This application claims priority to European Application No. 22161015.7, filed on Mar. 9, 2022, the disclosure and content of which is incorporated by reference herein in its entirety.
The present disclosure relates to a marine propulsion system mounted on opposite sides of the hull on a marine vessel and to a vessel comprising such a marine propulsion system.
Known marine vessels commonly comprise one or more propulsion units such as an outboard engine, a stern drive or a pod or azimuthing drive.
Outboard engines are attached to the transom and will as a rule take up most of the space at the stern portion of the hull. As the rearmost portion of the vessel will be taken up by the engines, the fitting of a stern swim platform or similar accessories will be difficult, if not impossible.
Stern drives and a pod drives can be driven by an internal combustion engine (ICE) arranged within the hull of the vessel. Torque is then transmitted from the ICE through the hull to the propulsion elements. Mounting a drive unit and the transmission for such drive units within the hull of the vessel can utilize a significant amount of space. In operation, heat from the drive unit may be removed using a cooling system which as a rule employs water drawn in from the ambient marine environment. This often involves drawing in saline water from the sea and pumping it through the coolant system, which can cause problems with corrosion. Further, vibration isolation and dampers may be installed to avoid undesirable vibrations from a vibration generated by rotary components in the drive unit being transmitted to the hull or other parts of the vessel. In the case of a stern drive, the transmission may pass through the transom of the vessel to reach the outer stern drive and the propellers. In the case of a pod drive, the transmission may pass through the lower part of the hull to reach the outer pod drive. In both cases this may utilize a suitable sealing arrangement between an opening in the transom or the hull and a rotary transmission shaft to prevent water from leaking into the hull.
All the above-mentioned drive units are also mounted either below near the waterline, which creates a problem not only for access during maintenance, but also for a simple visual inspection of the drives and their propellers.
The disclosure provides an improved marine propulsion system aiming to solve the above-mentioned problems.
An object of the disclosure is to provide a marine propulsion system for a marine vessel, which arrangement solves the above-mentioned problems.
The object is achieved by a marine propulsion system and a marine vessel comprising such a stern platform arrangement according to the appended claims.
In the subsequent text, the term “propulsor” is defined as a propulsion unit for propelling and maneuvering the vessel. The propulsors are preferably electrically driven but are not limited to this option. Alternatively, the propulsors can be driven by a source of hydraulic pressure. The propulsors are mounted on a pair of wings which have a hydrofoil shaped geometry. When the wings are in their operative positions the propulsors are mounted on submerged free ends of the respective wing. However, the wings do not function as conventional hydrofoils which are usually fixed and can lift the hull clear of the water at elevated speeds.
In the text, the term “central longitudinal axis” denotes an axis that extends through the centre of a hull, between the bow to the stern. Preferably, the centre of gravity of the vessel should coincides with the central longitudinal axis of the vessel, in order to avoid listing. For a single hull vessel, the central longitudinal axis of the vessel corresponds to the central longitudinal axis of the hull. For a multi-hull vessel, such as a catamaran or a trimaran, the vessel itself will have a central longitudinal axis. However, each individual hull will have its own central longitudinal axis, which will either coincide with or be parallel to the central longitudinal axis of the vessel. In the subsequent text, the central longitudinal axis will be used for both the vessel and for each hull, where applicable.
Further, the term “vertical axis” is used to denote the main extension of a first portion of each wing, from its attachment point and downwards along the hull. It should be noted that the wings are rotatable about a horizontal axis extending through the hull. Hence, the first portion of each wing extends substantially vertically downwards only when the wing is positioned in a neutral, non-angled datum position. The term “horizontal axis” is used to denote a transverse horizontal axis through the attachment points of the respective wing. The horizontal axis is orthogonal to the longitudinal central axis but does not necessarily intersect this axis.
According to a first aspect of the disclosure, the disclosure relates to a marine propulsion system comprising wings with a hydrofoil shaped geometry arranged for mounting on a longitudinal side section of a vessel comprising at least one hull. The wings are located adjacent the transom of the hull onto which they are mounted. The propulsion system comprises at least one pair of wings mounted equidistant from the central longitudinal axis of the vessel, measured in the transverse direction of the central longitudinal axis. Each wing comprises a first section extending downwards along the side section of the hull and at least partially below the waterline when the wing is in its operative position. In this position, the first section is mounted to the side section of the hull at or adjacent its upper end. Each wing further comprises a second section joined to a lower end of the first section. The second section extends at an obtuse angle away from the extension of the first section. The magnitude of this angle can be selected to substantially conform to the angle between the side of the vessel and the bottom of the hull adjacent the respective wing. Alternatively, the angle is selected so that the one or more propulsors mounted on the second section will clear the underside of the hull when the wing is in its operative position. The second section each wing is arranged to support at least one propulsor.
According to a first example, the propulsion system is mounted on the opposing outer longitudinal sides of a vessel comprising a single hull or twin hulls. Alternatively, the propulsion system is mounted on the opposing outer longitudinal sides of the central hull of a vessel comprising three hulls. In this example, each second section extends from the lower end of its corresponding first section of the respective wing and towards the central longitudinal axis of the hull on which the wing is mounted. In the above examples, the second sections of each pair of wing will extend towards each other.
According to a second example, the propulsion system is mounted on facing outer longitudinal sides of a vessel comprising twin hulls. In this example, each second section extends from the lower end of its corresponding first section of the respective wing and towards the central longitudinal axis of the hull on which the wing is mounted. In the above example, the second sections of each pair of wings will extend away from each other.
When the wings are located in their operative positions, the wings and their propulsion systems can be used for driving, steering and adjusting the attitude of the vessel. According to a first example, the first section of each wing is mounted rotatable about a vertical axis to facilitate turning of the vessel. When the first section is rotated an angle about its vertical axis by a suitable actuator, then the propulsors mounted on the second section will be rotated together with the first section. The thrust from the propulsors on each wing will then cause the vessel to turn or move in a desired direction.
For instance, when both wings are rotatable simultaneously in the same direction about their vertical axes, then the thrust from the propulsors will cause a turning movement of the vessel. In this example, the respective first sections can be rotated over the same, or substantially the same angle. This operation is primarily used when the vessel is travelling in a substantially forward or rearward direction.
Alternatively, each wing can be individually rotatable about its vertical axis. In this example, the respective first sections can be rotated in the same direction over dissimilar angles, or in opposite directions into freely selectable angles. This operation is primarily suited for low speed maneuvering in a marina and during docking and can be combined with a change in direction for the thrust from the propulsors. In this way the vessel can be driven forwards or backwards at a desired angle relative to the central longitudinal axis and even be displaced sideways during docking.
According to a second example, the first section of each wing can also or additionally be mounted rotatable about a common transverse horizontal axis substantially at right angles to the central longitudinal axis of the vessel. For instance, when both wings are simultaneously rotated an equal angle about the horizontal axis and in the same direction, then this facilitates trim of the at least one hull. For instance, if the wings are rotated so that the second sections are displaced to the rear of a position where the first sections are in a substantially vertical datum position, then the angled second sections cause a downward force that will lower the stern relative to the waterline. This position is suitable for trimming a vessel that is too heavy at the bow section, or for creating a wave suitable for wakeboarding. Similarly, if the wings are rotated so that the second sections are displaced to the front of the position where the first sections are in a substantially vertical datum position, then the angled second sections cause an upward force that will lower the bow relative to the waterline.
Alternatively, each wing can be individually rotated over unequal angles about the horizontal axis relative to vertical datum position, in order to facilitate counteraction of an undesired list of the at least one hull. Depending on the magnitude of correction needed for counteracting a list, one or both wings can be rotated.
In addition to the operative position described above, the wings can be displaced in at least one Inoperative position. According to a first example, each wing is rotatable from its operative position into a first inoperative position, where the first section extends rearwards relative to its operative position and where the second section and the at least one propulsor is arranged rearwards of the transom. This position is suitable for lifting the propulsors out of the water during mooring, in order to reduce the effects of marine growth and corrosion during periods of inactivity.
According to a second example, each wing is rotatable from its operative position into a second inoperative position, where the first section extends upwards relative to its operative position and where the second section and the at least one propulsor is arranged above the transom. This position is suitable for lifting the propulsors clear of the hull to a height and position wherein the propulsors and the wings are accessible for service. In this way, service and maintenance can be performed without having to remove any parts or the propulsion system from the vessel.
The marine propulsion system can comprise wings provided with at least one propulsor. The propulsors are preferably, but not necessarily, electric motors. According to a first example, the at least one propulsor comprises a conventional pushing thruster with one or more propellers at the trailing edge of the wing. According to a second example, the at least one propulsor comprises a pulling thruster with one or more propellers at the leading edge of the wing. According to a third example, the at least one propulsor comprises a combination of the above arrangements, with a pulling thruster at the leading edge of the wing and a pushing thruster at the trailing edge of the wing.
According to a second aspect of the disclosure, the disclosure relates to a marine vessel provided with a marine propulsion system as described in the above examples. As described above, the propulsion system comprises wings mounted on opposite sides of a vessel comprising at least one hull or mounted on facing sides of a vessel comprising two hulls.
The marine propulsion system according to the disclosure solves the problem of providing a stern drive or outdrive with electric propulsion without significant modifications of the hull or transom of a vessel. Further, the conventional interface for mounting a stern drive and its steering gear connections to a transom can be eliminated. Similarly, as a conventional inboard drive unit can be eliminated there is no need for an opening through the transom or for an associated sealing means for a drive shaft. In this way conventional drive units can be replaced by smaller and lighter electric motors and fuel tanks can be replaced by one or more battery packs which can be located in suitable positions for improved weight distribution.
A further advantage is that the pivotable wing arrangements with one or more propulsors can be used not only for propelling the vessel, but also for trim and for counteracting list. This eliminates the need for separate trim planes mounted to the hull below the waterline.
A further advantage is that the mounting of one or more propulsion units to a pivotable wing arrangement provides easy access to the propulsion unit for maintenance or for replacing parts thereof, such as a propeller. Pivoting the wings and the attached propulsion units to an angle of, for instance, 180° facilitates removal or maintenance of the propulsors, as the fastener means attaching the propulsors to the wings are freely accessible and can be removed safely when the entire unit is lifted out of the water to a position above the hull.
Further advantages and advantageous features of the disclosure are disclosed in the following description and in the dependent claims.
With reference to the appended drawings, below follows a more detailed description of embodiments of the disclosure cited as examples. In the drawings:
Each wing comprises a first section 107, 108 extending downwards along the side section 101 of the hull 115 and at least partially below the waterline when the wing is in its operative position. In this position, the first section 107, 108 is mounted to the side section 101 of the hull at or adjacent its upper end 107a (one shown). Each wing 103, 104 further comprises a second section 109, 110 joined to a lower end 107b (one shown) of the first section 107,108. The second section 109, 110 extends at an obtuse angle away from the main extension of the first section 107, 108. In this example, the second sections 109, 110 of each pair of wings 103, 104 will extend towards each other, but without coming into contact. The main extensions of the first sections 107,108 are indicated by the vertical axes Y1 and Y2, respectively, which axes pass through the respective attachment point 105, 106. The magnitude of this angle can be selected to substantially conform to the angle between the side of the vessel and the bottom of the hull adjacent the respective wing. Alternatively, the angle is selected so that the propulsors 111, 112, 113, 114 mounted on the second sections 109, 110 will clear the underside of the hull 115 when the wings 103, 104 are in their operative positions. The second section of each wing is arranged to support at least one propulsor. The embodiment in
When the wings 103, 104 are located in their operative positions, the wings 103, 104 and their propulsors 111, 112, 113, 114 can be used for driving, steering and adjusting the attitude of the vessel. According to a first example, the first section 107, 108 of each wing 103, 104 is mounted rotatable about the vertical axis Y1 and Y2, respectively, to facilitate turning of the vessel. According to a second example, the first section 107, 108 of each wing 103, 104 can also be mounted rotatable about a common transverse horizontal axis X axis at right angles to the central longitudinal axis of the vessel. The transverse horizontal axis X passes through the attachment points 105, 106 (one shown) of each upper end 107a (one shown) of the respective first section 107, 108. The rotation of the wings about the respective vertical axis Y1 and Y2 and/or the horizontal axis X is controllable by suitable electric or hydraulic actuators (not shown). The above-mentioned functions will be described in further detail below.
Each wing comprises a first section 207, 208 extending downwards along the side section 201 of the hull 215 and at least partially below the waterline when the wing is in its operative position. In this position, the first section 207, 208 is mounted to the side section 201 of the hull at or adjacent its upper end 207a (one shown). Each wing 203, 204 further comprises a second section 209, 210 joined to a lower end 207b (one shown) of the first section 207, 208. The second section 209, 210 extends at an obtuse angle away from the main extension of the first section 207, 208. The main extensions of the first sections 207,208 are indicated by the vertical axes Y1 and Y2, respectively, which axes pass through the respective attachment point 205, 206. The second section 209, 210 of each wing 203, 204 is arranged to support a pair of propulsors 211, 212, 213, 214.
In order to perform a turn, the first section 207, 208 of each wing 203, 204 is rotated in a desired direction about the vertical axes Y1 and Y2.
Each wing comprises a first section 307, 308 extending downwards along the side section 301 of the hull 315 and at least partially below the waterline when the wing is in its operative position. In this position, the first section 307, 308 is mounted to the side section 301 of the hull at or adjacent its upper end (not shown). Each wing 303, 304 further comprises a second section 309, 310 joined to a lower end (not shown) of the first section 307, 308. The second section 309, 310 extends at an obtuse angle away from the main extension of the first section 307, 308. The main extensions of the first sections 307, 308 are indicated by the vertical axes Y1 and Y2, respectively, which axes pass through the respective attachment point 305, 306. The second section 309, 310 of each wing 303, 304 is arranged to support a pair of propulsors 311, 312, 313, 314.
In order to perform a turn, the first section 307, 308 of each wing 303, 304 is rotated in a desired direction about the vertical axes Y1 and Y2.
Each wing comprises a first section 407, 408 extending downwards along the side section 401 of the hull 415 and at least partially below the waterline when the wing is in its operative position. In this position, the first section 407, 408 is mounted to the side section 401 of the hull at or adjacent its upper end 407a (one shown). Each wing 403, 404 further comprises a second section 409, 410 joined to a lower end 407b (one shown) of the first section 407, 408. The second section 409, 410 extends at an obtuse angle away from the main extension of the first section 407, 408. The main extensions of the first sections 407, 408 are indicated by the vertical axes Y1 and Y2, respectively, which axes pass through the respective attachment point 405, 406. The second section 409, 410 of each wing 403, 404 is arranged to support a pair of propulsors 411, 412, 413, 414.
In order to perform a docking maneuver, the first section 407, 408 of each wing 403, 404 is rotated in desired individual directions about the vertical axes Y1 and Y2.
Each wing comprises a first section 507, 508 extending downwards along the side section 501 of the hull 515 and at least partially below the waterline when the wing is in its operative position. In this position, the first section 507, 508 is mounted to the side section 501 of the hull at or adjacent its upper end 508a (one shown). Each wing 503, 504 further comprises a second section 509, 510 joined to a lower end 508b (one shown) of the first section 507, 508. The second section 509, 510 extends at an obtuse angle away from the main extension of the first section 507, 508. The main extensions of the first sections 507, 508 are indicated by the vertical axes Y1 and Y2, respectively, which axes pass through the respective attachment point 505, 506. The second section 509, 510 of each wing 503, 504 is arranged to support a pair of propulsors 511, 512, 513, 514.
When the wings 503, 504 are located in their operative positions, the wings 503, 504 and their propulsors 511, 512, 513, 514 can be used for adjusting undesired list of the vessel. As indicated above, the first section 507, 508 of each wing 503, 504 is mounted rotatable about the vertical axis Y1 and Y2, respectively, to facilitate turning of the vessel. In addition, the first section 507, 508 of each wing 503, 504 can also be mounted rotatable about a common transverse horizontal axis X axis at right angles to the central longitudinal axis Z of the vessel. The transverse horizontal axis X passes through the attachment points 505, 506 of each upper end 508a (one shown) of the respective first section 507, 508. In the example in
Each wing comprises a first section 607, 608 extending downwards along the side section 601 of the hull 615 and at least partially below the waterline when the wing is in its operative position. In this position, the first section 607, 608 is mounted to the side section 601 of the hull at or adjacent its upper end 608a (one shown). Each wing 603, 604 further comprises a second section 609, 610 joined to a lower end 608b (one shown) of the first section 607, 608. The second section 609, 610 extends at an obtuse angle away from the main extension of the first section 607, 608. The main extensions of the first sections 607, 608 are indicated by the vertical axes Y1 and Y2, respectively, which axes pass through the respective attachment point 605, 606. The second section 609, 610 of each wing 603, 604 is arranged to support a pair of propulsors 611, 612, 613, 614.
When the wings 603, 604 are located in their operative positions, the wings 603, 604 and their propulsors 611, 612, 613, 614 can be used for adjusting undesired list of the vessel. As indicated above, the first section 607, 608 of each wing 603, 604 is mounted rotatable about the vertical axis Y1 and Y2, respectively, to facilitate turning of the vessel. In addition, the first section 607, 608 of each wing 603, 604 can also be mounted rotatable about a common transverse horizontal axis X axis at right angles to the central longitudinal axis Z of the vessel. The transverse horizontal axis X passes through the attachment points 605, 606 of each upper end 608a (one shown) of the respective first section 607, 608. In the example in
In addition to the operative position described in
In addition to the operative position described in
Each wing comprises a first section 1107, 1108 extending downwards along each of the facing the side sections 1101a, 1101b of the respective hull 1115a, 1115b and at least partially below the waterline when the wing is in its operative position. In this position, the first sections 1107, 1108 are mounted to a respective side section 1101a, 1101b of each hull at or adjacent its upper end (see
In order to perform a turn, the first section 1107, 1108 of each wing 1103, 1104 is rotated in a desired direction about the vertical axes Y1 and Y2.
Each wing comprises a first section 1207, 1208 extending downwards along each of the facing the side sections 1201a, 1201b of the respective hull 1215a, 1215b and at least partially below the waterline when the wing is in its operative position. In this position, the first sections 1207, 1208 are mounted to a respective side section 1101a, 1101b of each hull at or adjacent its upper end (see
In order to perform a docking maneuver, the first section 1207, 1208 of each wing 1203, 1204 is rotated in desired individual directions about the vertical axes Y1 and Y2.
It is to be understood that the present disclosure is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.
Number | Date | Country | Kind |
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22161015.7 | Mar 2022 | EP | regional |