The present invention relates to a stern platform arrangement mounted to a marine vessel.
Known marine vessels comprising a stern platform, such as a swim platform, are often provided with a propulsion unit in the form of a stern drive driven by an internal combustion engine (ICE) arranged within the hull of the vessel. Torque is then transmitted from the ICE to the stern drive via a transmission comprising shafts and gearing in order to drive a set of propellers on the stern drive.
Mounting a drive unit and the transmission required for such a drive unit within the hull of the vessel can require a significant amount of space. In operation, heat from the drive unit must 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, a vibration generated by rotary components in the drive unit and the transmission requires vibration isolation and dampers to be installed to avoid undesirable vibrations from being transmitted to the hull or other parts of the vessel. Finally, the transmission must pass through the transom of the vessel to reach the stern drive and the propellers. This requires a suitable sealing arrangement between an opening in the transom and a rotary transmission shaft to prevent water from leaking through the hull.
Further, when the vessel is provided with a stern swim platform it is often difficult to access a stern drive, as the swim platform can extend a fair distance aft of the transom. This creates a problem not only for access during maintenance, but also for a simple visual inspection of the stern drive and its propellers.
The invention provides an improved stern platform arrangement aiming to solve the above-mentioned problems.
An object of the invention is to provide a stern platform arrangement for a marine vessel, which arrangement solves the above-mentioned problems.
The object is achieved by a stern platform arrangement and a marine vessel comprising such a stern platform arrangement according to the appended claims.
In the subsequent text, the term “propulsion unit” is defined as an assembly comprising an outdrive having two sub-units. An upper unit contains drive units and a transmission and is enclosed in an upper drive housing. A lower unit contains a vertical driveshaft receiving power from the transmission in the upper unit and a gearbox providing power to a propeller shaft for driving at least one propeller. The component parts of the lower unit are enclosed in a gearbox housing. The upper and lower units are separated by a cavitation plate. A propulsion unit according to the invention differs from a conventional stern drive in that it does not comprise an inboard drive unit. The vessel is steered by pivoting the at least one propulsion unit or outdrive relative to the vessel, either by rotating the lower unit relative to the upper unit or by rotating the upper unit relative to a mounting attached to the vessel. The propulsion unit can be tilted up into a tilted position for trailer travel and between uses to avoid fouling.
According to a first aspect of the invention, the invention relates to a platform arrangement mounted to a stern portion of a marine vessel. The platform arrangement comprises at least one first platform section with a first transverse pivot joint mounted adjacent a transom and at least one propulsion unit mounted to a lower surface of the first platform section, wherein the at least one propulsion unit and the first platform section are tiltable between a drive position and an upwards tilted position.
The platform arrangement can further comprise a second platform section located in front of the at least one first platform section, which second platform section has a second transverse pivot joint mounted adjoining the first transverse pivot joint of a corresponding first platform section. The first and second platform sections are foldable relative to each other about their respective first and second pivot joints and are also individually foldable.
The at least one first platform section is arranged to extend rearwards from the first transverse pivot joint when the at least one propulsion unit is in its drive position. The first transverse pivot joint is preferably located forwards of and above the transom. In the drive position, the first platform section extends a sufficient distance aft of the transverse transom to allow at least one propulsion unit to be accommodated underneath the first platform section. Optionally, the at least one first platform section is arranged to be angled about the first transverse pivot joint for trim adjustment when the at least one propulsion unit is in its drive position. The first and second platform sections are arranged to form a continuous longitudinal deck portion when the at least one propulsion unit is in its drive position.
According to one example, the at least one first platform section is arranged to be angled upwards and forwards relative to the first transverse pivot joint when the at least one propulsion unit is displaced to its tilted position. Further, the second platform section is arranged to be angled upwards and rearwards relative to the second transverse pivot joint when the at least one propulsion unit is displaced to its tilted position. The angled first and second platform sections can then form a transverse seating unit when the at least one propulsion unit is in its tilted position.
According to a further example, individual first and second platform sections form a transverse seating unit for each propulsion unit when that propulsion unit is in its tilted position. In this way, separate portions of the platform arrangement can be folded one at the time, or all at once, to form separately adjustable seating units located side-by-side. Hence, a platform arrangement comprising two or more propulsion units would provide a longitudinally split platform with a number of seating units corresponding to the number of propulsion units. According to a further alternative, each portion of the platform arrangement can be provided with two or more propulsion units. The number of propulsion units and subdivisions of the platform arrangement is selected depending on factors such as available space below the platform, the size of the motors used and the size of the vessel.
In both examples, each of the first and the second platform sections forming one or more transverse seating units are individually adjustable, in the same way as a recliner chair. Consequently, the first platform section is folded upwards to an angle of up to about 80° from a horizontal plane and the second platform section is folded upwards to an angle of up to 45° from a horizontal plane when the platforms are deployed as a seating unit. The respective first and second pivot joints are preferably arranged in parallel, but can optionally also be arranged coaxially. In the latter case, opposing end portions of the first and second platform sections would be partially overlapping side-by side and be pivoted about the same axis.
According to a further example, the first platform section is folded upwards to an angle of 90-180° from a horizontal position into a position for servicing of the at least one propulsion unit. This involves pivoting the propulsion unit past its tilted position into a servicing, or maintenance position. For instance, pivoting the propulsion unit to an angle around 90° can provide easy access to the propulsion unit for general maintenance or for replacing parts thereof, such as a propeller. Pivoting the propulsion unit to an angle of 180° can be an option when the entire propulsion unit must be removed or exchanged, as the fastener means attaching the propulsion unit to the underside of the first platform section can be removed safely prior to lifting the propulsion unit off the vessel. In the case where the first and second pivot joints are arranged in parallel, the pivot joint of the first platform section could be provided with a suitable release mechanism to allow pivoting to 180°. For a coaxial solution, a common pivot axis would have to be located above the plane of the adjacent platform sections.
According to a further example, the at least one propulsion unit attached to the first platform section can preferably, but not necessarily, comprise an electric drive unit. Such an electric drive unit can in turn comprise one or more electric motors.
According to a second aspect of the invention, the invention relates to a marine vessel provided with a stern platform arrangement as described in the above examples.
The platform arrangement according to the invention solves the problem of providing a stern drive or outdrive with electric propulsion without requiring significant modifications of the hull or transom of a vessel. In most cases the outdrive can advantageously be provided with a drive housing having the same or approximately the same shape and size as a conventional stern drive housing. 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.
A further advantage is that the mounting of one or more propulsion units to a pivoting platform arrangement provides easy access to the propulsion unit for maintenance or for replacing parts thereof, such as a propeller. Pivoting the platform arrangement and the attached propulsion unit to an angle of 180° facilitates removal or exchange of the entire propulsion unit, as the fastener means attaching the propulsion unit to the underside of the first platform section can be removed safely prior to lifting the propulsion unit off the vessel. Thus, the vessel does not need to be lifted from the waters when performing service to the propulsion units.
A further advantage is that the foldable platform arrangement doubles as a seating unit when the one or more propulsion units are placed in a tilted position. On relatively small vessels, such as day cruisers and similar, the use of non-fixed seats is neither safe nor practical. At the same time, a user wearing a wet swimsuit may not want to use the standard upholstered seats. Integrating seating units into a platform arrangement such as a swim platform solves the problem of providing additional seating that is both water repellant and durable.
In this way the first and second platform sections are foldable relative to each other about their respective first and second pivot joints. The first and second platform sections are also individually foldable. A split platform arrangement allows the backrest portion and the seat portion of adjacent seating sections to be adjusted individually to desired angles.
A further advantage of the invention is that the provision of a planetary gear set allows relatively small, high speed electric motors to be used while maintaining a sufficient level of torque to the gearbox and propeller/-s. A planetary gear set can be accommodated within the cavitation plate, the stern drive can be kept relatively compact. The electric motors can drive the propellers together, independently or in variable combinations in response to different torque and power demands whereby the efficiency of the propulsion unit is improved. By allowing independent operation of at least a single motor the arrangement provides a redundancy for the propulsion unit and ensures that the vessel can be operated even if one or more electric motors are inoperable.
Further advantages and advantageous features of the invention 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 invention cited as examples. In the drawings:
The propulsion unit 101 in
Although the example in
In their respective angled positions, the angled first and second platform sections 111, 112 form a transverse seating unit when the propulsion unit 101′ is in its tilted position. The angled first and second platform sections 111, 112 are individually adjustable by a user into desired seating positions, in the same way as a reclining chair. For instance, when used as a seat, the first platform section 111 can be folded steplessly upwards to an angle α of 80° from a horizontal plane to form a backrest, while the second platform section 112 can be folded steplessly upwards to an angle ß of 45° from a horizontal plane to form a leg rest when deploying the seating unit. As shown in
In addition, the actuator 121 used for maneuvering the first platform section 111 can also be operated to angle the first platform section 111 about the first transverse pivot joint for trim adjustment, or tilt trim, of the propulsion unit 101 when it is in its drive position and operated to propel the vessel. The trim adjustment about the first transverse pivot joint 113 is schematically indicated by the arrow T in
In their respective angled positions, the angled left-hand side first and second platform sections 211, 212 form an individual transverse seating unit when the first propulsion unit 201 is in its tilted position. The angled first and second platform sections 211, 212 are individually adjustable by a user into desired seating positions in a similar way as that described for the single seating unit in
The right-hand side first and second platform sections can be displaced to form a transverse seating unit in the same way as the left-hand side first and second platform sections 211, 212 described above. The relative angles of the transverse seating units can be selected freely by the user, within the limits of a number of controllable actuators connected to the different sections of the seating units. Each side-by-side seating unit is provided with a set of maneuvering actuators as described for
It is to be understood that the present invention 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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20203289.2 | Oct 2020 | EP | regional |