US3872816A

US3872816A - Rotatable stay for sail furling gear

Info

Publication number: US3872816A
Application number: US376443A
Authority: US
Inventors: Edmund A Cutts
Original assignee: Individual
Current assignee: CACUT Corp A CORP OF MD
Priority date: 1973-07-05
Filing date: 1973-07-05
Publication date: 1975-03-25
Anticipated expiration: 1992-03-25

Abstract

A rotatable stay for jib furling gear for a sailboat which is durable and easy to handle and store, comprising a chain formed of interlocking links wherein the maximum transverse dimension of the interior openings of the links is substantially equal to the thickness of the end loops of the adjacent links which pass therethrough whereby the torsional flexibility of the stay is minimized.

Description

United States Patent 1191 Cutts Mar. 25, 1975 ROTATABLE STAY FOR SAIL FURLING GEAR [76] Inventor: Edmund A. Cutts, Box 8, Oxford, Md. 21654 [22] Filed: July 5, 1973 [21] Appl. No.: 376,443

[52] US. Cl. 114/106 {51] Int. Cl B63h 9/10 [58] Field of Search 114/102, 106, 39, 114, 114/230; 59/84, 85, 89, 90, 92, 93

[56] References Cited UNITED STATES PATENTS 70,256 10/1867 Peterson 114/106 279,477 6/1883 Bellairs 114/114 1,517,346 12/1924 Crandall 59/86 Primary ExaminerTrygve M. Blix Assistant ExaminerStuart M. Goldstein Attorney, Agent, or FirmSchuyler, Birch, Swindler, McKie & Beckett [57] ABSTRACT A rotatable stay for jib furling gear for a sailboat which is durable and easy to handle and store, comprising a chain formed of interlocking links wherein the maximum transverse dimension of the interior openings of the links is substantially equal to the thickness of the end loops of the adjacent links which pass therethrough whereby the torsional flexibility of the stay is minimized.

9 Claims, 6 Drawing Figures PATENTEB HAR 2 5 I975 LII 2 mm F ROTATABLE STAY FOR SAIL FURLING GEAR BACKGROUND OF THE INVENTION This invention relates to apparatus for reefing and furling the sails of a sailboat. More particularly, this invention relates to a novel rotatable stay for sail furling gear.

It has become accepted practice to reef or furl a sail of a sailboat by winding the sail around a rotatable stay to which the luff of the sail is secured. Various arrangements for accomplishing this are illustrated in Holmes U.S. Pat. No. 3,602,180, Hood U.S. Pat. No. 3,611,969 and Britton U.S. Pat. No. 3,730,124. Typically, in such arrangements a heavy wire rope is sewn into the luff or leading edge of the sail. At the head of the sail, the wire rope stay is attached to a thrust bearing swivel which in turn is secured to a halyard which passes over a block affixed to the mast. At the tack of the sail, the wire rope stay is also connected to a thrust bearing swivel which in turn is secured to the deck of the boat. The tack swivel is provided with a rotatable drum around which a line is secured. When the line is pulled, the drum and the stay are caused to rotate around the longitudinal axis of the stay and the attached sail is wound around the stay. When the sail is completely wound around the stay, it is said to be furled. When the sail is only partially wound about the stay it is said to be reefed or shortened. Once the sail is wound there'- around, the stay is secured against undesired rotation by locking the drum in a given position while the upper thrust bearing swivel is left free to rotate.

Wire rope displays considerable torsional flexibility, and a wire rope stay undergoes considerable torsional flexion during furling or reefing inasmuch as the rotational-drive necessary to overcome the considerable resistance produced by the wind against the sail is all introduced at the lower end of the stay. Further, when the sail is shortened or reefed, the upper swivel may make several revolutions in either direction depending on which tack the boat is on or on variations in the velocity of the wind thereby subjecting the stay to additional torsional flexion. These torsional stresses to which the stay is subjected result in relatively rapid deterioration of the stay due to metal fatigue and eventually cause the stay to fail. Such continuous torsional stresses also may cause the halyard itself to part.

Since wire rope stays are commonly sewn into the luff of the sail, they also give rise todifticult stowage problems. It is impossible to fold the sail compactly for below deck storage because the heavy wire rope used for such stays normally cannot be coiled to a diameter of less than four feet. The magnitude of the difficulty caused by the inability to compactly fold such sails becomes clear when it is realized that most sailboat hatchways are under three feet wide. As a consequence,

these sails are always left rolled up and hoisted in place. This is a dangerous practice for when left unattended in a heavy wind, they may become unfurled and can cause extensive damage to the rigging and the boat.

In an effort to alleviate the problem of failure of the stays due to metal fatigue induced by the torsional flexion, some sail makers have made the sail stay out of solid rod. While stays of solid rod are able to better resist the torsional stresses than wire rope, the handling problems of such stays are much worse. The rods are much too long to let down on deck if the gear should 2 malfunction at sea and are utterly impossible to stow away belowdeck.

Also, because the wire or rod is usually permanently sewn into the luff of the sail, it is not possible to conveniently replace the sail on such a stay should the sail itself become torn or otherwise damaged or should it be desired to replace the sail with a sail of a different type.

Accordingly, it is an object of this invention to provide a rotatable stay forfurling and reefing the sail of a sailboat which is able to resist torsional stresses.

It is a further object of this invention to provide a rotatable stay for furling the sail of a sailboat which may be detachably connected to the sail.

It is another object of this invention to provide a rotatable stay which may be compactly stowed belowdeck.

It is a still further object of this invention to provide a rotatable stay for sail furling gear which may be used with several different sails.

SUMMARY OF THE INVENTION These and other objects of the invention are achieved by providing a rotatable stay for sail furling gear comprising a plurality of links each of which has a pair of opposed end loops and at leastone interior opening through which an end loop of at least one adjacent link is extended so that the links interlock to form a continuous chain one end of which maybe attached to rotational drive means mounted on the deck of a boat wherein the maximum transverse dimension of the interior openings of at least every other link of said chain is substantially equal to the thickness of the end loops of adjacent links which extend therethrough so that the chain will resist torsional flexion.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be further described with reference to the attached drawings wherein:

FIG. 1 is a side view of sail furling gear embodying the instant invention;

FIG. 2 is a transverse sectional view through the stay and associated sail shown in FIG. 1 taken along line FIG. 3 is a longitudinal section through the stay illustrated in FIGS. 1 and 2 taken along line 2;

FIG. 4 is a transverse sectional view of a second embodiment of the invention corresponding to the view illustrated in FIG. 2;

FIG. 5 is a side view partially in section of a third embodiment of the invention; and

FIG. 6 is a perspective view'of a link used in the embodiment of the invention illustrated in FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows furling gear generally designated by reference numeral 1 for the jib ofa sailboat. A jib 2 is secured to a rotatable stay 3 by fasteners 4 which engage grommets 5 placed along the luff 6 or leading edge of the jib. The upper end of stay 3 near the head ofjib 2 is secured to a thrust bearing swivel 7 which in turn is connected to a halyard 8 which passes over a block on the mast of the boat (not shown). The lower end of stay 3 near the tack of jib 2 is secured to a rotational drive means 9 which comprises a lower thrust bearing swivel 10 with a drum 11 secured to the upper portion 3-3 of FIG.

thereof. The lower portion of swivel is secured to a plate 12 fastened to the boat deck. A line 13 is passed around and secured to drum 11. One or more suitable blocks 14 may be provided for guiding line 13. The clew ofjib 2'is secured to a sheet 15 in the conventional manner. Also shown in FIG. 1 is a forestay 16 which provides support for the mast of the boat when stay 3 and the attached jib 2 are lowered by means of halyard 8. When line 13 is pulled, drum 11 is turned which causes stay 3 to rotate about its longitudinal axis so that jib 2 is wound therearound.

A first embodiment of the stay of the invention is more particularly illustrated in FIGS. 2 and 3. Stay 3 comprises a chain 17 of

continuous loop links

18 and 19.

Links

18 and 19 are formed respectively with

interior openings

20 and 21 and

end loop portions

22 and 23. The end loop portions 22 of links 18 each pass through the interior opening 21 of an adjacent link 19 and the end loop portions 23 of links 19 each pass through the interior opening 20 of an adjacent link 18 so that the links interlock to form a lineal chain 17. As shown in FIG. 3, the maximum transverse dimension of interior openings 20 of links 18 is substantially equal to the thickness of end loop portions 23 of links 19.

Because the size of openings 20 is not significantly greater than the thickness of end loops 23, such loops cannot twist with respect to links 18 about the longitudinal axis of the chain. Consequently, links 18 and 19 are locked against rotation relative to each other about the longitudinal axis of chain 17. However, the links remain free to turn about the other coordinate axes of the chain due to the curvature of the end loop portions.

As can be seen from FIG. 2, the transverse dimension of interior openings 21 of links 19 is somewhat greater than the thickness of end loop portions 22 of link 18. However, by eliminating substantially all longitudinal twisting between each link 18 and the adjacent links 19, longitudinal twisting of the entire chain 17 is substantially eliminated.

Chain 17 is encased in a snugly fitting, flexible sleevelike cover 24 which may be formed of any suitable material. In a preferred embodiment, cover 24 is an extruded tube of polyvinyl chloride. Cover 24 is for convenience in handling the stay; the cover prevents the links from collapsing or twisting about a transverse axis and keeps the links in uniform lineal position.

FIG. 2 further illustrates in greater detail how jib 2 is secured to stay 3. Fasteners 4 comprise snap hooks secured to selected links of chain 17 and extending through appropriate openings 25 in cover 24. These snap hooks are received through grommets 5 placed in the luff6 ofjib 2. Naturally, other types of fastening devices could be utilized to secure the sail to the stay. Fasteners 4 are merely exemplary of several releasable fastening means which can be used.

A second embodiment of the invention is illustrated in FIG. 4, and generally is identical to the embodiment illustrated in FIGS. l-3 except that the maximum transverse dimension of the interior opening of every link in a chain 17' of a stay 3' is substantially equal to the thickness of the end loop portions of the adjacent links which extend therethrough. Thus, the maximum transverse width of interior openings 21' of links 19' is substantially equal to the thickness of end loop portions 22 of links 18 so that chain 17' is doubly secured against torsional flexion.

FIGS. 5 and 6 depict a link configuration used in a third embodiment of the invention. Links 26 comprise a solid center portion 27 and opposed end loop portions 28 which form a pair of spaced interior openings 29 through the link. The maximum transverse dimension of openings 29 is substantially equal to the thickness of the end loop portions 28 of the adjacent links which pass therethrough so that each link 26 in chain 30 is locked against rotation relative to its adjacent links around the longitudinal axis of chain 30. Chain 30 has the advantage of maximum stabilization against torsional flexion, but also has the disadvantage of somewhat greater weight. Like the chains illustrated in FIGS. 1-4, chain 30 may be encased in a flexible sleeve-like cover if desired to increase handling convenience.

The rotatable stays of the invention are equal or superior to a solid rod in resisting torsional flexion around the longitudinal axis thereof, but are flexible in a transverse direction. For example, links of 3/l6 inch chain may be readily twisted into a coil of less than five inches in diameter. Further, the stays of the invention may be constructed so as to be readily detachable from the associated sails so that replacement sails or sails of a different type may be used with a given stay, and the sails and the stay may be readily stowed in a most compact manner.

The rotatable stays of .the invention are not limited to use with a jib, but may be used with any appropriate type of sail.

Modifications of this invention indoubtedly will occur to those skilled in the art, therefore the invention is to be limited solely by scope of the appended claims.

I claim:

1. A rotatable stay for furling a sail of a sailboat. said stay comprising:

a plurality of links, said links each having a pair of op posing end loop portions and at least one interior opening through which one end loop portion of at least one adjacent link extends;

said links being interlocked to form a linear chain having first and second ends, said first end being adapted to be attached through swivel means to a halyard on a mast of the sailboat, said second end being adapted to be attached to rotational drive means mounted on the deck of the sailboat; and

at least alternate links of said chain being formed such that the maximum transverse dimension of the interior openings of the links is substantially equal to the thickness of the end loop portions of the adjacent links which extend therethrough whereby the torsional flexibility of said chain is minimized.

2. A stay as recited in claim 1 wherein each of said links is formed such that the maximum transverse dimension of the interior openings of said links is substantially equal to the thickness of the end loop portions of the adjacent links which extend therethrough.

3. A stay as recited in claim 1 wherein each of said links comprises a single continuous loop.

4. A stay as recited in claim 1 wherein each of said links comprises a solid center portion and a pair of op- 9. A stay as recited in claim 1 wherein each link is formed with curved end loop portions; adjacent links being free to turn with respect to each other about a transverse axis without collapsing such that said stay can be twisted into a coil less than five inches in diameter whereby stowage of the stay below deck is facili-

Claims

1. A rotatable stay for furling a sail of a sailboat, said stay comprising: a plurality of links, said links each having a pair of opposing end loop portions and at least one interior opening through which one end loop portion of at least one adjacent link extends; said links being interlocked to form a linear chain having first and second ends, said first end being adapted to be attached through swivel means to a halyard on a mast of the sailboat, said second end being adapted to be attached to rotational drive means mounted on the deck of the sailboat; and at least alternate links of said chain being formed such that the maximum transverse dimension of the interior openings of the links is substantially equal to the thickness of the end loop portions of the adjacent links which extend therethrough whereby the torsional flexibility of said chain is minimized.

4. A stay as recited in claim 1 wherein each of said links comprises a solid center portion and a pair of opposed end loop portions.

5. A stay as recited in claim 1 further comprising fastening means on said chain for attaching said stay to the luff of a sail.

6. A stay as recited in claim 5 wherein said fastening means comprises a plurality of snap hooks adapted to engage grommets in the luff of a sail.

7. A stay as recited in claim 1 further comprising a snugly fitting flexible cover disposed about said chain.

8. A stay as recited in claim 7 wherein said cover comprises an extruded tube of polyvinyl chloride plastic.

9. A stay as recited in claim 1 wherein each link is formed with curved end loop portions; adjacent links being free to turn with respect to each other about a transverse axis without collapsing such that said stay can be twisted into a coil less than five inches in diameter whereby stowage of the stay below deck is facilitated.