be of a nature to resist the imposition of twist, it will absorb the twist by assuming a helical form until the stress of the accumulated twist overcomes the resistance and the strand yields, receiving in a short length all the twist which should be distributed evenly over a much greater length. This effect may be troublesome overcome particularly in the case of a cable having coaxial conductor units as component parts.

An object of the present invention is to provide a method of and apparatus for combining strands by which strands having a relatively high degree of. torsional rigidity may be combined, alone or with other strands of other kinds, in such fashion that deformation imposed on individual strands will be distributed evenly along the strands even though they be of relatively high torsional rigidity.

One embodiment of the invention contemplates a method of and an apparatus for intertwisting strands in which one or more oi the strands in question are prevented from any substantial lateral deformation or movement out of a predetermined path immediately and for some distance before they approach the point at which they are twisted together.

Other objects and features of the invention will appear from the following detailed description of one embodiment thereof taken in connection with the accompanying drawings, in which the same reference numerals are appended to identical parts in the several gures and in which Fig. l is a view in vertical axial section of an apparatus for intertwisting strands, constructed in accordance with the invention;

Fig. 2 is a broken view in side elevation of a portion of cable produced by the apparatus of Fig. l;

Fig. 3 is an enlarged section on the line 3 3 of Fig. 2;

Fig. 4 is an enlarged detached view in side elevation of the strand guide of Fig. 1 with its supports;

Fig. 5 is an enlarged detached view in perspective of the forward assembly collar thereof;

Fig, 6 is a section on the line 6--6 of Fig. 4, and

Fig. 7 is a section on the line l-l of Fig. 4.

In the embodiment of the invention herein shown, Fig. 1 discloses diagrammatically, -the supply end of a cable stranding machine of simple and well known form. The take-up and possible intermediate portions are not shown, being irrelevant to the invention, but may be of any suitable and well known construction and mode of operation.

'I'he portion disclosed comprises fundamentally a. rotatable cage journalled in supports 2|, 22 and driven by a sprocket chain 23 from a shaft 24 driven in turn by a motor not shown. Within the cage 20 is mounted a plurality of spools or reels to supply the component strands of the cable to be manufactured. In the example disclosed, these consist of two reels 25 and 26 containing supplies of coaxial conductor unts 30 and 3| respectively, two reels to supply two four conductor auxiliary strands 32 and 33 of which only one reel 21 is shown in Fig. l, and four reels to supply four relatively soft nonmetallic iiller strands 34, 35, 36 and 3l of which only two reels 28 and 29 are shown. x

A right hand bearing member 38 of the cage has an axial passageway in which is positioned a strand guide generally indicated by the numeral 39. The body of this guide consists of two tubes 40 and 4| of internal diameter triiiing- 1y greater than the external diameter of the identically similar coaxial units 30 and 3| which pass freely through the tubes but are constrained therein against any lateral distortion. The tubes preferably have bell mouthed entrance members 42 and 43 secured thereon. The tubes are rigidly mounted in a mounting plate 44 secured to the cage 20 so that the tubes rotate with the cage. 'Ihe plate 44 is further provided with appropriate apertures about the tubes to permit the other strands 32, 33, 34, 35, 36 and 3l to pass in a direction generally parallel to the tubes and their contained strands 30 and 3|.

Near the outer or right hand end of the tubes 40 and'4l these are rigidly mounted in a journal member 45 supported in a crossbar 4G. The member 45 rotates with the tubes 40 and 4| within the crossbar 46, and is provided with two apertures in which the tubes 40 and 4| are mounted and with six other apertures to pass the remaining strands of the cable to be.

On the extreme outer ends of the tubes is mounted a twisting head 4l having a plurality of passages therethrough, corresponding in number and size to the component strands of the cable to be. Each passage leads from the corresponding aperture of the `journal member at the left or entrance end of the head 4l to blend into a single axial opening at the right or exit end oi the head, where the component strands are applied to each other and are twisted together by the rotation of the'cage.

The crossbar 46 is secured on the outer end of a journal member 48 rotatably mounted in a bracket 49 secured on the support 22. This member 48 is coaxial with the member 33 and has an axial passage to house the guide 38. A serving head 50 for applying a wrapping of paper tapes 5| and 52 over the intertwisted strands is mounted on the member 48 which is driven in rotation in the opposite direction to that of the cage 20 by a sprocket chain 53 from the shaft 24.

The coaxial unit 30 shown consists of an inner axial conductor 55 and an outer hollow conductor 56 spaced apart bya plurality of insulating disks 5l. The unit 3| shown is of similar structure.

In operation the finished product 58 of the apparatus shown is drawn along to the right (Fig. l) by any appropriate means not shown, while the shaft 24 is rotated. The cage 20 then rotates say counterclockwise as seen from the right and the serving unit 50 rotates in the opposite direction. The eight strands 30, 3|, 32, 33, 34, 35, 36 and 31 are drawn from their respective supply reels, the two coaxial units 30 and 3| passing through tne guide tubes 40 and 4| respectively and the other six strands passing through the corresponding apertures in the members 44, 45 and 41. In passing through the twisting head 4l the eight strands are combined in the relation shown in Figs. 2 and 3 and on emerging from the head 4l are twisted'together and immediately wrapped with the tapes 5| and 52.

Each revolution of the cage 2|) eiects one turn of the lay of the cable, i. e. of the intertwist of K the cable components, but each revolution of the cage also tends to impose one turn of individual twist upon each strand by itself. The textile strands 34, 35, 36 and 3l naturally accept this twist without resistance and the four conductor cables 32'and 33 are ordinarily of such nature as to do so also. But a coaxial conductor strand, such as 30 or 3|, is ordinarily far more rigid in torsion than the others and therefore tends to resist the imposition of this twist and to escape it partially by taking on a helical form. This helix then tends to be pushed back after being formed and to pile up at the guide sheave or even back at the supply reel. This piling up continues until, in the worst forms, the strand yeids abruptly, kinks and jams, or, in milder cases, a short length of the strand is sharply twisted and absorbs allthe twist that should properly be distributed evenly over a vastly greater length. In the latter case the sharp twisting may very well rupture one or both conductors of the strand.

In the present invention, however, it is found that, if the helix distortion is never permitted to begin but the strand is forced to run straight for a considerable distance up to the twisting point, the strand will accept the imposed twist evenly and will enter into and lie in the cable evenly and with uniform properties along its length.

As herein disclosed, the invention is applied to the manufacture of a cable consisting of two coaxial conductor units, two four conductor escasos ordinary units, and four textile ller strands with a wrapping of two paper tapes. Obviously, however, the number of each kind'of strandl is immaterial to 'the invention which is applicable and useful wherever a strand oi.' high torsional rigidity is to be intertwisted with one or more other strands.

The embodiment herein disclosed is merely illustrative and may be modied and departed from in many ways without departing from the spirit and scope of the invention as pointed out in and limited solely by the appended claims.

What is claimed is:

1. An apparatus for combining strands which comprises a rotatable frame, a plurality of strand supplies in the frame, and a strand delivery guide mounted axially of `the frame to receive the strands and deliver them from the frame, the said guide comprising an elongated hollow member to receive and pass one o! the strands and having a passage therefor suiilciently narrow to prevent lateral deformation of the strand therein.

2. An apparatus for combining strands which comprises a rotatable frame, a plurality of' strand upplies in the frame, and a strand delivery guide mounted axially of the frame to receive the strands and deliver them from the frame, the said guide comprising a plurality oi.' elongated hollow members each to receive and pass one of the strands and having a passage therefor suiiiciently narrow to prevent lateral defamation of the strand therein.

3. In a strand handling apparatus, guiding:

means for a longitudinally advancing stran:.`. 2.1.5.

which comprises an elongated member formen' with a passage therethrough dimensioned to permit the strand to pass freely through the passage but to be prevented from lateral deformation while in the passage.

4. In a strand handling apparatus, guiding means for a longitudinally advancing strand which comprises an elongated member formed with a cylindrical passage therethrough dimen sioned to permit the strand to pass freely through the passage but to be prevented from lateral deformation while in the passage.

5. In a strand handling apparatus, guiding means for a plurality of longitudinally advancing strands which comprises a pluralityof elongated members each formed with a passage therethrough dimensioned to permit one of the strands to pass freely through the passage but to be prevented from lateral deformation while in the passage.

6. In a strand handling apparatus, guiding means for a plurality of longitudinally advancing strands which comprises a plurality of elongated members each formed with a cylindrical passage therethrough dimensioned to permit one of the strands tovpass freely through the passage but to be prevented from lateral deformation while in the passage.

'7. In a strand handling apparatus, guiding means for a plurality of longitudinally advancing strands which comprises a plurality of elongated members each formed with a cylindrical passage therethrough dimensioned to permit one of the strands to pass freely through the passage but to be prevented from lateral deformation while in the passage, the several passages being mutually parallel.

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