This application is related to U.S. application Ser. No. 12/437,076, “Mast Track with External Headboard Car,” and U.S. application Ser. No. 12/437,062, “Sectionalized Mast Track,” both of which are being filed on the same day as the instant application. The subject matter of this application is also related to U.S. Pat. No. 6,371,037, “Sail Furling System,” to Cook et al. filed on Dec. 26, 2000.
The above-referenced applications and patent are incorporated herein by reference in their entireties.
Furling and reefing are separate, but related activities involving hoisting and lowering sails on yachts and sailboats. Furling is completely retiring a sail from use so that the furled sail no longer presents any cross section to the wind for driving the boat. Reefing, on the other hand, refers to reducing the sail area to provide less cross section to the wind, reducing the driving force of the wind on the sail. Since most furlers are also used as reefers, the terms are used interchangeably herein.
Before the advent of furlers, at least two people were needed to hoist and lower the sails on larger yachts. Prior art furlers are intended to allow a single person to hoist and lower sails on large yachts, even those longer than 40 feet. Many of the first mainsail furlers were mast furlers designed to furl the mainsail within the mast, allowing the lower edge, or foot, of the sail to slide along the boom toward the mast as the sail is furled. Unfortunately, mast furlers increase the weight aloft, affecting the stability of the vessel under sail. Mast furlers are also difficult to maintain, as fixing even simple malfunctions, such as jams, requires someone to go aloft, a dangerous and time-consuming activity.
Boom furlers, on the other hand, are configured to furl the sail inside the yacht's boom, which extends perpendicularly from the mast at the foot of the sail. Depending on the configuration, the foot of the sail may be attached to the mandrel along its length or attached only at the tack and clew (i.e., the forward and aft corners along the foot of the sail). A winding cord attaches the sail to a drum inside the boom. Rotating the drum causes the sail to wind (or unwind) around a mandrel inside the boom. Because the boom furler is close to the deck, boom furlers are easier to maintain than mast furlers and do not affect the stability of the yacht.
Unfortunately, most boom furlers must be installed apart from the mast, creating a space between the mast and the furler where the sail deforms. This deformation tends to increase when the sail is wound down, causing folds in the ends of the winding. In addition, this configuration increases stress on the bolt rope, which is sewn into the sail to aid in feeding the sail into the boom or mast. Increased stress on the bolt rope makes it more difficult to wind or unwind the sail.
Prior art solutions described in U.S. Pat. No. 5,697,314 to Clausin include using pulleys to offset the drum or relieve stress on the bolt rope. Pulleys introduce friction, making it difficult to wind and unwind the sail; they also require linkages that must remain taut. Clausin also discloses a recessed bolt rope slot and bolt rope guide that relieve stress on the bolt rope. U.S. Pat. No. 4,236,475 to Merry teaches a simpler, two-pronged metal guide for aligning the bolt rope with mast, preventing the bolt rope from jamming as the sail is raised or lowered. Neither of these bolt rope guides is sufficiently strong to handle the stresses of larger sails, such as those used on yachts of 40 feet or more in length.
Embodiments of the present invention include an articulating sail feeder and method for using an articulating sail feeder for a yacht. Example articulating sail feeders include herein called “hinge tracks” arranged in an articulating column with a longitudinal axis substantially parallel to a mast of a yacht, where the hinge tracks are configured to receive a sail luff. Herein referenced “limiting pins” and ball joints in the articulating column enables lateral and rotational movement of the sail. The limiting pins, which are pins disposed between respective pairs of adjacent hinge tracks, limit the movement of a given hinge track with respect to a neighboring hinge track and thus are referred to herein as “limiting pins”. The ball joints, which are also disposed between respective pairs of adjacent hinge tracks, receive a tensioning line that runs along the longitudinal axis of the articulating column.
In certain embodiments, the articulating column enables the sail to move and rotate freely in a lateral direction with limited axial twist as the sail is being furled or reefed. This free rotation may be achieved using limiting pins formed of two frustums, or truncated conical sections, that are placed base-to-base and separated by a flange. The slope of the frustums determines, in part, the range of motion and may allow universal axial motion.
The articulating column's range of motion may also be adjusted using the tensioning line, which may be a flexible wire, cable, rod, or synthetic rope. Embodiments of the articulating sail feeder include means for adjusting tension of the tensioning line, such as wrenches or hydraulic cylinders. The means for adjusting tension of the tensioning line may be situated at either end or both ends of the tensioning line.
The hinge tracks may have a cross section comprising a batten guide, or luff extrusion, formed of two substantially parallel batten guide arms. A luff passage connects the batten guide to a luff rope slot formed forward of the batten guide. Example luff extrusions may include a channel configured to guide a headboard car along an axis substantially parallel to the long axis of the mast.
The articulating sail feeder may be configured to be coupled to a mast track for a yacht, such as a sectionalized mast track. Sectionalized mast tracks may include multiple mast track sections arranged in a column configured to be attached to a mast. Each mast track section may include an upper receiver and a lower receiver, both of which may be oriented along the longitudinal axis of the column. Neighboring mast track sections may be secured using respective securing pins configured to be received by a lower receiver of one mast track section and an upper receiver of the adjacent mast track section.
The foregoing will be apparent from the following more particular description of example embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the present invention.
A description of example embodiments of the invention follows.
The sail 30 shown in
Full battens 32 support roach 42, the sail area that lies outside a straight line from the head 38 to the lower aft corner, or clew 39, of the sail 30. Typically, the supporting battens 32 are about three times longer than the roach 42 that they support. Roach 42 enhances sail performance by adding 15-30% more sail area to a triangular sail, such as the sail 30 shown in
Unfortunately, full-length battens 32 reduce the life of the sail 30 by chafing against the batten pockets 34. The same forces that pull the sail 30 taut to propel the yacht 10 push the battens 32 towards the mast 20, causing the battens 32 to chafe against the batten pockets 34. Eventually, this chafing causes the battens 32 to tear or poke through the forward ends of the batten pockets 34. Reinforcing the batten pockets 34 alleviates this problem on vessels with smaller sails, but reinforcement is not sufficient to withstand chafing due to the larger compressive forces exerted on battens 32 in larger sails. In addition, compression increases friction on the sail slides that run in mast tracks 24 and in articulating sail feeders 80 without headboard cars 28, making it difficult to raise, lower, or reef the sail 30.
An articulating sail feeder 80 coupled to the bottom of the mast track 24 limits the sail's range of motion as the sail 30 is fed into the boom 26 by a boom furler (not shown), making it easier to reef and furl the sail 30. In yachts 10 without the present inventive articulating sail feeder 80, the sail 30 deforms in the space above the boom 26 during winding, causing folds in the ends of the winding. The articulating sail feeder 80 moves with the sail 30 as the sail 30 is being furled or reefed, preventing deformation and relieving stress on the bolt rope (not shown), which is sewn into the edge of the sail 30 to prevent fraying. The articulating sail feeder 80 allows the sail 30 to move and rotate freely from side to side (i.e., laterally), while preventing the sail from twisting too much around an axis parallel to the long axis of the mast 20.
The articulating sail feeder 80 flexes and twists as the sail 30 is wound down, reducing deformation of the sail 30 and eliminating folds in the ends of the winding. The articulating sail feeder 80 also reduces stress on the bolt rope by flexing and bending, making it easier to wind or unwind the sail 30. In addition, the articulating sail feeder 80 may be configured to enable limited twist or rotation about an axis parallel to the longitudinal axis of the mast 20 as the sail 30 is furled or reefed. The articulating sail feeder 80 may also flex fore and aft (i.e., in the plane of the page) or abeam (i.e., into and out of the page).
A feeder 82 at the bottom of the articulating sail feeder 80 guides the sail 30 into and out of the articulating sail feeder 80, which includes several track members herein called hinge tracks 84 arranged in a column between the feeder 82 and the bottom edge of the mast track 24. A threaded tensioning line 86 runs through the hinge tracks 84 along the interior of the column. A nut 88 secures the lower end of the tensioning line 86 in a bottom hinge track 85. Adjusting the nut 88 changes the tension of the tensioning line 86, altering the articulating sail feeder's range of motion.
As shown in
The cone angle of the sides of the frustums 91 and 93 fixes the maximum bend angle between adjacent pairs of hinge tracks 84, preventing the articulating column 81 from bending too much in one direction or another. Because the limiting pins 90 are symmetric about the longitudinal axis of the column 81, they permit universal axial motion (i.e., rotation) about the longitudinal axis of the column 81.
Each ball joint 94 is disposed between a respective pair of neighboring hinge tracks 84 in seats 344 aft of the limiting pin recesses 340 and forward of batten guides 302 shown in FIGS. 3B and 6A-C. The ball joints 94 receive a tensioning line 86 that runs through the column 81 via holes along the diameters of the ball joints 94.
The tensioning line 86 may be a flexible wire, cable, rod, synthetic rope, or any other suitable line or cable. As shown in
FIGS. 3B and 6A-C show the cross section 300 of the hinge of a hinge track 84; this cross section 300 is also known as a luff extrusion. A hinge track 84 with the luff extrusion cross section 300 shown in
The hinge track cross section 300 includes a pair of substantially parallel batten guide arms 304 that form the batten guide 302. A luff passage 306 connects the batten guide 302 to a luff rope slot 308 configured to hold a luff rope sewn into the luff 36 of the sail 30. As wind fills the sail 30, compressing the battens 32 (
The cross section 300 also includes a hinge pin tunnel 340 configured to receive limiting pins 90 and a ball seat 344 configured to receive ball joints 94. Each hinge track 84 has a connector tunnel 342 that connects the upper and lower ball seats 344, as shown in
As shown in
In a preferred embodiment, the hinge tracks 84 are each about five and a half inches long, about two inches high, and vary in width from just under two inches just forward of the headboard car channel 28 to about one and a quarter inches at the channel 28 itself. The headboard car channels 310 are each about seven-eighths of an inch wide and about one-quarter inch deep. The batten guide arms 304 are just under one and three-quarters inch long, forming a batten guide 302 of same length and a width of about one inch. The luff passage 306 may be about one-fifth of an inch wide and about one-quarter of an inch long. The luff rope slot 308 has a radius of about three-tenths of an inch. Edges of hinge tracks 84 with the present inventive luff extrusion cross section 300 may be beveled, chamfered, and/or radiused as appropriate.
The cavity 185 accommodates tensioning means attached to the lower end of the tensioning line 86 for adjusting the tension of the tensioning line 86. For example, the tensioning means may include a nut 88 (
The hinge tracks 84 and bottom hinge track 85 may be fabricated of carbon fiber, 6005 aluminum alloy, or any other suitable material. Generally, suitable materials are at least moderately strong; capable of bending, flexing and twisting; suitable for machining, welding, and brazing; and corrosion resistant (or able to be treated or coated with corrosion-resistant material). For example, the hinge tracks 84 may have a clear anodized finish. Hinge tracks 84 and bottom hinge tracks 85 may be made by machining, extrusion, or any other suitable manufacturing technique.
Because the headboard car 28 travels smoothly along the bearings between the channels 460 and 310, the sail 30 can be raised and lowered with a halyard (not shown) attached to the headboard car 28. In contrast to conventional sails, which are raised with halyards attached directly to the head 38 or the headboard 29, sails 30 coupled to headboard cars 28 in embodiments of the present invention do not need sail slides to ensure smooth travel of the sail up and down the mast. As a result, sails 30 raised with headboard cars 28 configured with luff extrusions 300 of the present invention do not suffer from the compression- and torque-induced friction that locks sail slides into place.
In a preferred embodiment, the headboard car 28 is made of aluminum or any other suitably strong, light, and corrosion-resistant material. The guide 452 is wide enough and long enough to substantially accommodate the luff extrusion 300. For example, the arms 454 may be about five inches long and spaced about two inches apart. The edges of the headboard car 28 may be beveled, chamfered, and/or radiused as appropriate.
The batten guide 502 receives battens 32 sewn in the sail below the headboard car 528. As compressive forces push the battens 32 forward, the battens 32 push against the batten guide 502, rather than chafing against the forward edges of the sail bolt rope. Similarly, the batten guide arms 504 hold the battens 32 as the battens 32 twist and rotate, reducing friction between the battens 32 and the respective batten pockets 34.
The alternative cross section 500 also includes a connector tunnel 542 and a hinge pin tunnel 540, which are configured to retain a tensioning line 86 and limiting pins 90, respectively. The connector 542 may also be configured to receive ball joints 94 with a ball joint seat (not shown).
Of course, other configurations of headboard car channels are possible. For example, the headboard car 28 could ride on channels formed by everted channels, protrusions, or rails that stick out from a mast track 24 with the inventive luff extrusion cross section. The channels may include more than two channels on each side, or may be formed further forward or aft along the inventive luff extrusion. The channels may be integral to the cross section or may formed by additional fixing parts to the mast 20 or mast track 24.
While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
For example, the generic term yacht as used herein includes sailing vessels, boats, and ships of various sizes, including mega-yachts, which may be 40 feet or longer. Similarly, the generic term sail includes mainsails, which are used primarily to propel yachts. Likewise, the generic term mast includes mainmasts and other masts. In addition, the terms luff rope, sail bolt rope, and bolt rope may be used interchangeably.
Further, the various dimensions, materials, and surface or edge processing are for purposes of non-limiting illustration. Other dimensions, materials, and manufacturing processing are suitable.
Number | Name | Date | Kind |
---|---|---|---|
3058138 | Tomlinson | Oct 1962 | A |
3331348 | Dyer | Jul 1967 | A |
4228755 | Graham | Oct 1980 | A |
4236475 | Merry | Dec 1980 | A |
4597347 | Spanopoulos | Jul 1986 | A |
4821664 | Dahmen | Apr 1989 | A |
5127351 | Breems | Jul 1992 | A |
5305700 | Strong et al. | Apr 1994 | A |
5546881 | Frederiksen | Aug 1996 | A |
5697314 | Clausin | Dec 1997 | A |
6145460 | Brookes | Nov 2000 | A |
6371037 | Cook et al. | Apr 2002 | B1 |
6575108 | Lindström | Jun 2003 | B1 |
Number | Date | Country | |
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20100282152 A1 | Nov 2010 | US |