MARINE PROPULSION SYSTEM WITH A MOVABLE SWIM PLATFORM

A propulsion system for a marine vessel includes a drive unit and a transom bracket for movably attaching the drive unit to the marine vessel such that the drive unit may be moved between a lower position and a higher position. The drive unit is adapted to be connected to the swim platform such that at least a portion of the swim platform is manoeuvrable by the drive unit being moved between its lower and higher positions.

TECHNICAL FIELD

The disclosure relates generally to marine propulsion. In particular aspects, the disclosure relates to a propulsion system for a marine vessel that comprises a swim platform. The disclosure can be applied to marine vessels, such as water crafts, motorboats, work boats, sport vessels, sailboats, boats, ships, among other vessel types. Although the disclosure may be described with respect to a particular vessel, the disclosure is not restricted to any particular vessel.

BACKGROUND

Marine vessels may be provided with a swim platform and one or more drive units to propel the marine vessel in water. There exist various solutions for attaching the swim platform and suspending the drive unit(s).

Prior art solutions are marred with various drawbacks such as limited swim platform accessibility, poorly suspended drive unit(s) and/or bulky, complex and high-cost designs.

SUMMARY

According to a first aspect of the disclosure, there is provided a propulsion system for a marine vessel comprising a swim platform, the propulsion system comprising a drive unit and a transom bracket for movably attaching the drive unit to the marine vessel such that the drive unit may be moved between a lower position and a higher position, wherein the drive unit is adapted to be connected to the swim platform such that at least a portion of the swim platform is manoeuvrable by the drive unit being moved between its lower and higher positions.

The first aspect of the disclosure may seek to provide a highly accessible swim platform, as the swim platform may be manoeuvred in a manner that allows a person to enter or exit the vessel from water or a dock or pier or similar. A technical benefit may include that the drive unit is rigidly suspended by being attached to the vessel by means of the transom bracket, while the drive unit at the same time may be utilised to manoeuvre the swim platform, or at least a portion thereof. In other words, the drive unit is movably attached to the marine vessel and the swim platform is movable by means of the drive unit. The swim platform, or portion thereof, is movably attached to the vessel and its movement may be accomplished by a movement of the drive unit. In addition, or alternatively, the drive unit may be movable to a position above at least a portion of the swim platform for inspection and service of the drive unit. Furthermore, the swim platform, or portion thereof, may be manoeuvred to be arranged in a position such that is may function as a backrest.

By the swim platform being manoeuvrable may be meant that the swim platform is movable, for example may be raised and lowered and/or turned. If the swim platform may be turned, it may typically be turned about an axis that extends port to starboard. By the swim platform being manouvrable may be meant that a portion of the swim platform, such as a hatch, is movable with respect to the remaining portion of the swim platform. Such a remaining portion, i.e. the swim platform excluding the hatch, may be stationary.

Optionally, the swim platform may comprise an essentially flat upper side. Thus, the swim platform may be free from steps or similar height differences.

Optionally, at least a portion of the swim platform may be raised and lowered by means of the connection to the drive unit. Such a portion may be a hatch. Optionally, the entire swim platform may be raised and lowered by means of the connection to the drive unit.

Optionally, the portion of the swim platform is carried by the drive unit. For example, the drive unit may form the only load-bearing connection between said portion and the marine vessel.

Optionally, the swim platform is carried by the drive unit. For example, the drive unit may form the only load-bearing connection between the swim platform and the marine vessel.

Optionally, the drive unit comprises a drive platform interface for connection to the swim platform. A technical benefit may include that the swim platform or a portion thereof may be securely attached to the drive unit. For example, the drive unit may push the platform (portion) upwards and pull the same downwards. The drive platform interface of the drive unit may be referred to as a platform interface.

Optionally, the drive platform interface of the drive unit is configured for connection to a platform drive interface of the swim platform. A technical benefit may include that the swim platform or a portion thereof may be securely attached to the drive unit. The swim platform may be adapted for connection to the drive platform interface. The platform drive interface of the swim platform may be referred to as a drive interface.

Optionally, the drive platform interface of the drive unit and the platform drive interface of the swim platform are configured to engage in a positive fit connection. Such a connection may be particularly secure and sturdy. Further, the positive fit connection may keep the swim platform, or a portion thereof, connected to the drive unit at all times. For example, the positive fit connection may keep the swim platform, or a portion thereof, connected to the drive unit in windy conditions and harsh sea conditions. The positive fit connection may be beneficial for durability, ensuring low noise and safety, as the swim platform, or a portion thereof, is kept in place.

Optionally, the drive platform interface and the platform drive interface are configured for sliding engagement. A technical benefit may include that at least a portion of the swim platform may be manoeuvrable by the drive unit while a mutual sliding movement is allowed. For example, said portion may be a hatch and the drive unit may pivot the hatch about a hinge axis while the drive does not pivot about the hinge axis. Instead, the drive unit may pivot about an axis that is parallel to the hinge axis, or may perform a translatory and rotary movement.

Optionally, the propulsion system comprises a connecting arm that comprises a first pivot joint connected to the drive unit and a second pivot joint connected to the transom bracket. A technical benefit may include that drive unit may be trimmed in different trim angles of the drive unit independently of water depth. Additionally, the drive unit may be moved up and down as well as translated rearwards in relation to the transom bracket while maintaining a desired thrust angle. Thus, the propulsion system may allow for a reduced draft and manoeuvring in shallow waters e.g. close to beaches. A further technical benefit may include a compact, sturdy and cost-effective design.

Optionally, the propulsion system is configured such that the drive unit may be raised and lowered by pivoting the connecting arm about the second pivot joint that is connected to the transom bracket. Thus, advantageously, the connecting arm together with the drive unit may e.g. be raised above the water line of the vessel. The second pivot joint may be aligned with an essentially horizontal axis. The second pivot joint may be aligned with an axis that may be referred to as a tilt axis.

Optionally, the propulsion system is configured such that the drive unit may be raised, by pivoting of the connecting arm about the second pivot joint, to a position above the water line of the marine vessel, and optionally to a position vertically higher than the swim platform. In other words, to a position that is vertically higher that the vertical position of the swim platform when the drive unit is in a lower or lowest position. If the drive unit may be raised vertically higher than the water line, marine growth on the drive unit may be minimised. If the drive unit may be raised vertically higher than the swim platform, visual inspection of the drive unit may be facilitated.

Optionally, the propulsion system is configured such that a thrust angle of the drive unit may be controlled by pivoting the drive unit about the first pivot joint of the connecting arm. The first pivot joint may be aligned with an essentially horizontal axis. The first pivot joint may be aligned with an axis that may be referred to as a trim axis.

Optionally, the swim platform comprises a hatch to which the drive unit is adapted to be connected, and the portion of the swim platform that is manoeuvrable by the drive unit is the hatch. Thus, there may be provided a propulsion system for a marine vessel comprising a swim platform with a hatch, the propulsion system comprising a drive unit and a transom bracket for movably attaching the drive unit to the marine vessel such that the drive unit may be moved between a lower position and a higher position, wherein the drive unit is adapted to be connected to the swim platform such that the hatch is manoeuvrable by the drive unit being moved between its lower and higher positions. A technical benefit may include that the drive unit and the hatch may be movable to a position that is vertically higher than the remaining (stationary) portion of the swim platform. Advantageously, the swim platform may comprise an essentially flat upper side when the hatch is closed (drive unit in lower or lowest position).

Optionally, the drive unit comprises a support part and a thrust part, wherein the thrust part is rotatable with respect to the support part about a steering axis to direct the thrust of the drive unit. A technical benefit may include that the design of the above described transom bracket and other components may be simplified, as the thrust may be directed by rotating the thrust part with respect to the support part. In other words, the drive unit need not be movably attached to the vessel to allow for directing the thrust for steering purposes. The support part may be adapted to be connected to the swim platform. In this manner, there is no need for a link arrangement or similar to connect the drive unit to the swim platform in a manner that allows the entire drive unit to rotate about a steering axis.

Optionally, the drive unit comprises an electric propulsion motor. Thus, the propulsion system may be an electric propulsion system. The propulsion system may be a forward or a rearward drive propulsion system. For example, the propulsion system may be a forward drive electric propulsion system. If the drive unit comprises a support part and a thrust part that is rotatable with respect to the support part about a steering axis to direct the thrust of the drive unit, the propulsion system may be a forward and rearward drive propulsion system. Thus, the propulsion system may be a forward and rearward drive electric propulsion system. The drive unit may comprise one propeller or two contra-rotating propellers.

Optionally, the propulsion system is configured such that the drive unit is tiltable about a tilt axis and trimmable about a trim axis that is separate from the tilt axis. A technical benefit may include that drive unit may be trimmed in different trim angles independently of water depth. Additionally, the drive unit may be moved up and down as well as translated rearwards in relation to the transom bracket while maintaining a desired thrust angle. Thus, the propulsion system may allow for a reduced draft and manoeuvring in shallow waters e.g. close to beaches. In addition, the swim platform may be moved up and down and turned, to be positioned and oriented to provide accessibility.

According to a second aspect of the disclosure, there is provided a marine vessel comprising the propulsion system described herein. Advantages of the second aspect of the disclosure correspond to those of the first aspect.

DETAILED DESCRIPTION

The inventive concept of the present disclosure involves connecting a drive unit, which is attached to a marine vessel by means of a transom bracket, to a swim platform such that at least a portion of the swim platform is manoeuvrable by the drive unit.

FIGS.1and2show an exemplary propulsion system1for a marine vessel60. The propulsion system1comprises a drive unit10and a transom bracket20for attaching the drive unit10to the marine vessel60. A stern of a marine vessel60comprising a transom to which the transom bracket20is secured, as well as a swim platform70with a hatch72, are also schematically illustrated.FIG.1illustrates the drive unit10in a highest, tilted up, position whereasFIG.2illustrates the drive unit in a position between its lowest and highest positions.

The transom bracket20is configured to movably attach the drive unit10to the vessel60such that the drive unit10may be moved between a lower and a higher position. In the present examples, the drive unit is connected to the hatch72of the swim platform70such that the hatch72is manoeuvrable by the drive unit10being moved between its lower and higher positions. In undepicted examples, the entire swim platform70may be manoeuvrable by the drive unit10.

As is best shown inFIG.1, the present propulsion system1comprises a first actuator40for moving the drive unit10. In the present examples, the first actuator40is arranged to tilt (pivot) the drive unit10about a first axis A (tilt axis). The first actuator may be referred to as a tilt actuator40. Further, the present propulsion system1comprises a second actuator50for moving the drive unit10. In the present examples, the second actuator50is arranged to trim (pivot) the drive unit10about a second axis A1(trim axis, denoted inFIG.2). The second actuator may be referred to as a trim actuator50.

In this context, trimming a drive unit may typically involve adjusting its thrust angle a few degrees about a neutral trust angle. Tilting a drive unit may typically involve lifting at least a part of the drive unit above the water line of the marine vessel.

In undepicted examples, the propulsion system may comprise alternative arrangements for moving, e.g. trimming and/or tilting, the drive unit. For example, there may be one single axis about which the drive unit may be pivoted, e.g. trimmed and/or tilted.

The first and second actuators40,50may be linear actuators such as hydraulic or pneumatic cylinders or electric actuators. In the present example, there are two trim actuators50connected in parallel (seeFIG.1).

As is indicated, the hatch72may be raised and lowered by means of the connection to the drive unit10, and the hatch72may also be turned around a horizontal axis by means of the connection to the drive unit10. In the depicted example, the hatch72is carried by the drive unit10.FIG.1andFIG.2illustrate the hatch72in two separate angular orientations in which the hatch72may serve as a backrest.

As is to be apprehended, if an entire swim platform70is manoeuvrable by the drive unit10, the entire swim platform70may be raised and lowered and turned by means of the present propulsion system1. In some examples, the propulsion system may comprise two drive units10, which together support one swim platform70. As is to be apprehended, the entire swim platform70could be manoeuvred to serve as a backrest.

Referring in particular toFIG.2, the drive unit10may comprise a drive platform interface15for connection to the hatch72of the swim platform70. Correspondingly, the hatch72of the swim platform70may comprise a platform drive interface75for connection to the drive platform interface15. In the present example, even though not shown in detail, the drive platform interface15and the platform drive interface75are configured to engage in a positive fit connection.

Now, the drive platform interface15and the platform drive interface75may be securely attached to one another such that the drive unit10carries hatch72, as is disclosed inFIG.1. In undepicted examples, the drive platform interface15may be securely attached to the entire swim platform70(lacking a hatch72). The drive unit10is rigidly suspended by the transom bracket20, and is thus capable of carrying the hatch72(or the entire swim platform70).

As is schematically denoted (hollow dashed arrows) inFIG.2, the drive platform interface15and the platform drive interface75may alternatively be configured for sliding engagement. Such a solution may be beneficial should the hatch72be hinged (not shown) to a stationary portion of the swim platform70or to the vessel60. Especially when the drive unit10is suspended by the transom bracket20in a manner that allows a translatory and a rotatory movement of the drive unit10with respect to the vessel60.

In the present example, even though not shown in detail, the drive platform interface15protrudes from the drive unit10towards the hatch72. In some detail, the drive platform interface15may be adapted to stably support the hatch72. For example, as may be understood fromFIG.1, the drive platform interface15may extend along at least ⅔ of the width (port to starboard) of the hatch72, or the drive platform interface15may support the hatch at two support points that are separated at least ⅔ of the width of the hatch72.

The drive platform interface15may extend through a cowling or cover of the drive unit10, and be secured to an internal, load-bearing, component of the drive unit10, which internal component is in turn secured to the transom bracket20. Typically, such a component is made of metal, and may form part of a chassis structure of the drive unit10. Alternatively, the cowling of the drive unit10may be of sufficient structural strength to stably support the hatch72. For example, the cowling made be made of metal or a fiber reinforced polymer, optionally with an internal strengthening rib-structure.

In undepicted examples where the drive unit10does not support a hatch72but instead a complete swim platform70, the drive platform interface15of the drive unit10may be adapted to support swim platform70at multiple support points that are separated along the width of the swim platform70.

The hatch72may be hinged to a stationary portion of the swim platform70and may be pivotable (about the hinge) between an open position and a closed position. When the drive unit10is tilted down, the hatch may be in its closed position and the swim platform may comprise an essentially flat upper side. Now, if the drive unit is tilted up, the hatch72may be pivoted to its open position. The propulsion system1and the swim platform70may be configured such that the drive unit10may be tilted up such that the entire drive unit10is located above the water line of the vessel60. In this way, marine growth on the drive unit10may be minimised. The propulsion system1and the swim platform70may be configured such that the drive unit10may be tilted up such that the entire drive unit10is located above stationary portion of the swim platform70. In this way, drive unit10inspection and service may be facilitated. For example, a person may stand or sit on the stationary portion of the swim platform70and visually inspect the drive unit10.

The propulsion system1may, as is shown, comprise a connecting arm30that comprises a first pivot joint31and a second pivot joint32. The connecting arm30may be elongated. The connecting arm30may comprise the respective pivot joints31,32at is opposing ends. The first pivot joint31may be connected to the drive unit10and the second pivot joint32may be connected to the transom bracket20.

The propulsion system1may be configured such that the drive unit10may be raised and lowered by pivoting the connecting arm30about the second pivot joint32that is connected to the transom bracket20. Such a pivoting motion about the second pivot joint32(coaxial with tilt axis A) is illustrated by an arc-shaped double headed arrow inFIG.2. Raising and lowering the drive unit10, e.g. by pivoting the connecting arm30about the second pivot joint32, may be referred to as tilting the drive unit10. As is shown inFIG.1, the tilt actuator40may be arranged to pivot the connecting arm30about its second pivot joint32. One end of the tilt actuator40may be connected to the transom bracket20and an opposite end of the tilt actuator may be connect to the connecting arm30, at a lever distance from the second pivot joint32.

Referring toFIG.1, the propulsion system1may be configured such that the drive unit10may be raised (i.e. tilted), by pivoting of the connecting arm30about the second pivot joint32(tilt axis A), to a position above swim platform70. More precisely to a position that is vertically higher that a lowest position of the swim form70. The lowest position of the swim platform70may be a position in which the swim platform70is located during normal operation of the propulsion system, i.e. when the drive unit10is tilted down and propels the vessel60in water.

Referring in particular toFIG.2, in the present propulsion system1the trim angle of the drive unit10is controlled by pivoting the drive unit10about the first pivot joint31(trim axis A1) of the connecting arm30. The trim actuator50is arranged to pivot the drive unit10about the first pivot joint31.

The present drive unit10comprises a support part10aand a thrust part10b. When the drive unit10is in its tilted down position, the support part10ais the upper part and the thrust part10bis the lower, or submerged, part. The support part10amay also be at least partly submerged when the drive unit is tilted down. The thrust part10bis rotatable with respect to the support part10aabout a steering axis B to direct the thrust of the drive unit10. As is to be apprehended, when the thrust part10bis rotated about the steering axis B, the thrust may be selectively directed in an essentially horizontal plane. The steering axis B is essentially vertical when the drive unit10is in a position to propel the vessel (the drive unit being completely or at least partially tilted down).

The drive unit10may comprise an electric propulsion motor, thus the propulsion system1may be an electric propulsion system.

Also disclosed are examples according to the following clauses:1. A propulsion system (1) for a marine vessel (60) comprising a swim platform (70), the propulsion system (1) comprisinga drive unit (10) anda transom bracket (20) for movably attaching the drive unit (10) to the marine vessel (60) such that the drive unit (10) may be moved between a lower position and a higher position,wherein the drive unit (10) is adapted to be connected to the swim platform (70) such that at least a portion of the swim platform (70) is manoeuvrable by the drive unit (10) being moved between its lower and higher positions.2. The propulsion system (1) of clause1, configured such that at least a portion of the swim platform (70), optionally the entire swim platform (70), may be raised and lowered by means of the connection to the drive unit (10).3. The propulsion system (1) of clause2, configured such that at least a portion of the swim platform (70), optionally the entire swim platform (70), may be turned around a horizontal axis by means of the connection to the drive unit (10).4. The propulsion system (1) of any preceding clause, wherein at least the portion of the swim platform (70) is carried by the drive unit (10).5. The propulsion system (1) of clause4, wherein the drive unit (10) forms the only load-bearing connection between the swim platform (70) and the marine vessel (60).6. The propulsion system (1) of any preceding clause, wherein the drive unit (10) comprises a drive platform interface (15) for connection to the swim platform (70).7. The propulsion system (1) of clause6, wherein the drive platform interface (15) of the drive unit (10) is configured for connection to a platform drive interface (75) of the swim platform (70).8. The propulsion system (1) of clause7, wherein the drive platform interface (15) and the platform drive interface (75) are configured to engage in a positive fit connection.9. The propulsion system (1) of clause8, wherein the drive platform interface (15) and the platform drive interface (75) are configured for sliding engagement.10. The propulsion system (1) according to any of clauses7to9, wherein the drive platform interface (15) protrudes from the drive unit (10) towards the swim platform (70) and/or the platform drive interface (75) protrudes from the swim platform (70) towards the drive unit (10).11. The propulsion system (1) of clause10, wherein the drive platform interface (15) protrudes from the drive unit (10) and is received in a platform drive interface (75) in the form of a slot, or the platform drive interface (75) protrudes from the swim platform (70) and is received in a drive platform interface (15) in the form of a slot.12. The propulsion system (1) of any preceding clause, comprising a connecting arm (30) that comprises a first pivot joint (31) adapted to be connected to the drive unit (10) and a second pivot joint (32) adapted to be connected to the transom bracket (20).13. The propulsion system (1) of clause12, configured such that the drive unit (10) may be raised and lowered by pivoting the connecting arm (30) about the second pivot joint (32) of the connecting arm (30).14. The propulsion system (1) of clause13, configured such that the drive unit (10) may be raised, by pivoting of the connecting arm (30) about its second pivot joint (32), to a position above the water line of the marine vessel (60).15. The propulsion system (1) clause13, configured such that the drive unit (10) may be raised, by pivoting of the connecting arm (30) about its second pivot joint (32), to a position vertically higher than a portion of the swim platform (70).16. The propulsion system (1) according to any of clauses12to15, comprising a first actuator (40) that is arranged to pivot the connection arm (30) about the second pivot joint (32).17. The propulsion system (1) according to any of clauses12to16, configured such that a thrust angle of the drive unit (10) may be controlled by pivoting the drive unit (10) about the first pivot joint (31) of the connecting arm (30).18. The propulsion system (1) of clause17, comprising a second actuator (50) that is arranged to pivot the connection arm (30) about the first pivot joint (31).19. The propulsion system (1) of any preceding clause, wherein the swim platform (70) comprises a hatch (72) to which the drive unit (10) is adapted to be connected.20. The propulsion system (1) of clause19, wherein the portion of the swim platform (70) that is manoeuvrable by the drive unit (10) is the hatch (72).21. The propulsion system (1) of clause20, wherein the hatch (72) is carried by the drive unit (10).22. The propulsion system (1) of clause19, wherein the hatch (72) is hinged to the swim platform (70) or to the marine vessel (60).23. The propulsion system (1) of clause22, wherein the hatch (72) and the drive unit (10) are configured for sliding engagement.24. The propulsion system (1) of any preceding clause, wherein the drive unit (10) comprises a support part (10a) and a thrust part (10b), wherein the thrust part (10b) is rotatable with respect to the support part (10a) about a steering axis (B) to direct the thrust of the drive unit (10).25. The propulsion system (1) of clause24, wherein the support part (10a) is adapted to be connected to the swim platform (70).26. The propulsion system (1) of clause24or25, wherein the support part (10a), in relation to the vessel (60), is only movable between its lower and higher positions.27. The propulsion system (1) of any preceding clause, configured such that the drive unit is tiltable about a tilt axis (A).28. The propulsion system (1) of any preceding clause, configured such that the drive unit is trimmable about a trim axis (A1) that is separate from the tilt axis (A).29. The propulsion system (1) of any preceding clause, comprising two drive units (10), both drive units being adapted to be connected to the swim platform (70).30. A marine vessel (60) comprising a propulsion system (1) according to any preceding clauses.31. The marine vessel (60) of clause30, comprising a swim platform with a hatch (72), wherein the drive unit (10) is adapted to be connected to the hatch (72) such that the hatch (72) is manoeuvrable by the drive unit (10) being moved between its lower and higher positions.