Hydrofoil watercraft

Abstract

Disclosed is a fuselage assembly (100) configured to be attached to a mast assembly (50) of a powered hydrofoil watercraft (1). The fuselage assembly (100) comprises a mast assembly fixation section (106) and an outer housing portion (170) which accommodates, in particular surrounds or encases, a propulsion device (200), in particular an impeller (201), and which outer housing portion (170) at least partially limits an outer dimension of a flow channel (161) through which water is transported during operation of the hydrofoil watercraft (1). The outer housing portion (170) comprises an attachment portion (310) on which a tail unit (300), in particular 10 comprising a stabilizing member (301) such as a stabilizing wing (302), is formed or attachable thereto. In addition or alternatively, the propulsion device (200) may be accommodated in the outer housing portion (170) such that a user is prevented from touching the propulsion device (200).

1 . A fuselage assembly ( 100 ) configured to be attached to a mast assembly ( 50 ) of a powered hydrofoil watercraft ( 1 ), wherein said fuselage assembly ( 100 ) comprises a mast assembly fixation section ( 106 ) and an outer housing portion ( 170 ) which accommodates a propulsion device ( 200 ), and which outer housing portion ( 170 ) at least partially limits an outer dimension of a flow channel ( 161 ) through which water is transported during operation of said hydrofoil watercraft ( 1 ), wherein said flow channel ( 161 ) is formed such that its cross sectional area is reduced towards an outlet side of said flow channel ( 161 ), and wherein (I) said outer housing portion ( 170 ) comprises an attachment portion ( 310 ) on which a tail unit ( 300 ), is formed or attachable thereto and/or wherein (II) said propulsion device ( 200 ) is accommodated in said outer housing portion ( 170 ) such that a user is prevented from touching said propulsion device ( 200 ). 
     
     
         2 . The fuselage assembly ( 100 ) according to  claim 1 , wherein said outer housing portion ( 170 ) is configured for detachably fixing said tail unit ( 300 ) to the same, or wherein alternatively said outer housing portion ( 170 ) and said tail unit ( 300 ) are integrally formed. 
     
     
         3 . The fuselage assembly ( 100 ) according to  claim 1 , further comprising a wing attachment section ( 105 ) and a front wing ( 112 ) attached to said wing attachment section ( 105 ), wherein said wing attachment section ( 105 ) is provided at a front portion ( 101 ) of said fuselage assembly ( 100 ) and is configured to detachably mount said front wing ( 112 ). 
     
     
         4 . The fuselage assembly ( 100 ) according to  claim 3 , wherein said tail unit ( 300 ) and/or said front wing ( 112 ) mounted on said fuselage assembly ( 100 ) are configured to be transferable between a use state in which said tail unit ( 300 ) is able to exert a stabilizing function and/or said front wing ( 112 ) is positioned to generate a lifting force, and a stowing state, wherein in said stowing state a mast assembly profile and a profile of said tail unit ( 300 ) and/or of said front wing ( 112 ) are arranged substantially in one plane, wherein said tail unit ( 300 ) and/or said front wing ( 112 ) are rotatable about a rotational axis, for example a longitudinal middle axis (A 1 ) of said fuselage assembly ( 110 ) or an axis parallel to said longitudinal middle axis (A 1 ), such that said tail unit ( 300 ) and/or said front wing ( 112 ) are rotatable about 90° between said use state and said stowing state. 
     
     
         5 . The fuselage assembly ( 100 ) according to  claim 1 , wherein said outer housing portion ( 170 ) comprises an upstream end portion ( 177 ) defining an inlet opening ( 178 ) and wherein said housing portion ( 170 ) comprises a downstream end portion ( 179 ) which comprises a nozzle section ( 172 ) with an outlet opening ( 191 ), wherein a cross sectional area of said inlet opening ( 178 ) is larger than a cross sectional area of said outlet opening ( 191 ), wherein said cross sectional area at said outlet opening ( 191 ) is at least 5% smaller than said cross sectional opening of said inlet opening ( 178 ) and wherein said cross sectional area at said outlet opening ( 191 ) is 90% to 80% the size of said cross sectional area of said inlet opening ( 178 ), wherein in addition or alternatively said nozzle section ( 172 ) is detachably configured and is made from a plastics material. 
     
     
         6 . The fuselage assembly ( 100 ) according to  claim 5 , wherein said outer housing portion ( 170 ) and said propulsion device ( 200 ) accommodated therein are configured and arranged with respect to each other such that it is not possible to reach said propulsion device ( 200 ) with a human extremity, wherein a length of said outer housing portion ( 170 ) and/or the size of said inlet opening ( 178 ) and/or the size of said outlet opening ( 191 ) and/or the position of said propulsion device ( 200 ) in said outer housing portion ( 170 ) and/or a dimension of said flow channel ( 161 ) are adjusted and/or positioned such that said propulsion device ( 200 ) cannot be reached by means of a human extremity through said inlet opening ( 178 ) and said outlet opening ( 191 ) and/or wherein a safety member is provided which blocks an access for human extremities, wherein said safety member is provided downstream or upstream of said propulsion device ( 200 ) and is a stator ( 174 ), and wherein in addition or alternatively said length of said flow channel ( 161 ) between said inlet opening ( 178 ) and said propulsion device ( 200 ) is at least 30 mm and/or wherein in addition or alternatively a height or width of said inlet opening ( 178 ) is equal to or smaller than 30 mm, and/or wherein in addition or alternatively a length of said stator ( 174 ) in flow direction of said flow channel ( 161 ) is equal to or larger than 5 mm and/or wherein in addition or alternatively said size of said outlet opening is equal to or smaller than 30 mm. 
     
     
         7 . The fuselage assembly ( 100 ) according to  claim 5 , wherein said flow channel ( 161 ) is formed between said outer housing portion ( 170 ) and an inner housing portion ( 180 ) which is suitable for supporting said propulsion device ( 200 ), and/or wherein said flow channel ( 161 ) is formed as a ring channel extending about said longitudinal middle axis (A 1 ) and circumferentially surrounding said inner housing portion ( 180 ) with its cross section in a direction perpendicular to said longitudinal middle axis (A 1 ) defining a ring and/or wherein said inlet opening ( 178 ) is formed between said upstream end portion ( 177 ) and an outer surface section ( 181 ) of said inner housing portion ( 180 ), and/or wherein said inlet opening ( 178 ) is formed as an annular inlet opening or an elliptical inlet opening, and/or wherein said flow channel ( 161 ) is configured such that an inlet angle ( 184 ) smaller than 20° is realized at said inlet opening ( 178 ). 
     
     
         8 . The fuselage assembly ( 100 ) according to  claim 5 , wherein said outer housing portion ( 170 ) is connected to said inner housing portion ( 180 ) via circumferentially distributed struts ( 190 ) arranged around said longitudinal middle axis (A 1 ) so that said outer housing portion ( 170 ) is held cantilevered on said inner housing portion ( 180 ), said struts ( 190 ) at least partially extending in the longitudinal direction of said fuselage assembly ( 110 ) and bridging said inlet opening ( 178 ), wherein said struts ( 190 ) are aerodynamically formed so as to reduce turbulences and comprise a wing shape. 
     
     
         9 . The fuselage assembly ( 100 ) according to  claim 8 , wherein at least a portion of said outer housing portion ( 170 ), and said rear end portion ( 183 ) of said inner housing portion ( 180 ) are fixedly coupled to each other, thereby defining a propulsion section ( 160 ) of said fuselage assembly ( 100 ), and wherein in addition or alternatively said propulsion section ( 160 ) is detachably coupled to a front portion ( 101 ) of said fuselage assembly ( 100 ). 
     
     
         10 . The fuselage assembly ( 100 ) according to  claim 5 , further comprising a flap mechanism for selectively opening and closing said inlet opening ( 178 ), wherein said flap mechanism is designed such that a negative pressure generated by said propulsion device ( 200 ) automatically actuates said flap mechanism, wherein said flap mechanism comprises one or more flaps which are pre-biased in the closing direction, and which flaps are moved into an opened position against the pre-biasing force when there is a corresponding negative pressure and are automatically moved into a closed position driven by the pre-biasing force when there is no sufficiently large negative pressure. 
     
     
         11 . The fuselage assembly ( 100 ) according to  claim 1 , further comprising a front portion ( 101 ) adapted to sealingly receive an electric motor, wherein said electric motor is thermally coupled to a casing ( 110 ) of said front portion ( 101 ) for cooling purposes, wherein optionally a motor housing of said electric motor also forms a part of said casing ( 110 ) of said front portion ( 101 ) in such a manner that said motor housing gets in contact with water on its outer side, such that a direct cooling of said electric motor is possible. 
     
     
         12 . The fuselage assembly ( 100 ) according to  claim 11 , wherein said front portion ( 101 ) is further adapted to receive a controller couplable to said electric motor, said controller being thermally coupled to said casing ( 110 ) of said front portion ( 101 ) for cooling purposes, wherein said front portion ( 101 ) optionally comprises a controller receiving space separated and sealed from an electric motor receiving space. 
     
     
         13 . The fuselage assembly ( 100 ) according to  claim 1 , wherein said mast assembly fixation section ( 106 ) bels provided on a top side of said fuselage assembly ( 110 ), wherein in addition or alternatively said mast assembly fixation section ( 106 ) comprises a mounting recess ( 107 ) in which a fuselage assembly fixation portion ( 54 ) of said mast assembly ( 50 ) can be inserted and locked, wherein said mast assembly fixation section ( 106 ) is designed for a positive locking or an integral connection of said mast assembly ( 50 ) with said mast assembly fixation section ( 106 ). 
     
     
         14 . An integrated propulsion unit for a powered hydrofoil watercraft, comprising the fuselage assembly ( 100 ) according to  claim 1 , an electric motor provided in said fuselage assembly ( 110 ) and a propulsion device ( 200 ) provided in said outer housing portion ( 170 ), said electric motor being operatively connected to said propulsion device ( 200 ) by means of a drive shaft ( 203 ) accommodated in said inner housing portion ( 180 ), or wherein said propulsion device ( 200 ) is directly coupled to an output shaft of said electric motor. 
     
     
         15 . A hydrofoil watercraft ( 1 ), comprising a board assembly ( 10 ), a mast assembly ( 50 ) coupled to a lower portion ( 12 ) of said board assembly ( 10 ), and the integrated propulsion unit according to  claim 14 , wherein a front wing ( 112 ) and the tail unit ( 300 ) are attached to said fuselage assembly ( 100 ) of said integrated propulsion unit. 
     
     
         16 . The fuselage assembly of  claim 2 , wherein said detachable fixation is achieved by means of positive locking, and wherein said outer housing portion ( 170 ) comprises an attachment portion ( 310 ) for detachably attaching said tail unit ( 300 ). 
     
     
         17 . The fuselage assembly of  claim 16 , wherein the positive locking is a latching plug and socket connection having a dovetail geometry or being realized by pins. 
     
     
         18 . The fuselage assembly of  claim 16 , wherein the tail unit comprises an attachment flange having a threaded opening. 
     
     
         19 . The fuselage assembly of  claim 4 , wherein said wing attachment section ( 105 ) and/or said attachment portion ( 310 ) are individually rotatable about said rotational axis or wherein said mast assembly fixation section ( 106 ) is configured such that said fuselage assembly is rotatably coupled to said mast assembly ( 50 ). 
     
     
         20 . The fuselage assembly of  claim 1 , wherein the tail unit a stabilizing member ( 301 ) optionally wherein the stabilizing member is a stabilizing wing ( 302 ).