GB2390350A - Sailing vessel having wind steering means - Google Patents

Abstract

A sailing vessel includes a sail, a winch 6 and a control line 7 connecting the sail to the winch 6. The winch 6 is mounted 11, 12 to the vessel in a manner which permits movement of the winch 6 relative to the vessel in response to wind force on the sail. Force transmitting means 14, 15, 16 translates movement of the winch mount 12 into movement of the helm 1 of the vessel. In use, the helm 1 is steered in a direction which opposes a change in direction of wind force on the sail so as to keep the vessel on course. Tensioning means 17, such as a shock cord, opposes tension in the control line 7 between the winch 6 and the sail and may be adjustable. The winch may move in a linear manner along runners 11 or it may rotate about a pivot point (82, Fig 13).

Description

Relating to wind steering of sailing vessels This invention relates to

wind steering of Sailing Vessels.

Over the years there have been many ideas which will steer sailing vessels automatically, either by wind, wind and water, hydraulics, or electric power. The earliest design was used for sailing downwind in the trade winds. It consisted of two headsails, both fitted to the forestay, one set to starboard and the other set to port, and both using a spinnaker pole to limp them in position. The jib sheets for both these sails were led back to blocks on either side of the cockpit, from there they were led to the opposite side of the boat, and then back to the tiller. If the boat veered to starboard, the wind force would increase on the port side sail, and decrease on the starboard sail. This imbalance would cause an increase in load on the port side jibsheet, a decrease on the starboard side jibsheet, and this in turn would steer the boat to port, and hence back on coarse. Conversely if the boat veered to port the wind force would increase on the starboard sail, decrease on the port sail, and the jib sheets would steer the boat to starboard, again bringing it back on coarse. This system was very successful and is the concept that inspired this invention.

Modern designs use an independent windvane, which turns or bends with the changing wind direction to alter the position of the helm. The earliest of these uses a windvane only, mounted at the stern of the boat. The windvane which is supported by a pivot (or hinge) along the lower edge, has a counterweight to keep it upright, is normally positioned with one edge pointing towards the wind. If the boat veers off course, the wind pushes on one side of the windvane, which causes the vane to rotate about the pivot, against the counterweight. Control lines attached to the windvane control the tiller to bring the vessel back on course. Once back on course, the vane is once again edge on to the wind, and the counterweight returns the vane to the upright position. Unfortunately this return system using a counterweight was not very effective, at best the operation was very sluggish, and at worst it did not work at all. It is now no longer produced, but the principal of using a wind vane as the wind direction indicator is used by almost all, later designs.

1 he next significant design uses the windvane to twist a paddle, which hangs in the water behind the boat, and the water moving past the paddle makes it swing to port or starboard. This movement is transmitted to the tiller using control ropes. The design by H. G. Hasler, and used by Sir Alec Rose on his round the world voyage is described here.

The servo blade, (or paddle) S (Figure 2) resembles a dinghy's rudder, and hangs vertically over the stern. It is carried on bearings inside the servo box (F), and can be fumed like a rudder by means of the servo tiller (A). T he servo box (F) is itself carried on fore-and-aft bearings (E) which are mounted on the portable tubular bumkin (B), so that the box (F) can swing from side to side like a pendulum, taking the blade (S) with it. A servo quadrant (P) is integral with the box (F), and steering ropes (W) (Figure 2) lead from it through steering sheaves (C) to the rudderhead quadrant (Q), which is secured to the top of the tiller. The plywood wind-vane (V) is connected to its linkage through the latch gear (L), which enables the desired course to be selected.

It also enables the vane to be unlatched in an emergency by pulling on a latch line which is led to the cockpit, thus permitting instant reversion to manual steering while

the vane 'weathercocks'. When the latch (L) is connected, any turning movement of the vane (V) is transmitted via the reversing linkage and the servo tiller (A) to the servo blade (S). Please note that Figs. 1 and 2 are purely diagrammatic, and do not attempt to show the true proportions or layout of the components. To set a course, the vane is first unclutched at (L) and the yacht steered manually on to the correct course while the vane weather-cocks. The vane is then clutched in at (L), and the tiller is allowed to swing freely. Fig. 2 shows the vane set for running before the wind, and it will be seen that if the yacht now yaws to starboard, the change in direction of the apparent wind will cause the vane (V) to turn anti-clockwise, when looking down on it. This movement causes the servo blade (S) to turn clockwise. The flow of water past it (caused by the forward motion of the yacht through the water) makes it swing sideways to starboard, as shown by the right-hand arrow (D), thus pulling on the starboard steering rope which turns the main rudder to bring the yacht back on course.

A slight variation of the Haslar design is manufactured by a company called Navik, who are based in France. Here the rotation of the paddle is not controlled directly by the windvane, but by a small control rudder attached to the trailing edge of the paddle.

Here the windvane steers the control rudder, which in turn causes the paddle to rotate.

A further variation on this design is where the control rudder is attached to the trailing edge of the main rudder. This is achieved in two different ways according to the mounting position of the rudder. For a transom hung rudder, the control rudder is attached directly to the trailing edge of the main rudder, by hinges. For a rudder which is mounted further forward, the control rudder which is positioned astern of the vessel is attached using an extension bracket from the rudder to the control rudder. Both these systems use a windvane to control and operate the control rudder One design, manufactured by Hydrovane has abandoned any direct control of the main rudder, but uses its own auxiliary rudder which is positioned astern of the vessel, and is controlled and operated by its own wind vane. This is a successful design and is currently available. Although it is a very heavy construction its manufacturers claim it can operate better than the pendulum system by virtue of the fact that it can operate in much lighter winds. The design is reminiscent of the earliest design where the windvane controls the rudder directly, and I wonder if the operation could be rather sluggish. Another recent attempt has been to use a small additional sail to operate the helm through blocks and lines. I understand that currently there has been no success with this system.

very different design manufactured by an American Company, called Windhunter, uses a propeller towed behind the boat, which drives a hydraulic pump. This pump drives a hydraulic ram, which is attached to the tiller, and this steers the boat.

Operation of the hydraulic ram is by means of a servo valve, which is controlled by a windvane in the same way as the Haslar design.

The electric systems use a linear motor driven by the ships' battery. This type of steering system can be set to follow a compass course, or using a small wind-vane, will follow a course relative to the wind direction. These are small and compact units

currently manufactured by Autohelm and Navico. They work using a small electric motor housed inside the unit, which rotates a threaded shaft. This shaft attached to the unit body at one end, sits inside a threaded sleeve, which is attached to the tiller at its exposed end. The rotating screw thread moves the sleeve in and out, and with the body of the unit attached to one side of the cockpit, the unit steers the boat. The unit also houses a fluxgate compass, and a control circuit.

The main disadvantage of the wind and water systems is that they are rather expensive, large, heavy, vulnerable to damage in storms and crowded harbours, and clutter up the stern where a number of items are normally kept, such as lifebelts, boarding ladders, and aerials. I he design using the towed propeller is a neater design, and it can also be used to charge the ships battery, its main disadvantage is that the towed propeller will slow the boat down. The electric units by contrast are much smaller, lighter, cheaper, and easier to install. Their main disadvantage however, is that they consume electricity. This is a valuable commodity on a sailing vessel, particularly for small leisure craft where there are a minimum number of batteries and the only generator is the small alternator fitted to the engine. Also, as the strength of wind increases, the electric systems use more electric power, putting an even greater strain on the batteries, which should be reserved for navigation lights, and starting the engine in an emergency. Another disadvantage of the electrical systems is they have a limited life. Although perfectly adequate for coastal sailing, these units are prone to failure on longer transcontinental voyages, as has been experienced by single handed yachtsmen during round the world races. It is normal for these sailors to wear out two or three of these units during a race.

This invention is powered by the wind, but does not suffer from vulnerable and heavy components used by existing designs. All the components are compact, relatively low cost, rugged, and are sited inboard.

The main concept is to use the wind force in the foresail to detect wind changes through pressure in the sail, and transmit this energy directly to the helm. This is achieved by mounting the foresail winch on a moving platform. The changing pressure in the foresail is transmitted to the winch via the jibsheet (foresail control line), and a 'spring tensioner' reacting against the jibsheet tension, to keep it in position. Any imbalance caused by the changing pressure on the foresail is transmitted by mechanical means to operate the helm, and bring the vessel back on course.

The invention will now be described by way of some examples Figure 3 shows a plan view of the cockpit section of a sailing vessel. The port side (left hand) has been omitted for clarity. Items which are standard equipment on a sailing vessel are: (1) the tiller which controls the rudder via the rudder shaft (2), (3) is the starboard (right) seat, (4) is the forward end of the cockpit, and (5) is the aft end of the cockpit. The mainsheet (line which controls the mainsail) is not shown. The winch (6), which must be self tailing, controls the foresail using the jibsheet (7). The starboard gunwale (right edge) of the vessel is shown as (8), the cockpit coarning (edge) is shown as (9), and forms the back of the cockpit seat. Finally, the winch platform is shown as the area (10), on top of the cockpit coaming.

Items which are not standard equipment in a sailing vessel and relate to this invention are: runners (l I), sliding winch base (12) which is free running on runners (1 1), using linear bearings (13), primary drive arm (14), drive pivot arm (21) which is pivoted about point (15), secondary drive arm (16), spring tensioner (17) which is made from shockcord (elasticated rope), and blocks (18), and (19). Block (18) is attached to sliding winch base (12), and block (19) is attached to the aft end of winch platform (lO). The shockcord runs through blocks (18), and (19), in a typical block and tackle arrangement, and passes under, and well clear of pivot arm (21). The tail end is tied offto a cleat (not shown). Primary drive arm (14) is attached to sliding winch base (12) at one end, and pivot arm (21), at point y, at the other. Secondary drive arm (16) is attached to pivot arm (21), at point x, at one end, and the tiller (1), at the other.

Attachment of the secondary drive arm to the pivot arm at 'x', and attachment ofthe secondary drive arm to the tiller, is made using a typical spinnaker pole quick release mechanism. This attachment is also used in the designs described in Figures 7, and l 2 Theory of operation: For normal manual sailing, the mainsail, and foresails are set in the correct position to suit the direction and strength of the wind for sailing in the desired direction. An example of this is shown in Figure 4. Here for a particular setting of sails, the wind is in direction YV. As the wind alters direction, relative to the direction of the yacht, the pressure of air changes on the sails. If the wind direction moves towards the stern (back of the vessel), i.e. from direction XX, then the wind pressure on the sails increases, and if the wind direction moves towards the bows (front of the vessel), i.e. direction ZZ then the wind pressure on the sails decreases.

The aim of the helmsman is to keep on course relative to the wind. He will steer the vessel up wind if the wind moves towards the stern, and downwind if the wind moves towards the bows.

This invention duplicates this activity, by using the pressure of wind in the foresail.

Please note. These examples assume that the wind is coming from the port (left) side only. When the wind comes from the starboard (right) side, the sails and a jibsheet (7) is set to the port side. The whole assembly described here is mirrored on the port side and will operate in a similar manner to the method described below.

Referring to the diagram in Figure 3. For any particular setting of the sails, the tension force in the jibsheet (7) is balanced by the tension force in the spring tensioner (17).

Fine adjustments are made by hauling, or slackening the tail end of the shockcord, and attaching to a cleat (not shown).

As the wind moves towards the stern from the balanced position, i.e. from direction YY to direction XX, the tension in the jibsheet (7), increases. This pulls against the spring tensioner (17) causing the sliding platform (12), and winch (6) to move forward on runners (11) using linear bearings (13). This action turns the pivot arm (21) clockwise via primary drive arm (14). This turning motion also causes the tiller (1) to

turn clockwise via secondary drive arm (16), together with the rudder via the rudder shaft (2), as shown in the diagram in Figure 5, steering the vessel up wind. Once the rudder has returned the vessel back on course, the excess pressure is no longer on the sails, the tension is reduced in the jibsheet (7), and the excess tension in the spring tensioner (17), returns the tiller to its central position using the reverse motion of the assembly. Conversely, as the wind moves towards the bows, i.e. from direction YY to direction ZZ, from the balanced position, the pressure in the sails decreases, tension in the jibsheet is reduced, and the spring tensioner pulls the sliding platform, and winch back on the runners. This motion turns the pivot arm anticlockwise using the primary drive arm, and consequently turns the tiller anticlockwise via the secondary drive arm, which turns the rudder, steering the vessel down wind, as shown in Figure 6. Once the vessel is back on course, the increased pressure in the sails increases tension in the jibsheet, and consequently returns the tiller to the central position.

Spring tensioner design considerations.

1. The tension in the spring tensioner (17) should be fairly constant through the whole of its stroke. This is achieved by positioning the blocks (18), and (19) some distance from each other. This ensures the actual stroke is a small compared with the potential stroke and small compared with the distance between blocks (18) and (19). Hence the difference in load at the start and end of the stroke is small, and the velocity of the tiller is therefore kept fairly even from the start to the end of its movement. A wide variation in tension would cause a tailing off in tiller speed towards the end of the stroke, which would have the effect of creating sluggishness in returning the vessel to the correct course.

2. When a sailing vessel sails against the wind, i.e. tacking, the tension in the jib sheet, and the turning force required to turn the rudder can be very high.

Conversely, when the sailing vessel is sailing with the wind, i.e. downwind, the tension in the jib sheet, and the force required to turn the rudder, is very small. This large variation must be catered for in the design of the spring tensioner. An example of how this achieved is shown in Figure 17. Here the block (19) is a double block, and the item, which up to now has been described as block (l 8) consists of two single blocks which are attached to the sliding platform (12) at point (22) using a quick release shackle (snap shackle). Tension in the shock cord (25) is adjusted using the tail end of the shock cord and cleating it off using cleat (23). When the tension becomes too light to cause too little movement of the sliding plattorrn, one of the blocks (18) can be moved to a keeper position (24) as shown. The tension is now halved. The variation in loading can be increased further by using a triple block at (19), three single blocks at (18), with a smaller diameter shock cord.

When the vessel is sailing downwind (with the wind coming from astern), the foresail is flown goose-winged, i.e. it is positioned on the opposite side of the boat to the mainsail, so that it is not masked from the wind. With the sails set in this way, the action of the self steering must act in the opposite way to normal in order to keep the vessel on course. This is achieved as follows:

Referring to the diagram in Figure 7, here a sailing vessel is shown in plan view. The foresail (90) is set on the starboard side, and the mainsail (91) is set on the port side.

The secondary drive arm (16) is removed, and a conko1 line (92) is attached to the pivot arm (21) in its place. The control line passes round block (93) on the port side and back to the tiller at point (94). Shock cord (95) is also attached to the tiller at th same point (94) and the other end it is attached to the starboard side of the cockpit at point (96). The shock cord, and control line are both set taught, and react against each other. The whole rig is initially set with the wind coming from direction 'PP'. If the wind alters course to 'QQ' pressure in the foresail increases causing the pivot arm to rotate clockwise (as described earlier). This pulls the control line, causing the tiller to rotate anticlockwise and thus steering the vessel to starboard and back on course with the wind. If the wind alters course to 'RR' the pressure in the foresail is reduced, causing the pivot arm to rotate anticlockwise. This removes the tension in the control line allowing the tension in the shock cord to turn the tiller in a clockwise direction thus steering the vessel to port, and back on course with the wind.

It is also possible to sail in this direction with the mainsail set to the starboard side, and the foresail set to the port side. In this situation, the self-steering works using the port side mechanism, and with the control line and shock cord reversed.

A second example of this invention is where the force transmitted to the secondary drive arm (16) is via pulleys and cables. Referring to the diagram in Figure 8, which shows the same plan view of the cockpit described in Figure 3, but with a different arrangement method for transmitting the steering force to the tiller.

Here, pulley large (26), and small pulley (27) are attached to each other so they rotate as one, on a vertical axis. They are mounted on a sliding platform (28), which in turn is mounted on runners (11). Wire (29) is attached, at one end, to the aft end of platform (12). It passes around pulley (26) in a clockwise direction, passes under platform (12), around pulley (30) and back to platform (]2) where it is attached to its forward end via a spring tensioning device (31) (not shown). A large fixed pulley (32) is mounted on platform (10) and can rotate freely about a vertical axis. Wire (33) passes around pulleys (27), and (32) in a continuous loop. Primary drive arm (34) is fixed to pulley (32) at one end, and is attached to secondary drive arm (16) at the other through a hinged arrangement Because pulleys (26), and (27) are mounted on a sliding platform, the spring tensioner (31) retains tension in wires (29) and (33) .

The method of operation differs from the previous example in that the change in tension in the jib sheet is transmitted to the tiller in the following way. The movement of sliding platform (12) moves the wire (29), which rotates the pulley (26). This rotates pulley (27) by the same amount to cause wire (33) to move. Wire (33) rotates pulley (32) and primary drive arm (34), which in turn rotates the tiller (1) via secondary drive arm (16). Figure 9 shows the arrangement with an increase in tension of the jib sheet, and Figure 10 shows the arrangement with a decrease in tension in the

jib sheet. The pulley arrangement here is designed to give a large rotational movement of arm (34), from a small movement of winch platform (12). This is quite important because any large movement of winch (6) will alter the setting of the foresail. This is also true for all variations of this invention.

The arrangement described in Figure 8 can also be used for yachts with wheel steering. The following is an example of how this can be achieved.

Figure 11 shows a complete plan view of the cockpit of a sailing vessel with wheel steering. Items, which are standard equipment, on this type of vessel are steering pedestal (34), steering wheel (35), and cockpit seats (3). (4) is the forward end ofthe cockpit, and (5) is the aft end of the cockpit. Winches (6) and (36), which again must be self tailing, control the jibshcets (7) and (37) respectively, the gunwales are shown as (8), the cockpit coamings are shown as (9), and the winch platforms are shown as areas (10) and (38).

Items which are not standard items and relate to this example of the invention are: runners (11) and (39), sliding winch bases (12) and (40) which are free running on their respective runners (I 1) and (39), using linear bearings (13). Tension in the jibsheet is balanced by tension in spring tensioners (17) and (61). On the port side, pulley (41), and pulley (42) which are attached to each other and rotate on a vertical axis are mounted on sliding platform (43) which is free running (using linear bearings) on runners (39). Wire (44) is attached at one end to the aft end of platform (40), passes around pulley (41) in an anticlockwise direction, passes under platform (40), around pulley (45), and back to platform (40) where it is attached to its forward end via a spring tensioning device (46) (not shown). A double grooved fixed pulley (47) is mounted on platform (3 8) and can freely rotate about a vertical axis. Wire (48) passes around pulley (42) and the lower groove in pulley (47) in a continuous loop.

On the starboard side, pulley (49), and pulley (50) which are attached to each other and rotate on a vertical axis are mounted on sliding platform (51) which is free running, using linear bearings (13), on runners (11). Wire (52) is attached at one end to the aft end of platform (12), passes around pulley (49) in an clockwise direction, passes under platform ( 12), around pulley (53), and back to platform (12) where it is attached to its forward end using a spring tensioning device (54) (not shown). A double grooved fixed pulley (55) is mounted on platform (10) and can freely rotate about a vertical axis. Wire (56) passes around pulley (50) and the lower groove on pulley (55) in a continuous loop. Wire (57) passes across the cockpit around the upper grooves in pulleys (47) and (55) in a continuous loop, and the tension in this wire is kept constant using spring tensioner (58). The forward part of this loop is wrapped around grooves in clutch (59). Control lever (60) engages and disengages clutch (S9).

The assembly and operation of the clutch is shown in Figure 12. This diagram shows a front elevation, side elevation, plan view, sectional view at 'AA', and a view on arrow B'. Referring to this diagram, (62) is the main body, which is attached to the rudder drive shaft stub at (63), and the steering wheel at (64). A pulley (65) is mounted on the main body, and is allowed to spin freely on bearing (66). It is prevented from sliding of f by three retaining screws (67), which are screwed into the main body, and protrude into radial groove (68). The control wire (57) (see Figure 10) is wrapped around

g pulley (65) in groove (69). Driving wedge (70) is attached firmly to shaft (71), which in turn is attached firmly to head (72). The wedge (71) is held in the disengaged position in the main body with spring (73), which impinges on head (72), and this also holds control lever (74) in the out position, shown as position (75) on the catch plate (76). For manual steering, the clutch is set in the 'disengaged' position, as shown. To engage the self-steering gear, the control lever is moved into position (77) on the catch plate, which forces the driving wedge (70) into vee groove (78). This causes the pulley and main body to rotate together.

Referring back to Figure 11 when the wind is from the port side, the starboard jib sheet is used to control the foresail. With the jib sheet set, and the spring tensioner (17) adjusted to balance the load, any changes in wind direction will cause the starboard winch platform (12) to slide forward and backwards along runner's (11).

This movement is transmitted to clutch (59) via wire (52), pulley wheels (49), and (50), on through wire (56), to pulley (55), and then to wire (57). The movement will then be transmitted through the pulleys and wires on the port side, back to the port side sliding winch platform. It is important that the port side spring tensioner is disengaged when the starboard winch is in operation.

When the wind is from the starboard side, the port jib sheet is used to control the foresail. With the j ib sheet set, and the spring tensioner (6]) adjusted to balance the load, any changes in wind direction will cause the port winch platform (40) to slide forward and backwards along runners (11). This movement is transmitted to clutch (59) via wire (44), pulley wheels (41), and (42), on through wire (48), to pulley (47), and then to wire (57). The movement will then be transmitted through the pulleys and wires on the starboard side, back to the starboard side sliding winch platform. It is important that the starboard side spring tensioner is disengaged when the port winch is in operation.

The purpose of the intermediate pulley wheels (41), and (42), on the port side, plus the corresponding pulley wheels (49), and (50) on the starboard side, is to gear up the small sliding movement of the platforms (40), and (] 2) to create a sufficiently large movement of the rudder.

Please note, the wire (57) is shown passing directly across the cockpit. In practice, this would be fed down the side of the cockpit, along the cockpit sole (floor), and the part of the wire which wraps around the pulley (69), would be guided up the side of the steering pedestal (34) using guide pulleys. All the moving parts in this design except for the sliding winch platform and spring tensioners can be housed in protective guards. Another variation of this invention is where the sliding movement of platform 1 operates a hydraulic ram. This in turn will power a second ram to operate the rudder.

The design of the ram attached to the sliding platform will have a large diameter and a small movement, and the design of the ram attached to the rudder will have a small diameter and a large movement.

The fmal example relating to this invention is shown in figure 13. This diagram shows a plan view of the cockpit section of a sailing vessel. The port side (left hand) has been omitted for clarity. Items which are standard equipment on a sailing vessel are: (I) the tiller which controls the rudder via the rudder shaft (2), (3) is the starboard (right) seat, (4) is the forward end of the cockpit, and (5) is the aft end of the cockpit.

The mainsheet (line which control the mainsail) is not shown. The winch (6), which again, must be self tailing, controls the foresail using the jibsheet (7) (foresail control line). The starboard gunwale (right edge) of the vessel is shown as (8), the cockpit coaming (edge) is shown as (9), and forms the back of the cockpit seat, the winch platform is shown as the area (10), on top ofthe cockpit coaming. Items which are not standard equipment in a sailing vessel and relate to

this invention are: winch base (79) which rotates freely about pivot point (82) on a vertical axis, spring tensioner (] 7) which is made from shockcord (e]asticated rope), and blocks (18), and (l9). Block (18) is attached to rotating winch base (79), and block (19) is attached to the aft end of winch platform (10). The shockcord runs through the blocks ( 18), and (19), in a typical block and tackle arrangement, and passes under, and well clear of drive arms (80) and (81). Secondary drive arm (81) is attached to primary drive arm at point x, at one end, and the tiller (1), at the other.

As the wind moves towards the stern from this balanced position, the increased pressure in the foresail increases the load in the spring tensioner (17) causing the rotating platform (79), primary drive arm (80), and winch (6) to rotate anti-clockwise.

This action causes the tiller ( I) to turn clockwise, together with the rudder shaft (2) and the rudder, via secondary drive arm (81), as shown in the diagram in Figure 14, steering the vessel up wind. Once the rudder has returned the vessel back on course, the excess pressure is no longer on the sails, the tension is reduced in the jibsheet (7), and the excess tension in the spring tensioner (17), returns the tiller to its central position using the reverse motion of the assembly.

Conversely, as the wind moves towards the bows, the pressure in the sails' decreases, tension in the jibsheet is reduced, and the spring tensioner (17) rotates the winch platform (79), the winch (6), and the primary drive arm (80), clockwise. This action causes the tiller (1) to turn anticlockwise, together with the rudder shaft (2) and the rudder, steering the vessel down wind, as shown in Figure 15. Once the vessel is back on course, the pressure in the sails increase, causing an increased tension in the jibsheet, and consequently the tiller is returned to the central position using the reverse motion of the assembly.

The design shown in this example can also be used on vessels with wheel steering. An example of this is shown in Figure 18. Here, the secondary drive arm (81) clips on to attachment ring (87), which is clamped in a permanent manner to a wheel, spoke. The radius position of the attachment ring can be adjusted on installation to achieve the correct rudder movement.

al A locking mechanism should be employed in all the examples described above so that the vessel can be sailed manually' using the jib sheet winch, but not using the self-

steering system. An example of a locking system to prevent the winch from moving is described in Figure 16.

Figure 16 shows a close up view of the design described in Figure 13. Items, which were described in Figure 13, are: winch platform (10), winch (6), jib sheet (7), block (18), shock cord (17), pivot (82) winch platform (79), and primaly arm (80). Items, which relate to the locking mechanism, are rigging screw (83), deck-eye (85), snap shackle (86), and deck eye (87).

Rigging screw (83) is permanently attached to platform (10) via deck-eye (85). When sailing without the self-steering system, the rigging screw is attached at the opposite end to the moving platform (79) via the snap shackle (86), and deck-eye (87). When sailing with the self steering system, the rigging screw is detached from platform (79) by releasing the snap shackle (86).

The locking mechanism can also be used to help re-set the self-steering system when tacking (altering course from port tack to starboard tack, and visa versa, when sailing against the wind). The method of operation for changing from port tack (wind from the port side) to starboard tack (wind from the starboard side) is as follows: Initial setting - With the vessel using the self-steering system, on port tack, the starboard side winch is in operation. Prior to tacking, the port side rigging screw should be set, as shown in Figure l 6 After tacking, with the vessel on the starboard tack, the port winch is used. Once the jib has been adjusted for optimum sailing performance, the shock cord (17) is tensioned up until the rigging screw becomes slack. Once this has been achieved, the secondary drive arm is attached from the tiller to the primary drive arm (80), and the snap shackle (87) is released.

The reason for using a rigging screw for the mechanism described here is to provide some adjustment during installation.

Claims (32)

Claims

1. A steering arrangement for a sailing vessel which comprises a sail, a winch, a control line connecting the sail to the winch and a helm for steering the vessel, the steering arrangement comprising: a winch mount for mounting the winch to the vessel in a manner which permits movement of the winch relative to the vessel in response to wind force on the sail and the control line, and force transmitting means for translating movement of the winch mount into movement of the helm of the vessel.

2. A steering arrangement according to claim 1 wherein the arrangement is such that, in use, the helm is steered in a direction which opposes a change in direction of wind force on the sail whereby to keep the vessel on course.

3. A steering arrangement according to claim 1 or 2 further comprising tensioning means for opposing tension in the control line between the winch and the sail.

4. A steering arrangement according to claim 3 wherein the tensioning means connects between the winch mount and a mounting point on the vessel.

5. A steering arrangement according to claim 3 or 4 wherein the strength of the tensioning force applied by the tensioning means is adjustable.

6. A steering arrangement according to any one of claims 3 to 5 wherein the tensioning means is a shock cord.

7. A steering arrangement according to claim 6 wherein there are at least two shock cords for connecting between the mounting point and the winch mount, each shock cord being selectively connectable to the winch mount according to a required tension.

8. A steering arrangement according to any one of the preceding claims wherein the force transmitting means comprises first and second drive arms and a pivot arm, the pivot arm being pivotably mounted to the vessel at a position spaced from the winch mount, the first drive arm connecting between the winch mount and the pivot arm and the second drive arm connecting between the pivot arm and the helm.

9. A steering arrangement according to any one of claims 1 to 7 wherein the force transmitting means comprises a pivot arm which is pivotably mounted to the vessel at a position spaced from the winch mount, a first drive arm connecting between the winch mount and the pivot arm, a line connecting the pivot arm to the helm and a tensioning line connecting the helm to the vessel.

10. A steering arrangement according to any one of claims 1 to 7 wherein the force transmitting means comprises a pulley which is pivotably mounted to the vessel, a first drive arm mounted on the first pulley, a second drive arm hingedly connected to the first drive arm and to the helm and a cable arrangement for translating movement of the winch mount to rotational movement of the first pulley.

11. A steering arrangement according to claim 10 wherein the cable arrangement and the pulley are arranged such that movement of the winch mount causes a larger movement of the pulley.

12. A steering arrangement according to any one of claims 1 to 7 wherein there is a port-side winch mount and a starboard-side winch mount, and the force transmitting means connects both winch mounts to the helm.

13. A steering arrangement according to claim 12 further comprising a port-side pulley, a starboard-side pulley and a cable loop which passes around both the port-side pulley and the starboard-side pulley and acts upon the helm, the port-side pulley and

starboard-side pulley being connected to the winch mount on their respective sides of the vessel by cables.

14. A steering arrangement according to claim 13 wherein the cable loop further comprises a tensioner for maintaining tension in the cable loop.

15. A steering arrangement according to claim 13 or 14 further comprising a clutch for acting between the cable loop and the helm, the clutch being movable between an engaged position in which the cable loop acts on the helm to steer the vessel, and a disengaged position in which the cable loop does not act on the helm and the vessel can be manually steered.

16. A steering arrangement according to any one of claims 12 to 15 wherein the cable loop and cables are housed in protective guards.

17. A steering arrangement according to any one of the preceding claims wherein the winch mount permits movement of the winch in a linear direction along the vessel.

18. A steering arrangement according to claim l 7 wherein the winch mount comprises a platform for receiving the winch, runners mounted on the vessel and linear bearings for allowing the platform to roll along the runners.

19. A steering arrangement according to any one of claims 1 to 16 wherein the winch mount permits rotational movement of the winch about a mounting point on the vessel.

20. A steering arrangement according to any one of the preceding claims further comprising locking means for selectively locking the winch mount whereby to allow the vessel to be sailed by use of the control line.

21. A steering arrangement according to any one of the preceding claims wherein the force transmitting means acts upon a tiller of the vessel.

22. A steering arrangement according to any one of claims 1 to 20 wherein the force transmitting means acts upon a wheel for operating a rudder of the vessel.

23. A steering arrangement according to any one of the preceding claims wherein the sail is a foresail of the vessel.

24. A steering arrangement according to any one of the preceding claims further comprising a winch mounted on the winch mount.

25. A sailing vessel incorporating a steering arrangement according to any one of the preceding claims.

26. A winch mount for a sailing vessel comprising a mount for receiving a winch and for fixing to a surface of the vessel, the mount permitting movement of the winch relative to the vessel.

27. A winch mount according to any one of the preceding claims wherein the mount permits movement of the winch in a linear direction along the vessel.

28. A winch mount according to claim 27 comprising a platform for receiving the winch, runners for fixing to a surface of the vessel and linear bearings for allowing the platform to roll along the runners.

29. A winch mount according to claim 26 wherein the mount permits rotational movement of the winch about a mounting point on the vessel.

30. A winch mount according to any one of claims 26 to 29 further comprising locking means for selectively locking the position of the winch mount with respect to the vessel.

31. A winch incorporating a winch mount according to any one of claims 26 to 30.

32. A steering arrangement, sailing vessel, winch or winch mount substantially as described herein with reference to, or as shown in, Figures 3 to 18 of the accompanying drawings.