Patent Application
20190263493
Some embodiments of the present invention relate to auxiliary sail systems for ships. Some embodiments of the present invention relate to auxiliary sail systems for ships that are mounted to be easily stowed or placed into an operating configuration.
Some embodiments of the present invention relate to auxiliary sail systems for ships that incorporate features allowing the sail area exposed to wind to be incrementally decreased. Some embodiments of the present invention relate to auxiliary sail systems for ships that incorporate features allowing the sail area exposed to wind to be rapidly decreased.
Sail on ships is an ancient technology. Historically at the advent of steam there were many hybrid sail/engine designs for ships built from scratch. There have only been a few attempts to reintroduce sail to conventionally powered merchant ships in recent times although the last commercial voyage of a fully sail driven ship was in 1957, to the best of the inventor's knowledge.
Some problems precluding practical implementation of ‘sail on conventional ship’ devices are the complexity of design, the expense and intrusiveness of installation, the lack of safety features to guard against sudden excessive winds, the obstruction that the device presents to the loading and unloading of cargo, and/or significant labour requirements for operating the devices. Further, known devices have not been designed with a view to retrofitting to existing ships, meaning that they can be installed only on newly constructed vessels.
There is a general desire for improved auxiliary sail systems for powered ships. It may be desirable to provide such systems wherein the auxiliary sails are securely mounted such that damage is avoided or minimized under the extreme conditions found at sea (e.g. in the open ocean). It may be desirable for an auxiliary sail system to easily and quickly be removed from an operational configuration to a stowed configuration, so that the regular dockside operations of the ship while it is in port are not impeded.
The foregoing examples of the related art and limitations related thereto are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.
The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements.
One aspect of the invention provides a rail-mounted auxiliary sail system for a ship, e.g. a cargo ship. A rail system is provided that extends around at least a portion of the perimeter of the deck of the ship. A plurality of sail units mountable and movable on the rail system are provided. The rail system includes a plurality of fixed mounting points to which a respective one of the plurality of sail units can be fixed for use as an auxiliary sail to help drive the ship.
In one aspect, each one of the sail units has a base that can be fixed to the fixed mounting points, at least two rollers or wheels mounted to the base to allow the sail unit to move along the rail system, a mast mounted to the base, and a sail unit. In some aspects, the sail unit is a roller-blind design of sail having an upper boom, a lower boom, and a square sail that can be raised and lowered to extend between the upper and lower booms. In some aspects, the sail is held in a fixed position with respect to the upper boom and the lower boom, the lower boom being rotatable so that the sail can be wound around the circumference of the lower boom. In the lowered configuration, the sail is wound about the lower boom, and the upper boom sits just above the lower boom. A reefing cable extends from a bobbin fixedly connected to the lower boom for rotation therewith to an upper portion of the mast and then to a top boom collar that is used to raise and lower the upper boom. In the lowered configuration, no or only a small portion of the reefing cable is wound about the bobbin.
In one aspect, to raise the sail, the upper boom is hoisted, for example using a hoisting cable supported from the top of the mast. The lifting of the upper boom unfurls the sail from the lower boom, causing the sail to be released and correspondingly causing the reefing cable to be wound round the bobbin as the top boom collar rises on the mast. To lower the sail, the upper boom is lowered, for example by allowing the hoisting cable to lower the upper boom. A corresponding force is exerted on the reefing cable causing it to both be unwound from the bobbin and to rotate the lower boom, so that slack produced in the sail as it is lowered is taken up and wound around the lower boom.
In one aspect, an automatic reefing safety feature is provided. A flex detecting cable is provided to detect flexion in the upper boom caused by a strong wind event. The flex detecting cable is connected to a damping member that absorbs the forces applied by the flex detecting cable during normal sailing operations. The damping member can be an inertia drum. During a strong wind event, the damping member cannot absorb the force applied by the flex detecting cable, and this force is transferred to actuate a lever that releases a latch that ordinarily secures a top boom cable drum against rotation. When the latch is released, the top boom cable drum is permitted to rotate, and the top boom cable that is connected to raise and lower the top boom is permitted to unwind or move with the rotation of the top boom cable drum to lower the top boom.
Once the force applied by the strong wind event subsides, the automatic reefing safety feature is no longer activated, and the latch is biased back to its ordinarily securing position to secure the top boom cable drum against rotation. Thus, in some aspects, the top boom cable drum is permitted to rotate once in response to a strong wind event. In some aspects, the circumference of the top boom cable drum about which the top boom cable is wound is equivalent to about 1/10th of the height of the mast, so that activation of the automatic reefing safety feature results in a reefing of the sail by 1/10th of its height.
In one aspect, a mast rotation release safety feature is provided. The mast is mounted on a rotatable platform that is ordinarily engaged with an engagement member operable to rotate the mast to its desired position. A sensing cable is attached to the mast to detect strong wind events that cause greater than a predetermined degree of flexion of the mast. The sensing cable is configured to actuate a mechanical switch once more than the predetermined degree of flexion of the mast is detected. In one aspect, actuation of the mechanical switch releases a weight that is configured to raise the rotatable platform out of engagement with the engagement member, to thereby allow the rotatable platform to freely rotate so that a sail affixed to the mast is permitted to be placed into a configuration parallel with the prevailing wind, to thereby rapidly release the force applied to the sail and to the mast.
In one aspect, a chain tensioner is provided to regulate actuation of the mechanical switch. A spring within the chain tensioner has a spring constant selected to damp ordinary forces applied by the sensing cable during normal sailing operations. Once more than a predetermined level of force is exerted by the sensing cable, the spring allows a retaining member within the chain tensioner to be forced into a locked position, which locks an activating finger into a rigid position that moves the mechanical switch to the actuated configuration. Movement of the mechanical switch to the actuated configuration moves a pin from a secured position to a release position to release the weight and thereby lift the rotatable platform out of engagement with the engagement member to allow the rotatable platform to freely rotate.
In one aspect, activation of the mast rotation release safety device triggers an automatic full reefing of the sail. In one aspect, the sail incorporates an automatic reefing safety system as heretofore described, and actuation of the mechanical switch by the mast rotation release safety device triggers the latch that ordinarily secures the top boom cable drum against rotation to be moved to its released configuration and held there. This allows the top boom cable drum to freely rotate for as many rotations as are required to drop the top boom, and hence the sail, to its fully lowered position.
In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed descriptions.
Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.
Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.
With reference to
Rail-mounted auxiliary sail system 100 provides fuel savings for ships with which it is used. Without being bound by theory, using theoretical sail area to displacement calculations and a model recently wind tunnel tested by the inventor, fuel savings as compared with running on a ship's existing engines alone were estimated to be up to 25%. It is believed that in some embodiments this may translate into a typical savings of fuel across a shipping route on the order of 10%. In some embodiments, rail-mounted auxiliary sail system 100 is used to assist in manoeuvring and/or stopping a ship.
In some embodiments, a plurality of sail units 102 are deployed along the sides of the hull of ship 101. In the illustrated embodiment of
The size and position of sail units 102 can be determined by one skilled in the art depending on the type of ship on which the sail units 102 are installed. The distance between adjacent pairs of sail units 102 must be sufficient to allow their booms to rotate fully without interfering with one another, e.g. in embodiments in which upper and lower booms 106, 104 have a length of approximately 15.6 m, a spacing interval of at least 16.5 m should be provided between adjacent sail units 102 to avoid interference therebetween.
In some embodiments, sail units 102 are rotated such that the array of sails formed thereby are erected in a chevron configuration, with all sails pointing inwards towards the bow as shown in
In the illustrated embodiment, sail units 102 are square rigged sails 108. In some embodiments, the square rigged sails 108 have a surface area of between 100 m2 and 300 m2, including any value therebetween, e.g. 120, 140, 160, 180, 200, 220, 240, 260 or 280 m2. In alternative embodiments, any desired sail surface area could be used. In alternative embodiments, any desired type of sail could be used in place of square rigged sails, for example aircraft-wing style sails, Flettner rotors, conventional sails, or the like.
As best seen in
Each sail unit 102 is supported for movement about the outer deck of ship 101 along a rail system 112. In the illustrated embodiment, rail system 112 has a top rail 114 that runs along at least a portion of the outer deck of ship 101, and a bottom rail 116 that extends parallel to and at a lower elevation than top rail 114. A plurality of fixed mounting points 200 are provided about rail system 112 so that sail units 102 can be secured in position for use at any desired mounting point 200.
As best seen in
As can be seen from
In the illustrated embodiment, sail units 102 are moved along rail system 112 using a rope system 126. In one example embodiment illustrated in
In one example embodiment, first, second and third ropes 128, 130 and 132 have looped ends 128A, 130A and 132A provided at each of their free ends, as best seen in
Rope system 126 is moved to move sail units 102 about the deck of ship 101 using a capstan 134 that is rotated by a motor 136 (
Rope system 126 is operated to move sail units 102 about rail system 112. In one example embodiment, sail units 102 are moved along rail system 112 so that they will not interfere with dockside operations. Sail units 102 can be moved at any suitable time to prepare for dockside operations, e.g. during the ship's run into port, or in the port itself.
To move sail units 102 about rail system 112, first rope 128 (which may be indicated by being of a particular colour to assist operators in correct use of rope system 126, e.g. black in one example embodiment so that first rope 128 is also referred to herein as black rope 128), is wound around capstan 134 and run around a portion of the perimeter of ship 101. Appropriate structural elements such as rollers 140, 141 are used at appropriate locations (e.g. about the stern of ship 101) to ensure that black rope 128 has a smooth path of travel about ship 101, e.g. as shown in
The first looped end 128A of black rope 128 is lashed to the first looped end 130A of second rope 130 (which may also be indicated by being of a particular colour to assist operators in the correct use of rope system 126, e.g. white in one example embodiment so that second rope 130 is also referred to herein as white rope 130) to form a continuous cable, e.g. as shown in
Sail units 102 are lashed to the black and white ropes 128, 130 using cinched straps that can be looped over horn cleats 148 provided at suitable locations on sail units 102, e.g. as shown in
To adjust the position of sail units 102 on rail system 112, for example to provide for dockside clearance, in some embodiments, a third rope 132 (which may also be indicated by being of a particular colour to assist operators in the correct use of rope system 126, e.g. yellow in one example embodiment so that third rope 132 is also referred to herein as yellow rope 132) is used. Sail units 102 can be coupled to yellow rope 132 to allow for their movement using simple webbing loop 142 in the same manner as described above to secure yellow rope 132 to the horncleat 148 of the relevant sail unit 102. Yellow rope 132 can then be used to gather sail units 102 on a first side of ship 101 closer together, allowing the sail units 102 on the second, dockside, side of ship 101 to be drawn around ship 101 and out of the way of desired dockside activities, as described in greater detail below for one example method of operation.
In one example embodiment of 19 sail units installed on a GD 575 ship, it is anticipated that the entire operation to clear the sail units from the dockside (referred to as a “curtain operation”) will not take more than 30 minutes for two crew members to complete.
In one example embodiment, a method of loading a plurality of sail units 102 onto a ship 101 is provided. The two bow doors 139 of the ship are opened as shown in
At the stern 122 of ship 101, as shown in
White rope 130 is drawn around the opposite side of ship 101 to meet black rope 128, e.g. out the starboard bow door 139, in a similar manner. In this example embodiment, white rope 130 is drawn down the starboard side 118 to the “S9” position to meet black rope 128. Both ropes 128, 130 are held slack on horn cleats provided on the assembly that supports capstan 134, or at any suitable location on the bow 124 of the ship until the crew can secure black rope 128 about capstan 134, and secure the looped ends 128A, 130A of black rope 128 and white rope 130 by lashing them together in any suitable manner.
The first looped ends 128A, 130A of black rope 128 and white rope 130 are lashed together at their meeting point, e.g. at the “S9” position in this example embodiment, in any suitable manner. In this example embodiment, the two ropes are lashed together using a hook-and-loop (e.g. Velcro™) strap 133. The slack in black rope 128 is taken up and wound round capstan 134, and the second looped end 128A of black rope 128 is coupled to the second looped end 130A of white rope 130 at the bow of the ship in any suitable manner, e.g. using a hook-and-loop strap 133 in this example embodiment. Thus, black rope 128 and white rope 130 form one continuous rope when their free looped ends 128A, 130A are lashed together in this manner.
Sail units 102 are spaced apart from each other along the sides of ship 101 by any suitable spacing distance 150 (
In this example embodiment, a first double ring marker is provided at the spacing distance 150 along white rope 130, i.e. at 16.5 m in this example embodiment. The combined black/white rope 128, 130 is drawn back on capstan 134 until the first double ring marker is drawn adjacent the point at which the sail units 102 are to be loaded on the rail system 112. In this example embodiment, the sail units are to be loaded at the S3 position (i.e. the third sail position from bow 124 along starboard side 118).
The sail unit 102 that will be located at the P1 position (i.e. the first position at the bow 124 of ship 101 on the port side 120) is loaded first at the S3 position, and is lashed to white rope 130 at the first double ring marker using a simple webbing loop 142 that is cinched over white rope 130 at its securing end 144 and secured to the P1 sail unit 102 by securing the free end 146 of webbing loop 142 about the horncleat 148 provided on the P1 sail unit 102.
The length of simple webbing loop 142 is selected to be sufficient to provide sufficient play (i.e. freedom of movement) of sail unit 102 so that it can be moved along rail system 112 and into the desired position about ship 101. For example, it is anticipated that in many embodiments, webbing loop 142 will need to provide sufficient play to allow each sail unit 102 to be moved around the corners at the stern 122 of ship 101.
With the P1 sail unit 102 secured to white rope 130 at the first double ring marker, the P1 sail unit 102 is drawn along rail system 112 on starboard side 118 towards stern 122 by the desired spacing distance 150 relative to the next adjacent sail unit 102, which will be the P2 sail unit 102 in this example embodiment. In this example embodiment, spacing distance 150 between the P1 and P2 sail units 102 is 16.5 m, and so the next double ring marker along white rope 130 is provided at a spacing distance 150 of 16.5 m from the first double ring marker. The P1 sail unit 102 is thus drawn along starboard side 118 by a distance of 16.5 m, so that the P2 sail unit 102 can be secured to white rope 130 at the desired spacing distance 150 from the P1 sail unit 102.
This process is repeated until all of the port side sail units (P1 through P9 in this example embodiment) are coupled to white rope 130 at the desired spacing distance 150 from one another on the starboard side.
The port side sail units are then drawn around the stern 122 of the ship 101 with their sails in a movement configuration (i.e. with upper and lower booms 106, 104 oriented generally parallel to the side of ship 101) until the first sail unit reaches the P1 position using rope system 126 actuated by capstan 134. Each one of the sail units 102 P1 through P9 are then lowered into position and secured in place on their respective mounting points 200 as described below. In the illustrated embodiment, each one of sail units 102 P1 through P9 are released from white rope 130 by removing the free end 146 of webbing loop 142 from horncleat 148 and removing the securing end 144 of webbing loop 142 from white rope 130.
At this stage, and in this example embodiment, the lower and upper booms 104, 106 of the port side sail units 102 can be turned through 90° so that square sails 108 will be oriented perpendicular to the port side 120 of ship 101, which is the initial configuration in which sail units 102 would be deployed for use.
After the port side sail units 102 have been released (P1 through P9 in this example embodiment), the continuous rope 128/130 is drawn around ship 101 using capstan 134 until the a double ring marker on white rope 130 is again adjacent the loading position for sail units 102, i.e. at the S3 position in this example embodiment.
The first starboard sail unit 102 that will occupy the S1 position (i.e. the position on the starboard side 118 closest to bow 124) is then loaded at the loading position (i.e. the S3 position in this example embodiment) and lashed to white rope 130 at the first double ring marker. Because the S1 sail unit 102 does not need to navigate the corners at the stern 122 of ship 101, in some embodiments a shorter simple webbing loop 142 can be used for loading the starboard side sail units than was used for loading the port side sail units, which did have to navigate the stern 122 of ship 101.
Once the S1 sail unit 102 has been lashed to white rope 130, capstan 134 is actuated to draw the S1 sail unit towards bow 124 by the predetermined spacing distance 150 (i.e. 16.5 m in this example embodiment). Once the second double ring marker reaches the loading position (i.e. the S3 position in this example embodiment), the sail unit 102 that will occupy the S2 position is loaded and lashed to white rope 130 at the second double ring marker, and both the S1 and S2 sail units 102 are drawn towards bow 124 in the movement configuration until the S1 sail unit reaches the S1 position. Both the S1 and S2 sail units 102 are then lowered onto rails 112, and are deployed and locked into position on their respective mounting points 200 as described below, and the S1 and S2 sail units are unlashed from white rope 130 by removing webbing loops 142.
At this stage, and in this example embodiment, the lower and upper booms 104, 106 of the S1 and S2 sail units 102 can be turned through 90° so that square sails 108 will be oriented perpendicular to the starboards side 118 of ship 101, which is the initial configuration in which sail units 102 would be deployed for use.
Capstan 134 is then actuated to return the first double ring marker to the loading position (i.e. the S3 position in this example embodiment). Each of the remaining S9 through S3 sail units 102 is then loaded and lashed to white rope 130 at the appropriate spacing distance 150 and drawn towards the stern 122 of ship 101 in the movement configuration until all of the S3 through S9 sail units are in position. The S3 through S9 sail units 102 are then lowered, locked and released and their upper and lower booms 104, 106 can be turned through 90° so that square sails 108 will be oriented perpendicular to the starboards side 118 of ship 101, which is the initial configuration in which sail units 102 would be deployed for use.
In embodiments in which an auxiliary bow-mounted sail unit 103 is used, auxiliary bow-mounted sail unit 103 is mounted at the bow at any desired time during the loading sequence of sail units 102, e.g. before, after or during the loading of sail units 102 onto rail system 112. In one example embodiment, the auxiliary bow-mounted sail unit 103 is mounted on a bow cradle provided at the bow 124 of ship 121 after the first sail unit 102 (e.g. the P1 sail unit 102 in this described example embodiment) has been mounted on rail system 112 and cinched to white rope 130.
An example embodiment of a method for clearing some or all of the sail units 102, for example in preparation for engaging in dockside operations such as loading or unloading ship 101, is now described. This example embodiment is described with reference to clearing sail units 102 from the starboard side 118 of ship 101, but with appropriate modifications could be used to clear sail units 102 from the port side 120.
As a first step, the upper and lower booms 106, 104 of the starboard side sail units are rotated from their deployed configuration, i.e. an orientation in which the upper and lower booms 106, 104 extend generally perpendicularly to the side of the ship 101, as shown in
In some embodiments, yellow rope 132 is provided with double ring markers 152 (shown schematically in
The yellow rope 132 is removed from its spool 138 and is extended over the port side of the ship with its slack end looped over a horncleat provided at a suitable location, e.g. on the assembly containing capstan 134. Yellow rope 132 is then drawn down the port side 120 of ship 101 to its starting position, which in this example embodiment is with its third from last double ring marker 152 positioned adjacent the P9 sail unit 102. In this configuration, the final double ring marker 152 on yellow rope 132 is available for the S8 sail unit 102, and the second to last double ring marker 152 on yellow rope 132 is available for the S9 sail unit 102 when the starboard sail units 102 are drawn round to their deck-cleared configuration.
Once yellow rope 132 is secured in its desired starting position, the slack in yellow rope 132 is taken up and yellow rope 132 is wound round capstan 134. The P9 sail unit 102 is lashed to the yellow rope 132 at the third from last double ring marker 152 using a webbing loop 142 as described previously for white rope 130. The P9 sail unit 102 is drawn along the rail system 112 until the next stowage spacing interval 154 (i.e. 6 m in this example embodiment) double ring marker 152 on yellow rope 132 is adjacent the P8 sail unit 102. The P8 sail unit 102 is then lashed to yellow rope 132 using a webbing loop 142, and both the P8 and P9 sail units 102 are drawn along rail system 112 until the next stowage spacing interval 154 (i.e. 6m in this example embodiment) double ring marker 152 on yellow rope 132 is adjacent the P7 sail unit 102.
This process is repeated until all of the port-side sail units P9 through P2 have been gathered with the desired stowage spacing interval 154 (in this illustrated embodiment, 6 m) between them. The P1 port side sail unit 102 remains at the P1 position and braced, with the final double ring marker 152 (in this case indicating the 6 m stowage spacing interval 154) aligned with the horn cleat 148 of the P1 sail unit 102.
The free looped end 132A of yellow rope 132 is looped over a permanent horn cleat provided along the ship's handrail, and the opposite end of yellow rope 132 is released from capstan 134 and tied off the horn cleat 148 of the P1 sail unit 102, with slack spooled on the deck of the ship. The continuous rope formed from interconnected black rope 128 and white rope 130 is deployed about the perimeter of ship 101 as described previously, and the rope is passed through a rope guide 156 provided on the horn cleat 148 of the P1 sail unit 102, as shown in
White rope 130 (forming part of the continuous black and white rope 128, 130) is aligned so that its double ring markers 152 are positioned adjacent each starboard sail unit 102. The starboard sail units 102 are each lashed to white rope 130 using webbing loop 142 as described previously. Because the starboard sail units must pass around stern 122 of ship 101, the webbing loops 142 used to lash each starboard sail unit to white rope 130 should be sufficiently long to provide sufficient play to allow the sail units 102 to pass round the corners of stern 122.
Once the starboard sail units 102 are lashed to white rope 130, capstan 134 is used to pull the continuous black and white rope 128, 130 to move the starboard sail units around the stern 122 of ship 101 with their sails in the movement configuration until the sail unit 102 from the S9 position is close to the sail unit 102 from the port side P9 position(e.g. within about 10 m in one example embodiment), as shown in
The upper and lower booms 106, 104 on the S9 sail unit 102 are rotated through 90° so that they are in their storage configuration, i.e. so that they extend generally perpendicular to the side of ship 101, as shown for the port-side sail units 102 in
To move the sail units 102 back to their deployed configuration for use, the reverse process is followed.
The process of using rope system 126 to move sail units 102 about ship 101 is illustrated schematically in
This process is repeated until all of the port-side sail units have been drawn forward and secured in place on yellow rope 132, spaced apart by the stowage spacing interval, which can be but need not be the same distance between each pair of adjacent sail units 102. The sternmost end of yellow rope 132 is secured in any suitable manner, e.g. on a horncleat on the rail of ship 101, while the opposite (i.e. bow) end of yellow rope 132 is then removed from capstan 134 and secured in place to secure the port-side sail units in place, while black and white ropes 128, 130 are deployed about the perimeter of the ship and lashed together to make a continuous rope as described above.
The starboard-side sail units in the S1, S2, S3 and S4 positions are all lashed to white rope 130 at the double ring markers 152 indicating the spacing distance, with the sails 108 in their movement configuration (i.e. oriented parallel to the sides of ship 101), as shown schematically in
The S4 sail unit can then be lashed to yellow rope 132 if desired, and the S3 sail unit moved to a stowage distance from the S4 sail unit in a similar manner if desired, as shown in
In alternative embodiments, an alternative rope system having only two ropes 128 and 130 can be used to move sail units 102 about the perimeter of ship 101. For example, as illustrated schematically in
As shown in
Capstan 134 is then actuated to move the sail units around the side of the ship 101, and each successive sail unit is moved to the storage configuration (i.e. with upper and lower booms 106, 104 extending perpendicular to the side of ship 101) and secured in position along the rail of ship 101 until the starboard side of ship 101 has been cleared of sail units, as shown in
Any suitable rail system along which sail units 102 can be moved can be used in various embodiments. With reference to
Sail units 102 each provide a sail 108 and mast 110 mounted on a base unit 204. Base unit 204 includes all controls and motors required for its operation in some embodiments. Sail units 102 are mounted in an array on rail system 112 at suitable locations about ship 101. In some embodiments, base unit 204 has a housing 205 for containing mast 110 that is generally cylindrical.
In the illustrated embodiment, rail system 112 has a top rail 114 and a bottom rail 116. As shown in
As shown in
The base portion of top rail 114 is provided with a plurality of apertures 220 to allow water to run off of the ship's deck. The top and side faces formed by external top rail 212 and face rail 218 are generally flat surfaces save for the presence of occasional slots which receive the locating/fixing and locking pegs on each base unit 204 as described below. In some embodiments, the internal portion of top rail 114 includes an interior space 202, which can receive e.g. power and data cables used to operate rail-mounted auxiliary sail system 100.
Mounting points 200 are provided at each point along the perimeter of ship 101 at which it is desired to deploy sail units 102. With reference to
As can be seen in
As shown in
Sail units 102 can be loaded onto rail system 112 in any suitable manner and at any suitable location. In one example embodiment, with reference to
Sail unit 102 is brought to spacers 232 and the top plate 236 on the base unit 204 engages guides on the spacers 232. The crane then lowers sail unit 102, pivoting it until top plate 236 is flush with the spacer recess and setting the unit at a slight angle to the vertical (1.3° in the illustrated embodiment, although the exact angle is not critical and will be a consequence of the positioning of top rail 114 and bottom rail 116 in any given embodiment). Roller ball 210 is brought into contact with top rail 114 to engage top rail 114 as described above.
The loading operator can then open the fore and aft scissor jacks 238 provided on sail unit 102 somewhat, e.g. halfway in the illustrated embodiment, to lower the bottom wheels 208 into grooves 206 in bottom rail 116.
With roller ball 210 on the channel 216 in top rail 114 and bottom wheels 208 in groove 206 on bottom rail 116, sail unit 102 is self-supporting and the crane is released. Scissor jacks 238 can be opened to full with the wheels 208 and roller ball 210 supporting the unit. The aft spacer 232 is removed. With the unit in the high position, sail unit 102 can be rolled along rail system 114 out of the way and/or to the required position about ship 101, e.g. using rope system 126 as described above. With sail unit 102 out of the way, aft spacer 232 can be put back into position and the next sail unit 102 loaded by crane.
As shown in
In the illustrated embodiment, lower and upper booms 104, 106 (and therefore sails 108) are offset horizontally along mast 110, i.e. mast 110 is not at a horizontal centrepoint of lower and upper booms 106, but rather is at approximately a ⅖:⅗ offset, i.e. positioned at approximately ⅖ of the width of booms 104, 106 as measured from a first edge, with the shorter portion of lower and upper booms 104, 106 being oriented inwardly towards the centre of ship 101 when sail units 102 are in use.
In the illustrated embodiment, sails 108 are roller blinds, with the sails 108 trapped within the upper and lower booms 106, 104 by rods 300 and 315, as shown in
Lower boom 104 is rotatable about its longitudinal axis, so that the cloth from which sail 108 is made can be wound around lower boom 104 as sail 108 is reefed or lowered. Correspondingly, as upper boom 106 is raised, lower boom 104 is rotated as sail 108 unfurls and is raised.
In the illustrated embodiment, to facilitate rotation of lower boom 104, a bottom boom insert 314 is provided (
To wind sail 108 about lower boom 104 as sail 108 is lowered and unwind sail 108 as sail 108 is raised, rods 300 and bottom boom insert 314 are coupled together via a set of pulleys 301 and reefing cables 303 as shown schematically in
As upper boom 106 is actuated upwardly by top boom collar 310 being raised, force is exerted on sail 108, causing lower boom 104 to rotate to allow sail 108 to be released and hoisted. Correspondingly, slack is introduced into reefing cable 303 by the upward movement of top boom collar 310, which is wound around bobbin 318 as bobbin 318 rotates. In the illustrated embodiment, bobbin 318 has a tapered surface 320, i.e. a taper from a radially inward point to a radially outward point.
When upper boom 106 is lowered, top boom collar 310 is lowered, e.g. by releasing hoisting cable 428 as described below. The lowering of top boom collar 310 pulls on reefing cable 303 at the point where reefing cable 303 reaches bobbin 318, thereby rotating bottom boom insert 314 and thus lower boom 404 as reefing cable 303 becomes unwound. Sail 108 is held fixed in position on lower boom 104 to rod 315, so that the unwinding of reefing cable 303 thus winds sail 108 back around lower boom 104. As the amount of sail 108 that is wound around lower boom 104 increases, the combined thickness of lower boom 104 and sail 108 will increase. In some embodiments, providing tapered surface 320 ensures that the apparent thickness of reefing cable 303 wound around bobbin 318 remains similar to the combined thickness of lower boom 104 and sail 108 throughout the raising and lower process, so that lower boom 104 and bottom boom insert 314 can rotate uniformly and smoothly together.
Each mast is capped by a mast head 302 with various fixing points and pulleys. The mast head 302 secures the various support cables that secure the mast against the rest of the structure of sail unit 102, and that secure and actuate lower and upper booms 104, 106, and sail 108. The mast head 302 also allows the control cables to extend towards the deck of the ship.
In the illustrated embodiment, mast head 302 holds the mast strengthener arm 304 and the forward spur arm 306 integrally formed as a single-shaped beam, as shown in
Lower boom 104 is likewise held in position on mast 110 in any suitable manner, e.g. via bottom boom support cables 312. Lower boom 104 is secured against movement in the lateral direction in any suitable manner via aft and forward bottom boom support cables, such as aft boom support cables 312. Two sets of bottom boom support cables, forward and aft, are used in the illustrated embodiment to hold lower boom 104 in position so it does not flip over. In some embodiments, a bottom boom spur is provided that extends perpendicularly to lower boom 104 to extend bottom boom support cables forwards and away from sail 108 to prevent sail 108 from contacting or rubbing against the bottom boom support cables.
Operational parameters such as the reefing and the angle of mast 110 can be controlled in any suitable manner. In some embodiments, the reefing and the angle of mast 110 are controlled using cables, cogs and worm screws. The cables, cogs and worm screws can be controlled centrally electronically (e.g. centrally from the bridge of ship 101), by an operator at a control unit of mast 110 electronically, and/or by an operator at a control unit of mast 110 in a manual fashion.
In one embodiment, automatic mechanical safety devices for conducting automated reefing of sail 108 are provided. In one embodiment, automatic mechanical safety devices for conducting automated mast release of mast 110 are provided. In some embodiments, these automatic mechanical safety devices can prevent or limit damage to ship 101, mast 110 or sail 108 through excessive wind and/or sudden gusts of wind.
In one embodiment, the automatic mechanical safety device provides an auto-reefing function for sails 108 and is referred to generally as automatic reefing sail safety feature 400. The auto-reefing function is triggered by a top boom flex detecting cable 402, shown schematically in
The position of top boom flex detecting cable 402 is illustrated schematically in
Top boom flex detecting cable 402 acts via appropriately positioned pulleys, cogs and lever on a variable lever 408 (
With reference to
Under normal operating conditions experienced when raising or lowering sail 108, inertia drum 414 acts as a damping member and is able to absorb typical forces applied by top boom flex detecting cable 402, i.e. inertia drum 414 does not rotate particularly rapidly, and the turning of the teeth of rotating actuator cog 416 correspondingly turns only a few teeth on rotating lever cog 418. Actuating lever 409 and variable lever 408 are thus rotated only by small amounts that are insufficient to release drum latch 410, which is ordinarily biased inwardly against an outer circumference of top boom cable drum 422 as described below.
However, upon the occurrence of a strong wind event, e.g. a strong gust of wind or a sustained wind above a certain speed, inertia drum 414 is not able to absorb the rotating forces applied by flex detecting cable 402, with the result that rotating actuator cog 416 rotates rotating lever cog 418 to a sufficient extent to lift actuating lever 409 to a sufficient extent to allow variable lever 408 to actuate drum latch 410, e.g. as shown in
In the illustrated embodiment, an actuating cable 413 is movable by the lifting of actuating lever 409 to the activated position, and actuating cable 413 is positioned to exert an upward force on first end 408A of variable lever 408. This causes variable lever 408 to pivot about a pivot point 415, so that second end 408B of variable lever 408 is displaced downwardly, to exert a downward force on drum latch 410 via a second actuating cable 417.
Actuation of drum latch 410 releases the top boom cable drum 422 for rotation because drum latch 410 is ordinarily inwardly biased to remain engaged with a securing recess 424 provided along the outer circumference 426 of a portion of top boom cable drum 422. Drum latch 410 can be inwardly biased to remain engaged with securing recess 424 in any suitable manner, for example via a spring biasing drum latch 410 inwardly in a manner similar to a door latch.
When actuated by variable lever 408, drum latch 410 is pulled outwardly out of securing recess 424 (best seen in
In some embodiments, hoisting cable 428 is run as a closed loop running around the top boom cable drum 422 and up to the top of upper boom 106 at one end, and up to the bottom of upper boom 106 at the opposite end.
Once the pressure applied by top boom flex detecting cable 402 has subsided, inertia drum 414 again is able to damp small forces and variable lever 408 does not actuate drum latch 410. Drum latch 410 thus returns to its inwardly biased securing configuration, and is biased radially inwardly along the outer circumference 426 of top boom cable drum 422. Thus, once top boom cable drum 422 completes one rotation, drum latch 410 becomes aligned again with securing recess 424 and extends inwardly inside securing recess 424, to again secure top boom cable drum 422 in place and prevent top boom 106 from dropping further, unless a significant wind event again actuates variable lever 408.
As noted, rotation of top boom cable drum 422 as described above releases hoisting cable 428 to allow top boom 106 to move downwardly. In some embodiments, the circumference of top boom cable drum 422 about which hoisting cable 428 is wound corresponds to approximately 1/10th the vertical height of mast 110. Thus, activation of variable lever 408 and corresponding rotation of top boom cable drum 422 by one rotation will result in a 1/10th drop in height of top boom 106, or approximately a 10% decrease in the surface area of sail 108 exposed to the wind.
In some embodiments, the process of reefing sail 108 using automatic sail safety reefing feature 400 may be repeated one, two, three or more times until an appropriate degree of reefing of sail 108 has been reached.
As best seen in
As also seen in
In alternative embodiments, rather than using a hoisting cable 428 wound round top boom cable drum 422, a continuous chain can instead be run up and down mast 110, connected to raise and lower upper boom 106, and wound round a chain-grabbing drum (i.e. a drum with fingers or projections that can be inserted into the links of the chain to wind the chain upwardly to raise upper boom 106 or downwardly to allow upper boom 106 to be lowered) and the chain-grabbing drum could take the place of top boom cable drum 422 in the described embodiment. Such an embodiment might provide more reliable operation over a long period of time, as a chain may be less prone to stretching than a cable. In such embodiment, the chain-grabbing drum could be rotated in the same manner as described above for rotating top boom cable drum 422 to allow upper boom 106 to be raised and lowered, including by the operation of automatic reefing safety sail feature 400.
In one embodiment, the automatic mechanical safety device provides an automatic rotational release of mast 110 that allows sail 108 to rotate to be aligned with the wind, to very rapidly release the wind pressure on sail 108, referred to generally as automatic mast rotation release feature 500. In this embodiment, a mast strengthener cable 502 is coupled to mast 110 (e.g. as shown in
In the illustrated embodiment, chain tensioners and a spring are used to trigger a mechanical switch to automatically release mast 110 after a predetermined amount of force has been exerted on mast 110. As shown in
In more detail, projecting tab 508 sits with a first end 508A fixed within retainer 510 and that is biased at its first end by spring 512 contained within retainer 510 via eye bar 511. Retainer 510 acts like a chain tensioner, and is engaged with mast strengthener cable 502 and a fixed point on ship 101 so that forces exerted by mast strengthener cable 502 during normal sailing operations are ordinarily absorbed by spring 512.
Upon the occurrence of a strong wind event that causes mast 110 to flex beyond an acceptable predetermined limit and thereby exert a predetermined amount of force on mast strengthener cable 502, the force exerted by mast strengthener cable 502 on retainer 510 compresses spring 512 to a sufficient extent that a sprung locking tab 514 pivotably mounted within retainer 510 fully enters retainer 510. Locking tab 514 enters retainer 510 and engages with the first end 508A of projecting tab 508 as shown in
Locking tab 514 thus becomes locked in place. As this occurs, the second end 508B of projecting tab 508 moves downwardly so that mechanical switch 503 is forced downwardly and actuated. Actuation of switch 503 pulls pin 518 out far enough for the mast releasing weight 520 to drop (
The spring 512 is selected based on the application of Hooke's law so that once the predetermined amount of force has been exceeded, the spring will experience a corresponding predetermined linear displacement. In some embodiments, the properties of spring 512 and retainer 510 acting as a cable tensioner are selected to ensure that the automatic mast rotation release feature 500 is working within a desirable range of operating margins.
The actuation of mechanical switch 503 pulls pin 518 to release mast release weight 520, which by falling lifts mast cog 504 off of worm screw 506 via cable 522 and pulley 524, as shown by the raised position of mast cog 504 illustrated in
Once mast cog 504 is free of worm screw 506 (which is ordinarily used to rotate mast 110), mast 110 is free to rotate, and because sail 108 is offset, one side of sail 108 will experience a greater wind force than the other side of sail 108, thereby forcing sail 108 to turn parallel to the wind, rapidly decreasing the wind forces applied to sail 108 and mast 110, as shown by the differences in the position of sail 108 in the ordinary operating configuration shown in
In some embodiments, including the illustrated embodiment, automatic mast rotation release feature 500 is configured to automatically trigger automatic reefing sail safety feature 400 to fully reef sails 108 if automatic mast rotation release feature 500 is triggered. As best seen in
In some embodiments, appropriate shielding and weatherproofing can be provided to prevent components of sail units 102 (e.g. cables and levers on the control panel) from becoming damaged due to exposure to ocean weather conditions.
The function of auxiliary sail system 100 when used as described above is to assist the engines of ship 101 and save fuel. Thus, the margin of the operation of sail system 100 is well within the limits of mast failure or ship capsize, which may lower the lead time from the beginning of development through testing to sales.
Sail units 102 can also be adjusted in any suitable manner to allow ship 101 to be used as any normal ship. For example,
Maintenance of various parts of sail system 100 can be done while ship 101 is en route. Because sail system 100 is only an auxiliary sail system, it is not critical to the progress of ship 101, which means that repairs can be scheduled for calm weather or port, and need not be completed immediately. Ship 101 can still continue its journey, potentially more slowly, if some or all sail units 102 fail.
Suitable materials for making the various components of auxiliary sail system 100 can be selected by those skilled in the art. For example, in some embodiments, mast 110 and lower and upper booms 104, 106 may be made of aluminum. In such embodiments, to avoid aluminum/steel chemical reactions, resin barriers can be used. In alternative embodiments to avoid aluminum/steel chemical reactions, a design of sail system 100 that uses all steel e.g. for mast 110 and lower and upper booms 104, 106, could be used. In some such embodiments, the mast and booms would be triangular open frames such as those used in cranes and broadcast pylons. In alternative embodiments and as a more sustainable material, in some embodiments mast 110 and/or lower and upper booms 104, 106 could be made from timber, for example laminated sitka spruce, which could be produced to effective lengths.
The construction and connection of the various components of auxiliary sail system 100 would be within the expected knowledge of the person of ordinary skill in the art. In one example embodiment, cable fixing points are made by chain link traps using a primary locking plate, a secondary locking plate, and an ‘R’ clip to secure to their points of use, which allows rigging/de-rigging to be done manually by as few as two persons, without tools. However, any suitable engagement mechanism can be used in alternative embodiments.
While an example embodiment of a rail-mounted auxiliary sail system 100 has been described in conjunction with the example embodiments of automatic mechanical safety devices described herein, in alternative embodiments, other mounting systems could be used to affix appropriate sail units to a ship. For example, in some embodiments, the masts can be mounted at fixed points, and a derigging system can be provided to move the sail unit out of the way, for example to permit loading and unloading of cargo in port. In some embodiments, the masts can be mounted on and movable with respect to a rail system, and a motor can be provided to move each sail unit along the rail system.
In still a further alternative embodiment, a ‘curtain rail’ mounting system can be used, and a fixed cable can extend around the ship and be used to move the sail units along the rail system. In some such embodiments, the fixed cable can be moved using a motorised capstan, and the sail units can be lashed to the fixed cable in any suitable manner so that movement of the cable will draw the sail units along the rail system.
In still a further embodiment, a ‘pocket’ mounting system can be used to secure some of the sail units 102, in which the mast is secured within a pocket that is in turn secured to the side of the ship.
While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are consistent with the broadest interpretation of the specification as a whole.
This application claims priority to and is a continuation-in-part of U.S. patent application Ser. No. 15/784,148 filed 15 Oct. 2017, and claims priority to and the benefit of U.S. provisional patent application No. 62/408,733 filed 15 Oct. 2016. Both of the foregoing applications are incorporated by reference herein in their entireties.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CA2017/051519 | 12/14/2017 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62408733 | Oct 2016 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15784148 | Oct 2017 | US |
| Child | 16341878 | US |
