US3494386A

US3494386A - Continuous pay-out devices for wire and the like

Info

Publication number: US3494386A
Application number: US639425A
Authority: US
Inventors: Leonard Albert Waters
Original assignee: Post Office
Current assignee: Post Office
Priority date: 1966-05-27
Filing date: 1967-05-18
Publication date: 1970-02-10
Anticipated expiration: 1987-02-10
Also published as: GB1189301A

Description

Feb. 10, 1970 1.. A. WATERS 3,494,386

CONTINUOUS PAY-OUT DEVICES FOR WIRE AND THE LIKE V Filed May 18. 1967 5 Shets-Sheet 1 Lia/mm A. WATERS INVENTOR BY r ATTORNEY Feb. 10, 1970 L. A. WATERS 3,494,386

CONTINUOUS PAY-OUT DEVICES FOR WIRE AND THE LIKE Filed May 18, 196? 3 Sheets-Sheet I INVENTOR ATTORNEY Feb. 10, 1970 L. A. WATERS 85 CONTINUOUS PAY-OUT DEVICES FOR WIRE AND THE LI KE Filed May 18, 196'? s Sheets-Sheet a Z0M7FD 9. Mimi's,

INVENTOR ATTORNEY United States Patent 3,494,386 CONTINUOUS PAY-OUT DEVICES FOR WIRE AND THE LIKE Leonard Albert Waters, Wembley, England, assignor to Her Majestys Postmaster General, London, England Filed May 18, 1967, Ser. No. 639,425 Claims priority, application Great Britain, May 27, 1966, 23,959/ 66 Int. Cl. B21d 3/12; B21f 21/00, 1/02 U.S. Cl. 140149 6 Claims ABSTRACT OF THE DISCLOSURE Apparatus, using suitably oriented and rotated wheels and pulleys, for twisting wire about its longitudinal axis so that, in continuous pay-out devices for use in the controlled laying of submarine cables by the taut-wire technique, inherent twists in the wire are transferred from the low tension end to the high tension end of the equipment and smooth running ensues.

This invention relates to continuous pay-out devices for wire and the like and more particularly to apparatus fol ensuring smooth drawing-off of wire for use in the controlled laying of submarine cables by the taut-Wire technique.

In the laying of submarine cables it is necessary to lay a length of cable greater than the point-to-point distance between the cable terminals to ensure that the cable is not suspended over depressions in the sea-bed and that a bight of cable can be lifted during repair operations. The excess length over the point-to-point distance is termed the slack and it is clearly important that the cable must be controlled during the lay so that the planned slack is in fact laid. The most accurate practical method of ensuring that the correct amount of slack is paid out is the taut-wire technique.

The taut-wire technique relies on laying a continuous wire of about 22 SWG under relatively high tension. It is assumed that, once several miles of wire have been paid out from a sinker, the length of wire being paid out is equal to the ground distance covered. That assumption is reasonably valid for small angles of depression of the wire from the horizontal and for small angles of slope of the sea-bed. The taut wire then provides a continuous measurement of ground distance, and measurement of the length of wire and the length of cable paid out enables slack to be determined directly.

Essential features of the taut-wire technique are that the wire must run smoothly and without interruption. A method has been devised for joining lengths of wire, supplied coiled in drums, to achieve a continuous run. This method consists in bringing the inner end of the first coil of wire to the outside of the first drum and joining it to the outer end of the second coil of wire. Means are provided for directing the wire as it transfers from one drum to the next and for replacing the drums as they are used. This arrangement precludes the rotation of the drums as the wire is drawn off and consequently causes a build-up of twists in the low tension (drawing-off) end of the wire which eventually cause kinks or snarls.

It is an object of the present invention to provide apparatus for transferring the inherent twists in a wire from the low tension end to the high tension end of the equipice ment so that kinks cannot form and so that the wire runs smoothly.

According to the present invention such apparatus for transferring inherent twists in a wire, one end of which is under tension, from the low tension end to the high tension end comprises first guiding means for directing the wire into and around part at least of the groove of a grooved Wheel, and second guiding means for directing the wire from the grooved wheel to the high tension end of the apparatus, the grooved wheel being so mounted that the enforced passage of wire through the apparatus causes rotation of the grooved wheel in at least one plane such that inherent twists in the low tension end of the wire pass through' the apparatus to the high tension end of the wire.

In a first embodiment of the invention, the grooved wheel rotates only about its own axis of revolution and the apparatus then includes a hollow axle carrying a first pulley adjacent one end thereof attached to and rotatable with the axle, a second pulley adjacent the other end of the axle coupled with the first pulley and free to rotate on the axle, and, adjacent the second pulley, the grooved wheel attached to the axle to be rotatable therewith, the second pulley having mounted thereon the second guiding means for directing the wire from the grooved wheel to the high tension end of the apparatus, the enforced pas sage of wire through the apparatus causing rotation of the grooved wheel and the associated second guiding means such that inherent twists in the low tension end of the wire pass through the apparatus to the high tension end of the wire.

Alternatively, the first embodiment may be simplified for use with one particular size of drum in which case the apparatus includes a hollow axle carrying a pulley attached to and rotatable with the axle, the grooved wheel being attached to the axle at a position adjacent the pulley and rotatable with the axle, the wheel having mounted thereon the second guiding means for directing the wire from the grooved wheel to the high tension end of the apparatus, the enforced passage of wire through the apparatus causing rotation of the grooved wheel and the associated second guiding means such that inherent twists in the low tension end of the wire pass through the apparatus to the high tension end of the wire.

In a second embodiment of the invention, the grooved wheel rotates in two planes at right angles to one another and is attached to a central spindle one end of which is fitted with a pinion engaging with a fixed crown wheel, the enforced passage of wire through the apparatus trans mitting the resultant rotational motion of the grooved Wheel about its axis of revolution to the pinion Which in turn produces further rotation of the grooved wheel about an axis parallel to the central axis of the crown Wheel such that inherent twists in the low tension end of the wire pass through the apparatus to the high tension end of the wire.

By way of example only, apparatus embodyingthe invention will now be described in greater detail with reference to the accompanying drawings of which:

FIG. 1 is a first perspective view of a first embodiment,

FIG. 2 is a second perspective view of a first embodiment, and

FIG. 3 is a perspective view of a second embodiment.

Referring to FIGS. 1 and 2 showing a first embodiment of the invention, the apparatus includes a hollow axle 3 having a first pulley 2 attached to one end of the axle and a second pulley 1 free to rotate on the axle and positioned towards the other end thereof. The pulleys 2 and 1 are coupled together via belts 4, 5 and a variable speed gear 6. At the other end of the axle 3 and adjacent the second pulley 1 is a grooved wheel in the form of a sheave 7 fixed to the axle and rotatable therewith. A guide tube 10 and a bracket 13 carrying two idler pulleys 8, 9 angled as shown in FIGS. 1 and 2 are rigidly attached to the second pulley 1. The apparatus is loaded for operation by threading the wire 12 through the guide tube 10, into and around the wire-gripping V-groove of the sheave 7, over the idler pulleys 8, 9 and into and through the hollow axle 3.

In the actual cable-laying operation, the high tension end of the wire is attached to a sinker and the wire is drawn out of the drums on the cable-laying ship as the ship moves away from the sinker. With the previously mentioned arrangement in which a continuous length of wire is drawn off without rotation of the drums, the tendency is for the inherent twists formed in the wire on drawing off from the drums to build up immediately outside the drums and cause kinks or snarls due to the relative- 1y low tension in the wire at that point. These kinks or snarls can be avoided by transferring the inherent twists in the wire from this region of low tension to a region of high tension and this is achieved by inserting the apparatus shown in FIGS. 1 and 2 in the path of the wire after leaving the drum.

When the wire is pulled through the device after having been threaded therethrough as detailed above, the friction between the wire and the V-groove of the sleeve 7 (which friction permits no slipping of the wire in the groove) causes rotation of the sheave 7. Consequently the axle 3 and fixed pulley 2 rotate, the rotation of the pulley 2 being transferred via belt 5, gear 6 (whose purpose will be described in more detail later) and belt 4 to pulley 1 and the associated guide tube and idler pulley arrangement. This rotation of pulley 1 and more particularly of the idler pulley arrangement transfers the inherent twists in the wire through the apparatus to the high tension side of the device where kinks or snarls are unable to form due to the tension in the wire. This tension on the load side of the device is controlled by means of a brake assembly 11 which is shown in the diagrams to act on the pulley 1 but which may equally well be adapted, for example, to control the rotation of the axle 3 or the rotation of either the fixed pulley 2 or the sheave 7.

There is a specific number of twists to be transferred per unit length of wire, this number depending upon the average diameter of the coils of wire in the drums. For one particular size of drum, it is possible to lock the pulley 1 either on the axle 3 or to the sheave 7 and exclude from the aparatus the variable speed gear 6, pulley 2 and belts 5, 4. Then, as the wire is pulled through the device, the sheave 7 and pulley 1 together with the associated idler pulleys 8, 9 rotate as one and in unison with the hollow axle 3 resulting in the transfer of each inherent twist from the low tension side of the device to the high tension side.

However, by unlocking the pulley 1 and introducing the variable speed gear 6 which couples this pulley 1 to the sheave 7 via the pulley 2 and belts 5, 4, the gear 6 may be varied as required to suit different numbers of twists per unit length of wire, which number will depend upon the average diameters of the drums of precoiled wire.

A second embodiment of the invention is shown in FIG. 3 which provides alternative apparatus for transferring inherent twists in a wire from a region of low tens1on to one of high tension.

A grooved sheave is attached to and rotatable with a central spindle 21, to one end of which spindle is keyed a pinion 22 engaging with a fixed crown-wheel 24 as shown, The other end of the pindle 2; may carry an idler pinion 23 alsoengaging with the crown-wheel 24. The spindle 21 is mounted in a box-section framework 25 by means of

bearings

26, 27, the sheave 20 being so positioned in the framework that it can rotate freely therein. Two

hollow stub axles

28, 29 are fastened, one to each end of the framework to rotate in fixed bearings 30, 31 and the apparatus is completed by a disc brake 32 keyed to the axle 29.

The apparatus is loaded for use in transferring inherent twists in a wire from a region of low tension to one of high tension by threading the wire 33 through the hollow axle 28, into and through a first guide-tube (not shown), into and around part of the wire gripping V- groove of the sheave 20, into and through a second guide-tube (not shown) and out through the hollow axle 29. Contact of the wire with the sheave 20 preferably occurs over -300 of lap.

When the wire is pulled through the device, the contact of the wire with the sheave 20 causes rotation of the sheave and spindle 21 within the framework 25, and this rotation of the spindle is transmitted to the pinion 22 which co-operates with the fixed crown-wheel 24 to produce rotation of the whole framework 25 together with the sheave 20 and spindle 21 in .the vertical plane in which the crown-wheel 24 is fixed. This bodily rotation of the sheave 20 and framework 25 transfers the inherent twists in the wire 33 from the low tension drawing-off side to the high tension load side of the device. The disc brake 32 keyed to the stub axle 29 controls the tension of the wire on the load side of the apparatus.

I claim:

1. Apparatus for transferring inherent twists in a wire comprising in combination first wire guiding means and second wire guiding means, and located between said first and second we're guiding means, a grooved wheel to which the wire is guided by the first guiding means, a rotatably mounted shaft, said grooved wheel being fixed to said shaft for rotation therewith, a driving pulley fixed to said shaft for rotation therewith, a driven pulley freely rotatable on the shaft, a drive transmission interconnecting said driving and driven pulleys, a mounting on said driven pulley, and a wire twisting mechanism fixed to said mounting for twisting the wire about its longitudinal axis as the wire moves from the wheel to the second wire guiding means.

2. Apparatus as claimed in claim 1 which said wire twisting mechanism comprises first and second idler pulleys, said first idler pulley guiding wire from said grooved wheel to said second idler pulley, and .means for supporting said second idler pulley on said mounting for rotation about its own axis and for rotation, when said driven pulley rotates, about an axis which is tangential to said second idler pulley and parallel to the axis of and lying within said hollow shaft.

3. Apparatus as claimed in claim 1 in which said drive transmission includes a variable speed gear.

4. Apparatus as claimed in claim 1 and further comprising a brake mounted upon said driven pulley for controlling the speed of rotation thereof.

5. Apparatus for transferring inherent twists in a wire from a low tension side of the apparatus to a high tension side thereof comprising in combination a first wire guide, a rotatably-mounted grooved wheel, the first guide leading the wire on the low tension side to the groove of the grooved wheel, a wire twisting mechanism for twisting the wire about its longitudinal axis as it passes through the second wire guide, and drive transmission transmitting the rotary movement of the grooved wheel to the wire twisting mechanism to rotate the latter.

6. Apparatus as claimed in claim 5 in which said mechanism comprises a framework, mountings enabling the framework to rotate about a longitudinal axis, bearings on said framework for rotatably mounting said grooved wheel about an axis normal to said longitudinal axis and intersecting m said first and second wire guides lying on said longitudinal axis to guide the Wire therealong.

References Cited UNITED STATES PATENTS Arkerna et a1 242128 Fuller 242-128 Ash 5759 Dessureau et a1 140149 6 8/1967 Barry et a1. 242-128 3/1968 Lemaire 140149 US. Cl. X.R.