Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
  • B63H25/06—Steering by rudders
  • B63H25/38—Rudders
  • B63H25/382—Rudders movable otherwise than for steering purposes; Changing geometry
  • B63H25/383—Rudders movable otherwise than for steering purposes; Changing geometry with deflecting means able to reverse the water stream direction
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
  • B63H25/06—Steering by rudders
  • B63H25/38—Rudders
  • B63H25/381—Rudders with flaps
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
  • B63H25/44—Steering or slowing-down by extensible flaps or the like
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
  • B63H25/06—Steering by rudders
  • B63H2025/066—Arrangements of two or more rudders; Steering gear therefor

Definitions

• the present invention relates to a ship, comprising a propeller that is driveably connected to a drive, and a rudder system arranged downstream of the propeller and comprising at least one rudder configured to deflect a water flow induced by the propeller.
• the invention further relates to such a rudder system.
• Rudder systems are used to steer a ship, i.e. adjust the course of a moving ship.
• the rudders may be used to maintain a substantially straight course, or to steer and change the direction of movement of the ship.
• the driving direction of the propeller When a ship is moving in a forward direction and wants to decelerate, i.e. brake, the driving direction of the propeller may be reversed. In this way, the drive may cause a driving force that is directed in a driving direction opposite a direction of movement of the ship, thereby counteracting the actual movement of the ship and effectively decelerating the ship.
• a forward moving ship Once a forward moving ship has come to a standstill, and if the driving direction of the propeller is maintained in correspondence to a rearward directed driving force, the ship will start to accelerate and move in the rearward direction.
• a moving ship may be slowed down effectively to a standstill, and may successively be moved in an opposite direction.
• ships In order to reverse the driving direction of the propeller, ships need a reversing gear.
• a reversing gear adds to the complexity of the driving system. Furthermore, reversing the driving direction of the propeller takes precious time, which may not be available during an emergency brake. In general, the faster a ship is able to decelerate / brake, the safer the ship is.
• JP 2016037270 A discloses a ship wherein the driving direction of the propeller may be changed to slow down or reverse the movement direction of the ship, and thus applies to a ship having a reversing gear as described in the previous paragraph. JP 2016037270 A however also acknowledges that reversing the driving direction of the propeller takes precious time, and therefore proposes to apply a rudder system having two rudders that are arranged on opposite sides relative to a water flow induced by the propeller, said two rudders being pivotable symmetrically about the ship axis in opposite directions to each other to reduce the time for which the propeller is turning in inertia after stopping driving the propeller when a sudden stop is necessary, such as during an emergency brake, and to enable the propeller to start reversing quickly.
• DE 25 10256 Bl which is considered the closest prior art, discloses a ship, comprising a propeller that is driveably connected to a drive, and a rudder system arranged downstream of the propeller and comprising a pair of rudders arranged on opposite sides relative to a water flow induced by the propeller and configured to jointly deflect the water flow induced by the propeller.
• a ship comprising a propeller that is driveably connected to a drive, and a rudder system arranged downstream of the propeller and comprising a pair of rudders arranged on opposite sides relative to a water flow induced by the propeller and configured to jointly deflect the water flow induced by the propeller.
• JP H04358993 A, NL 7014527 and GB 422938 A which are acknowledged as further prior art, are all related to rudders that are to be applied as a single rudder of a ship, wherein said single rudder is positioned directly downstream of a propeller, i.e. centrally arranged in the water flow induced by said propeller.
• An objective of the present invention is to provide a ship comprising a rudder system, that is improved relative to the prior art and wherein at least one of the above stated problems is obviated or alleviated.
• a rudder system arranged downstream of the propeller and comprising a pair of rudders arranged on opposite sides relative to a water flow induced by the propeller and configured to jointly deflect the water flow induced by the propeller;
• each rudder of the pair of rudders comprises two flaps that are pivotable relative to each other between a forward sailing state and a reversing state;
• said flaps are oriented to define a scoop shape of the rudders to deflect and reverse the water flow.
• the orientation of these two flaps relative to each other is adjustable to thereby control a deflection of the water flow induced by the propeller.
• a high efficiency may be obtained.
• Conventional rudder systems such as described in the aforementioned prior art documents DE 25 10256 Bl, JP H04358993 A and NL 7014527, experience significant energy losses due to the different nature of these systems. After all, they fail to deflect the water flow in a gradual manner. Instead, they all block the flow stream induced by the propeller, thereby causing a pressure build up. The water will then start to flow to the direction of least resistance, i.e.
• the ship By orienting the flaps of the rudders to define a scoop shape, the water flow induced by the propeller may be deflected and reversed.
• the driving direction of the propeller may thus be unchanged, while the driving force is effectively reversed by said scoop shaped rudder.
• the ship is capable of effectively causing a forward deceleration or rearward propulsion of said ship, while there is no need for a conventional reversing gear.
• an even more important advantage is that the time required to reverse the driving force of the ship is significantly reduced. Consequently, the ship may decelerate / brake extremely fast, thereby improving safety and user comfort.
• a rudder system having a pair of rudders offers greatly improved maneuverability relative to rudder systems having a single rudder, because it may effectively direct substantially the whole water flow induced by the propeller. According to the present invention having rudders with two flaps, this improved maneuverability is obtained both in the forward sailing state and the reversing state.
• the rudder system is configured to deflect the water flow and steer the ship in the forward sailing state, and to deflect and reverse the water flow in the reversing state to cause a forward deceleration or rearward propulsion of said ship.
• At least one of the two flaps of each rudder, and even more preferably each of the two flaps of each rudder, comprises an asymmetrical cross section in top view to define a rudder shape that is configured to bend the water flow induced by the propeller in the reversing state.
• Such an asymmetrical shape may be defined by an outer side of at least one of the two flaps of each rudder, and even more preferably an outer side of each of the two flaps of each rudder, that is directed towards the propeller in the reversing state, comprising a non-straight shape.
• the outer side of the flap may comprise two or more straight sections that are connected via an obtuse angle, i.e.
• an outer side of at least one of the two flaps of each rudder, and even more preferably an outer side of each of the two flaps of each rudder, that is directed towards the propeller in the reversing state comprises a curvature that is configured to bend the water flow induced by the propeller.
• the orientation of these two flaps relative to each other is adjustable to thereby control a deflection of the water flow induced by the propeller.
• the curvature of the flaps allows the rudder system to provide an adjustable and substantially continuous curvature to thereby gradually deflect the water flow induced by the propeller. In this way, turbulence is prevented, and a high efficiency is obtained.
• the rudders of JP H04358993 A and NL 7014527 that are to be applied as a single rudder of the ship, each comprise two flaps having straight sides directed towards the propeller in the reversing state.
• an angle enclosed by the V-shape of the flaps may be adjusted, but the resulting V-shape will always cause a blocking and resulting turbulence, and will never be able to gradually deflect the water flow induced by the propeller.
• the curvatures of both flaps of each rudder are configured to form a continuous curve that is configured to gradually bend the water flow induced by the propeller.
• the continuous curve defines a smooth flow path, preventing turbulence to occur.
• the invention is further directed to a rudder system of or for a ship according to the invention.
• Figure 1 is a perspective view of a ship comprising a rudder system according to the invention, and a detailed perspective view of the rudder system being arranged in a straight forward sailing state;
• Figure 2 is a top view of the rudder system in the straight forward sailing state of
• Figure 1 Figure 3 is a top view of the rudder system in a forward sailing state while steering said ship;
• Figure 4 is a top view of the rudder system in a reversing state
• Figure 5 is a top view of the rudder system in a reversing state while steering said ship.
• the ship 1 comprises a hull 2 extending in a longitudinal direction 3.
• the ship 1 further comprises a propeller 4 that is driveably connected to a drive 5, and a rudder system 6 that is arranged downstream of the propeller 4.
• the rudder system 6 comprises a pair of rudders 7 arranged on opposite sides relative to a water flow 8 induced by the propeller 4 and configured to deflect the water flow 8 induced by the propeller 4.
• the water flow 8 may be directed by a nozzle 18.
• Each rudder 7 comprises two flaps 9, 10 that are pivotable relative to each other between a forward sailing state (as shown in Figures 2 and 3) and a reversing state (as shown in Figures 4 and 5).
• said flaps 9, 10 are oriented to define a scoop shape of the rudder 7 to deflect and reverse the water flow 8.
• the forward sailing state is related to forward propulsion of the ship 1, whereas the reversing state is active during forward deceleration, i.e. braking, and during rearward propulsion of said ship 1.
• the rudder system 6 is configured to deflect the water flow 8 and steer the ship 1 in the forward sailing state, and to deflect and reverse the water flow 8 in the reversing state to cause a forward deceleration or rearward propulsion of said ship 1.
• each rudder 7 is both pivotable relative to a common rudder shaft sleeve 11 that rotatably connects the rudder 7, and the two flaps 9, 10 thereof, to the ship 1.
• a rudder shaft sleeve 11 is a conventional way to arrange a conventional rudder, that has a single rudder shaft, to a ship 1 , and therefore the improved rudder system 6 according to the invention may also be arranged in retrofit.
• the rudder shaft sleeve may be a common rudder shaft sleeve 11 that comprises two concentrically arranged shafts 12, 13. These shafts 12, 13 are rotatably received in their common rudder shaft sleeve 11.
• Shaft 12 may be an outer shaft connected to flap 9 and shaft 13 may be an inner shaft connected to flap 10, or vice versa.
• the two flaps 9, 10 of each rudder 7 are pivotable independently from each other relative to their common rudder shaft sleeve 11.
• the common rudder shaft sleeve 11 comprises two concentrically arranged shafts 12, 13 as described above, they may rotate relative to each other inside said common rudder shaft sleeve 11 to define a shape of the rudder 7.
• the rudder 7 may be arranged in a scoop shape to deflect and reverse the water flow 8 that is induced by the propeller 4 ( Figure 4).
• the two flaps 9, 10 of each rudder 7 extend in substantially opposite directions relative to their common rudder shaft sleeve 11.
• the two flaps 9, 10 define a substantially straight shape of the rudder 7, reducing the drag thereof during normal forward sailing ( Figures 1 and 2).
• At least one of the two flaps 9, 10 of each rudder 7 may comprise an asymmetrical cross section in top view.
• each of the two flaps 9, 10 of each rudder 7 comprises an asymmetrical cross section in top view ( Figures 2-5).
• the asymmetrical cross section may be defined by a curved outer surface 14 on either one or both of a first side 15 and a second side 16 of the respective flap or flaps 9, 10. More in particular, the flaps 9, 10 may exhibit a wing-shaped profile.
• each rudder 7 may define a substantially continuously curved outer surface 14 that may guide the water flow 8 at a minimum drag and preventing unwanted turbulence.
• a continuously curved outer surface 14 as defined by the flaps 9 and 10 of a rudder 7 is best seen in the top views of Figures 4 and 5, that both relate to a reversing state.
• the water flow 8 induced by the propeller 4 is deflected and reversed to cause a forward deceleration / braking, or a rearward propulsion of said ship 1.
• Figure 4 shows a reversing state wherein the ship 1 will drive in a straight line
• Figure 5 shows a reversing state wherein the ship 1 will change direction.
• Figure 5 will steer the stern 17 of the ship 1 towards starboard side.
• the curved outer surfaces 14 of the two flaps 9, 10 of each rudder 7 may be rotated relative to the ship 1.
• These curved outer surfaces 14 that are arranged on the same side of the rudder 7 may be arranged on the first side 15, on the second side 16, or on both sides 15, 16.
• the first side 15 or the second side 16 may be directed inward or outward relative to the longitudinal direction 3 of the ship 1.
• the curved outer surfaces 14 on the first side 15 are directed inward, i.e. towards the water flow 8 induced by the propeller 4.
• the curved outer surfaces 14, 16 on the second side 16 are directed substantially forward relative to the ship 1.
• the ship 1 shown in the Figures comprises a rudder system 6 that comprises a pair of rudders, wherein each rudder 7 of the pair of rudders comprises two flaps 9, 10 that are pivotable relative to each other as described above.
• the pair of rudders is configured to jointly deflect the water flow 8 induced by the propeller 4 of the ship 1.
• the rudders 7 of the pair of rudders are arranged in a mirrored arrangement.
• the two rudders 7 are pivotable relative to each other and configured to rotate in the same direction relative to the ship 1 to deflect the water flow 8 and steer the ship 1 during forward propulsion thereof, and to rotate in an opposite direction relative to the ship 1 to deflect and reverse the water flow 8 during forward deceleration or rearward propulsion of said ship 1.
• the flaps 9, that are oriented forward in the forward sailing state of Figures 1 and 2, are directed towards each other in the reversing state of Figure 4.
• an extendable connector 19 such as a hydraulic cylinder 20, is connected between the outer shafts 12 of two rudders 7, which allow the connection to be made above water level. It is however conceivable that the extendable connector 19 is directly arranged between flaps 9 or flaps 10 of two rudders 7 of the pair of rudders. By adjustment of the length of the extendable connector 19, the flaps 9 or flaps 10 of two rudders 7 may be moved towards or away from each other.
• the rudders 7 of the pair of rudders are arranged on opposite sides relative to the water flow 8 induced by the propeller 4. More in particular, one rudder 7 of the pair of rudders is arranged on the port side relative to the water flow 8, and the other rudder 7 of the pair of rudders is arranged on the starboard side relative to the water flow 8.
• the flaps 9, 10 of the rudders 7 may be arranged substantially in line and adjacent the water flow 8 induced by the propeller 4 during straight forward propulsion of said ship 1. More in particular, the rudders 7 may be arranged just outside the water flow 8 during straight forward sailing, so that the water flow 8 is substantially guided between the two rudders 7 of the pair of rudders ( Figures 1 and 2).
• the rudders 7 may be rotated relative to their common rudder shaft sleeve 11, which houses the shafts 12, 30 of both flaps 9, 10 of the respective rudder 7.
• the water flow 8 is now deflected, and the ship 1 may be steered.
• the orientation of the rudders 7 shown in Figure 3 causes the ship 1 to steer towards starboard side.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• Ocean & Marine Engineering (AREA)
• Other Liquid Machine Or Engine Such As Wave Power Use (AREA)
• Toys (AREA)
• Braking Arrangements (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

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ID=69700247

Family Applications (1)

Country Status (3)

Citations (5)

• 2019
  • 2019-11-25 NL NL2024304A patent/NL2024304B1/en active
• 2020
  • 2020-11-19 WO PCT/NL2020/050730 patent/WO2021107773A1/en unknown
  • 2020-11-19 EP EP20815962.4A patent/EP4065463A1/en active Pending

Patent Citations (5)

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