WO1987003552A1

WO1987003552A1 - Method and device for hauling in and veering out a rope on board a ship in connection with fishing or the like

Info

Publication number: WO1987003552A1
Application number: PCT/DK1986/000133
Authority: WO
Inventors: Aage No^/rskov LAURSEN; Richardt B. Nissen; So^/ren Flyvholm RO^/NN
Original assignee: Laursen Aage Noerskov
Priority date: 1985-12-16
Filing date: 1986-12-16
Publication date: 1987-06-18
Also published as: AU6777287A; EP0252103A1

Abstract

By a method for hauling in and veering out a rope (2) on board a ship (34) in connection with fishing, the rope (2) with its one end is connected to a junction on a fishing net, a trawl, a seine, a sea-going detection sonde or the like tool or commodity, which after veering out is desired to haul in and/or to draw behind the ship via the rope, and the other end of the rope (2) is fastened to a drum (6), around which the winding up takes place during hauling in, and winding off takes place during veering out. The rope (2) between the tool and the depot drum (6) is taken around at least one V-grooved pulley set, and the rope tension between the V-grooved pulley set and the drum (6) at least during hauling in is kept essentially constant at a value between 0.5 and 5 kN, preferably 2-3 kN, for holding taut, and the rope (2) between the grooved pulley set and the drum (6) during standstill or during veering out is kept essentially at a constant rope tension of between 0 and 5 kN, preferably 1 kN, by controlling the torque of the drum (6) independently of its number of revolutions. Thereby is obtained that hauling in of fishing nets may take place free of twitches at a high constant hauling in force.

Description

Method and device for hauling in and veering out a rope on board a ship in connection with fishing or the like.

The present invention concerns a method and a device for hauling in and veering out of a rope or a wire on board a ship in connection with fishing whereby the rope at its one end is connected to a junction on a fishing net, trawl, seine, a sea-going detection sonde or the like appliance or tool for via the rope after veering out thereof to be drawn after the ship or/and to be hauled in on the ship, and whereby the second end of the rope is fastened to a drum, on which the rope is would up during hauling in and on which the unwinding takes place during the veering out.

On board ships it is known to haul in ropes by utilizing a capstan with a capstan head where the rope is wound a number of times around the capstan head and therefrom is taken to a rope depot drum which pulls in the rope and causing that the rope is tightened firmly around the capstan head. It is also known th haul in a rope directly on a rope or wire drum without using a capstan head between gunwale rollers and guiding rollers which guide the rope to the rope drum.

It is a drawback by using such capstan head that by its rotation it receives the rope at its one end of its ligation, i.e. its concave rotat onal surface, and de¬ li ers rope from the second end of its ligation, where- by the rope gradually winds up along the one inclining end of the capstan head until the inclination has reach¬ ed such size that the rope momentarily slides downwards to the centre of the capstan head where the diameter is smaller. Thereby a considerable wear and tear of the rope and noise emission occur due to a continuous series of bumps whereby also water and sand from the rope is thrown all over the deck. Each time the rope momentarily slides along the capstan head, the rope is veered out a Little, whereupon it is tightened around the capstan head in a new position so that the hauling in may be started again. Consequently, the hauling in is postponed as part of tne rope due to the mentioned veering out during its momentary slidings is actually hauled in several times. Where more ropes with this method are hauled in si ultaneously and are desired to be hauled in synchronously one more di sac- vantage occurs, viz. that the two ropes do not slide to the same extent on the capstan head during their mo- mentary slidings. Thereby longitudinal displacements or hauling in differences between the two or more ropes occur which then accumulate so that the longitudinal displacements or differences between the ropes now and then are to be adjusted.

The drawbacks by hauling in by means of a single rope drum directly without using a capstan head are partly the increasing hauling in torque to be performed by the drum, so that the torque of the drum should be dimen¬ sioned in accordance with the largest winding up diame- ter which can occur on the drum. Furthermore, the rope is wound up on the drum in several layers and often the necessary pull will cause the rope of the upper rope layers to wedge down into the underlying rope lay¬ ers. The rope is worn and damaged both during its wedging into the underlying rope layers and during its being pulled out during its veering out. In the above text as well as in the following a rope should mean as well ordinary ropes used on the sea and made from natu¬ ral or artific al fibres, and wires of steel or wires of stell and natural and/or artificial fibres.

In case two or more ropes at the same time are hauled in on respec ive drums also longitudinal displacements or differences in rope lengths will occur which diffe- rences will accumulate if the pull is uneven, and the ropes will wedge to different extents down into the underlying rope layers.

It is the purpose of this invention to eliminate the above drawbacks. Said purpose is ac ieved by a method in which each rope between the tool and a depot drum according to the invention being taken around at^' least one V-grooved pulley set and that the rope tension between the V-grooved pulley set and the drum at least during the hauling in is kept essentially constantly at a value between 0.5 and 5 kN, preferably 2-3 kN, for taut holding, and that the rope between the V- grooved pulley set and the drum during standstill or during veering out is kept at an essentially constant tension of between 0 and 5 kN, preferably 1 kN, by con- trolling the torque of the drum independently of the number of revolutions thereof.

Thereby the above disadvantages are eliminated seeing that the wear and tear is considerably reduced because the rope is always tightened and oes not slide^'. In case more than one rope are pulled synchronously by means of respective V-grooved pulley sets and depot drums, frequent rope length adjustments are not neces¬ sary. No bumps, noise or waste of time will occur, seeing that the hauling in takes place smoothly and constantly according to the number of revolutions of the V-grooved pulley sets. By a V-grooved pulley set should be meant a construction comprising two driving shafts each having at least one V-grooved pulley being secured thereto in a torsion-.proof way, said pulley having at least one V-formed rope groove wherein a single rope has been laid around the grooved pulleys for hauling in and veering out opera¬ tions and where the two driving shafts which are arrang¬ ed in a mutual distance are driven rotatably in the same direction synchronously by the same or respective motors. A V-grooved pulley winch may comprise one or more V- grooved pulley sets driven by the same or separate power units in the V-grooved pulley winch.

In case the method is used for hauling in seines, nets or other appliances by means of more cooperating ropes, each rope is advantageously hauled in with respective V-grooved pulley sets and corresponding depot drums for the rope, and the number of rope threads or runs in the V-grooved pulley set is so adapted that the pull or the winding up tension after the last thread or run by the largest dimensioned pull in the rope to the appliance becomes so small that it is no more than just able to secure a correct winding up of the rope on the depot drum. Thereby an embodiment is obtained being well suited for the handling of more ropes cooperating on same fishing net or other tool having several rope connections and being adapted for^'being conveyed or pulled through water behind a ship.

With the present invention one obviously has overcome a prejudice in the fishing against the use of V-grooved pulley winches for hauling in fishing nets. In this occupation the theory has existed that the hard bumps from the capstan heads were transmitted in the ropes to the sea floor and that the noise and the cloud of

-s sand or mud thereby caused chased the fish from the sea floor and gathered them in front .of the net. The results from fishing with V-grooved pulley winches of the invention now show that said theory is all wrong, seeing that the fishing yield is not lower by V-grooved pulley winches than by capstan head arrangements. Furthermore, prejudices have presumably been based on the new and unknown features by V-formed grooves in¬ stead of capstan heads where the rope threads on a V-grooved pulley set cause high tensions and implies high rope speeds so that in the rope parts between the V-grooved pulleys of the V-grooved pulley set great forces occur which attempt to draw the driving shafts of the V-grooved pulley set in a direction towards each other. An advantage by the method according to the invention is that each capstan head of existing capstan head arrangements immediately may be replaced by a V-grooved pulley set, viz. that a capstan head capstan also immediately may be replaced by a V-grooved pul ley winch .

Ecisting arrangements with drum winches may be adapted to the method thereby that V-grooved pulley winches with a V-grooved pulley set for each drum is arranged in front of the respective drum, whereby said existing arrangements may be used for fishing with larger nets thanks to the constantly great tension force of the V- grooved pulley set. The known trawl drum is now used only as tautholding drum and should only perform a rope tension or pulling force in the rope of 0.5-3 kN against earlier 100-200 kN pulling force by empty drum and consequently with a very much reduced pulling abi¬ lity available when the drum is full.

A possible hauling in rope difference at the start between two ropes being hauled in by means of respective V- grooved pulley sets and depot drums will advantageous¬ ly be adjusted essentially to zero by decreasing the pulling force in the rope between the one depot drum and the V-grooved pulley set thereof, viz. to decrease the torque of the depot drum until the adjustment has been made.

In case a V-grooved pulley set separately for each rope is used, a rope length adjustment may also be made by rotating the one or the other V-grooved pulley set in a direction opposite to the other set, while the depot drums are adapted for hauling in at a relati ely low pulling force, e.g. 1 kN, w ich will be easily overcome by the veering out forces of the grooved pulley sets when veering out takes place.

The invention will now be described in more detail by way of example and with reference to the accompanying schematic drawings wherein

Fig. 1 shows in plane view a prior art seine winch where- by the rope parts are handled by respective cap¬ stan heads with corresponding depot drums, fig. 2 shows in plane view a prior art trawl winch whereby the ropes of the net are hauled in by respective rope drums, fig. 3 shows in plane view a socalled split winch where¬ by the ropes of the net are hauled in by separa¬ te, separately driven rope drums, fig. 4 shows in plane view a double V-grooved pulley winch for the method according to the invention whereby the rope parts of the net are handled by respective V-grooved pulley sets with respective depot drums. fig. 5 shows in plane view the detail of fig. 4 with a single V-grooved pulley winch for each rope part of the net, fig. 6 shows in plane view the single V-grooved pulley winches of fig. 5 here being replaced by V-grooved pulley winches where- each mu It i-V-grooved pulley in each V-grooved pulley set is driven by its hydraulic motor, fig. 7 shows a pressing roller arrangement, fig. 8 shows a grooved pulley set according to the inven¬ tion and a depot drum arranged below on board a ship, fig. 9 shows a grooved pulley winch arranged all below on board a ship, and fig. 10 shows a grooved pulley winch with two V-grooved pulley sets and corresponding depot drums arrang¬ ed midship.

From Danish Patent No. 133,224, cf. fig. 1 of the present application it is known to haul in seine ropes 2 by using a winch with two capstan heads 4 for hauling in respective seine ropes 2, as said seine rope 2 is wound more times around the capstan head 4 and is taken to a depot drum 6 which is pulling in the rope and causes that the rope is tightened firmly around the capstan head 4. The rope 2 passes from the seine and in front of the capstan heads 4 respecti e ^' gunwa le rollers 8, and after the capstan heads the respective depot drum 6 has guiding rollers 10 and spooling guide rollers 12.

It is also known - as shown in Fig. 2 - to let the ropes 2 of the net pass respective gallow blocks 14 before the rope after passing the spooling guide rollers 12 is wound up on respective rope drums 6 which ' ia couplings 16 are driven by the same motor or transmis¬ sion 18. The items of Fig_ 3 differ from the items of fig. 2 only thereby that the two rope drums are driven by their respective motor or transmission not shown. Said arrangement is known as split winch, enabling indepen- dent stop and start if an adjustment between the rope lengths should turn out desirable.

By the arrangement of fig. Λ , when a capstan head is rotating and delivering rope 2 from its one end of the Ligation to the rope drum 6, the rope 2 will simulta- neously be received and wound up at the other end of the Ligation, so that the rope 2 gradually will wind up along the inclined end of the capstan head 4 until the inclination reaches such a size that the. rope 2 mo¬ mentarily slides downwards to the cylindrical centre of the capstan head having a smaller diameter. In the period of time where the rope 2 momentarily slides on the capstan head 4, the seine net not shown via the ropes 2 will draw said ropes backwards, i.e. away from the ship, and thereupon will tighten the ropes around the capstan heads in a new position so that the hauling in may start again.

If one rope is a little more loaded than the other, a simultaneous rope length displacement will take place which then will accumulate into an increasing rope length difference.

Said principle of working provides much wear and tear and much noise due to a series of bumping or shock movements which also cause that water and possible sand from the rope is thrown widely around. The hauling in is postponed because a certain part of the rope length d splacements shall be adjusted from time to time.

By ordinary iftrawl winches, cf. fig. 2, and split winches. cf. fig. 3, the hauling in of the rope 2 takes place on constantly increasing winding up diameter on the rope drums 6 as the trawl wires or the ropes are wound upon respective drums 6. The increasing winding up dia- meter on the drums 6 demands an increasing hauling in torque on the drum axes.

This demands a greater power available which in turn by hydraulic devices demands larger hydraulic pumps and pipes and more expensive installation, also in order to fulfill the demand for high rope speed when the rope winding diameter on the drum is small.

The rope is wound on the drum 6 in many layers in the arrangements of figs. 2 and 3, and the necessary tension of several kN cause the outer rope threads to wedge into the underlying threads or layers. The rope is worn and damaged no matter which material it is made from, both during wedging and being pulled out from the rope layers .

All said drawbacks by the devices of figs. 1-3 are eli- minated by the method according to the invention.

Fig. 4 shows a double V-grooved pulley winch for carry¬ ing out the method according to the invention in an arrangement corresponding to the one shown in Fig. 1. The winch comprises a V-grooved pulley set consisting of two mu It i-V-grooved pulleys 20 on each side, and the seine ropes 2 are wound back and forth over the mul- ti-V-grooved pulleys, all of which are motor driven. In this embodiment all muIti-V-grooved pulleys are driven by the same power supply means, e.g. a hydraulic motor.

The two separate units in Figs. 5 and 6 may as shown be 10

arranged in a mutual distance, but this, however, does not exclude that they may be arranged closely to one another, clamped together or bui lt together in a common unit. For floating trawl and other purposes it may be desirable to let four or more separate units work to¬ gether. By seining it may be desirable to cooperate with one or two small wire drums on respective hydrau¬ lic motors .

The use of said modifications depends on the demands for pulling force, rope length adjustments and the possibility of a rapid rope movement stop by the diffe¬ rent kinds of fishing.

The arrangements of figs. 5 and 6 will be very suitable for trawl fishing on medium and very big ships and by arrangements for use for more kinds of fishing, but all three types may be used for Danish seine, flyshooting and trawl fishing.

In Fig. 4 the rope length adjustment of the ropes 2 may be made by stopping the hauling in en one side of the depot drums 6, viz. the drum in which the rope 2 has been too much hauled in, until the difference in rope length has been set off. In the meantime the ulti- V-grooved pulley 20 slides below the relieved rope 2. Said solution puts certain demands- on the power supplied to the depot drums 6 when they must be able to stop and start rapidly with a heavy wound-up rope weight.

By Figs. 5 and 6 the rope Length adjustment of the ropes 2 may be made by rotating the one or the other V-grooved pulley set of the winch in one direction or the other, while the depot drums 6 always are adjusted for hauling in at a relatively low pulling force which is easily 1 1

overcome by the veering out force of the V-grooved pulley sets when veering out is to be made.

By Danish and Scottish seining the V-grooved pulley sets are used for hauling in but not for veering out, seeing that the."ropes 2 are put out one at a time di r_ect- ly from the rope drums 6. By trawl fishing the ropes are veered out by means of the V-grooved pulley sets.

By the embodiment of Fig. 6 whereby each of the two ul- ti-V-grooved pulleys 20 is driven by its respective hydraulic motor, a double veering out speed can be obtained in each V-grooved pulley set by coupling to¬ gether the motors 26 in series instead of parallel with a given hydraulic pump capacity. During hauling in on the contrary they are coupled parallelly when the full pulling force is needed.

Like in case of split winches each V-grooved pulley set may be driven by respective pumps or by the same pump as the one driving another V-grooved pulley set in a balanced system. Thereby the advantages and possibili- ties may be obtained which are well known from working with and controlling of split winches.

Usually a higher pulling force is used for hauling in of trawl in trawl fishing than for hauling in the seine in seining .

By providing the V-grooved pulley sets with easily re¬ placeable mult i-V-grooved pulleys, mu Iti-V-grooved pulleys of smaller diameters for grawl fishing and of larger diameter for seining may be used whereby one V-grooved polley set may be used with different V-grooved pulley diameters, but still a suitable pulling force for the fishing in question may be obtained. Thereby a separate V-grooved pulley winch or trawl winch with a pipe installation on deck may be saved, when the ship is to be equipped to carry out both kinds of fishing, solely due to said easy replaceabi li- ty with multi-V-grooved pulleys of different diameters. By using V-grooved pulley winches and depot drums 6^" instead of the trawl winch arrangements of figs. 2 and 3 the constant hauling in diameter is taken advantage of, viz. that a constant torque on the multi-V-grooved pulleys is to be performed.

As a consequence of the depot drums 6 by the method according to the invention only serving to keep the rope 2 tight between the V-grooved pulley set and the respective trum 6, the rope is not brutally laced up, but is wound on the depot drums 6 with only the most necessary tightening which causes a considerably in¬ creased lifetime for the ropes.

The depot drums 6 may be arranged below somewhere at a free space on the ship 34. Due to the small pulling force in the. rope between the V-grooved pulley set and its respective depot drum it causes no problems to guide the rope 2 to the Location where the arrangement of the drum 6 is most advantageous in consideration of space and weight displacement influence on the stabi lity of the stip 34. Said arrangement protects the equipment against wind and weather, and often useful deck space is made available in this way. Figs. 8 and 9 show examples of such arrangements.

In case the rope is made by a stiff trawl wire it might be necessary to mount contact rollers 28 preventing the rope 2 from jumping from one groove to the other in a multi-V-grooved pulley 20. Fig. 7 shows an example of such safety device w ere two spring Loaded contact rollers 28 along the V-grooved pulleys 20 are kept in a suitable distance from the V-grooved pulleys 20 but are able to yield when a thick splice on the rope is 5 to pass thereon.

Fig. 10 shows an arrangement of a V-grooved pulley winch 30 midship to Danish seine. Here the two seine ropes 2 of which just one is shown, must be able to be hauled in from starboard side shown with a dotted line, or

10 port side, shown with a full line, dependent on the fishing, and nevertheless taken to the depot drum belong¬ ing to the V-grooved pulley set in question. V-grooved winches and depot drums may stand separately as shown or be built together as a unit whereby less deck space

15 is required as well as shorter piping arrangement and a better possibility of finishing from the factory.

Figs. 5 and 6 show a shaft end spacing beam 32 w th a guard plate on the V-grooved pulleys 20, the outer free shaft ends of which are pivotably supported in the beam

20 32 which thus connects the two free shaft ends on the V-grooved pulley set. Thereby the V-grooved pulley set may resist an even greater lacing force from the rope 2. Preferably, such a beam 32 with bearings is easily removable for servicing of the V-grooved pulleys 20,

25 but as the beam 32 has no shoring, or connection to the deck, the ropes will always freely be wound on and off the desired number of V-grooves in the V-grooved pulleys

Claims

C l a i m s :

1. Method of hauling in and veering out a rope (2) on board a ship (34) in connection with fishing, where the rope (2) with one end is connected to a junction on a fishing net, a trawl, a seine, a sea-going detec- tion sonde or the like tool or appliance for via the rope (2) after veering out thereof to be hauled in and/ or drawn after the skip (34), and where the other end of the rope (2) is fastened to a drum (6), on which the rope is wound up during hauling in and the unwinding takes place during the veering out, c h a r a c t e r ¬ i z e d in that the rope (2) between the tool and the depot drum (6) is taken around at least one V-grooved pulley set, and that the rope tension between the V- grooved pulley set and the drum (6) at least during the hauling in is kept essentially constant at a value of between 0.5 and 5 kN, preferably 2-3 kN, for holding taut, and that the rope (2) between the V-grooved pulley set and the drum (6) during standsti ll or during veering out is kept at an essentially constant rope tension of between 0 and 5 kN, preferably about 1,0 kN, by control¬ ling the torque of the drum (6) independently of its number of revolutions.

2. Method according to claim 1 for hauling in of seines, nets and other tools by means of more cooperating ropes (2), c h a r a c t e r i z e d in that each rope (2) is hauled in with its separate V-grooved pulley set and corresponding depot drum (6) for the rope (2) and that the number of rope threads in each V-grooved pulley set s so adapted that the pull or the winding up tension after the last thread at the largestly dimensioned pull in the rope (2) for the tool becomes so small that it is no more but just able to secure a correct winding up of the rope (2) on the depot drum (6).

3. Method according to claims 1 or 2, c h a r a c t e ¬ r i z e d in that a hauling in difference between two ropes (2) being hauled in by means of respective V- grooved pulley sets and depot drums (6) is adjusted essentially to zero by decreasing the pulling force in the most hauled in rope (2) between the depot drum (6) and the V-grooved pulley set thereof, viz. to de¬ crease the torque of the depot drum (6) until adjustment has been made.

4. Method according to claims 1, 2 or 3, c h a r a c - t e r i z e d in that the veering out takes place by retaining the tension between the V-grooved pulley set and its depot drum (6) simultaneously with reversing the rotation direction of the V-grooved pulley set.

5. Method according to claims 1, 2, 3 or 4, c h a - r a c t e r i z e d in that two of the driving shafts of the V-grooved pulley set, each carrying one or more torsion-proof V-grooved pulleys (20), have their free ends kept in mutual distance by a pressing force therebetween being transmitted via a strut or compres¬ sing member (32) in which both aforesaid free ends are rotatably mounted in radial pressure bearings.

6. Device for hauling in and veering out a rope (2) on board a ship (34) and for carrying out the method of claim 1 and comprising a depot drum (6) to the rope (2), and a friction winch for engagement with the rope (2), when the winding up tension thereof is higher than a predeterm ned minimum value for securing the friction engagement, c h a r a c t e r i z e d in that the friction winch is a hydrau I i ca I ly driven V-grooved pulley winch (30) comprising at least two, at the most four V-grooved pulley driving shafts or at least one. at the most four V-grooved pulley sets, and that the rope between the V-grooved pulleys is only taken as a maximum about 180 of the periphery of each V-grooved pulley and that the dev ce comprises means for keeping the torque of the depot drum (6) so low that the ten¬ sion in the rope (2) between the V-grooved pulley winch (30) and the respective drum (6) is kept below 5 kN, preferably below 1 kN.