RECEPTACLE

Field

[001] The present disclosure relates to floatable vessels having an object collection receptacle, and more particularly to floatable vessels having a power operated object collection receptacle.

Background

[002] Floatable vessels having an object collection receptacle are useful, for example, for rescue or for collecting objects from water. Conventional vessels for on-water applications typically use internal combustion engines to drive propellers to propel the vessels and to supply other operation power. Internal combustion engines are not environment friendly and can be dangerous since highly flammable fuels are required.

Disclosure

[003] The vessel according to the disclosure comprises an electric driving apparatus for propelling the vessel and an electrically operated object collection receptacle.

[004] There is disclosed a water floatable vessel comprising a water floatable main body, an object collection receptacle, a movement mechanism for moving the object collection receptacle into and out of water when the main body floats on water, at least an electric engine for moving the main body relative to the water on which the main body floats, a stored power apparatus for supplying electrical energy to operate the jet engine and a power charger for charging the stored power source; wherein the vessel comprises an object capture compartment which is formed by cooperation of the main body and the object collection receptacle, wherein the object collection receptacle forms a perforated and movable floor of the object capture compartment and has an object access aperture defined on an object approaching end of the main body, and wherein the main body extends along a longitudinal direction and defines a through bore which extends in the longitudinal direction to define length of the object capture compartment.

[005] The water has a water surface and the movement mechanism may be operable to move the object collection receptacle between a lowered position which is a submerged position below the water surface and a lifted position which is above the water surface. The electric engine may comprise a jet outlet which is to eject a jet stream horizontally in a horizontal direction which is parallel to the water surface or at an elevation angle to the water surface. The elevation angle may be variable. [006] The electric engine may be operable to eject a jet stream in the longitudinal direction and/or to eject a jet stream at an ejection angle to the longitudinal direction. The ejection angle is variable.

[007] The electric engine maybe an electric jet engine. The electric jet engine may be an electric air jet engine which is to operate to eject a jet stream of air or an electric water jet engine which is to operate to eject a jet stream of water.

[008] The electric engine may be operable to tilt the main body so that a forward end of the object collection receptacle, which is an end proximal the object approaching end is lifted or lowered.

[009] The electric engine may be installed on the main body at a distal end of the main body, the distal end being an end distal to the object approaching end.

[010] The electric engine may comprise a main housing, the main housing having a jet-inlet, a jet- outlet and a closed fluid path interconnecting the jet-inlet and the jet-outlet; and one turbine fan wheel or a plurality of turbine fan wheels enclosed inside the main housing for moving a driving fluid through the fluid path with turbine acceleration.

[01 1] The main housing may comprise a directional fluid guide which is in abutment with the jet- outlet and which sets direction of jet stream at the jet-outlet. The fluid guide may comprise a titling vane and/or a steering vane. The tilting vane is to control tilting of the main body about a transverse axis which is orthogonal to the longitudinal axis and the steering vane is to steer the vessel to move at an angle to the longitudinal direction.

[012] The jet-outlet of the electric engine may be submerged under water.

[013] The vessel may comprise a first electric engine and a second electric engine. The first electric engine and the second electric engine are to cooperate to propel the vessel and/or to change course of the vessel and or to change titling of the main body and titling of the object collection receptacle about a transverse axis which is orthogonal to the longitudinal direction.

[014] The vessel may comprise an equipment compartment inside which the stored power apparatus is stored. The power charger may comprise a charging circuit which is electrically connected to the stored power apparatus and a power-coupling surface for wireless-coupling incoming electric power from a power source to the charger circuit. The power-coupling surface may form part of a peripheral wall of the equipment compartment or may be immediately behind the peripheral wall which is a magnetic permeable wall.

[015] The power-coupling surface may comprise a power-coupling winding for wirelessly receiving power transmitted from a charging source. [016] The power coupling surface may be formed on a retracted end of a charging compartment, and a power charging head is to enter the charging compartment to facilitate power charging during charging operations.

Figures

[017] The present disclosure is described by way of example and with reference to the accompanying figures, in which:

Figure 1 A is a top plan view of an example vessel of the present disclosure,

Figure 1 B is schematic perspective view of the example vessel of Figure 1A with an example object collection receptacle at an intermediate position which is intermediate a top position and a bottom position,

Figure 1 C is schematic perspective view of the example vessel of Figure 1A with the example object collection receptacle at the bottom position,

Figure 1 D is schematic perspective view of underside of the example vessel of Figure 1 A

Figure 2 is a perspective view of an example electric engine of the example vessel of Figure 1 A,

Figure 2A is an exposed view of the example electric engine of Figure 2,

Figure 2B is a block diagram of the example electric engine,

Figures 3A and 3B show configurations of example energy pick-up windings,

Figure 4A is a block diagram showing charging connection for charging the stored power apparatus of the example vessel,

Figure 4B is a schematic view showing a primary portion and a secondary portion of a power charging system in a wireless power transfer operation mode,

Figure 4C is a schematic view showing the primary portion detached from the secondary portion of the power charging system of Figure 4B,

Figure 4D is an exploded view of the power charging system of Figure 4B, and

Figure 5 shows example controlled-operation flows of the example vessel.

Description

[018] An example vessel comprises a vessel main body, a support platform mounted on the main body, a control panel 103 on the support platform, an objection collection receptacle comprising a movable platform 101 , a powered vessel-driving arrangement, and a stored power apparatus 104 for driving the powered vessel-driving arrangement, as depicted in Figures 1A, 1 B, 1 C and 1 D.

[019] The main body is a floatable body having a forward end, a rearward end and lateral sides. A rescue compartment is defined between the forward end of the main body and the support platform. The rescue compartment, as an example of object collection compartment, comprises a base portion which is defined by the movable platform and a forward portion which is a forward aperture delimited by the forward end of the main body. The rescue compartment has lateral sides which are defined by internal lateral sides of the main body. The forward end of the main body is an object approaching end of the main body in this example.

[020] The example vessel is in the form of a catamaran, comprising a first floatable body 105a and a second floatable body 105b which cooperate to define the main body. Each floatable body is an elongate body defining a hull such that the first floatable body 105a defines a first hull and the second floatable body 105b defines a second hull. Each hull is elongate and extends along a longitudinal direction defined by a longitudinal axis which is also a center axis of the hull. The first and second hulls are interconnected by the support platform. The first and second hulls are interconnected by the support platform such that they are parallel with their longitudinal axes parallel and space apart and with their respective longitudinal ends aligned. The first and second hulls are fastened to the support platform and the support platform is made of a strong material such as hard plastics to maintain structural integrity of the vessel. The two hulls cooperate to define a through channel extending from the forward end to at least the support platform. The width of the through channel is approximately equal to the parallel separation between the first hull and the second hull. The hull may be hollow or may be formed of a floatable material such as polystyrene. The first and second hulls are approximately of equal length and cooperate to define the length as well as the width or lateral extent of the vessel.

[021] The main body comprises at least an equipment compartment. The example equipment is formed underneath the support platform and comprises a watertight compartment. An on-board battery pack and a battery charger and other control equipment are stored inside the watertight compartment. In some embodiments, the vessel may comprise a roof and a solar panel mounted on the roof top. The solar panel may provide additional power for battery charging and/or drive operations. The roof is directly above the support platform to provide shading to operators of the vessel and/or person(s) or object(s) rescued. In example embodiments such as the present, the main body comprises a first equipment compartment which is formed inside the first hull and a second equipment compartment which is formed inside the second hull. The example stored power apparatus comprises a first battery pack 104a which is stored in the first equipment compartment and a second battery pack 104b which is stored in the second equipment compartment. The first and second equipment compartment are adjacent to the support platform, and are preferably located at the same longitudinal location of the main body for good balance. The battery packs are to function as ballasts to enhance stability of the vessel as well as a stored power source.

[022] The movable platform 101 is movable relative to the main body, for example, moveable upwards and downwards relative to the main body. In example embodiments, the movable platform 101 is also forwardly movable and rearwardly movable relative to the main body or the support platform.

[023] In example embodiments, the movable platform 101 , as an example object collection receptacle, comprises a receptacle which is an object receptacle such as a rescue net. The net may be a flexible net mounted on a rigid and robust outer-frame or a rigid net made of a solid material with soft- and water-resistant cushioning. The flexible net may be woven or formed by weaving high-strength and water-resistant fibers such as nylon fibers. The rigid net may be molded of plastic which may have a cushioned surface. The cushioned surface is upward-facing and the cushioning material may be polystyrene or other soft and water-resistant materials. In general, the rescue net is strong enough to hold at least 150kg to 250kg, which is the weight of one or two persons or more. The flexible net is preferably tensioned in the longitudinal and transversal directions to mitigate distortion in the downward direction when carrying a heavy load, such as a human load. The downward direction being orthogonal to the longitudinal and transversal directions.

[024] The movable platform 101 is connected to the main body by a conveying mechanism as an example of movement mechanism. The example conveying mechanism is an electrically driven mechanical moving mechanism such as a linear actuator 102. The example linear actuator comprises an elongate stator and an electrical-powered rotor, which is to move the receptacle along the elongate stator as a rigid track. The linear stator is inclined at an angle to the support platform such that the receptacle is to move from a lower vertical level to a higher vertical level when the receptacle travels towards the support platform and vice versa, that is from a higher vertical level to a lower vertical level when the receptacle travels towards the forward end of the vessel, which is an object approaching end. Therefore, the movement mechanism may operate to move the rescue net vertically between a submerged position which is below the vessel-supporting water surface (water surface in short) and an elevated surface which is above the vessel supporting water surface. In example embodiments, the elevated surface may be flush with or at the same level as the support platform. A linear actuator is an example movement mechanism suitable for moving the object receptacle. In some embodiments, the movement mechanism may comprise a hydraulic operated arm, hydraulic operated arms, or simple mechanical driven by a gear train or a lever. The arm or arms may be connected to the support platform or the main body.

[025] The example linear stator is connected to a rear middle edge portion of the rescue net. The forward end of the rescue net is a free end which is opposite facing the forward aperture of the main body. In some embodiments, the movement mechanism may operate to move the rescue net to a forward-protruding configuration at which the rescue net protrudes beyond the forward end of the main body. When in the forward-protruding configuration, the rescue net may be submerged so that objects or people which are forward of the vessel can be captured or collected by the rescue net. After a target object has been collected, the movement mechanism may elevate the rescue net to above while in the forward-protruding configuration and while moving the rescue net rearwards towards the support platform. The example receptacle has an upper surface which is to function as a collection surface. The collection surface is substantially parallel to the water surface and can be moved upwards and downwards relative to the vessel main body.

[026] The example vessel uses electric engines as an example of powered vessel-driving arrangement. The example engines are electric jet engines 100a, 100b which are a type of electric turbines. The example vessel is propelled by a plurality of electric engines. The example electric engines are mounted at the rear end of the main body and are submerged below the vessel- support water surface during operations. The example vessel comprises a first electric jet engine 100a and a second electric jet engine 100b. The first electric jet engine 100a is mounted at the rear end of the first hull and the second electric jet engine 100b is mounted at the rear end of the second hull. Each electric engine has a driving power outlet which is submerged.

[027] The electric engines are to obtain operation power from the on-board battery pack. The vessel comprises a battery management system BMS which to control supply of electric power to the electric engine and to monitor conditions of the battery pack. The conditions to be monitored by the BMS may include electrical conditions, battery energy available, discharging rate or electric power being delivered from the battery pack, charging rate or electric power being delivered to the battery pack if the battery pack is being charged, etc., and non-electrical conditions such as battery temperature, battery state, etc. The BMS is electrically connected to the control panel so that an operator can by operating user-operable control interfaces on the control panel 103 control operations of the electric engines. In some embodiments, the vessel may comprise a drive controller for controlling engine drive. The drive controller may be a microprocessor-based control circuit. The BMS and the drive controller may share a single control circuitry and the control circuitry may be mounted inside the control panel 103.

[028] In example embodiments, the vessel may include an operator seat on the support platform so that an operator may be seated while driving the vessel or operating the receptacle. The example operator seat is elevated from the control panel 103 and the operator seat is arranged elevated from the support platform to give the operator a good view on the water surface.

[029] In example embodiments such as the present, the control panel 103 projects upwardly from the support platform and is intermediate the rescue compartment and the operator seat or the rear end of the vessel main body. A plurality of user-operable switches is distributed on the control panel 103, preferably on the surface facing the operator or the operator seat. The user-operable switches may be hard-switches or soft-switches. The soft-switches may be formed on an electronic display panel, such as an LCD touch panel to facilitate convenient control and user monitoring.

[030] In some embodiments, the vessel is to be controlled without a human operator on board. For example, by remote control, in which case the control panel 103 may include telecommunications equipment for data transmission and reception.

[031] The example electric engine is an electric jet engine 100a, 100b. The electric jet engine comprises a main housing defining a water inlet 100a_6, 100b_6, a water outlet 100a_7, 100b_7, a liquid path interconnecting the water inlet 100a_6, 100b_6 and the water outlet 100a_7, 100b_7. An electric turbine is mounted inside the main housing to move water from the water inlet 100a_6, 100b_6 to the water outlet 100a_7, 100b_7 after pressurization and acceleration by the turbine. The main housing comprises a closed liquid path and water coming in from the water inlet is accelerated by the turbine while moving along the closed liquid path and to emit as a high-speed jet stream at the water outlet to drive the vessel. The jet engine is to eject a water jet stream so that water jet stream exits in a direction substantially parallel to the water surface and at an angle to the longitudinal axis of the main body. The emission angle may be between zero degrees and plus or minus ninety degrees. When the emission angle is zero degree, the jet stream is parallel to the longitudinal axis of the main body. When the emission angle is at ninety degrees, the jet stream is orthogonal to the longitudinal axis of the main body.

[032] The water outlet of the example jet engine is a directional outlet and the direction of jet stream coming out of the water outlet is variable. The directional outlet comprises a liquid guide which extends along the direction of jet stream emission. The direction of the vessel can be controlled or changed by varying the directions of the jet streams emitted from the electric jet engines. The overall direction of the vessel is determined by the vector sum of the jet streams emitted by the electric jet engines.

[033] In example embodiments, the electric jet engine has a fixed directional outlet wherein the direction of jet stream is not variable. The direction of a vessel having a fixed directional water outlet can be controlled by varying the relative energy of water jet stream emitted from the jet engines. The energy of a water jet stream is a vector quantity determined by factors such as volume rate, speed, and direction of water jet stream.

[034] An example main housing of an example electric jet engine comprises a lower housing portion and an upper housing portion. The lower housing portion includes an inlet housing portion and an outlet housing portion adjacent to the inlet housing portion. The upper housing comprises a first turbine housing and a second turbine housing. In example embodiments such as the present, the first turbine housing is an inner chamber and the second turbine housing is an outer chamber surrounding the inner chamber. The inner chamber is defined by a substantially cylindrical inner chamber wall and the outer chamber is defined by another substantially cylindrical outer chamber wall surrounding the inner chamber. The outer chamber wall has a larger axial extent than the inner chamber and has a head room above the inner chamber. A first fan wheel is mounted inside the inner chamber, with its fan axis coaxial with the cylindrical axis of the inner chamber. The first fan wheel and the inner chamber cooperate to define a first portion of a closed liquid path inside the inner chamber. The outer chamber is defined by the outer chamber wall in cooperation with the inner chamber and defines a circular liquid path surrounding the inner chamber. A second fan wheel is mounted inside the outer chamber, with its fan axis coaxial with the cylindrical axis of the outer chamber, which is also the cylindrical axis of the inner chamber. The second fan wheel surrounds the inner chamber and with its fan blades rotating inside the circular liquid path which surrounds the inner chamber. The inlet/outlet housing comprises a water inlet and an inlet-guide interconnecting the water inlet and the inner chamber. The inlet guide extends in a direction parallel to the axial direction of the fan wheels. The inlet/outlet housing comprises a water outlet and an outlet-guide interconnecting the water outlet and the outer chamber. The outlet-guide is substantially orthogonal to the inlet-guide and extends in a direction to define a jet stream direction. Both the first and second fan wheels are driven by an electric motor. In some embodiments, the fan wheel is a permanent magnet rotor forming part of a brushless motor.

[035] An electric jet engine comprising a first turbine fan wheel driving liquid in a first liquid path defined by a first turbine chamber and a second turbine fan wheel driving liquid in a second liquid path defined by a second turbine chamber surrounding the first turbine chamber. Such an electric jet engine has a high driving power to space ratio. The inner chamber is an example of first turbine chamber and the outer chamber is an example of the second turbine chamber in this example.

[036] The electric jet engine is mounted with its water inlet and the water outlet submerged below the water surface and in liquid communication with the water floating the vessel.

[037] During operations, water floating the vessel and in proximity of the water inlet is sucked into the inner chamber. The incoming water is compressed and accelerated by the first fan wheel as a first stage turbine compressor and accelerator while moving along the inner chamber. The water compressed and accelerated by the first stage turbine then moves into the outer chamber and is further compressed and accelerated by the second fan wheel as a second stage turbine compressor and accelerator. The water after the second stage compression and acceleration is to eject as a water jet stream with sufficient power to move the vessel. The direction of movement is determined by the vectored sum of the on-board jet engines.

[038] In example embodiments such as the present, the lower housing portion is rotatable so that the direction of water outlet and consequently the direction of the outlet-guide is variable. The lower housing portion may be rotated relative to the upper housing portion with a rotation mechanism which rotates the lower housing about a rotation axis to change the direction of the outlet-guide. The direction of the outlet-guide is defined by angle between the axis of the outlet guide and the longitudinal axis of the vessel. The rotation axis in this embodiment is coaxial with the cylindrical axis of the inner chamber. In some embodiments, the rotation axis is parallel to, but offset from the cylindrical axis of the inner chamber, which is also the center axis of the main housing in this example. In some embodiments, the direction of jet stream coming out of the water outlet is not determined by the direction of the outlet-guide, but on the direction of a direction setting vane inside the outlet-guide. The changes in the direction of the jet stream define a propelling plane which is parallel to the water surface.

[039] Therefore, the electric jet engine comprises a main housing, a propelling motor, a propelling gear driven by the propelling motor to move water inside the main housing from the water-inlet to the water outlet after significant acceleration due to high internal pressurization so that the jet stream is to exit at the water outlet with high pressure and speed. The electric jet engine also comprises a direction motor and a direction gear to facilitate change of jet stream flow at the water outlet of the engine. The propelling motor may be a brushless DC motor, an induction motor, or other types of motors. The propelling gear comprises the first fan wheel and the second fan wheel in this example, but may have more or less fan wheels without loss of generality. A fan wheel comprises a plurality of vanes or blades for moving water in the direction from the water inlet to the water outlet, which is the jet outlet. The fan wheels in this example have peripherally or circumferentially distributed vanes and are similar to centrifugal fans. The vanes, or more exactly, all the vanes are hidden vanes which are enclosed inside the main housing and inside the closed liquid paths to enhance operational safety.

[040] The directional gear of the jet engine for steering the vessel may comprise one direction setting vane or a plurality of direction setting vanes. The direction setting vane is a steering vane which is disposed inside the outlet guide and the jet stream direction may be set by moving the guide to different angles with respect to the longitudinal axis of the vessel main body and with respect to a vertical plane. The vertical plane is orthogonal to a horizontal plane which is defined by the water surface. In some embodiments, the jet stream ejected from the jet engine is ejected in a direction parallel to the horizontal plane and the vanes of the directional gear. In some embodiments, the jet stream ejected from the jet engine is ejected in a direction at an angle to the horizontal plane.

[041] When the jet stream is ejected in a direction parallel to the water surface, the vessel will move or turn in a direction parallel to the water surface. When the jet stream is ejected in a direction at an angle to the water surface, the vessel will move or turn in a direction with the vessel main body titled at an angle with respect to the water surface.

[042] In order to eject a jet stream at an angle to the water surface, the outlet guide vane may be movable in a direction to change the angle of ejection with respect to the water surface to move the rear portion of the vessel main body slightly upwards or slightly downwards; and/or the vane or vanes of the directional gear may have a tilting direction setting surface to set a variable tilting angle with respect to the water surface.

[043] When the vessel main body is titled relative to the water surface, the longitudinal axis of the vessel main body is titled, the forward end of the vessel main body is titled upwards or downwards relative to its rear end. When the receptacle is titled, the receptacle, or more specifically the forward end of the receptacle or rescue net, is at a titled angle with respect to the water surface and can engage an approaching object at an engagement angle relative to the water surface.

[044] For example, when the jet stream is ejected at an angle, or more specifically at a positive acute angle, away from the water surface, the forward end of the vessel main body will be tilted downwards relative to the rear end of the vessel main body and the forward end of the receptacle will be dipped away from the water surface; and when the jet stream is ejected at an angle, or more specifically at a negative acute angle, towards the water surface, the forward end of the vessel main body will be tilted upwards relative to the rear end of the vessel main body and the forward end of the receptacle will be titled towards the water surface.

[045] Therefore, the angle of engagement of the receptacle can be adjusted or further adjusted by operating the directional gear to change the tilting angle of the jet stream direction.

[046] Where the directional gear comprises a tilting gear to vary and control the tilting of the jet stream relative to the water surface, the directional gear may comprise a tilting vane or a plurality of tilting vanes. The tilting vane may comprise a vane member having a plane which is movable between parallel to the water surface and at positive titling angles or negative tilting angles relative to the water surface.

[047] In some embodiments, the vane of the direction gear may be T-shaped or H-shaped. A T- shaped vane comprises a first vane member which is for tilt angle setting and a second member for direction setting. The first vane member as an example of a tilting vane has a tilt-angle setting plane which is pivotally movable about a transversal axis which is orthogonal to the longitudinal axis of the vessel main body. The tilt angle setting plane is pivotally rotatable about a pivot axis which is parallel to the water surface. The second vane member has a direction setting plane which is substantially vertical and pivotally movable about a vertical pivot axis for changing the angle with respect to the longitudinal axis and setting the jet stream direction. The first vane member and the second vane member may be independently controlled by the drive controller. In the H-shaped variant, a direction setting vane may be intermediate two tilting vane members or a titling vane member may be intermediate two direction setting planes.

[048] The steering of the vessel by operation of the electric engine may be by manual operation or may be computer controlled. For example, steering by differential power output of the electric engines and/or by change in direction of the steering vane may be stored as instructions for execution of a microprocessor-based computer. The vessel may also comprise sensors so that the computer can determine the extent of power, power differential and/or steering vane angle with reference to sensor feedback to steer.

[049] The tilting of the vessel by operation of the electric engine may be by manual operation or may be computer controlled. For example, tilting by change in direction of the tilting vane may be stored as instructions for execution of a microprocessor-based computer. The vessel may also comprise sensors so that the computer can determine the extent of power and/or tilting vane angle with reference to sensor feedback to tilt.

[050] In some embodiments such as depicted in Figure 2B, the electric jet engine 110a comprises a main housing, a propelling motor 100a_1 , a propelling gear 100a_2, a non-exposed propeller 100a_3 driven by the propelling motor 100a_1 via the propelling gear 100a_2, so as to move water inside the main housing from the water inlet 100a_6 to the water outlet 100a_7. The electric jet engine 110a also comprises a directional motor 100a_4 and a direction gear 100a_5 to facilitate change of jet stream flow at the water outlet 100a_7 of the engine.

[051] The stored power apparatus may comprise a battery pack which is to store electrical energy to provide operation power of the vessel. The operation power comprises drive power to move the vessel and equipment maneuver power for maneuvering equipment such as the movement mechanism for moving the receptacle and other equipment on board.

[052] The battery back comprises a plurality of battery cells connected in parallel and/or in series. The battery cells may be rechargeable battery cells such as Lithium cells. In some embodiments, the battery cells may be supercapacitors or other power storage devices without loss of generality.

[053] The vessel may include a charging port for charging the on-board stored power apparatus such as the battery pack or battery packs. The charging port may comprise a water-proof power inlet. The water-proof power inlet may be a contact-type charging port for pin-and-socket power connectors or an inductive charging port for inductive or electro-magnetic charging.

[054] An example on-board power charger comprises a charging circuit, a power conversion circuit and a power-coupling device. The charging circuit had an input which is connected to the power conversion circuit and an output which is connected to the stored powered apparatus for charging thereof. The power coupling device comprises a power coupling surface and a power output which is connected to the power conversion circuit. The example power coupling device comprises an energy pick-up winding which defines a power-coupling surface for wireless collection of electromagnetic energy and an electrical power output. The power conversion circuit comprises an AC-to-DC converter for converting AC signals at the output of the power coupling device to DC current for charging. The charging circuit is optionally controlled by an on-board BMS.

[055] Figures 3A and 3B show example configuration of power pick-up windings suitable for wireless coupling of incoming power. Each of the pick-up windings comprises a helical or a spiral coil formed on an insulated substrate. The pick-up winding may comprise a plurality of coils formed on a plurality of layers of insulated substrate for a higher power pick-up density. Depending on the shape of cores and/or enclosure, the coils may be rounded, or non-rounded or rectangular. For example, the coils may be round spiral coil 132 wound around a round metal core 133, as depicted in Figure 3A. For example, the coils may be square spiral coil 143 wound around a square metal core 135, as depicted in Figure 3B. [056] During charging operations, a charging power supply having a power transmitting head is brought into proximity of the pick-up windings for wireless charging. The charging power supply comprises a power input 119, a high frequency power generator 118 for converting the input power into a high frequency output, and a power transmitter. The power transmitter may be in the form of a power output winding which is configured to transmit power wirelessly at a high frequency, for example, in kHz range such as 20kHz to several hundred kHz such as 500kHz or in multi-MHz range. The power transmitter is to operate as a power transmission antenna and the pick-up windings are to operate as a power reception antenna to facilitate wireless power coupling between the charging power supply and the charger.

[057] The example vessel when in power charging operations during which an example power charging power supply and an example charger 120 of the vessel are to cooperate to form a power charging system to facilitate wireless electrical power transfer 115 between an external power source, for example, the AC mains, and the vessel. Referring to Figure 4A, the power pick-up windings of the on-board power charger is to function as a secondary side 117 and the power transmission windings are to function as a primary side 116 of the power charging system.

[058] The example power charging system comprises a primary portion and a secondary portion which is on-board the vessel. During charging or re-charging of the on-board power storage apparatus or to supply operation power to the vessel, the primary portion and the secondary portion of the power charging system are brought into magnetic, or more exactly electromagnetic, coupling to facilitate electrical, or more exactly, wireless electromagnetic energy transfer. Therefore, the primary portion and the secondary portion of the power charging system are brought into magnetic coupling to form a closed magnetic energy transfer circuit and cooperate to form a waterproof power transfer apparatus during charging operations.

[059] An example waterproof power transfer apparatus comprises a primary core 107, a primary winding 106 wound on the primary core 107, a secondary core 110, a secondary winding 111 wound on the secondary core 110, an enclosure 108 and a secondary frame 112. The primary winding 106 is connected to input cables 113, which are connected to the high frequency generator 118 that is connected to the AC mains 119. The secondary winding 111 is connected to output cables 114, which are connected to the charger 120 that is connected to the battery packs 104a, 104b. The primary winding 106 is wounded on the primary core 107, which is fixed in the enclosure 108. The secondary winding 111 is wound on the secondary core 110, which is fixed in the secondary frame 112. The secondary frame 112 is moveable and can move in and out from the primary core 107. The secondary frame 112 may be fixed on the support platform, in a position accessible by operator.

[060] The example secondary core 110 is an l-shaped magnetic core having a central limb and the secondary winding 111 is wound on the central limb. The l-shaped magnetic core is integrally formed of a magnetic material of high magnetic permeability, has a top portion, a bottom portion, and an intermediate portion interconnecting the top and bottom portions. The central limb extends along a central limb axis. The secondary winding 111 is wound on the central limb and consists of a plurality of winding coils each having a coil plane orthogonal to the central limb axis. The secondary winding 111 surrounds the central limb and has a central aperture defined by the central limb.

[061] The example primary core 107 is a C-shaped magnetic core and the primary winding 106 is wound on a middle limb of the C-shaped magnetic core. The C-shaped magnetic core is integrally formed of a magnetic material of high magnetic permeability, has a top limb, a bottom limb, and a middle limb. The middle limb extends along a middle limb axis. The top limb extends from a first (say, top) longitudinal end of the middle limb and projects orthogonally away from the middle limb. The bottom limb extends from a second (say, bottom) longitudinal end of the middle limb and projects orthogonally away from the middle limb and extends in the same direction as the top limb. The top limb and the bottom limb are parallel, spaced apart and cooperate to define an inter-limb space which is to function as a primary winding receptacle.

[062] The primary core 107 has a width and the width of the secondary core 110 is comparable to or matched with the width of the primary core 107. In example embodiments such as the present, the primary core 107 has a uniform width along a C-shape path defining the C-shape of the primary core 107. The height of the secondary core 110, which is measured along the axial direction of the secondary core 110 as defined by the central limb axis, is comparable to or matched with the longitudinal clearance of the primary winding receptacle. The height of the secondary core 110 and the longitudinal clearance of the primary winding receptacle are arranged to be matched so that the primary and secondary cores are in closely-fitted abutment contact when they are brought into formation of the closed magnetic circuit for power transfer. The width of the secondary core 110 and the width of the primary core 107 or the primary winding receptacle are matched to facilitate maximum power transfer efficiency and so that a complete magnetic core of the power transfer apparatus has side flush side surfaces. The example complete magnetic core has an O- shape with right angle corners. The power transfer apparatus is an electrical power transfer apparatus resembling an electrical power transformer, but having a secondary portion which is detachable from the primary portion or vice versa. The complete magnetic core comprises a top limb, a bottom limb, a first side limb and a second side limb. The first side limb and the second side limb are parallel and spaced apart, with the central limb of the secondary core 110 forming the first side limb and the middle limb of the primary core 107 forming the second side limb.

[063] During charging operations, the secondary portion is moved into proximity of the primary portion, and more specifically, moved into channel defined by a pair of parallel limbs on longitudinal ends of the middle limb of the primary core 107 to facilitate wireless power charging. During charging operations, the primary and secondary portions may be fastened using a clutch member 109. After charging is complete, the clutch member 109 is removed and the secondary portion is detached and moved away from the primary portion. The primary portion or at least the middle limb portion of the primary portion is sealed to ensure water-tightness so that no water leaks into the water tight equipment compartment when the vessel is on water.

[064] In some embodiments, the example primary core is an l-shaped magnetic core having a central limb and the primary winding is wound on the central limb. The l-shaped magnetic core is integrally formed of a magnetic material of high magnetic permeability, has a top portion, a bottom portion, and an intermediate portion interconnecting the top and bottom portions. The central limb extends along a central limb axis. The primary winding is wound on the central limb and consists of a plurality of winding coils each having a coil plane orthogonal to the central limb axis. The primary winding surrounds the central limb and has a central aperture defined by the central limb.

[065] The example secondary core is a C-shaped magnetic core and the secondary winding is wound on a middle limb of the C-shaped magnetic core. The C-shaped magnetic core is integrally formed of a magnetic material of high magnetic permeability, has a top limb, a bottom limb, and a middle limb. The middle limb extends along a middle limb axis. The top limb extends from a first (say, top) longitudinal end of the middle limb and projects orthogonally away from the middle limb. The bottom limb extends from a second (say, bottom) longitudinal end of the middle limb and projects orthogonally away from the middle limb and extends in the same direction as the top limb. The top limb and the bottom limb are parallel, spaced apart and cooperate to define an inter-limb space which is to function as a secondary winding receptacle.

[066] The secondary core has a width and the width of the primary core is comparable to or matched with the width of the secondary core. In example embodiments, the secondary core has a uniform width along a C-shape path defining the C-shape of the secondary core. The height of the primary core, which is measured along the axial direction of the primary core as defined by the central limb axis, is comparable to or matched with the longitudinal clearance of the secondary winding receptacle. The height of the primary core and the longitudinal clearance of the secondary winding receptacle are arranged to be matched so that the primary and secondary cores are in closely-fitted abutment contact when they are brought into formation of the closed magnetic circuit for power transfer. The width of the primary core and the width of the secondary core or the secondary winding receptacle are matched to facilitate maximum power transfer efficiency and so that a complete magnetic core of the power transfer apparatus has side flush side surfaces. The example complete magnetic core has an O-shape with right angle corners. The power transfer apparatus is an electrical power transfer apparatus resembling an electrical power transformer, but having a secondary portion which is detachable from the primary portion or vice versa. The complete magnetic core comprises a top limb, a bottom limb, a first side limb and a second side limb. The first side limb and the second side limb are parallel and spaced apart, with the central limb of the primary core forming the first side limb and the middle limb of the secondary core forming the second side limb.

[067] During charging operations, the primary portion is moved into proximity of the secondary portion, and more specifically, moved into channel defined by a pair of parallel limbs on longitudinal ends of the middle limb of the secondary core to facilitate wireless power charging. During charging operations, the primary and secondary portions may be fastened using a clutch member. After charging is complete, the clutch member is removed and the primary portion is detached and moved away from the secondary portion. The secondary portion or at least the middle limb portion of the secondary portion is sealed to ensure water-tightness so that no water leaks into the water tight equipment compartment when the vessel is on water.

[068] The magnetic circuit formed by the primary portion and the secondary portion has a magnetic field density B _m and a magnetic flux f, and a peak magnetic flux f _, where

[069] Where the magnetic circuit uses a ferrite core, the magnetic flux should be designed to be less than 0.35 Tesla.

[070] Where the supply power is in the form of a square wave train, the input voltage V _in = root mean square voltage V _rms , and

[071] Where A _e is the effective area of the magnetic core, N _p is the number of the turns of the spiral coils refereed to the primary side, is the operational frequency of the power transfer current or voltage which is high frequency in the range of 20kHz to 200kHz. The input voltage is the transfer voltage and it is derived from the front-end power processing unit.

[072] Operation flows of the vessel are summarized in Figure 5.

[073] While the disclosure has been made with reference to example embodiments, the embodiments are non-restrictive examples which should not be used to restrict scope of the disclosure.