EP4691896A1

EP4691896A1 - Electric hydrofoil watercraft

Info

Publication number: EP4691896A1
Application number: EP24472014.0A
Authority: EP
Inventors: Ivaylo Emilov Velev
Original assignee: Sifly Ai Ltd
Current assignee: Sifly Ai Ltd
Priority date: 2024-08-09
Filing date: 2024-08-09
Publication date: 2026-02-11
Also published as: US20260042514A1

Abstract

The electric hydrofoil watercraft according to the invention has a thermally insulated mast, thermal insulation and vibration isolation are provided between the mast (2) and the above-water platform (1) by placing an insulating element (10) between them. This increases the life of the hydrofoil and improves user experience.

Description

TECHNICAL FIELD

The invention relates to an electric hydrofoil watercraft, which is used in the field of water sports.

PRIOR ART

The electric hydrofoil is a complex mechanical product that combines several products in one. At its core, it is a surfboard, which is an above-water platform under which a hydrofoil, connected to a power source and to an electric motor connected to a controller, is mounted. The power source is most often a rechargeable lithium-ion battery containing battery control system that takes care of the operation of the battery in safe conditions. The electric motor is most often brushless. The controller usually consists of main system control unit connected to electronic motor speed controller, sensor unit, and control module by which the surfer commands the motor power and adjusts its speed. The electronic speed controller of the electric motor ensures the conversion of direct current from the battery into alternating current flowing through the three phases of the electric motor.
The hydrofoil is an assembly of underwater wings mounted on an underwater arrow-shaped body, which is attached to the above-water platform by means of a streamlined metal mast, usually made of aluminum, which connects the above-water platform to the hydrofoil's fuselage.
Unlike the sailing varieties of surfing, the electric hydrofoil is powered by electric motor mounted to the fuselage of the hydrofoil or it is attached to the mast. The power source is a battery that can be housed in or attached to the above-water platform or mast. The control of the power of the electric motor and respectively the speed of movement is usually achieved by a wired or wireless remote control by which the surfer issues commands.
An important issue for the transition of electric hydrofoils into a mass product is the increase of reliability of the device. One of the frequently failing elements of the hydrofoil is the electronic speed controller, which is located in the above-water platform, or in a component mounted to it, the electronic speed controller provides the connection of a source of electricity with the electric motor of the hydrofoil. This controller is housed in waterproof volumes containing at least one metal wall acting as a radiator, which is in metal-to-metal contact with the aluminum mast, which is most often used to attach the fuselage with the hydrofoil wings to the board. The mast, in turn, is in constant contact with the body of water in which the sport is practiced. This creates conditions for rapid wear and aging of electronics especially, but not only, in northern locations with cold waters. The high temperature difference between the metal skeleton (the aluminum profile, the fuselage and the above-water platform or part mounted thereto) and the electronic speed controller that is directly or indirectly mounted thereto results in a significant constant temperature stress on the electronics. The temperature in the mentioned locations can reach values of 2 degrees Celsius, while the electronics heat up to temperatures of 80 degrees Celsius. Depending on system load, electronics are subject to frequent, rapid, and large temperature changes in this range. This strong contrast results in significant temperature stress, which can cause frequent thermal expansion and contraction of circuit boards, weakening of electronic component solders, and faster wear of the electronic components themselves. In addition, large temperature differences can also lead to unstable operation of integrated circuits in electronics, which often have a preferred temperature operating range. The results of these operating conditions of the control, regulation and communication electronics are:

Unstable operation of the controller during movement, which is a prerequisite for falls and injuries;
Rapid wear and fault of electronics, requiring service or replacement.

A further disadvantage of prior art electric hydrofoil watercraft is the presence of high noise and vibration which is transmitted from the electric motor to the entire system and which leads to several significant problems. First, the quality of the user experience while using the hydrofoil is reduced. The above-water platform, which is rigidly connected to the mast of the hydrofoil, vibrates and amplifies the audible noises produced by the electric motor, thus worsening the sensation of flying over water. Second, in addition to being an inconvenience to the user, vibrations also pose a risk to the hydrofoil's electronics and battery. They can be the cause for destruction of solders of electronic components, damage to electronic components, disturbances in the operation of integrated circuits of electronics, as well as damage to the battery pack - peeling off of the metal busbars welded to the cells.
An electric hydrofoil watercraft is known from the prior art, described in patent application EP3642106A1 , which comprises a mast connecting an above-water platform to a fuselage and hydrofoils. An electric motor is connected to the lower end of the mast. The mast is integrated with a module placed at its top, having a waterproof housing, which houses control, regulation and communication electronics, and with this module, the mast is bolted to the above-water platform. The module connects to a power source located in the above-water platform and provides a thermal bridge between the control, regulation and communication electronics in it and the mast, which in turn is in constant contact with the water during the use of the hydrofoil. This design has the aforementioned prior art disadvantages, namely that a thermal bridge is provided to the hydrofoil's electronics, and that the vibrations from the electric motor are transmitted to the rest of the hydrofoil, including electronics, and these circumstances lead to already mentioned risks for the hydrofoil, and its faster damage.

SUMMARY OF THE INVENTION

The object of the invention is to create an electric hydrofoil watercraft that has an increased service life and to improve the user experience with electric hydrofoils.
This object is achieved by creating an electric hydrofoil watercraft, comprising:

above-water platform,
hydrofoil comprising a fuselage with a front wing and at least one stabilizer,
mast connecting the above-water platform to the fuselage of the hydrofoil,
underwater propulsion means for creating horizontal thrust having at least one electric motor connected by wire to a source of electricity in the above-water platform by means of electrical cables located inside the mast, which underwater propulsion means is mounted to the hydrofoil or to the mast,
electronic module in which the control, regulation and/or communication electronics of the electric watercraft are located in a waterproof housing, the electronic module has electrical connectors for connecting to the source of electricity in the above-water platform, wherein the mast is mounted to the waterproof housing of the electronic module, which in turn is mounted to the above-water platform.

According to the invention, the control, regulation and/or communication electronics in the electronic module are thermally isolated from the mast.
The housing of the electronic module can be made of a thermally conductive material.
Preferably, the thermal insulation comprises an insulating element made of thermally insulating material, which is placed between the mast and the housing of the electronic module.
Preferably, the insulating element has a shape corresponding to the cross-sectional profile of the mast and it has openings for passage of the electrical cables from the mast.
Preferably, the openings of the insulating element coincide with internal channels in the mast's profile in which the electrical cables are located.
Preferably, the material from which the insulating element is made is additionally a vibration-isolating material. Even more preferably, the material from which the insulating element is made is additionally a noise-insulating material.
Exemplary materials that can be used to make the insulating element are rubber, ceramic material, high density polyurethane, or composite material of carbon, fiberglass, and Kevlar.
In one embodiment of the invention, the mast is fixed in a socket of the electronic module, and the insulating element has an additional peripheral insulating collar covering the contact surface between the side wall of the mast and the socket of the electronic module.
In one embodiment of the invention, the mast is provided with a detachable or integral coupling element, by which the mast is attached to the electronic module, the insulating element is placed between the coupling element and the housing of the electronic module and/or between the mast and the coupling element.
In one embodiment of the invention, the mast is attached to the housing of the electronic module by screws passing through through holes in the housing of the electronic module and screwed into threaded internal longitudinal channels of the mast, and insulating washers are placed between the housing of the electronic module and the heads of the screws. Preferably, insulating sleeves through which the screws pass are provided in the through holes of the housing of the electronic module through which the screws pass.
In one embodiment of the invention, a layer of heat-insulating resin is applied to the mast at least partially in its area of contact with the housing of the electronic module.
In one embodiment of the invention, the electronic module is configured to be detachably connected to the above-water platform.
Advantages of the electric watercraft according to the invention are that it increases the safety of users of electric surfboards, as well as it extends the life of electric hydrofoils and their components, due to the interruption or limitation of the thermal bridge and transmission of vibrations between the mast and the above-water platform where the control, regulation and communication electronics are located. Additionally, user experience is improved due to less vibration and noise.

BRIEF DESCRIPTION OF THE DRAWINGS

Further in the description, the watercraft, which is the object of the invention, is explained with a preferred embodiment, given as a non-limiting the scope of the invention example, with reference to the attached figures, where:

Figure 1 is side view of an electric hydrofoil with its main components.
Figure 2 is partial exploded perspective view of the electric hydrofoil watercraft according to a preferred embodiment of the invention, showing the mast, the insulating element and the electronic module.

EXAMPLARY EMBODIMENTS AND OPERATION OF THE INVENTION

The terms "over", "under", "top", "bottom", "front", "rear" in this specification and in the claims refer to the relative arrangement of the structural elements as shown in the figures and in the usual operating position of the device.
The electric hydrofoil watercraft with a thermally insulated mast, according to a preferred embodiment of the invention shown in the figures, comprises:

above-water platform 1,
hydrofoil comprising a fuselage 5 with a front wing 7 and at least one stabilizer 8,
mast 2 connecting the above-water platform 1 to the fuselage 5 of the hydrofoil, which mast 2 has internal longitudinal passage channels for the passage of electrical cables,
underwater propulsion means 6 for creating horizontal thrust having at least one electric motor connected by wire to a source of electricity in the above-water platform 1 by the electric cables located inside the mast 2, which underwater propulsion means 6 is mounted to the hydrofoil or to the mast,
electronic module 9, in which waterproof housing the control, regulation and/or communication electronics of the electric watercraft are located, the electronic module 9 has electrical connectors for connecting to the source of electricity in the above-water platform 1. The mast 2 is mounted to the waterproof housing of the electronic module 9, which in turn is mounted to the above-water platform.

Part of the control, regulation and/or communication electronics can comprise an electronic hydrofoil speed controller, which is coupled to the electric motor.
The connection between the mast 2 and the above-water platform 1 is hermetic to protect the electronics or cables from getting wet, and waterproof seals are provided for this purpose.
The hydrofoil elements are made of the usual suitable materials known in the art. The stabilizer 8, the front wing 7 and, if there is an additional stabilizer 4 with its corresponding holder 3, for example, can be made of composite materials such as fiberglass and carbon, plastic or aluminum, which can be used both alone or in combination with each other,. The above-water platform 1 can be made of expanded polystyrene (EPS), expanded polypropylene (EPP), impregnated plywood, etc. The mast 2 can be made of aluminum. The housing of the electronic module 9 is made of heat-conducting material. Also, the listed materials can be in combination with a carbon coating applied by a corresponding known method.
In order to limit the temperature stress on the electronics created by the large temperature amplitudes, it is necessary to break or limit the thermal bridge between the control, regulation and communication electronics (electronic speed controller) and water during the use of the electronic watercraft when there is no direct contact of the electronic module 9 with water, which occurs only during the launch and landing of the electric watercraft relative to the water. This can be achieved by the use of an element with a heat-insulating material between the mast's profile and the subsequent parts of the hydrofoil device arranged in the above-water platform 1. The mast 2, usually made of aluminum, has the role of a large-area radiator, which always is submerged in the water during the use of the hydrofoil. Accordingly, by thermally insulating its upper end, the ability of heat transfer to the mast is eliminated and the harmful effect of temperature stress on the electronics above it is stopped.
In order to reduce the vibrations from the motor, a solution is needed, which can be applied either when the electric motor is embedded in the hydrofoil, or at the border of the first rigidly connected to it part and the next component. In most cases, the electric motor is attached to the fuselage 5 or to the mast 2. A solution for both cases is to provide a pad of material with vibration and noise isolation at the top of the profile of the mast 2 before connecting it to the above-water platform 1. This provides a break in the path of vibration for all industry known methods of mounting an electric motor to an electric hydrofoil.
In the embodiment shown in figure 2, an insulating element 10 made of heat-insulating material is arranged between the mast 2 and the housing of the electronic module 9 in order to interrupt the temperature transfer from the housing of the electronic module 9 to the mast 2. Figure 2 shows only the bottom part of the housing of the electronic module, to which the mast 2 is mounted. Preferably, the shape of the insulating element 10 corresponds to the cross-sectional profile of the mast 2, and there are openings for the passage of electrical cables from the mast 2, as shown in the figure.
The material from which the insulating element 10 is made must be hard enough to withstand the mechanical stresses during the use of the hydrofoil, and preferably have noise dampening and vibration dampening functions, while also being a good thermal insulator. Such materials can be, for example, rubber, ceramic material, high density polyurethane, or composite material of carbon, fiberglass, and Kevlar, which can be used both alone or in combination with each other, or any other suitable material that breaks the thermal bridge between its adjacent parts and has suitable elastic properties, which absorb the vibrations from the electric motor and do not transfer them to the above-water platform 1, where the electronics and battery are housed.
It is possible that the insulating element 10 is placed directly between the mast 2 and the housing of the electronic module 9, or alternatively there is an additional mounting piece between the mast 2 and the housing of the electronic module 9, the insulating element being placed on one side of the piece. In the case when the insulating element 10 is placed directly between the mast 2 and the housing of the electronic module 9, the insulating element must lie tightly between them, and accordingly the openings for passage of the electric cables must coincide with the channels of the mast 2. In the case of presence of an additional piece between the mast 2 and the housing of the electronic module 9, it can be a coupling element by which the mast 2 is fixed to the housing of the electronic module 9, and the insulating element 10 can be placed between the coupling element and the housing of the electronic module 9 or between the coupling element and the mast 2, or there can be two insulating elements, on both sides of the coupling element, and in all three cases, the shape of the insulating element must be such that it covers the area of contact between its adjacent parts. It is also possible to use additional pieces that constructively support the attachment of the mast 2 to the above-water platform 1, and accordingly the place of attachment of the mast 2 to the above-water platform 1 can coincide with these pieces. These are, for example, mounting plates or such that modify the profile of the mast 2 at the mounting, to the above-water platform 1, end.
It is also possible to use such additional pieces as, for example, pads that allow changing the shape of the assembled configuration. In each of these embodiments, an additional insulating element is placed either between the corresponding additional piece and the mast 2, or between the corresponding additional piece and the housing of the electronic module 9, or there are two insulating elements. In these cases, the shape of said insulating element must be such that it covers the area of contact between its adjacent pieces.
In the case when at the end of the mast 2 on the side facing the above-water platform 1 there is a coupling element for mechanical attachment to the housing of the electronic module of the above-water platform 1, the coupling element of the mast 2 can be integrally connected to it or detachably connected to it. In the embodiment with integral connection, the insulating element 10 is placed between the coupling element of the mast 2 and the housing of the electronic module 9. In the case when the mast 2 is detachably connected to the coupling element, the insulating element 10 can be placed both between the coupling element of the mast 2 and the housing of the electronic element 9, as well as between the mast 2 and the coupling element.
The mast 2 can be fixed in a socket of the housing of the electronic module 9, in which case the insulating element 10 has on its periphery an additional insulating collar covering the contact surface between the side wall of the mast 2 and the inner wall of the socket of the housing of the electronic module 9.
A hermetic connection is provided between the mast 2 and the above-water platform 1 by placing waterproof seals for the cables providing power and communication to the underwater propulsion means.
The mast 2 or additional piece of the mast 2, for example a coupling element, can be attached to the housing of the electronic module 9 by various types of fastening means, for example, by screwing screws 11 that pass through the housing of the electronic module 9 and are screwed in a thread in internal longitudinal passage channels for fixing the mast 2. In order to ensure thermal insulation, insulating washers 12 for the screws 11 are provided on the upper side of the housing of the electronic module 9, wherein the heads of the screws remain isolated from the housing of the electronic module 9 by the insulating washers 12, as shown in figure 2. The insulating washers 12, like the insulating element 10, are made of a heat insulating material, and preferably, the material is also a vibration and noise insulating material. In addition, insulating sleeves can be provided in the through holes of the housing of the electronic module 9, through which the screws 11 pass, in order to completely isolate the screws 11 from the housing of the electronic module 9. The insulating sleeves are also made of heat insulating material, and preferably, the material is also a vibration and noise insulating material.
The electronic module 9 can be configured to be detachably connected to the above-water platform 1 by means of fixing elements such as screws or other means known in the art.
A layer of thermal insulating resin can be applied to the mast 2 at least partially in its area of contact with the housing of the electronic module 9. This layer of thermal insulating resin can be used to supplement the thermal insulation in case the insulating element 10 does not completely cover the area of contact between the mast 2 and the housing of the electronic module 9, in which case the thermal insulating resin layer is applied to the region of the contact zone where the insulating element 10 is not present. The same principle of applying the thermal insulating resin layer can be used between the mast 2 and an additional piece, for example a coupling element, or between the housing of the electronic module 9 and an additional piece of the mast 2, for example a coupling element.
It will be clear to those skilled in the art that various modifications of the electric hydrofoil with thermally insulated mast are possible, which are also within the scope of the invention as defined in the appended claims. All parts of the electric hydrofoil can be replaced with technically equivalent elements.
The reference numbers of the technical features are included in the claims solely for the purpose of increasing the comprehensibility of the claims and, therefore, these reference numbers do not have any limiting effect on the interpretation of the elements indicated by these reference numbers.

Claims

Electric hydrofoil watercraft comprising:
- an above-water platform (1),

- a hydrofoil comprising a fuselage (5) with a front wing (7) and at least one stabilizer (8),

- a mast (2) connecting the above-water platform (1) to the fuselage (5) of the hydrofoil,

- an underwater propulsion means (6) for creating horizontal thrust having at least one electric motor, which underwater propulsion means (6) is connected by wire to a source of electricity in the above-water platform (1) by electrical cables located inside the mast (2), which underwater propulsion means (6) is mounted to the hydrofoil or to the mast (2),

- an electronic module (9) having in a waterproof housing in which the control, regulation and/or communication electronics of the electric watercraft are located, the electronic module (9) has electrical connectors for connecting to the source of electricity in the above-water platform (1), wherein the mast (2) is mounted to the waterproof housing of the electronic module (9), which in turn is mounted to the above-water platform (1),
characterized in that
the control, regulation and/or communication electronics in the electronic module (9) are thermally isolated from the mast (2).
Electric hydrofoil watercraft according to claim 1, characterized in that the housing of the electronic module (9) is made of thermally conducting material, the thermal insulation comprises an insulating element (10) made of thermally insulating material, which is placed between the mast (2) and the housing of the electronic module (9).
Electric hydrofoil watercraft according to claim 2, characterized in that the insulating element (10) has a shape corresponding to the cross-sectional profile of the mast (2), and it has openings for passage of the electrical cables from the mast (2).
Electric hydrofoil watercraft according to any of the preceding claims, characterized in that the material from which the insulating element (10) is made is also a vibration-isolating material.
Electric hydrofoil watercraft according to any of the preceding claims, characterized in that the material from which the insulating element (10) is made is also a noise-insulating material.
Electric hydrofoil watercraft according to any of the preceding claims, characterized in that the material of which the insulating element (10) is made is selected from: rubber, ceramic material, high density polyurethane, or composite material of carbon, fiberglass, and Kevlar.
Electric hydrofoil watercraft according to any of the preceding claims, characterized in that the mast (2) is fixed in a socket in the housing of the electronic module (9) and the insulating element (10) has an additional insulating collar extending along its periphery and covering the contact surface between the side wall of the mast (2) and the socket in the housing of the electronic module (9).
Electric hydrofoil watercraft according to any of the preceding claims, characterized in that the mast (2) is provided with a detachable or integral coupling element, by which the mast (2) is attached to the electronic module (9), the insulating element (10) is placed between the coupling element and the housing of the electronic module (9) and/or between the mast (2) and the coupling element.
Electric hydrofoil watercraft according to any of the preceding claims, characterized in that the mast (2) is attached to the housing of the electronic module (9) by means of screws (11) passing through through holes in the housing of the electronic module (9) and screwed into threaded internal longitudinal channels of the mast (2), wherein insulating washers (12) are placed between the housing of the electronic module (9) and the heads of the screws.
Electric hydrofoil watercraft according to claim 9, characterized in that insulating sleeves through which the screws (11) pass are provided in the through holes in the housing of the electronic module (9) through which the screws (11) pass.
Electric hydrofoil watercraft according to any of the preceding claims, characterized in that a layer of heat-insulating resin is applied to the mast (2) at least partially in its area of contact with the housing of the electronic module (9).
Electric hydrofoil watercraft according to any of the preceding claims, characterized in that the electronic module is configured to be detachably connected to the above-water platform (1).