SAILING CRAFT
United States Patent 3610190
A mast of a sailing craft is pivotally mounted so that it can heel independently of the craft, and is supported athwartship by apparatus which automatically controls heel of the mast and comprises standing rigging shrouds connected to crosstrees pivoted to the mast, running rigging stays connected at one end to the crosstrees and passed around pulleys at the upper part of the mast, and fixed tensioning mean to which the opposite ends of the running rigging stays are connected.
US Patent References:
Sailing vessel
Blackman - July 1944 - 2353007
Sail rigging
Schwaneke et al. - August 1963 - 3099976
Mast compensating the list of sailingboats of all classes
Criou - June 1967 - 3323480
Sailing vessel
Blackman - July 1944 - 2353007
Sail rigging
Schwaneke et al. - August 1963 - 3099976
Mast compensating the list of sailingboats of all classes
Criou - June 1967 - 3323480
Application Number:
04/835648
Publication Date:
10/05/1971
Filing Date:
06/23/1969
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
114/91
International Classes:
B63B15/02; B63B15/00; B63B35/00; B63H9/00
Field of Search:
114/39,102,90,91
Primary Examiner:
Blix, Trygve M.
Claims:
I claim
1. A sailing craft including a mast mounted thereon by a pivotal joint which permits the mast to heel relative thereto, and apparatus which supports the mast athwartship and provides automatic control of the extent of the heel of the mast according to wind condition, and which comprises standing and running rigging in combination each side of the mast, crosstrees pivoted on the mast, and fixed resilient tensioning means, the standing rigging comprising shrouds anchored at their lower ends to fixed parts of the craft and at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
2. A sailing craft according to claim 1 wherein the mast is pivoted to the craft at or closely adjacent to the deck line.
3. A sailing craft according to claim 1 wherein the mast is permitted to heel through at least 20° to either side of its normal upright position.
4. A sailing craft according to claim 1 wherein the mast is permitted to heel up to 70° to either side of its normal upright position.
5. A sailing craft according to claim 1 including a plurality of masts adapted to heel independently of one another.
6. A sailing craft according to claim 1 including a plurality of masts adapted to heel together.
7. A sailing craft according to claim 6 wherein the masts are mounted on a common pivot shaft.
8. A sailing craft according to claim 1 wherein the apparatus which supports the mast athwartship and provides automatic control of the extent of the heel of the mast, is all mounted on the craft above deck level.
9. A sailing craft according to claim 1 wherein the mast is adjustable bodily longitudinally of the craft.
10. Apparatus for a sailing craft, comprising a mast adapted to be pivotally mounted on the craft so that the mast can heel relative thereto, and apparatus which is adapted in use to support the mast athwartship and provide automatic control of the extent of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination for each side of the mast, crosstrees pivoted on the mast and resilient tensioning means fixed against movement, the standing rigging comprises shrouds adapted to be anchored at their lower ends to fixed parts of the sailing craft and connected at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
11. Apparatus for a sailing craft, comprising mounting means for pivotally mounting a mast of a sailing craft so that the mast can heel relative to the craft, and apparatus which is adapted in use to support the mast athwartship and provide automatic control of the extent of of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination for each side of the mast, crosstrees adapted to be pivoted to the mast, and resilient tensioning means adapted to be fixed against movement, the standing rigging comprising shrouds adapted to be anchored at their lower ends to fixed parts of the sailing craft and connected at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
12. Apparatus according to claim 11 wherein the resilient tensioning means on the mast above deck level.
13. Apparatus according to claim 11 wherein the resilient tensioning means is hydraulically actuated.
14. Apparatus according to claim 11 wherein the resilient tensioning means is spring actuated.
15. Apparatus according to claim 11 wherein the resilient tensioning means is adjustable to vary the extent by which the mast is allowed to heel under particular wind forces, and to vary the initial resistance to heeling of the mast.
16. Apparatus according to claim 11 wherein the resilient tensioning means imposes tension which takes effect in stages, each successive stage increasing the tension as the angle of heel increases.
17. Apparatus according to claim 11 wherein the resilient tensioning means comprises three sets of springs which operate successively on a movable member connected to the running rigging to increase the resistance to movement of the movable member, and thereby of the running rigging, as the angle of heel of the mast increases.
18. Apparatus according to claim 17 wherein the springs comprise a main helical tension spring which is connected directly to the movable member and provides initial resistance to movement of the member; a plurality of secondary tension springs connected to a movable element with which the movable member is arranged to cooperate after a predetermined extent of movement to cause the element to move with the member and bring the secondary tension springs into effect so that they act in combination with the main tension spring to resist movement of the movable member and running rigging; and a compression spring which is arranged to act upon the movable element after a predetermined extent of movement of the element to act in combination with the main and secondary tension springs, through the element, on the movable member to resist movement of the member.
19. Apparatus according to claim 17 wherein the movable member is a threaded spindle connected to a tensioner included in the running rigging by means of which initial tensioning of the running rigging and springs of the resilient tensioning means can be adjusted.
20. Apparatus according to claim 11 wherein the shrouds of the standing rigging are provided with tensioners for adjusting the initial tensioning of the rigging.
21. Apparatus according to claim 11 wherein the shrouds are provided with tension springs to absorb shock loading on the shrouds.
22. Apparatus according to claim 11 wherein the crosstrees are formed by pairs of arms which are pivotally mounted on each side of the mast.
23. Apparatus according to claim 11 wherein the pulleys or sheaves are adjustable to vary their spacings from the mast.
24. Apparatus according to claim 10 wherein the mast is coupled to means adapted automatically to convert heeling movement of the mast into drive for automatically operating and adjusting at least some of the other gear of the craft as the mast heels.
25. Apparatus according to claim 24 wherein the mast is connected to a gear wheel on a pivot shaft, about the axis of which the mast heels, which gear wheel drives through gearing a shaft from which the drive for automatically operating and other gear of the craft is taken.
26. Apparatus according to claim 25 wherein the mast is bodily adjustable axially of the pivot shaft to alter its position longitudinally of the craft.
27. Apparatus according to claim 10 wherein stop means is provided to prevent excessive heeling of the mast and complete collapse of the mast in the event of failure of the apparatus controlling heel of the mast.
28. Apparatus according to claim 27 wherein the stop means comprises hydraulic buffers positioned each side of the mast near the pivot of the mast.
1. A sailing craft including a mast mounted thereon by a pivotal joint which permits the mast to heel relative thereto, and apparatus which supports the mast athwartship and provides automatic control of the extent of the heel of the mast according to wind condition, and which comprises standing and running rigging in combination each side of the mast, crosstrees pivoted on the mast, and fixed resilient tensioning means, the standing rigging comprising shrouds anchored at their lower ends to fixed parts of the craft and at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
2. A sailing craft according to claim 1 wherein the mast is pivoted to the craft at or closely adjacent to the deck line.
3. A sailing craft according to claim 1 wherein the mast is permitted to heel through at least 20° to either side of its normal upright position.
4. A sailing craft according to claim 1 wherein the mast is permitted to heel up to 70° to either side of its normal upright position.
5. A sailing craft according to claim 1 including a plurality of masts adapted to heel independently of one another.
6. A sailing craft according to claim 1 including a plurality of masts adapted to heel together.
7. A sailing craft according to claim 6 wherein the masts are mounted on a common pivot shaft.
8. A sailing craft according to claim 1 wherein the apparatus which supports the mast athwartship and provides automatic control of the extent of the heel of the mast, is all mounted on the craft above deck level.
9. A sailing craft according to claim 1 wherein the mast is adjustable bodily longitudinally of the craft.
10. Apparatus for a sailing craft, comprising a mast adapted to be pivotally mounted on the craft so that the mast can heel relative thereto, and apparatus which is adapted in use to support the mast athwartship and provide automatic control of the extent of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination for each side of the mast, crosstrees pivoted on the mast and resilient tensioning means fixed against movement, the standing rigging comprises shrouds adapted to be anchored at their lower ends to fixed parts of the sailing craft and connected at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
11. Apparatus for a sailing craft, comprising mounting means for pivotally mounting a mast of a sailing craft so that the mast can heel relative to the craft, and apparatus which is adapted in use to support the mast athwartship and provide automatic control of the extent of of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination for each side of the mast, crosstrees adapted to be pivoted to the mast, and resilient tensioning means adapted to be fixed against movement, the standing rigging comprising shrouds adapted to be anchored at their lower ends to fixed parts of the sailing craft and connected at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
12. Apparatus according to claim 11 wherein the resilient tensioning means on the mast above deck level.
13. Apparatus according to claim 11 wherein the resilient tensioning means is hydraulically actuated.
14. Apparatus according to claim 11 wherein the resilient tensioning means is spring actuated.
15. Apparatus according to claim 11 wherein the resilient tensioning means is adjustable to vary the extent by which the mast is allowed to heel under particular wind forces, and to vary the initial resistance to heeling of the mast.
16. Apparatus according to claim 11 wherein the resilient tensioning means imposes tension which takes effect in stages, each successive stage increasing the tension as the angle of heel increases.
17. Apparatus according to claim 11 wherein the resilient tensioning means comprises three sets of springs which operate successively on a movable member connected to the running rigging to increase the resistance to movement of the movable member, and thereby of the running rigging, as the angle of heel of the mast increases.
18. Apparatus according to claim 17 wherein the springs comprise a main helical tension spring which is connected directly to the movable member and provides initial resistance to movement of the member; a plurality of secondary tension springs connected to a movable element with which the movable member is arranged to cooperate after a predetermined extent of movement to cause the element to move with the member and bring the secondary tension springs into effect so that they act in combination with the main tension spring to resist movement of the movable member and running rigging; and a compression spring which is arranged to act upon the movable element after a predetermined extent of movement of the element to act in combination with the main and secondary tension springs, through the element, on the movable member to resist movement of the member.
19. Apparatus according to claim 17 wherein the movable member is a threaded spindle connected to a tensioner included in the running rigging by means of which initial tensioning of the running rigging and springs of the resilient tensioning means can be adjusted.
20. Apparatus according to claim 11 wherein the shrouds of the standing rigging are provided with tensioners for adjusting the initial tensioning of the rigging.
21. Apparatus according to claim 11 wherein the shrouds are provided with tension springs to absorb shock loading on the shrouds.
22. Apparatus according to claim 11 wherein the crosstrees are formed by pairs of arms which are pivotally mounted on each side of the mast.
23. Apparatus according to claim 11 wherein the pulleys or sheaves are adjustable to vary their spacings from the mast.
24. Apparatus according to claim 10 wherein the mast is coupled to means adapted automatically to convert heeling movement of the mast into drive for automatically operating and adjusting at least some of the other gear of the craft as the mast heels.
25. Apparatus according to claim 24 wherein the mast is connected to a gear wheel on a pivot shaft, about the axis of which the mast heels, which gear wheel drives through gearing a shaft from which the drive for automatically operating and other gear of the craft is taken.
26. Apparatus according to claim 25 wherein the mast is bodily adjustable axially of the pivot shaft to alter its position longitudinally of the craft.
27. Apparatus according to claim 10 wherein stop means is provided to prevent excessive heeling of the mast and complete collapse of the mast in the event of failure of the apparatus controlling heel of the mast.
28. Apparatus according to claim 27 wherein the stop means comprises hydraulic buffers positioned each side of the mast near the pivot of the mast.
Description:
This invention relates to sailing craft of monohull and multihull form, and is applicable to such craft whether they have conventional cloth sails, vanes of stiff material, or a combination of sails and vanes.
The usual practice hitherto has been to have the or each mast of a sailing craft, at least when in use, rigidly fixed in relation to the hull or hulls. Thus, when the mast heels under wind forces on on the sails or vanes it supports, the hull or hulls also heel, with consequent undesirable change in wetted surface area of the hull or hulls and resultant asymmetrical underwater hull shape, which tends to urge the craft to veer off course, and risk of the craft's capsizing.
The object of the present invention is to reduce the tendency of the hull or hulls to heel, and thereby to make sailing easier and safer.
According to one aspect of the present invention there is provided a sailing craft including a mast mounted thereon by a pivoted joint which permits the mast to heel relative thereto, and apparatus which supports the mast athwartship and provides automatic control of the extent of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination each side of the mast, crosstrees pivoted on the mast, and fixed resilient tensioning means, the standing rigging comprising shrouds anchored at their lower ends to fixed parts of the craft and at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
The invention may be applied to existing sailing craft. Thus according to a second aspect of the invention there is provided apparatus for a sailing craft, comprising a mast adapted to be pivotally mounted on the craft so that the mast can heel relative thereto, and apparatus which is adapted in use to support the mast athwartship and provide automatic control of the extent of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination for each side of the mast, crosstrees pivoted, on the mast, and resilient tensioning means fixed, against movement, the standing rigging comprising shrouds adapted to be anchored at their lower ends to fixed parts of the sailing craft and connected at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
Furthermore, the invention may be applied to existing sailing craft making use of the existing masts. In this respect, according to a third aspect of the present invention there is provided apparatus for a sailing craft, comprising mounting means for pivotally mounting a mast of a sailing craft so that the mast can heel relative to the craft, and apparatus which is adapted in use to support the mast athwartship and provide automatic control of the extent of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination for each side of the mast, crosstrees adapted to be pivoted to the mast, and resilient tensioning means adapted to be fixed, against movement, the standing rigging comprising shrouds adapted to be anchored at their lower ends to fixed parts of the sailing craft and connected at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
On a monohull sailing craft the mast preferably is, or is adapted to be, pivotally mounted on the hull at or closely adjacent to the deck line. This is in order to allow as wide a range of heel of the mast to either side of the hull, as possible. It will be appreciated that if the mast is pivoted below deck level, the gunwales, for instance, limit the range of heel possible, and that the lower the pivot below the deck the more limited the range of heel will be. It is desirable that the mast should be able to heel through at least 20° and preferably up to 70°, to either side of its normal upright condition. The wider the range of heel the less risk there is of "knock down" capsizing, because the more wind will be spilled from the sails or vanes carried by the mast.
If the mast pivot is above deck level it is best positioned on the longitudinal centerline of the hull passing through the top of the prow and the stern of the hull, so that the pivot will be in line with the anchorage points of fore and aft stays of the mast and therefore the tension of these stays will be unaffected by heeling of the mast.
On a multihull craft the mast is also preferably pivoted at or above deck level of the hulls for the same purpose of allowing as wide a range of heel of the mast as possible.
Where there are several masts they may be arranged to heel independently of one another or together. In the case of their being arranged to heel together, the masts may be mounted on a common pivot shaft or axle.
If desired, the mast may be coupled to means adapted automatically to adjust at least some of the trim gear of the craft as the mast heels, to compensate for the change in angle of the mast, in order to maintain the speed and course of the craft without halting the progress of the craft under the sail conditions set. Included in the trim gear adjusted in this way may be the rudder, trim tabs and stabilizers, and also the sheets to sails or vanes. Additionally the mast heel may be arranged to reduce sail or vane area by reefing, or lowering the sails or vanes. If the craft is fitted with self-steering gear, this too may be arranged to be adjusted as the mast heels to make any correction which may be necessary to keep the craft on a set course.
The pivoted crosstrees serve to spread the rigging from the mast and provide lever motion as the mast heels which enables the mast to heel smoothly and steadily, and return smoothly and easily to its normal, upright position after heeling.
The resilient tensioning means may be spring or hydraulically actuated. Preferably the tensioning means is mounted, or is adapted to be mounted, on the mast above deck level, so that all the rigging controlling the heel of the mast is then above deck level. This has several advantages. For example, if the invention is applied to an existing craft, modification of the hull to accept the rigging is not necessary; also if a fault occurs in the rigging, as everything is above deck level, the cause of the fault can easily be spotted, and access can quickly and readily be gained to a faulty part to correct, or if necessary replace, it. Also, of course hull space is not taken up by the rigging. The tension imposed by the tensioning means may be adjustable to vary the extent by which the mast is allowed to heel under particular wind forces, and to vary the initial resistance to heeling of the mast. Also the tensioning means may be arranged so that the tension imposed comes into effect in stages, each successive stage increasing the tension as the angle of heel increases.
Initial tensioning of the standing and running rigging to support the mast correctly in its normal upright position may be done through the resilient tensioning means, or alternatively, or in addition, tensioners may be provided in the standing rigging or running rigging, or both, to provide the required initial tensioning.
There may be bodily adjustment of the position of the mast in the longitudinal direction of the craft, if desired.
An embodiment of the present invention will now be described by way of example with reference to the accompanying drawings in which:
FIG. 1 is an elevation from the stern of a monohull sailing craft embodying the present invention, and showing a mast of the craft in its normal, upright position;
FIG. 2 is a further elevation from the stern of the craft, but showing the mast in a heeled condition;
FIG. 3 is an enlarged part sectional elevation of the mast of the craft shown in FIGS. 1 and 2;
FIGS. 4, 5, 6 and 7 are enlarged detailed views respectively on lines 4--4, 5--5, 6--6 and 7--7 of FIG. 3;
FIG. 8 is a detail view of a pivotal mounting of the mast;
FIG. 9 is a section on line 9--9 of FIG. 8,
FIG. 10 is a simplified perspective view of a multimasted craft in which the masts are able to heel independently of one another, and
FIG. 11 is a simplified perspective view of a multimasted craft in which the masts heel together.
In this embodiment the invention is applied to a small single-masted sailing craft. The craft has a hull 10 and a mast 11, preferably of tubular metal construction, which is pivoted at its foot by a pivoted mounting 12 to the hull 10 close to the level of the deck 13 of the hull. The pivotal mounting 12 allows the mast 11 to heel relative to the hull 10, both to port, as shown in FIG. 2, and to starboard. Fixed fore-and-aft stays, not shown, connected to the top of the mast by swivels and to the prow and stern of the hull, also by swivels, support the mast against fore and aft strains. At each side, the mast, as shown in FIG. 3, is supported by a combination of standing rigging 14 and running rigging 15, which with a resilient tensioning device 16 to which the running rigging is connected, also automatically control the heel of the mast according to wind forces acting on sails or vanes, not shown, supported by the mast.
The standing rigging 14 at each side of the mast is formed by a pair of shrouds 17, FIG. 4, each fitted at the lower end with a turnbuckle 18 connected to a strong, closed helical tension spring 19 which hooks into one of a series of holes 20 in one flange of an angle section metal bracket 21 which is secured to the deck 13 of the hull near the side of the hull, or alternatively to the side of the hull, or to the gunwale of the side. The upper ends of each pair of shrouds 17 are connected to opposite ends of a spindle 22, FIG. 5, journaled in and extending transversely between the outer end portions of one of two pairs of parallel arms 23 extending from opposite sides of the mast 11, and pivoted at their inner ends about a horizontal axis to a bracket 24 clamped to the mast approximately halfway up the mast. The two pairs of pivoted arms 23 constituted crosstrees. For strengthening purposes the outer ends of the pivoted arms 23 of each pair are connected together, beyond the spindle 22, by a crosspiece 25. The ends of the spindle 22 journaled to each pair of pivoted arms 23 project beyond the sides of the arms and the connection of the upper ends of the shrouds 17 to the spindle is made outside the arms. There is allowance for relative rotation between the ends of the shrouds and the spindle 22.
The running rigging 15 at each side of the mast is formed, as shown in FIG. 3, by a cable stay 26 which is connected at one end to the spindle 22 between the pair of pivoted arms 23 at the same side of the mast. Spacer sleeves 27, FIG. 5, fitted on the spindle 22 each side of the connection of the end of the stay 26 to the spindle, keep the end of the stay spaced centrally between the pair of pivoted arms 23. From the spindle 23 the stay 26 extends upwards and over a pulley 28, or sheave, FIGS. 3 and 5, supported by a bracket 29 clamped to the mast near its upper end. Each pulley 28 is mounted between a pair of U-shaped carrier arms 30 connected to the brackets 29 which project laterally to the side of the mast. The carrier arms 30 are joined laterally outwardly of the pulley by a crosspiece 31 for strengthening purposes. The pulley 28 can be adjusted laterally of the carrier arms 30 to some extent to alter the distance by which it is spaced from the mast. This is made possible by aligned horizontally extending slots 32 in the two carrier arms 30, and a headed bolt 33, FIG. 5, which forms the pivot pin of the pulley 28 and passes through, and can be moved along, the slots and is fitted with a nut 34 to secure the bolt, and thus the pulley, in any adjusted position. After passing around the pulley 28 the stay 26 extends downwards alongside the mast 11 and is fitted at its other end with a swivel 35 which is connected to a tensioner 36, which is in turn connected to the resilient tensioning device 16. By suitable lateral adjustment; if necessary, of the position of the pulley 28 on the carrier arms 30, the downward run of the stay 26 is set so that it extends parallel to the mast.
Each tensioner 36, as shown in FIG. 6, comprises a shackle 37, to which the swivel 35 is attached, a pair of eye-ended links 38, the eyes at the upper ends of which are connected to the shackle 37, and the eyes at the lower ends of which are connected to opposite ends of a bar 39 having an internally threaded hole at the center of its length into which is screwed the upper end of a vertically extending screw-threaded spindle 40 of the associated resilient tensioning device 16.
Each resilient tensioning device 16 comprises, as shown in FIGS. 3 and 7, an open substantially rectangular housing 41 formed from upper and lower horizontal, reinforced metal plates 42 and 43 respectively, each bolted at one end to one of two clamping brackets 44, by which the housings 41 of both tensioning devices are rigidly clamped to the sides of the mast, and inner and outer vertical, metal channel members 45 and 46 respectively, the inner channel member 45 being bolted at its ends to the brackets 44, and the outer channel member being bolted to the free ends of the upper and lower plates 42 and 43. If desired, the plates 42 and 43 may alternatively be welded or brazed to the clamping brackets 44, and similarly the inner and outer channel members may respectively be welded or brazed to the clamping brackets and the upper and lower plates 42 and 43. In the housing 41 is a metal floater plate 47 which extends horizontally between and engages at its ends in vertically elongated guide slots 48 in the inner and outer channel members 45 and 46. The guide slots 48 allow the floater plate 47 to move up and down in the housing 41. The screw-threaded spindle 40 previously mentioned passes through a central plain hole 49 in the upper plate 42, and at its lower end through a plane aperture 50 in the floater plate 47 aligned with the plain hole 49. Fitted around the spindle 40 between the upper plate 42 and the floater plate 47 is a strong, open helical compression spring 51 which is arranged to bear at its ends on those two plates, although normally it just rests on the floater plate and does not exert any downward loading on the floater plate. Underneath the floater plate 47, the spindle 40 is fitted with a plate metal washer 52, and has underneath the washer 52 an eye 53 to which is attached the upper end of a strong, main tension spring 54, attached at its lower end to an eyebolt 55 secured to the upper side of the lower plate 43. The main tension spring 54 normally acts to urge the spindle 40, and thus the downward run of the associated stay 26, downwards. On the underside of the floater plate 47 are secured four eyebolts 56, two each side of the aperture 50, to which are attached the upper ends of four closed, secondary helical tension springs 57, which extend parallel to, two each side of, the main tension spring 54, and are attached at their lower ends to four additional eyebolts 58 secured to the upperside of the lower plate 43. These four secondary tension springs 57 are individually weaker than the main tension spring 54, and they normally urge the floater plate downwards. The action of the compression spring 51, the main tension spring 54, and the secondary tension springs 57 will be described further hereafter.
The bottom of the mast 11 may simply be connected by a pivot pin to the pivoted mounting 12 secured to the hull, or it may be connected by a universal joint to the mounting to allow the mast not only to heel transversely of the hull but also in the other directions as well. Alternatively the pivot mounting 12 may take the form shown in FIGS. 8 and 9. In this the mast is supported at its foot by a pair of spaced coaxial, large diameter, gear wheels 59, as shown in FIGS. 8 and 9, keyed to, for rotation with, a pivot shaft 60 journaled in end wall plates 61 of a boxlike framework 62 which is rigidly secured underneath the deck 13 of the hull. The foot of the mast is held by a clamping bracket 63 which extends between, and is rigidly secured to the gear wheels 59 above the pivot shaft 60. The pivot shaft 60 extends in the longitudinal direction of the hull, and the keyed connection of the gear wheels 50 to the shaft allows the wheels to be moved axially of the shaft to alter the position of the mast longitudinally of the hull, for example as indicated in FIG. 8. The framework 62 supports the pivot shaft 60 only just below deck level. The framework 62 is rigidly bolted to the underside of the deck. If required, it may also be secured to frame members of the hull below deck.
The pivot shaft 60 provides the pivot of the mast, allowing the mast to heel transversely of the hull. As the mast heels it turns the shaft and the gear wheels 59. Mounted on each of two parallel shafts 64 below and to either side of the pivot shaft 60, are spur gears 65 which mesh with the gear wheels 59. These two shafts 64 are also journaled in the end wall plates 61 of the framework 62, and the spur gears 65 they carry can be adjusted axially of the shafts. Flexible or other drives, not shown, are coupled to the shafts 64 to take drive imparted to the shafts from the pivot shaft by heeling of the mast to operate and automatically adjust according to the heel, at least some of the trim gear of the craft, and/or sails or vanes, or self-steering gear of the craft.
Also supported by the framework each side of the pivot shaft are two hydraulic buffers 66 which extend towards the clamping bracket 63 holding the foot of the mast 11.
In use the mast is set up on the hull so that it extends perpendicularly of the hull. The turnbuckles 18 of the standing rigging 14 and the tensioners 36 of the running rigging are adjusted to tension the two sets of rigging as required, and to ensure that the mast is supported perpendicularly of the hull athwartship. The tensioning devices 16, acting through their associated running and standing riggings, hold the mast in the upright condition while wind forces on the sails or vanes carried by the mast are fairly light. While the mast is upright the pivoted arms 23 extend horizontally from the mast. The combined lengths of the shrouds 17 of the standing rigging and the strong tension springs 19 once set normally remain fixed, because the springs usually do not vary in length as they are provided solely for the purpose of damping sudden heavy shock loads on the rigging caused for example by unexpected gusting in severe squall conditions and heavy sea motion.
Under stronger wind forces the mast is automatically allowed to heel to leeward under the control of the standing and running riggings and the resilient tensioning devices 16. As the mast heels, about the axis of the pivot shaft 60, the standing rigging 14 on the windward side of the mast causes the pivoted arms 23 on that side of the mast to pivot downwards with respect to the mast, pulling the attached end of the cable stay 26 of the associated running rigging 15 downwardly with them, so that there is resultant upward movement of the run of the stay 26 which extends alongside the mast. This in turn causes the threaded spindle 40 of the associated resilient tensioning device 16, to move upwards relative to the housing 41. In the early stages of heel the upward movement of the spindle 40 is resisted and hence the extent of heel of the mast is controlled, only by the main tension spring 54 attached to the spindle 40. If the heel induced by the prevailing wind forces causes the spindle 40 to be moved upwards by the stay 26 sufficiently for the washer 52 at the bottom of the spindle to engage and move the floater plate 47 upwards in the housing 41, then the four secondary tension springs 57 also come into effect to help to control heeling of the mast. There is still further resistance to upward movement of the spindle, and heeling of the mast, if the heel of the mast is great enough for the stay to cause the spindle 40 to move the floater plate 47 upwards sufficiently for the compression 51 to come into effect and exert downward pressure on the floater plate. It will be understood from the foregoing that as the angle of heel of the mast increases the resistance to heel imposed by the various springs of the resilient tensioning device is progressively increased. When the wind forces decrease the action of the springs on the stay 26 automatically returns the mast to its normal upright position.
Slack in the standing and running rigging on the leeward side of the mast is automatically taken up by the resilient tensioning device on the leeward side of the mast. In fact all the slack may not be completely taken up as the angle of heel increases, but this in practice does not matter as long as there is not so much slack that there is risk perhaps of rigging hanging over the side of the hull and dragging in the water.
The pivoted arms 23 spread the rigging from the mast and provide lever motion as the mast heels, which enables smooth, steady heeling movement of the mast to be achieved, rather than sudden erratic movement, which is essential to obtain the full benefit of the present arrangement. The action of the pivoted arms on the rigging also allows the mast to return easily and smoothly to its normal, upright position.
A very wide range of heel is possible with the arrangement described and illustrated. Up to 70° heel has been achieved which in practice is about the maximum required because at that angle all wind is spilled from the sails or vanes carried by the mast. With large angles of heel there will be some heeling of the hull itself, but this will be comparatively small and certainly not sufficient for there to be risk of capsizing and for the change of wetted surface area and underwater shape of the hull to urge the craft to deviate excessively.
The strength of the springs incorporated in each resilient tensioning device are selected according to the extent of mast heel required to be allowed under particular wind forces, and according to the size and weight of mast and sail or vane area to be carried by the mast. In the drawings the springs of the devices are illustrated as being quite short, as the craft is small, but for larger craft longer and stronger springs may be substituted. To take longer springs the housings 41 may readily be extended by substituting longer inner and outer channel members 45 and 46 between the upper and lower plates 42 and 43 of the housing. Apart from modifications of this nature, the standing and running rigging, pivoted arms 23, pulleys 28 and resilient tensioning devices 16 may readily be interchanged between craft of different sizes. The fact that the pivoted arms 23, pulleys 28 and tensioning devices 16 are all attached by clamping brackets to the masts, enables them to be quite easily detached from the mast for fitting to the mast of another craft. They can also be easily fitted to an existing mast of a craft to replace the standard mast rigging. It would only be necessary to provide the mast with a pivoted mounted on the hull, which could be done relatively simply and without having to make extensive alterations to the mast and hull, particularly if a simple pivot of the form previously mentioned is used. Even using the pivoted mounting described and illustrated, however, not undue modification of an existing craft would be necessary to take the mounting. It would be possible, instead of positioning it below deck as described, to have it on top of the deck, which would then involve little or no modification of an existing hull.
It may be desirable, especially if the apparatus is to be applied to an existing mast, for padding to be inserted between the mast and the clamping brackets of the resilient tensioning devices, the pivoted arms 23, and the pulleys 28, to provide increased friction, and prevent scratch damage to the mast. If padding is used, then the quality of the finish of the parts of the brackets is not so critical as it would otherwise be, and hence the cost of their manufacture can be reduced to some extent. If the apparatus is subsequently removed from the mast, the mast can be easily returned to its original condition with the standard rigging.
If the apparatus is built into a craft the various brackets mentioned may be permanently fixed to the mast.
With the arrangement of the standing riggings, running riggings and tensioning devices described and illustrated, the tendency is for the mast to be lifted from the deck, which has the advantage of reducing the direct loading on the pivot of the mast. All the apparatus controlling heel of the mast is above deck.
The buffers 66 act as stops to prevent the mast heeling excessively, for example under gusting conditions. Where the maximum desired angle of heel in either direction is reached, the buffer 66 to the side of the mast to which the mast has heeled abuts against the bracket holding the foot of the mast. The buffers 66 also provide stops to complete collapse of the mast if the riggings should fail.
If desired, a braking action may be manually imposed upon the heel of the mast in either direction by means of a disc brake, not shown, which operates on the pivot shaft.
If the mast is repositioned bodily longitudinally of the hull, by moving it along the pivot shaft, as indicated in FIG. 8, the connections of the strong tension springs 19 to the bracket 21 can be appropriately adjusted by hooking the springs into different holes 20 of the bracket.
It will be appreciated that while the apparatus for automatically controlling heel of the mast has been described and illustrated as applied to a monohull sailing craft, the apparatus could readily be applied to a multihull craft.
With the present invention, counterweighting of the hull or hulls, heel or float of the craft to which it is applied, is not necessary to offset the effect of wind forces which in craft having a conventional, fixed mast normally cause heel of the craft rather than increased speed of travel. Hence the design of the hull or hulls, keel or float can be concentrated on reduction of the effect of wave motion, although some allowance may have to be made in the design to take into account the effect of the weight of the mast when the mast heels, this depending largely upon the size of the craft and the extent by which the mast is permitted to heel.
In FIG. 11 of the accompanying drawings there is illustrated a multimasted craft the masts 111 of which are pivotally mounted on the hull independently of one another so that they are able to heel independently of one another. Each mast 111 has its own individual pivoted mounting 112 which is similar to the pivoted mounting 12 described above and illustrated in FIGS. 8 and 9 of the drawings.
A multimasted craft is also shown in FIG. 12 of the drawings but in that craft the masts 211 are all mounted on and are keyed to for rotation with a single extended pivot shaft 260 so that they will all heel together. The manner in which each mast 211 is mounted on the extended pivot shaft 260 is substantially similar to that in which the single mast 11 described above is mounted on its pivot shaft 60.
The usual practice hitherto has been to have the or each mast of a sailing craft, at least when in use, rigidly fixed in relation to the hull or hulls. Thus, when the mast heels under wind forces on on the sails or vanes it supports, the hull or hulls also heel, with consequent undesirable change in wetted surface area of the hull or hulls and resultant asymmetrical underwater hull shape, which tends to urge the craft to veer off course, and risk of the craft's capsizing.
The object of the present invention is to reduce the tendency of the hull or hulls to heel, and thereby to make sailing easier and safer.
According to one aspect of the present invention there is provided a sailing craft including a mast mounted thereon by a pivoted joint which permits the mast to heel relative thereto, and apparatus which supports the mast athwartship and provides automatic control of the extent of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination each side of the mast, crosstrees pivoted on the mast, and fixed resilient tensioning means, the standing rigging comprising shrouds anchored at their lower ends to fixed parts of the craft and at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
The invention may be applied to existing sailing craft. Thus according to a second aspect of the invention there is provided apparatus for a sailing craft, comprising a mast adapted to be pivotally mounted on the craft so that the mast can heel relative thereto, and apparatus which is adapted in use to support the mast athwartship and provide automatic control of the extent of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination for each side of the mast, crosstrees pivoted, on the mast, and resilient tensioning means fixed, against movement, the standing rigging comprising shrouds adapted to be anchored at their lower ends to fixed parts of the sailing craft and connected at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to the crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
Furthermore, the invention may be applied to existing sailing craft making use of the existing masts. In this respect, according to a third aspect of the present invention there is provided apparatus for a sailing craft, comprising mounting means for pivotally mounting a mast of a sailing craft so that the mast can heel relative to the craft, and apparatus which is adapted in use to support the mast athwartship and provide automatic control of the extent of the heel of the mast according to wind conditions, and which comprises standing and running rigging in combination for each side of the mast, crosstrees adapted to be pivoted to the mast, and resilient tensioning means adapted to be fixed, against movement, the standing rigging comprising shrouds adapted to be anchored at their lower ends to fixed parts of the sailing craft and connected at their upper ends to the crosstrees which are pivoted to an intermediate part of the mast so that they can swing up and down relative to the mast, and the running rigging comprising stays which are connected at their one end to crosstrees, pass around pulleys or sheaves at the upper part of the mast, and are connected at their other ends to the resilient tensioning means.
On a monohull sailing craft the mast preferably is, or is adapted to be, pivotally mounted on the hull at or closely adjacent to the deck line. This is in order to allow as wide a range of heel of the mast to either side of the hull, as possible. It will be appreciated that if the mast is pivoted below deck level, the gunwales, for instance, limit the range of heel possible, and that the lower the pivot below the deck the more limited the range of heel will be. It is desirable that the mast should be able to heel through at least 20° and preferably up to 70°, to either side of its normal upright condition. The wider the range of heel the less risk there is of "knock down" capsizing, because the more wind will be spilled from the sails or vanes carried by the mast.
If the mast pivot is above deck level it is best positioned on the longitudinal centerline of the hull passing through the top of the prow and the stern of the hull, so that the pivot will be in line with the anchorage points of fore and aft stays of the mast and therefore the tension of these stays will be unaffected by heeling of the mast.
On a multihull craft the mast is also preferably pivoted at or above deck level of the hulls for the same purpose of allowing as wide a range of heel of the mast as possible.
Where there are several masts they may be arranged to heel independently of one another or together. In the case of their being arranged to heel together, the masts may be mounted on a common pivot shaft or axle.
If desired, the mast may be coupled to means adapted automatically to adjust at least some of the trim gear of the craft as the mast heels, to compensate for the change in angle of the mast, in order to maintain the speed and course of the craft without halting the progress of the craft under the sail conditions set. Included in the trim gear adjusted in this way may be the rudder, trim tabs and stabilizers, and also the sheets to sails or vanes. Additionally the mast heel may be arranged to reduce sail or vane area by reefing, or lowering the sails or vanes. If the craft is fitted with self-steering gear, this too may be arranged to be adjusted as the mast heels to make any correction which may be necessary to keep the craft on a set course.
The pivoted crosstrees serve to spread the rigging from the mast and provide lever motion as the mast heels which enables the mast to heel smoothly and steadily, and return smoothly and easily to its normal, upright position after heeling.
The resilient tensioning means may be spring or hydraulically actuated. Preferably the tensioning means is mounted, or is adapted to be mounted, on the mast above deck level, so that all the rigging controlling the heel of the mast is then above deck level. This has several advantages. For example, if the invention is applied to an existing craft, modification of the hull to accept the rigging is not necessary; also if a fault occurs in the rigging, as everything is above deck level, the cause of the fault can easily be spotted, and access can quickly and readily be gained to a faulty part to correct, or if necessary replace, it. Also, of course hull space is not taken up by the rigging. The tension imposed by the tensioning means may be adjustable to vary the extent by which the mast is allowed to heel under particular wind forces, and to vary the initial resistance to heeling of the mast. Also the tensioning means may be arranged so that the tension imposed comes into effect in stages, each successive stage increasing the tension as the angle of heel increases.
Initial tensioning of the standing and running rigging to support the mast correctly in its normal upright position may be done through the resilient tensioning means, or alternatively, or in addition, tensioners may be provided in the standing rigging or running rigging, or both, to provide the required initial tensioning.
There may be bodily adjustment of the position of the mast in the longitudinal direction of the craft, if desired.
An embodiment of the present invention will now be described by way of example with reference to the accompanying drawings in which:
FIG. 1 is an elevation from the stern of a monohull sailing craft embodying the present invention, and showing a mast of the craft in its normal, upright position;
FIG. 2 is a further elevation from the stern of the craft, but showing the mast in a heeled condition;
FIG. 3 is an enlarged part sectional elevation of the mast of the craft shown in FIGS. 1 and 2;
FIGS. 4, 5, 6 and 7 are enlarged detailed views respectively on lines 4--4, 5--5, 6--6 and 7--7 of FIG. 3;
FIG. 8 is a detail view of a pivotal mounting of the mast;
FIG. 9 is a section on line 9--9 of FIG. 8,
FIG. 10 is a simplified perspective view of a multimasted craft in which the masts are able to heel independently of one another, and
FIG. 11 is a simplified perspective view of a multimasted craft in which the masts heel together.
In this embodiment the invention is applied to a small single-masted sailing craft. The craft has a hull 10 and a mast 11, preferably of tubular metal construction, which is pivoted at its foot by a pivoted mounting 12 to the hull 10 close to the level of the deck 13 of the hull. The pivotal mounting 12 allows the mast 11 to heel relative to the hull 10, both to port, as shown in FIG. 2, and to starboard. Fixed fore-and-aft stays, not shown, connected to the top of the mast by swivels and to the prow and stern of the hull, also by swivels, support the mast against fore and aft strains. At each side, the mast, as shown in FIG. 3, is supported by a combination of standing rigging 14 and running rigging 15, which with a resilient tensioning device 16 to which the running rigging is connected, also automatically control the heel of the mast according to wind forces acting on sails or vanes, not shown, supported by the mast.
The standing rigging 14 at each side of the mast is formed by a pair of shrouds 17, FIG. 4, each fitted at the lower end with a turnbuckle 18 connected to a strong, closed helical tension spring 19 which hooks into one of a series of holes 20 in one flange of an angle section metal bracket 21 which is secured to the deck 13 of the hull near the side of the hull, or alternatively to the side of the hull, or to the gunwale of the side. The upper ends of each pair of shrouds 17 are connected to opposite ends of a spindle 22, FIG. 5, journaled in and extending transversely between the outer end portions of one of two pairs of parallel arms 23 extending from opposite sides of the mast 11, and pivoted at their inner ends about a horizontal axis to a bracket 24 clamped to the mast approximately halfway up the mast. The two pairs of pivoted arms 23 constituted crosstrees. For strengthening purposes the outer ends of the pivoted arms 23 of each pair are connected together, beyond the spindle 22, by a crosspiece 25. The ends of the spindle 22 journaled to each pair of pivoted arms 23 project beyond the sides of the arms and the connection of the upper ends of the shrouds 17 to the spindle is made outside the arms. There is allowance for relative rotation between the ends of the shrouds and the spindle 22.
The running rigging 15 at each side of the mast is formed, as shown in FIG. 3, by a cable stay 26 which is connected at one end to the spindle 22 between the pair of pivoted arms 23 at the same side of the mast. Spacer sleeves 27, FIG. 5, fitted on the spindle 22 each side of the connection of the end of the stay 26 to the spindle, keep the end of the stay spaced centrally between the pair of pivoted arms 23. From the spindle 23 the stay 26 extends upwards and over a pulley 28, or sheave, FIGS. 3 and 5, supported by a bracket 29 clamped to the mast near its upper end. Each pulley 28 is mounted between a pair of U-shaped carrier arms 30 connected to the brackets 29 which project laterally to the side of the mast. The carrier arms 30 are joined laterally outwardly of the pulley by a crosspiece 31 for strengthening purposes. The pulley 28 can be adjusted laterally of the carrier arms 30 to some extent to alter the distance by which it is spaced from the mast. This is made possible by aligned horizontally extending slots 32 in the two carrier arms 30, and a headed bolt 33, FIG. 5, which forms the pivot pin of the pulley 28 and passes through, and can be moved along, the slots and is fitted with a nut 34 to secure the bolt, and thus the pulley, in any adjusted position. After passing around the pulley 28 the stay 26 extends downwards alongside the mast 11 and is fitted at its other end with a swivel 35 which is connected to a tensioner 36, which is in turn connected to the resilient tensioning device 16. By suitable lateral adjustment; if necessary, of the position of the pulley 28 on the carrier arms 30, the downward run of the stay 26 is set so that it extends parallel to the mast.
Each tensioner 36, as shown in FIG. 6, comprises a shackle 37, to which the swivel 35 is attached, a pair of eye-ended links 38, the eyes at the upper ends of which are connected to the shackle 37, and the eyes at the lower ends of which are connected to opposite ends of a bar 39 having an internally threaded hole at the center of its length into which is screwed the upper end of a vertically extending screw-threaded spindle 40 of the associated resilient tensioning device 16.
Each resilient tensioning device 16 comprises, as shown in FIGS. 3 and 7, an open substantially rectangular housing 41 formed from upper and lower horizontal, reinforced metal plates 42 and 43 respectively, each bolted at one end to one of two clamping brackets 44, by which the housings 41 of both tensioning devices are rigidly clamped to the sides of the mast, and inner and outer vertical, metal channel members 45 and 46 respectively, the inner channel member 45 being bolted at its ends to the brackets 44, and the outer channel member being bolted to the free ends of the upper and lower plates 42 and 43. If desired, the plates 42 and 43 may alternatively be welded or brazed to the clamping brackets 44, and similarly the inner and outer channel members may respectively be welded or brazed to the clamping brackets and the upper and lower plates 42 and 43. In the housing 41 is a metal floater plate 47 which extends horizontally between and engages at its ends in vertically elongated guide slots 48 in the inner and outer channel members 45 and 46. The guide slots 48 allow the floater plate 47 to move up and down in the housing 41. The screw-threaded spindle 40 previously mentioned passes through a central plain hole 49 in the upper plate 42, and at its lower end through a plane aperture 50 in the floater plate 47 aligned with the plain hole 49. Fitted around the spindle 40 between the upper plate 42 and the floater plate 47 is a strong, open helical compression spring 51 which is arranged to bear at its ends on those two plates, although normally it just rests on the floater plate and does not exert any downward loading on the floater plate. Underneath the floater plate 47, the spindle 40 is fitted with a plate metal washer 52, and has underneath the washer 52 an eye 53 to which is attached the upper end of a strong, main tension spring 54, attached at its lower end to an eyebolt 55 secured to the upper side of the lower plate 43. The main tension spring 54 normally acts to urge the spindle 40, and thus the downward run of the associated stay 26, downwards. On the underside of the floater plate 47 are secured four eyebolts 56, two each side of the aperture 50, to which are attached the upper ends of four closed, secondary helical tension springs 57, which extend parallel to, two each side of, the main tension spring 54, and are attached at their lower ends to four additional eyebolts 58 secured to the upperside of the lower plate 43. These four secondary tension springs 57 are individually weaker than the main tension spring 54, and they normally urge the floater plate downwards. The action of the compression spring 51, the main tension spring 54, and the secondary tension springs 57 will be described further hereafter.
The bottom of the mast 11 may simply be connected by a pivot pin to the pivoted mounting 12 secured to the hull, or it may be connected by a universal joint to the mounting to allow the mast not only to heel transversely of the hull but also in the other directions as well. Alternatively the pivot mounting 12 may take the form shown in FIGS. 8 and 9. In this the mast is supported at its foot by a pair of spaced coaxial, large diameter, gear wheels 59, as shown in FIGS. 8 and 9, keyed to, for rotation with, a pivot shaft 60 journaled in end wall plates 61 of a boxlike framework 62 which is rigidly secured underneath the deck 13 of the hull. The foot of the mast is held by a clamping bracket 63 which extends between, and is rigidly secured to the gear wheels 59 above the pivot shaft 60. The pivot shaft 60 extends in the longitudinal direction of the hull, and the keyed connection of the gear wheels 50 to the shaft allows the wheels to be moved axially of the shaft to alter the position of the mast longitudinally of the hull, for example as indicated in FIG. 8. The framework 62 supports the pivot shaft 60 only just below deck level. The framework 62 is rigidly bolted to the underside of the deck. If required, it may also be secured to frame members of the hull below deck.
The pivot shaft 60 provides the pivot of the mast, allowing the mast to heel transversely of the hull. As the mast heels it turns the shaft and the gear wheels 59. Mounted on each of two parallel shafts 64 below and to either side of the pivot shaft 60, are spur gears 65 which mesh with the gear wheels 59. These two shafts 64 are also journaled in the end wall plates 61 of the framework 62, and the spur gears 65 they carry can be adjusted axially of the shafts. Flexible or other drives, not shown, are coupled to the shafts 64 to take drive imparted to the shafts from the pivot shaft by heeling of the mast to operate and automatically adjust according to the heel, at least some of the trim gear of the craft, and/or sails or vanes, or self-steering gear of the craft.
Also supported by the framework each side of the pivot shaft are two hydraulic buffers 66 which extend towards the clamping bracket 63 holding the foot of the mast 11.
In use the mast is set up on the hull so that it extends perpendicularly of the hull. The turnbuckles 18 of the standing rigging 14 and the tensioners 36 of the running rigging are adjusted to tension the two sets of rigging as required, and to ensure that the mast is supported perpendicularly of the hull athwartship. The tensioning devices 16, acting through their associated running and standing riggings, hold the mast in the upright condition while wind forces on the sails or vanes carried by the mast are fairly light. While the mast is upright the pivoted arms 23 extend horizontally from the mast. The combined lengths of the shrouds 17 of the standing rigging and the strong tension springs 19 once set normally remain fixed, because the springs usually do not vary in length as they are provided solely for the purpose of damping sudden heavy shock loads on the rigging caused for example by unexpected gusting in severe squall conditions and heavy sea motion.
Under stronger wind forces the mast is automatically allowed to heel to leeward under the control of the standing and running riggings and the resilient tensioning devices 16. As the mast heels, about the axis of the pivot shaft 60, the standing rigging 14 on the windward side of the mast causes the pivoted arms 23 on that side of the mast to pivot downwards with respect to the mast, pulling the attached end of the cable stay 26 of the associated running rigging 15 downwardly with them, so that there is resultant upward movement of the run of the stay 26 which extends alongside the mast. This in turn causes the threaded spindle 40 of the associated resilient tensioning device 16, to move upwards relative to the housing 41. In the early stages of heel the upward movement of the spindle 40 is resisted and hence the extent of heel of the mast is controlled, only by the main tension spring 54 attached to the spindle 40. If the heel induced by the prevailing wind forces causes the spindle 40 to be moved upwards by the stay 26 sufficiently for the washer 52 at the bottom of the spindle to engage and move the floater plate 47 upwards in the housing 41, then the four secondary tension springs 57 also come into effect to help to control heeling of the mast. There is still further resistance to upward movement of the spindle, and heeling of the mast, if the heel of the mast is great enough for the stay to cause the spindle 40 to move the floater plate 47 upwards sufficiently for the compression 51 to come into effect and exert downward pressure on the floater plate. It will be understood from the foregoing that as the angle of heel of the mast increases the resistance to heel imposed by the various springs of the resilient tensioning device is progressively increased. When the wind forces decrease the action of the springs on the stay 26 automatically returns the mast to its normal upright position.
Slack in the standing and running rigging on the leeward side of the mast is automatically taken up by the resilient tensioning device on the leeward side of the mast. In fact all the slack may not be completely taken up as the angle of heel increases, but this in practice does not matter as long as there is not so much slack that there is risk perhaps of rigging hanging over the side of the hull and dragging in the water.
The pivoted arms 23 spread the rigging from the mast and provide lever motion as the mast heels, which enables smooth, steady heeling movement of the mast to be achieved, rather than sudden erratic movement, which is essential to obtain the full benefit of the present arrangement. The action of the pivoted arms on the rigging also allows the mast to return easily and smoothly to its normal, upright position.
A very wide range of heel is possible with the arrangement described and illustrated. Up to 70° heel has been achieved which in practice is about the maximum required because at that angle all wind is spilled from the sails or vanes carried by the mast. With large angles of heel there will be some heeling of the hull itself, but this will be comparatively small and certainly not sufficient for there to be risk of capsizing and for the change of wetted surface area and underwater shape of the hull to urge the craft to deviate excessively.
The strength of the springs incorporated in each resilient tensioning device are selected according to the extent of mast heel required to be allowed under particular wind forces, and according to the size and weight of mast and sail or vane area to be carried by the mast. In the drawings the springs of the devices are illustrated as being quite short, as the craft is small, but for larger craft longer and stronger springs may be substituted. To take longer springs the housings 41 may readily be extended by substituting longer inner and outer channel members 45 and 46 between the upper and lower plates 42 and 43 of the housing. Apart from modifications of this nature, the standing and running rigging, pivoted arms 23, pulleys 28 and resilient tensioning devices 16 may readily be interchanged between craft of different sizes. The fact that the pivoted arms 23, pulleys 28 and tensioning devices 16 are all attached by clamping brackets to the masts, enables them to be quite easily detached from the mast for fitting to the mast of another craft. They can also be easily fitted to an existing mast of a craft to replace the standard mast rigging. It would only be necessary to provide the mast with a pivoted mounted on the hull, which could be done relatively simply and without having to make extensive alterations to the mast and hull, particularly if a simple pivot of the form previously mentioned is used. Even using the pivoted mounting described and illustrated, however, not undue modification of an existing craft would be necessary to take the mounting. It would be possible, instead of positioning it below deck as described, to have it on top of the deck, which would then involve little or no modification of an existing hull.
It may be desirable, especially if the apparatus is to be applied to an existing mast, for padding to be inserted between the mast and the clamping brackets of the resilient tensioning devices, the pivoted arms 23, and the pulleys 28, to provide increased friction, and prevent scratch damage to the mast. If padding is used, then the quality of the finish of the parts of the brackets is not so critical as it would otherwise be, and hence the cost of their manufacture can be reduced to some extent. If the apparatus is subsequently removed from the mast, the mast can be easily returned to its original condition with the standard rigging.
If the apparatus is built into a craft the various brackets mentioned may be permanently fixed to the mast.
With the arrangement of the standing riggings, running riggings and tensioning devices described and illustrated, the tendency is for the mast to be lifted from the deck, which has the advantage of reducing the direct loading on the pivot of the mast. All the apparatus controlling heel of the mast is above deck.
The buffers 66 act as stops to prevent the mast heeling excessively, for example under gusting conditions. Where the maximum desired angle of heel in either direction is reached, the buffer 66 to the side of the mast to which the mast has heeled abuts against the bracket holding the foot of the mast. The buffers 66 also provide stops to complete collapse of the mast if the riggings should fail.
If desired, a braking action may be manually imposed upon the heel of the mast in either direction by means of a disc brake, not shown, which operates on the pivot shaft.
If the mast is repositioned bodily longitudinally of the hull, by moving it along the pivot shaft, as indicated in FIG. 8, the connections of the strong tension springs 19 to the bracket 21 can be appropriately adjusted by hooking the springs into different holes 20 of the bracket.
It will be appreciated that while the apparatus for automatically controlling heel of the mast has been described and illustrated as applied to a monohull sailing craft, the apparatus could readily be applied to a multihull craft.
With the present invention, counterweighting of the hull or hulls, heel or float of the craft to which it is applied, is not necessary to offset the effect of wind forces which in craft having a conventional, fixed mast normally cause heel of the craft rather than increased speed of travel. Hence the design of the hull or hulls, keel or float can be concentrated on reduction of the effect of wave motion, although some allowance may have to be made in the design to take into account the effect of the weight of the mast when the mast heels, this depending largely upon the size of the craft and the extent by which the mast is permitted to heel.
In FIG. 11 of the accompanying drawings there is illustrated a multimasted craft the masts 111 of which are pivotally mounted on the hull independently of one another so that they are able to heel independently of one another. Each mast 111 has its own individual pivoted mounting 112 which is similar to the pivoted mounting 12 described above and illustrated in FIGS. 8 and 9 of the drawings.
A multimasted craft is also shown in FIG. 12 of the drawings but in that craft the masts 211 are all mounted on and are keyed to for rotation with a single extended pivot shaft 260 so that they will all heel together. The manner in which each mast 211 is mounted on the extended pivot shaft 260 is substantially similar to that in which the single mast 11 described above is mounted on its pivot shaft 60.