Patent Publication Number: US-6698722-B1

Title: Apparatus and method for use in handling a load

Description:
This is a continuation of application Ser. No. 09/274,259, filed Mar. 22, 1999, now U.S. Pat. No. 6,267,356. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to apparatus for use in handling a load which is capable of raising and lowering, or of towing, a load and also handling service cables and/or hoses connected to the load. The invention is particularly, but not exclusively, applicable to the handling of subsea equipment such as grabs. 
     Hitherto, providing services to underwater equipment has required the provision of a specific bundle of cable(s) and/or hose(s) dedicated to each application. For some applications, it is known to incorporate the service bundle within an armored hoist rope. This approach has a number of deficiencies. The resulting rope is costly, gives inferior hoisting properties, and by virtue of limitations on the diameter of rope which can be handled the services which can be incorporated are limited. Further, in practice it is impossible with this arrangement to add to the length of the rope or to join different types of materials, for example wire ropes with fiber ropes. 
     It is also known from our previous application PCT/GB96/00158 to wrap service cable around a rope being paid out, and to unwrap the service cable from the rope as the rope is recovered. 
     BRIEF SUMMARY OF THE INVENTION 
     According to the present invention there is provided apparatus for use in handling a load comprising a load-bearing rope, a mechanism for paying out and recovering the rope, a first service cable holder for holding a first service cable with a length of the first service cable extending therefrom, a second service cable holder for holding a second service cable with a length of the second service cable extending therefrom, and a wrapping device for rotating said lengths of service cable around the rope as the rope is payed out to wrap the service cables around the rope, wherein one of the first and second service cables is wrapped over the other. 
     The service cable holders can be drums. 
     Typically the wrapping device can recover the service cables to their respective drums during recovery of the rope and cables. 
     The term “service cable” is used herein to denote a flexible elongate member used for conveying power or data, such as an electrical cable, a fiber optic cable, or a pneumatic or hydraulic hose. 
     Preferably, the service cables are wrapped helically around the rope. 
     Typically, the load-bearing rope will be a hoist rope used for raising and lowering a load. Alternatively, the load-bearing rope may be a towing rope used for paying out, towing and recovering a load such as a marine sensor array. 
     Preferably, the mechanism for paying out and recovering the rope comprises a rope winch, from which the rope passes over a rope sheave and thereafter extends to the load along a substantially straight axis. 
     The wrapping device may comprise the or each service cable drum being arranged for rotation about a drum axis which coincides with said axis, the drum typically having a central aperture through which the load-bearing rope passes, said length of service cable preferably passing over a service cable sheave which is mounted for movement in a circular path around said axis. 
     Alternatively, the or each service cable drum may be rotatable on a structural member which is arranged for movement in a circular path about said axis. 
     The hoist rope winch, the or each service cable drum, and the wrapping device may conveniently each have a respective driving motor; they could however be driven by a single source through appropriate mechanical linkages. 
     The first and second cables are typically wrapped around the rope in different directions; for example, the first cable can be wrapped onto the rope in an anticlockwise direction and the second cable can be wrapped around the rope in a clockwise direction so that one cable overlays the other. This option is to be preferred but the invention can also work well with the service cables being wrapped in the same direction but at different pitches of helix, so that one overwraps the other. 
     The invention also provides apparatus for use in handling a load comprises a load-bearing rope, a mechanism for paying out and recovering the rope, a mechanism for holding and paying out a service cable and a wrapping device for rotating one of the service cable and the rope around the other as they are payed out to wrap the said one of the service cable and the rope around the other, and to unwrap one of the service cable and the rope from the other as it is recovered, wherein at least part of the wrapping device can be moved to accommodate large objects. 
     In a preferred embodiment the service cable is provided on drum which is mounted on an arm which rotates around the axis of the rope. The drum can be arranged to rotate about a horizontal or a vertical axis. 
     The service cable holder is preferably mounted on an arm that is preferably hinged to a frame and can be provided with a lifting mechanism such as a hydraulic ram to lift the arm with respect to the frame. Instead of a hydraulic ram the lifting mechanism may be a screw-driven mechanism which can be electrically or hydraulically powered. 
     The invention also provides apparatus for use in handling a load comprising a load-bearing rope, a mechanism for paying out and recovering the rope, a drum for holding a service cable with a length of the service cable extending therefrom, and a wrapping device for rotating said length of service cable around the rope as the rope is payed out to wrap the service cable around the rope, and to unwrap the service cable from the rope as the rope is recovered, wherein the wrapping device rotates around the axis of the rope, but does not rotate about its own axis. 
     The invention also provides apparatus for use in handling a load comprising a load-bearing rope, a mechanism for paying out and recovering the rope, a cable holder for holding a service cable with a length of the service cable extending therefrom, and a wrapping device for rotating said length of service cable around the rope as the rope is payed out to wrap the service cable around the rope, and having at least one slot to facilitate attachment of the apparatus to the load-bearing rope. 
     The invention also provides a method for use in handling a load, the method, comprising paying out a load-bearing rope and wrapping first and second service cables around the rope as it is payed out, and subsequently unwrapping the service cable from the rope as the rope is recovered, wherein one of the service cables is wrapped over the other. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Examples of apparatus and a method for use in handling a load in accordance with the invention will now be described with reference to the drawings, in which: 
     FIG. 1 is a schematic perspective view illustrating the principle of operation of a first winding device; 
     FIG. 2 is a more detailed side view, partly in section, of an apparatus used in the example of FIG. 1; 
     FIG. 3 is a view similar to FIG. 1 illustrating a modification of the arrangement of FIG. 1; 
     FIG. 4 is a schematic perspective view illustrating a second example; 
     FIG. 5 is a side view of an apparatus used in the example of FIG. 4; 
     FIG. 6 is a schematic perspective view illustrating a third example similar to that of FIG. 1 but modified for towing rather than lifting; 
     FIG. 7 illustrates a fourth example similar to that of FIG. 4 but modified for towing rather than lifting; 
     FIG. 8 a  is a schematic side view of a fifth embodiment; 
     FIG. 8 b  is a close up view of the FIG. 8 a  embodiment; 
     FIG. 8 c  shows in side sectional view some of the components of the fifth embodiment; 
     FIG. 8 d  shows a further component of the fifth embodiment; 
     FIG. 9 a  shows a side sectional view of an arm assembly of the fifth embodiment; 
     FIG. 9 b  shows a side sectional view of a further arm assembly of the fifth embodiment; 
     FIGS. 10 a  and  10   b  show a side and top view respectively of a sixth embodiment; 
     FIG. 11 shows a side view of a sleeve and bearing of the sixth embodiment; 
     FIG. 12 shows a plan view of a main support plate of the sixth embodiment; 
     FIGS. 13 a  and  13   b  show plan views of bearings used in the sixth embodiment; 
     FIGS. 14 a ,  14   b  and  14   c  show plan views of gears used in the sixth embodiment; 
     FIGS. 15 a ,  15   b  and  15   c  show plan views of further gears used in the sixth embodiment; 
     FIG. 16 shows an exploded side view of the drive train in the sixth embodiment; 
     FIG. 17 shows a side view of a gearbox of the sixth embodiment; 
     FIG. 18 shows a seventh embodiment of a cable winding device; 
     FIG. 19 shows an eighth embodiment of a cable winding device; 
     FIG. 20 shows a ninth embodiment of a cable winding device; 
     FIG. 21 shows a further embodiment of a winding device; 
     FIG. 22 shows a further device similar to the FIG. 3 device; and 
     FIG. 23 shows a further embodiment of a winding device. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1 and 2 show an optional mechanical linkage in the form of belt B linking the shaft of the rope winch  13  to a spur gear S on the rope sheave  4 . A motor M drives the rope winch  13  and transmits power via the mechanical linkages of the belt B and spur gear S to the motor  7 . The motor  7  can optionally be linked to the motor  6  so that the rope winch motor M can be used to drive the winch, service cable drum and the rotation of the service cable sheave  5  to wrap the service cable  2  around the rope  1 . 
     Referring to FIG. 1, a hoist rope  1  extends from a hoist rope winch  13  over a hoist rope sheave  4  to support a load (not shown) for raising and lowering. The hoist rope  1  may be any suitable form of hoist rope such as flexible steel wire rope or synthetic fiber rope, for example of “KEVLAR®”. KEVLAR(® is a registered trademark of E. I. du Pont de Nemours and Company, which is a Delaware corporation having a place of business at 1007 Market Street, Wilmington, Del. 19898. A service cable  2  is reeled on a service cable drum  3  and extends to the load via a service cable sheave  5 . 
     The hoist rope  1  passes through a central aperture of the service cable drum  3 , and the service cable sheave  5  is arranged to be driven circumferentially around the axis of the service cable  1 . By coordinating the movements of the hoist rope winch  13 , the service cable drum  3  and the service cable sheave  5 , the service cable  2  can be wrapped helically around the hoist rope  1  as the load is lowered, and unwrapped as the load is raised. In this way, a hoist rope of any desired properties can be used in combination with any required service connection. 
     Further, service cables on other drums can be added to be rotated by a motor in different directions. 
     FIG. 2 shows the service cable drum  3  and associated parts in greater detail. The hoist rope sheave  4  is journalled to a fixed frame  20  which is secured to any suitable supporting structure (not shown). The service cable drum  3  is rotatably mounted on the lower part of the frame  20  and driven in rotation by a motor  6 . 
     The inner end of the service cable  2  is connected to the appropriate service by a coupling assembly  8  which includes a slip ring arrangement in the case of electrical or fiber optic services or a rotary coupling in the case of pneumatic or hydraulic services; such rotary couplings are well known per se. 
     The service cable sheave  5  is joumalled on a mounting frame  9  which is rotatable about the fixed frame  20  by means of a motor  7 . 
     The service cable  2  shown in this embodiment may be a single cable or hose, or may be a specially made cable comprising a plurality of cable(s)/hose(s). 
     The motors  6  and  7  are driven at speeds related to the axial speed of the hoist rope  1 . The speed correlation may be fixed. Preferably, however, this correlation will be controllable to alter both the length of twist (pitch) of the lay of the service cable  2  on the hoist rope  1 , and the tension in the service cable  2 . 
     FIG. 3 shows a modification in which a second service cable  17  is wrapped on the hoist rope  1  along with the service cable  2 . In this modification, the service cables  2 ,  17  are each provided with a respective storage drum  15 ,  16  and a respective sheave  5 ,  14 , e.g., drum, which may suitably be carried on a common supporting frame for rotation in unison. The drum  14  revolves in an opposite direction to the drum  5  around the rope&#39;s axis, so that the second service cable  17  is wrapped around the hoist rope  1  in the opposite direction to that of the service cable  2 . 
     The apparatus may be further modified by adding further drums and sheaves to handle more services. At least one service cable is overwrapped on the others, and this is preferably the last one to be applied so that the overwrapping cable is at the outer surface of the wrapped assembly. 
     FIG. 4 illustrates a second example in which the service cable  2  is reeled on a service cable drum  3  and the service cable drum  3  is itself rotated about the hoist rope  1  to achieve a helical wrap and unwrap. As shown in more detail in FIG. 5, the service cable drum  3  may be constituted by a drum  12  removably mounted on a hub motor  11  which is carried on the end of an arm  18  rotatably mounted on the fixed frame  20  and driven by a motor  10 . 
     As with the first example, the example shown in FIGS. 4 and 5 could be modified by adding further service cable drums to be rotated by the motor  10  in the opposite direction to the first cable and drum so as to overwrap the second cable on top of the first. 
     FIG. 6 illustrates the example of FIG. 1 modified for use in a marine towing application, for example in paying out, towing and recovering a sensor array such as a sonar sensor or seismographic surveying sensor, the sensor array being towed underwater or on the surface. The service cable drum  3  is hinged to the main structure of the towing vessel (not shown) and can be tilted to a desired towing angle by hydraulic or other mechanisms. Likewise, FIG. 7 illustrates the modification of the example of FIG. 4 for the same use, the frame carrying the mounting arm for the service cable drum  3  being hinged to the vessel and tilted to the desired angle by hydraulic or other mechanisms. 
     The invention may be applied to a system in which one or more service cables is applied to a load-bearing rope which itself carries a service channel in addition to fulfilling its load-bearing function. For example, the load-bearing rope could be a steel wire rope carrying electrical signals, or a rope comprising KEVLAR® load-bearing strands in combination with optical fiber cable. 
     FIG. 8 discloses a further embodiment of the invention having first and second drums  31  and  32  which are arranged to rotate around a load-bearing rope  35  in different directions and can wind different cables (for example a fiber optic communications cable and a high voltage power cable) in opposite directions around the central load-bearing rope  35 . This has been found by the inventor to be useful particularly in applications where the load-bearing rope  35  remains slack during certain periods in the operation of the equipment. By contra-rotating the cables around the load-bearing rope they are less likely to move or become loose should the load-bearing rope  35  slacken. In addition, a fragile cable such as a fiber optic cable wound around the load-bearing rope  35  in a first direction can be overlaid by e.g., a high voltage power cable wound around the load-bearing rope  35  and fiber optic cable in the opposite direction, and this can also afford some protection to fragile cables such as fiber optics etc. 
     In the FIG. 8 apparatus, two different cables wound onto the respective drums  31  and  32  are paid out while the drums are rotated around the load-bearing rope  35 . 
     The drum  31  is mounted on an arm  40  connected to an arm assembly  41  having a top hat structure with a top surface, and an annular flange  41   f  provided at the lower end of side walls  41   s  (shown in FIG. 9 a ). The arm assembly  41  has a central aperture  42  in its top surface through which the load-bearing rope  35  passes, and has an annular bevel gear  43  cut into the outer edge of its top surface. 
     The second drum  32  is supported on a further arm  50  also connected to an arm assembly  51  having a similar top hat structure and shown in FIG. 9 b . Arm assembly  51  comprises a lower annular flange  51   f  with a sleeve  51   s  attached thereto and having a central bore  51   b  extending through the sleeve  51   s  and through the annular flange  51   f . A bevel gear  53  (shown in FIG. 9 a ) is manufactured separately but located over the sleeve  51   s  and fixed in place by any suitable means, for example by welding or bolting or other fixing means after the apparatus has been assembled. 
     The FIG. 8 apparatus is assembled by locating the arm assembly  41  and a pair of bearing rings  44  over the sleeve  51   s , so that the arm assembly  41  is capable of rotating on the bearings around the sleeve  51   s . A slip ring  55  for transmitting electric or hydraulic power via the rotating arm assembly  41  and arm  40  to the drum  31  is then located over the ring  41  to rest on the flange  41   f . Slip rings suitable for this and other purposes of the invention are known and suitable electrical, fiber optic and fluid rotary union slip rings are available, e.g., from Focal Technologies Inc. of 40 Thornhill Drive, Unit 7 Dartmouth, Nova Scotia, Canada B 3 B  1 S 1 . Such slip rings for electrical, fiber optic and hydraulic power transmission are clearly readily available and will not be described further here. 
     The bevel gear  53  is then offered to the sleeve  51   s  and attached thereto in opposite orientation to bevel gear  43 . A further slip ring  56  is located on top of the bevel gear  53  in order to transmit power from a stationary source via the sleeve  51   s , flange  51   f  and arm  50  to the drum  32 . 
     Bearing rings  45  are then located over the sleeve  51   s  and a support bracket  58  is placed around them and attached to the ship or other structure from which the apparatus is to be used. The support bracket  58  likewise has an annular flange  58   f  and an aperture  58   a  for the sleeve  51   s . A top ring  60  having a central aperture for the through passage of the rope  35  is then bolted to the upper face of the sleeve  51   s , and secures the annular apparatus together around the central sleeve  51   s.    
     On the flange  58   f  of the support bracket  58 , a motor  62  drives a shaft  63  to a gearbox  64  disposed below the support bracket  58  but above the lower slip ring  55 . The motor  62  and the gearbox  64  transmit power via shaft  65  between the slip rings to a bevel gear drivehead  66 . The bevel drivehead  66  engages the bevel gears  53  and  43  and drives them in opposite directions simultaneously. By a single force exerted from the motor  62 , the arms  40  and  50  and therefore the drums  31  and  32  can thus be driven in opposite contra-rotating directions around the central axis of the load-bearing rope  35  as it is payed out (described previously). 
     The bearings  44 ,  45  support the arm assemblies  41  and  51  so that they can rotate within the main support bracket  58  attached to the ship or other structure. 
     The winch drums  31  and  32  can hoist and lower cables by use of electric or hydraulic power transmitted through the slip rings  55 ,  56 . Conventional power cables (or hydraulic conduits if hydraulic motors are used) can be passed through the drum support arms  40  and  50  from the inner half of the slip ring adapters which will remain stationary in relation to the arms  40 ,  50 . 
     Although the embodiment shown in FIGS. 8 &amp; 9 is driven through the motor  62  and the bevel drivehead  66 , the apparatus could also be driven from the sleeve  51   s  which could in certain embodiments protrude out of the securing plate and be rotated using belts, gears, chains or similar mechanisms. The bevel gear arrangement shown in FIGS. 8 &amp; 9 would in that embodiment still remain to contra-rotate the drums under the power applied to the sleeve  51   s  and therefore the bevel gear  53 . 
     The drums  31 ,  32  could also be driven independently using two separate motors. One motor at the top of the sleeve  51   s  as mentioned above could drive the arm  50 , and the motor  62  could drive the arm assembly  41  through the bevel drivehead  66 . That embodiment would not require the additional bevel gear  53 , which could be removed. 
     A further improved variant of the invention is shown in the remaining FIGS. 10 to  17 . Components of the mechanism shown in these figures are slotted so that the apparatus can be deployed or recovered without first having to pass the load-bearing rope through the center of the mechanism. The load-bearing rope can instead be removed or replaced within the mechanism during any part of the operation. This is particularly useful with heavy and oversized pieces of equipment. The slots can be filled by removable segments which are replaced after the load-bearing rope has been located within the mechanism. This has the advantage of allowing more traditional slip rings and the segment could be located easily within a tapered notch. Single gear driving would then be possible, but it is also equally possible to drive a slotted mechanism by two or more gears as shown in the drawings and described below. The embodiment shown and described is not affected by the notches, and these allow the load-bearing rope to be removed or placed within the mechanism as required without removal of the notch filling segment. More than one drive shaft is preferable to reduce the possibility of contact being lost with the center drive when the notch thereon passes the driving wheel. In the embodiments shown, all of the parts which rotate around the load-bearing rope  35  are slotted. 
     Referring now to FIGS. 10 to  17 , a central rotating notched sleeve  151 , having an annular flange  151   f  on its outer surface is provided. The sleeve  151  is notched at  115  to allow radial passage of the rope  35  through the notch  115  into the axial bore. An annular thrust bearing  170  separates the lower surface of the flange  151   f  from a main support plate  175  through which it passes via a central aperture  175   a , also notched. The main support plate  175  also has two side apertures  175   b  and  175   c  through which the drive shafts of motors  176  and  177  pass. 
     A main support bearing  179  surrounds the outer surface of the sleeve  151  above the flange  151   f.    
     The motor  176  drives winding gear  180  which is used to drive the winding of the rope around the central load-bearing rope  35 . Winding gear  180  is a circular gear driving two further gears  181 ,  182  in the same direction. Gear train  180 ,  181 ,  182  drives a spur gear  185  also having a notch  115  coinciding with the notch  115  in the sleeve  151  , and keyed to the sleeve  151  by means of a keyway  185   k . Rotation of the gear train  180 ,  181 ,  182  therefore drives the spur gear  185  and (by virtue of the keyway) the sleeve  151 . Since the gears  181  and  182  are spaced apart, the notching of the assembly of the spur gear  185  and the sleeve  151  does not affect power transmission to the sleeve  151 , since even if the notch  115  is adjacent one of the gears  181 ,  182 , the other will still be contacting the teeth and will transmit power to the sleeve  151  for the time taken for the notch  115  to pass the gear  181  or  182  as the case may be. 
     A drum  190  is carried on a support arm  191  attached to the lower end of the sleeve  151  and therefore rotation of the drive train  180 ,  181 ,  182  by the motor  176  drives rotation of the arm  191  around the central axis of the load-bearing rope, thereby winding the cable on the drum  190  axially around the load-bearing rope  35  as it is payed out as described previously. 
     Hoist and payout of the cable on the drum  190  is driven by the motor  177  through the drive train to be described below. Motor  177  has a driveshaft  177   d  passing through the aperture  175   c  in the main support plate  175 . A spacer  178  spaces a gear  200  driven by the shaft  177   d  from the lower surface of the main support plate  175 . Gear  200  is part of a drive train  200 ,  201 ,  202  similar to the drive train  180 ,  181 ,  182  as previously described. Drive train  200 ,  201 ,  202  drives the rotation of a notched spur gear  205  having a notch  115  and located around the sleeve  151  on a bearing  203 . The spur gear  205  is able to rotate relative to the sleeve  151 , and is driven around the sleeve by the operation of the drive train  200 ,  201 ,  202 . The drive train  200 ,  201 ,  202  meshes with an upper row of teeth  206  on the gear  205 . Spur gear  205  also carries a lower row  207  of teeth which are clearly also driven in rotation by operation of the drive train  200 ,  201 ,  202 . A further set of gears  210 ,  211 ,  212  mesh in a fashion similar to that described for the gears  180 ,  181 ,  182  with the lower teeth  207  of the spur gear  205 . The gear  210  is located on a drive shaft connected to a right angled gearbox  215  where a bevel gear or similar arrangement drives rotation of a perpendicular second shaft  216 , which through a pulley wheel drives the rotation of the drum  190  around its own axis by a belt, chain or similar such means. This allows the motor to hoist in or lower the power or signal cable on the drum. The gear box  215  is mounted on the drum support arm  191 , which is held in place by a notched securing nut  220 . 
     The securing, e.g., locating C, nut  220  secures the winch support arm, the double row toothed gear  205  the single row toothed gear and two shims, which all slide up onto the lower half of the central rotating notched cylinder  17 . 
     More than one drum can be provided on the embodiment described, and where two drums are provided, they can be rotated in opposite directions. 
     The central rotating notched cylinder is held in position by the thrust bearing and the main support bearing within which it can rotate freely. 
     The main support plate is attached to the ship or other structure and provides the support for the motors and the bearing housings for the main support bearing and thrust bearing. 
     All components preferably have a notch cut in them to allow the load-bearing rope to be swung into the mechanism. By use of the motor to rotate the winch drum around the load-bearing rope the central rotating notch can be lined up with the notch in the bearings and the main support plate. Using the motor to rotate the gear its notch can also be aligned and the load-bearing rope can either be placed within the mechanism or removed from it. 
     The teeth on the gears  180 ,  181 ,  182 , etc. can be replaced by a pulley system such as that shown in FIG. 14 c  which uses a notched belt  185   b  running on gears  180 ′,  181 ′,  182 ′ driving gear  185 ′. 
     The motors used for driving any of the presently described embodiments can be of any suitable type. Conventional motors available for many years are eminently suitable, and any standard electric or hydraulic motors available for over 15 years by any of the manufacturers Charlin, Eaton, White, Mannesmann-Rexroth, Hawker Sidley and many others are suitable. Various different kinds of motors available for the winch and frame driving motors etc. will be well known to one of moderate skill in the art. 
     FIG. 18 shows a further device having a first drum  350   u  arranged above a second lower drum  350   l , both of which are arranged around a load-bearing rope  1  which passes through their axes. The drums  350  each have a respective arm  359   u / 359   l  and spooling gear  360   u / 360   l  which spools off the cables in the upper and lower drums in different directions and can wind different cables (for example a fiber optic communications cable on the upper drum  350   u  and a high voltage power cable on the lower drum  350   l ) in opposite directions around the central load-bearing rope  1  in the same manner as the embodiment described with regard to FIGS. 8 and 9. 
     In the FIG. 18 apparatus, two different cables wound onto respective drums  350   u  and  350   l  are paid out while the arms  359   u / 359   l  rotate around the load-bearing rope  1 . 
     Drums  350   u  have a top hat structure with a pair of annular flanges provided at the lower end of side walls. The cable is stored between the annular flanges, and the side walls define a cylinder through which the hoist rope  1  can pass axially. The arms  359  are each mounted on a sleeve with an annular bevel gear cut into an opposing edge to allow a single bevel drivehead  360  to drive each of the arms in opposite directions. The same or a different bevel drivehead can be used for each. Bevel drivehead  360  engages beveled edges on the arms  350  and drives them in opposite directions simultaneously. By a single force exerted from a motor (not shown), the arms can thus be driven in opposite contra-rotating directions around the central axis of the load-bearing rope  1  as it is payed out. 
     The drums are hung on a frame  320  which holds bearings and slip rings as previously described. 
     Although the embodiment shown in FIG. 18 is driven through a motor and the bevel drivehead  360 , the apparatus could also be driven from a sleeve forming part of an arm or a drum and which could in certain embodiments protrude out of the assembly and be rotated using belts, gears, chains or similar mechanisms. The bevel gear arrangement shown in FIG. 18 could in that embodiment still remain to contra-rotate the arms under the power applied to the sleeve and therefore bevel gear  360 . 
     The arms could also be driven independently using two separate motors. 
     FIG. 19 shows a further cable winding device which has a trough  5   t  rather than a service cable sheath, e.g., drum  5  for storing the service cable  2 . This is very useful for very thick or heavy cables not suitable for storage on the drum  5 . The trough  5   t  is provided with spooling gear in the form of sheaves and can optionally incorporate tensioning devices such as a linear winch e.g. a pair of tires though which the cable can run and which retard the cable thereby tensioning it slightly. A further trough can be added to provide another service cable to be wrapped around the rope in the opposite direction to that of the first cable. 
     FIG. 20 shows a further cable winding device which dispenses with the need for slip rings. The FIG. 20 device is suitable for cables which will withstand a twist every turn or a pre-twisting of the cable before it is run onto the drum. The turns per meters of the cable paid out will be dependent on the diameter of the cable on the cable winch. 
     In the FIG. 20 device the signal/power service cable can be wound from a power supply or other service connection (not shown) via several guide sheaves onto a first drum  5   s  of small diameter. The small diameter drum  5   s  can be located on an upper part of the winch drum which can either be turned by a motor, or can remain stationary with an arm revolving to unwrap the cable from it. The purpose of the small diameter drum is to allow limited movement on the main drum as the hoist rope may twist thereby requiring more turns of the signal/power cable drum than were originally put onto the hoist rope as it was paid out. 
     The service cable  2  is typically paid out from the main cable winch drum  5  by a rotating arm  9   a  rotating in a direction which unwinds the cable  2  from the drum  5 . The rotating arm  9   a  rotates in the opposite direction to wind on the cable  2 . The arm  9   a  can be set to pay out at a preset tension and hoist if the tension is less than that preset tension. 
     In the FIG. 20 device, the service cable  2  is connected to the service (power signal etc.) and wound first onto the small drum  5   s . An aperture in the small drum wall allows the service cable  2  to pass into the axial bore of the drum  5  where it runs parallel to the rope  1  to the level of the main lower drum  51 . It passes through the wall of the main drum  51  and onto the spool from which it is unwound by the spooling gear on the rotating arm  9   a  in much the same manner as has been described previously. The cable can be applied to the drum  5  with a pre-twist so as to avoid kinking in the cable during use. 
     Further signal cables can be applied to the rope using the FIG. 20 device. 
     In other embodiments the cable drum can be arranged to rotate around the rope and/or can rotate on its own horizontal axis in order that the rope can be spooled off in a similar manner to other embodiments. 
     FIG. 21 illustrates a further embodiment in which the service cable  2  is reeled on a drum  3  and the drum  3  is itself rotated about the hoist rope  1  to achieve a helical wrap and unwrap. The service cable drum  3  may be constituted by a drum  12  removably mounted on a hub motor  11  which is carried on the end of an arm  18  rotatably mounted on a fixed frame  20  and driven by a motor  10 . The arm  18  has a hinge  18   h  connecting it to the frame  20  and a hydraulic ram  18   r  to pivot the arm  18  about the hinge  18   h  relative to the frame  20  from the lower position shown in FIG. 2 to the higher position, so as to move the cable drum  3  out of the way of large loads being lifted by the hoist rope  1 . 
     Further service cable drums could be added to be rotated by the motor  10 . 
     FIG. 22 shows a further embodiment similar to the FIG. 2 embodiment in which the service cable drum  3  is rotatably mounted on the lower part of the frame  20  with the rope  1  passing through an axial aperture in the service cable drum  3  and driven in rotation by a motor  6 . The arm of the mounting frame  9  has a hinge  9   h  and a hydraulic ram  9   r  connecting two shoulders on opposite sides of the hinge  9   h . The ram can be activated to draw the sheave-bearing part of the arm  9  upwards out of the way of large objects being lifted. 
     FIG. 23 shows a further embodiment in which the service cable  2  is held on a drum  5   a  which is fixed to an arm  30  that can rotate about the axis of the rope  1 . The drum  5   a  does not need to be rotatably mounted on the arm  30  so that it rotates on its own axis but instead has a further arm  31  that rotates about the axis of the drum  5 a and carries the cable via spooling gear  32  to the rope  1 . 
     The drum  5   a  may have a tapered surface and this provides another aspect of the invention. 
     Other modifications may be made within the scope of the invention.