Patent Application
20190176947
This application is a nonprovisional application and does not claim priority to any application.
Exemplary embodiments of the present invention relate to an apparatus capable of raising and lowering sails.
Sailing is an activity many partake in for both leisure and sport. One concern universal among all sailors is safety. A sailor must be prepared for the possibility of the boat capsizing anytime the ship is in open water. A ship may capsize for a variety of reasons, but it typically occurs from strong winds and large waves hitting the hull and sails at the proper angle to push the boat past its tipping point. One way to increase the stability of a boat is to lower its center of gravity. With a lower center of gravity, the ship becomes less susceptible to capsizing in dangerous conditions and has the ability to return to an upright position much easier.
One way to lower a ship's center of gravity is to lower the sails. Lowering the sails not only limits the effect the wind can have on a ship but also shifts weight towards the hull resulting in a lower center of gravity. Ships that include a mainsail have been adapted to furl the mainsail toward the hull. However, even more benefit exists if the headsail or jib is allowed to furl toward the hull. Any ship containing a furling headsail would typically wrap around the stay supporting the sail, not furling toward the hull. While this would eliminate the effect winds have on the sail, this stay furling would do little to affect the center of gravity of the ship. Furthermore, if a sailboat does capsize, the blade-furled headsail becomes weighted by water and acts an anchor or inverse keel below the ship, preventing the ship from turning upright.
There exists a need for a device capable of lowering the center of gravity of a ship by bringing the headsail towards the hull. The present invention seeks to remedy this need.
The present invention may be referred to as a headsail roller-furling boom, but this designation is in no way meant to limit the invention. The invention may be applied to other sails besides the headsail and may utilize various means of raising and lowering a sail beyond a roller-furling boom. Therefore, it is the intent of the applicant to only limit the invention as through the scope of the claims.
One object of the present invention is to allow the headsail to roll and furl downward toward the deck of the ship. To accomplish this, the sailboat may require a movable stay that will maintain substantially the same angle and tension as the headsail furls. This stay may be connected to a mast and the hull of the boat such that the angle created between the stay and the deck is substantially the same angle between the leading edge of the sail and the foot of the sail. This stay may be connected to a boom located on the hull. As the sail furls towards the hull, the sail may gradually and completely roll into the boom.
The present invention may be used to keep a boat's center of gravity at its lowest point, assisting in righting a ship when knocked-down in a storm or capsized. The weight of a furled sail near the hull provides a much lower center of gravity than a blade-furled sail. Furthermore, the invention may also be partially furled downward, providing for a lower center of gravity while still allowing for some wind to contact the sail. A partially furled sail kept towards the hull and near a mast will provide a larger measure of safety than a partially furled sail around a stay.
In addition to providing a lower center of gravity, the headsail roller-furling boom will eliminate the need to deploy an emergency storm triangle driving sail. Instead of requiring the sailor to go forward on a pitching deck in harsh conditions, the sail may instead be lowered to create a small triangle sail near the mast, effectively accomplishing the same function as a storm triangle sail. Another benefit is the ability to douse the jib or headsail quickly and shift sail pressure balance towards the deck and mast. Before this invention, this type of pressure balance shift could only occur with a boom-furling mainsail and only from the fore direction. With this invention, both fore and aft driving forces are exerted closer to the deck and mast.
The roller-furling boom may require a moveable stay to effectively raise and lower the sail. For a sail to perform properly, the stay the sail is attached to must remain rigid while the sail is deployed. It is important that the stay remain rigid and tension remains constant as the stay descends the mast and rolls into the boom. This may be accomplished by incrementally controlling the furl of the sail. Precise increments will allow the stay to maintain the same angle regardless of the amount the sail is deployed. For example, if a mast is 20 feet tall and the boom is 5 feet long, for every 4 feet the stay descends upon the mast, the stay should slide towards the mast inside or along the boom 1 foot. The same ratio should be maintained throughout any deployment or furling of the sail.
One embodiment will allow the sail to be incrementally raised and lowered using a ratchet and pawl gear system. This ratchet and pawl may be located at the mast and mechanically connected to the boom through use of a pulley system. Each notch of the ratchet may move the sail up or down a fixed distance. The pulley system may be configured to adjust the location of the stay at the boom to maintain the same stay angle, consequently changing the location of the tack along the boom proportional to the changing height of the leech along the mast. Although a single crank may be used to adjust both the height of the leech and foot of the sail, other embodiments may allow for separate controls of each, providing an alternative option for more experienced sailors to control the sail through feel and touch.
The foot of the sail, from tack to clew, may be mounted on a mandrel or turning spindle. The foot may be connected to the mandrel through the use of straps wrapped around the cylinder and fixed with connector pins. As the sail deploys or furls, the sail may unwrap or wrap around the mandrel or turning spindle within the boom. If the horizontal movements and vertical sail-mast movements are controlled with separate mechanisms, the sailor may have to ensure the movements are proportional to prevent the sail from bunching or jamming within the boom. A furling drum may be mounted at the aft end of the mandrel to capture a furling line as the sail is lowered or to release the stay as the sail is deployed.
In one embodiment, the stay may remain permanently fixed to the sail even as the sail completely furls. This would allow the stay closest to the deck to wrap around the outer edge of the sail within the boom. Other embodiments may provide a device for stay collection, such as a furling drum. For embodiments with some method of stay collection, the sail may connect to the stay as the sail deploys. This connection may occur through the use of hanks, clamps, shackles, rings, or any other similar mechanism.
Because the stay connected to the jib or headsail may move up and down the mast, the sailboat may employ the use of an additional stay—an immobile forestay. This forestay may be needed to properly secure the mast. A sailboat using this invention may have three or more stays, a mainstay, forestay, and sailstay. This forestay may utilize a furling blade or standard hank-on driver sail, while the sailboat as a whole still obtains the benefit of a furled sail from this invention on the staysail.
The boom may be swivel-mounted to the deck allowing the sail to tack both port and starboard. The boom may utilize manual tacking or self-tacking through use of a self-tacking traveler. The boom may support a staysail or standard working jib of 100% or less (all parts of the sail and boom remaining forward of the mast). The jib may also be used as the sole headsail management system of the boat where sail systems of 100% or less are frequently employed.
Some embodiments of the invention may utilize automatic furling of the sail for even more safety. The sailboat may have a sensor installed capable of determining when the sailboat goes beyond 90 degrees of pitch (bow down or transom down) or roll (mast in water). The sensor may be electrically communicating with an electric or powered winch. Once the sensor determines the ship is beyond the threshold limit, the sails may automatically retract and furl back into the boom, moving the sail canvas toward the hull and mast. The automatic furling will allow the ship to have some corrective measures in place regardless of the location of the sailor. Furthermore, the furling can occur when the sailor is unable to manually begin the furling process either because the sailor is not located at the proper winch or because an unexpected wind or wave caught the sailor off-guard. Although the 90-degree threshold may be used as a last resort, the sensor may also be set for a lower angle to prevent capsizing. For example, the threshold angle may be set to 70 or 80 degrees to automatically furl before the sailboat has been knocked down. Furthermore, this lower angle may be used as a good teaching mechanism for aspiring sailors. The threshold angle may be set to 50 or 60 degrees while a beginner is learning to further prevent any capsizing.
Various embodiments will allow for alternative forces to drive sail positioning. For example, the sail and boom system may be connected such that the only driving force is an upward pulling force from the head of the sail. The rest of the movements, either horizontally along the boom or downward during furling may be effectuated by springs, gears, pulleys, gravity, or any other similar method. This may be accomplished by having a system at rest, sail completely furled and no components moving, exert horizontal forces along the boom towards the mast and vertical forces down the mast toward the deck. Although the entire movement system may allow for a single force to control all movements, other embodiments may control all of the separate movements from separate forces. For example, vertical mast movements may require a separate force than horizontal boom movements, each of which may be effectuated by the sailor manually.
Various embodiments of the invention will now be described in detail with reference to the accompanying drawing. These figures are merely provided to assist in the understanding of the invention and are not intended to limit the invention in any way. One skilled in the art will recognize that various modifications and changes may be made to any of these example embodiments without departing from the scope and spirit of the present invention.
Referring to
Referring to figure two, three images of a sailboat are depicted to demonstrate the furling of the sail. As the jib 210 begins to furl into the boom, the contact point between the stay and the mast may move down the mast from 210 to 212 to 214. As the mast point 210, 212, 214 moves down the mast, the contact point between the stay and the boom located at the collar 216 will begin to proportionally move along the boom from 216 to 218 to 220. The stay movements at both the mast point 210, 212, 214 and contact point 216, 218, 220 will remain consistent and proportional to one another such that the sail angle 222 remains constant throughout furling.
Referring to
The boom 314 may have a drum 320 located at the aft end of the boom 314 near the mast 318. This drum 320 may be connected to a series of pulleys 322 to help facilitate the furling and deployment of the sail 310. The drum 320 and pulleys 322 may also be in connection with gears that will be configured to adjust the stay movements proportionally to keep the same stay angle throughout. The pulley system 322 may run either underneath or within the boom 314. The pulley system 322 may also run underneath the deck 324 to complete the connection with the stay for vertical stay movements along the mast 318. By running the pulley system 322 below the deck 324 and up through 326 the mast 318, excess exterior ropes will not pose a tripping hazard to the sailor. Any drum 320, gear, or pulley system 322 may utilize a series of mechanical locks or pins to prevent undesired furling or deployment.
The boom 314 may also have a collar 328 located at the contact point between the boom 314 and the stay 312. This collar 328 may connect with the pulley system 322 and slide along the boom 314 as the sail 310 furls or deploys. The collar 328 may also act as a rigid point of contact for the stay 312 to ensure proper tension is retained in the stay 312 throughout the furling or deployment process. Referring to
Instead of using a forward slotted mast, a collar 510 may also be used to facilitate the raising and lowering of a sail. This collar 510 may ride up and down the mast 512 with the contact point being ball bearings 514 to reduce friction. The stay may be connected to the collar 516 instead of a slot within the mast. The collar 510 may then be attached to halyards 518 for raising and lowering. The collar 510 may only wrap around the mast 512 about 75% 520 to leave room for the mainsail connected to the mast on the stern side.
Referring to
Referring to
Any embodiment of the present invention may include any of the optional or exemplary features of the other embodiments of the present invention. The exemplary embodiments herein disclosed are not intended to be exhaustive or to unnecessarily limit the scope of the invention. The exemplary embodiments were chosen and described in order to explain the principles of the present invention so that others skilled in the art may practice the invention. Having shown and described exemplary embodiments of the present invention, those skilled in the art will realize that many variations and modifications may be made to the described invention. Many of those variations and modifications will provide the same result and fall within the spirit of the claimed invention. It is the intention, therefore, to limit the invention only as indicated by the scope of the claims.
