Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
  • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
  • B63H5/125—Arrangements on vessels of propulsion elements directly acting on water of propellers movably mounted with respect to hull, e.g. adjustable in direction, e.g. podded azimuthing thrusters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
  • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
  • B63H5/14—Arrangements on vessels of propulsion elements directly acting on water of propellers characterised by being mounted in non-rotating ducts or rings, e.g. adjustable for steering purpose
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H1/00—Propulsive elements directly acting on water
  • B63H1/02—Propulsive elements directly acting on water of rotary type
  • B63H1/12—Propulsive elements directly acting on water of rotary type with rotation axis substantially in propulsive direction
  • B63H1/14—Propellers
  • B63H1/16—Propellers having a shrouding ring attached to blades
  • B63H2001/165—Hubless propellers, e.g. peripherally driven shrouds with blades projecting from the shrouds' inside surfaces

Definitions

• the present invention relates to a propulsion unit for being mounted on a submerged portion of the hull of a waterborne vessel, the propulsion unit comprising a propeller nozzle for being pivotally mounted to the hull, a propeller rotatably arranged inside the nozzle, a drive means for driving the propeller, and a deployment mechanism for controlling the orientation of the propeller nozzle.
• the present invention further a vessel comprising such propulsion unit.
• a propulsion unit for being mounted on a submerged portion of the hull of a waterborne vessel, the propulsion unit comprising a propeller nozzle for being pivotally mounted to the hull, a propeller rotatably arranged inside the nozzle, a drive means for driving the propeller, and a deployment mechanism for controlling the orientation of the propeller nozzle, wherein the propeller nozzle is pivotally around a nozzle pivoting axis intersecting the propeller nozzle, between a deployed orientation wherein the propeller is arranged in a substantially upright position suitable for providing thrust for moving the vessel and a retracted orientation wherein the propeller is arranged in a tilted or substantially horizontal position to reduce a draught of the vessel.
• an improved propulsion unit in particular a more efficient propulsion unit in which a relatively large propeller diameter may be utilized, while at the same time accommodating for low water depths.
• the propulsion unit is in particular suited for vessels operating in both deep as well as in shallow water. During normal operation, the propulsion unit is flipped down. This allows for much larger propeller diameter than for conventional propulsion unit.
• the propeller and propeller nozzle may be turned to reduce the draught of the vessel and due to the particulars of the invention the turning radius of the propeller and propeller nozzle becomes as little as possible, helping to reduce the spaced needed to accommodate the propulsion unit.
• the nozzle pivoting axis may extending in a direction perpendicular to a direction of an axis of rotation of the propeller. Also, the nozzle pivoting axis may extends in a direction substantially transversal to a direction of sailing of the waterborne vessel.
• the nozzle pivoting axis may be offset from the axis of rotation of the propeller.
• attachment points for the propeller nozzle may be arranged closer to the hull of the vessel compared to a propulsion unit wherein the pivoting axis is coincident with an axis of rotation of the propeller. Having attachment points closer to the hull results in a better transmission of forces between the propulsion unit the hull.
• the dimensions of the supporting structures may be reduced, which may improve the hydrodynamic characteristics of the hull and reduces drag.
• reducing the dimension of the supporting structure may reduce draught of the vessel when the propeller nozzle is in the retracted orientation.
• the offset rotating axis enables the use of larger propellers, which may be advantageous.
• the pivoting axis may intersect the axis of rotation of the propeller.
• the propeller may be rim-driven and in this embodiment the drive means may be a permanent magnet motor. The principles of a rim driven propeller utilizing permanent magnets have previously been disclosed
• stationary permanent magnets may be provided in the propeller nozzle and the propeller may be mounted in a propeller housing provided with permanent magnets and rotatably arranged inside the propeller nozzle.
• a bearing for the propeller housing is provided .
• an advantage of providing a rim-driven propeller is that the transmission for torque is optimized compared to traditional shaft mounted and centre driven propellers. The transmission of torque becomes even more important when large propellers are employed.
• the required power may be reduced by approximately 20%, while vessel's thrust is maintained . This provides great savings on space, material use, fuel consumption etc. Additionally, other advantages include reduced noise and vibration, and the ability to actively compensate for vessel undulations.
• the propeller nozzle may be adapted to be attached to supporting structures extend ing from the submerged portion of the hull .
• the propeller may be mounted on a rotatable propeller shaft supported by a supporting structure extending inside the propeller nozzle and the drive means may be a motor arranged to rotate the propeller shaft.
• the propulsion unit may be adapted to be pivotally mounted to the submerged portion of the hull about a substantial vertical azimuth axis thereby provid ing an azimuth thruster functionality.
• a direction of thrust from the propulsion unit may be directed in other directions than otherwise provided by the propeller, which may be used for enhanced steering of the vessel .
• the invention further relates to a waterborne vessel, such as an offshore supply vessel or an mobile offshore drilling unit, comprising one or more of the above described propulsion unit.
• a waterborne vessel such as an offshore supply vessel or an mobile offshore drilling unit, comprising one or more of the above described propulsion unit.
• Figure 1 shows two propulsion unit mounted on a vessel
• Figure 2a and 2b shows a vessel comprising a propulsion unit
• Figure 3a and 3b shows different orientations of a propulsion unit
• Figure 4a and 4b illustrates the relationship between a thrust axis and a pivoting axis of a propulsion unit according to one embodiment of the invention
• Figure 5a shows propulsion unit
• Figure 5b and 5c shows a cross section of the propulsion unit of Fig. 5a along line AA' and B, respectively.
• Fig. 1 shows two propulsions unit mounted on a submerged portion of a hull 2 in an aft section of a vessel 1.
• Each propulsion unit comprises a pivotally mounted propeller nozzle 13 and a rotatable propeller 14 arranged inside the nozzle.
• a deployment mechanism 15 is provided for pivoting the propeller nozzle and the propeller about a nozzle pivoting axis 17 between a deployed orientation and a retracted orientation.
• the propeller in the deployed orientation shown in Fig. 2a the propeller is arranged in a substantially upright position suitable for providing thrust for moving the vessel as and in the retracted orientation shown in Fig. 2b the propeller is arranged in a tilted or substantially horizontal position to reduce a draught D of the vessel.
• the propulsion unit further comprises drive means 16 for driving the propeller as will be further described below.
• the propulsion units 10 are shown to be mounted between a central supporting structure 30 and side supporting structures 31 extending from the hull 2.
• the propulsion unit may also be mounted to on a hull in a number of other ways without departing from the scope of the invention.
• Nozzle protrusions 131 extends from the propeller nozzle 13 and provide attachment points for attachment with the supporting structures.
• the propeller nozzle is mounted using the necessary bearings to provide the pivotal motion.
• the deployment mechanism 15 provided for moving the propeller nozzle is shown in further detail in Fig . 4b.
• the deployment mechanism shown comprises a pivoting arm 151 mounted on the nozzle protrusion 131 that in turn is connected to a linear actuator, such as a hydraulic cylinder 152.
• a linear actuator such as a hydraulic cylinder 152.
• a piston 153 of the hydraulic cylinder is moved forward or backwards, dependent on the operation of an associated hydraulic pump, the movement of the piston is transferred to the pivoting arm 151 that facilitates the movement of the propeller nozzle 13 and propeller 14.
• the propeller nozzle and the propeller is turned about the nozzle pivoting axis 17 that intersecting the propeller nozzle.
• the pivoting axis extends in a direction perpendicular to a direction of an axis of rotation 142 of the propeller.
• the direction of the axis of rotation of the propeller 142 which may also be denoted the thrust direction of the propeller, gradually shifts.
• the nozzle pivoting axis may also extends in a direction substantially transversal to a direction of sailing of the waterborne vessel.
• Figure 2a and 2b shows how movement of the propeller nozzle from the deployed orientation in Fig . 2a to the retracted orientation in Fig. 2b reduces the draught, D of a vessel comprising one or more propulsion units according to the invention.
• the lower most point of the propeller nozzle is decisive to the draught of the vessel, where as in Fig. 2b the previous lower most point of the propeller nozzle is now above the lover most point of the vessel and the draught, D is hereby reduced.
• Fig. 4a and 4b illustrates how the pivoting axis 17 may be offset from the axis of rotation 142 of the propeller by an offset-distance, r.
• the dimensioning moment of the present propulsion unit may be no more than 1/10.
• the offset-distance, r may be less than or equal to half the maximum diameter of said propeller.
• the offset-distance, r may be in the range of 0 to 1.5 meter.
• the support arrangement for the propulsion unit must be dimensioned with respect to the moment of the propeller nozzle and propeller about the pivoting axis and a small offset-distance, r ensures that the moment is correspondingly low. Further, as the pivoting axis 17 is located relatively close to the hull the forces required to pivot the propeller nozzle and propeller is relatively low compared to traditional retractable azimuth thrusters and by being attached to the hull at two points the propulsion unit provides a stiff and strong structure.
• the propeller may be rim-driven by a permanent magnet motor.
• the propulsion unit 10 is shown to comprise stationary permanent magnets 163 arranged along an inner circumference of the propeller nozzle and the propeller 14 is mounted in a propeller housing 161 rotatable arranged inside the propeller nozzle.
• An outer circumference of the propeller housing is provided with rotating permanent magnets 162, and together the stationary and the rotating permanent magnets provide a bearing for the propeller housing able to absorb both axial and radial loads.
• the propeller nozzle constitutes a stator 164 comprising windings for providing a rotating magnetic field adapted to rotate the propeller housing comprising permanent magnets thereby constituting a rotor.
• the propeller housing may be rotated and a permanent magnet motor for driving the propeller is provided.
• a structure for supporting a propeller shaft is provided inside the propeller nozzle.
• the propeller shaft is arranged in a centre of the nozzle and the supporting structure extends from the circumference of the propeller nozzle towards the centre to support the propeller shaft.
• the propeller shaft may be supported at several points along the propeller shaft.
• the propeller is mounted on the propeller shaft and the drive means is a motor arranged to rotate the propeller shaft.
• Figure 3a and 3b show how power lines 165 for supplying power to the drive means 16, such as a permanent magnet motor. The power lines are routed from the interior of the hull to the propulsion unit via attachment point of the propeller nozzle protrusions.
• propulsion units according to embodiments of the invention are shown to be arranged in the rear part of a vessel as a main source of propulsion. However, propulsion units according to the invention may also be used for providing thrust elsewhere, such as a bow thruster to reduce turning radius or ease berth by providing a transversal trust force.

Landscapes

• 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)
• Actuator (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=51390026

Family Applications (1)

Country Status (8)

Families Citing this family (3)

Citations (3)

Family Cites Families (10)

• 2014
  • 2014-08-22 DK DK14181977.1T patent/DK2987719T3/en active
  • 2014-08-22 ES ES14181977.1T patent/ES2627849T3/es active Active
  • 2014-08-22 EP EP14181977.1A patent/EP2987719B1/en active Active
• 2015
  • 2015-08-21 WO PCT/EP2015/069257 patent/WO2016026962A1/en active Application Filing
  • 2015-08-21 JP JP2017510497A patent/JP2017525613A/ja active Pending
  • 2015-08-21 CN CN201580045245.9A patent/CN106715260A/zh active Pending
  • 2015-08-21 KR KR1020177007863A patent/KR20170047302A/ko unknown
• 2016
  • 2016-08-23 HK HK16110058.0A patent/HK1221946A1/zh not_active IP Right Cessation

Patent Citations (3)

Also Published As

Similar Documents

Legal Events