WO2023065018A1

WO2023065018A1 - Drive module for connecting a hydrofoil to a board

Info

Publication number: WO2023065018A1
Application number: PCT/CA2022/051528
Authority: WO
Inventors: Thomas Hewitt
Original assignee: Netzero Construction
Priority date: 2021-10-21
Filing date: 2022-10-17
Publication date: 2023-04-27

Abstract

A drive module for removable attachment to a flotation board and a hydrofoil. The drive module includes a watertight casing that houses a battery and a motor controller. The casing has watertight passageways through the casing to receive fasteners for removable attachment of the drive module to fastener receiving means of the flotation board. The drive module also includes a propulsion system that comprises a strut and a motor with a propeller. The upper end of the strut is fixedly coupled to the casing. The lower end of the strut being configured to be removably coupled to a hydrofoil. The drive module forming an integral unit.

Description

DRIVE MODULE FOR CONNECTING A HYDROFOIL TO A BOARD

FIELD OF THE INVENTION

[1] The present invention pertains to the field of electrically powered watercraft with hydrofoil, and in particular to a drive module that is removably attached to a flotation board and to a hydrofoil to form an electrically powered watercraft with hydrofoil.

BACKGROUND

[2] An efoil (also called an electric foil, an electric hydrofoil and a powered hydrofoils) is a personal watercraft that generally includes a custom designed flotation board which houses a rechargeable battery and a motor controller, a strut with an electric propeller system couple to the board, a hydrofoil (a wing like structure) coupled to the strut and a wireless hand controller with throttle control. The hydrofoil and an electric propeller system extend below the board into the water during operation. As the efoil gains speed by activation of the throttle control, the hydrofoil lifts the board above the surface of the water, decreasing drag for the efoil and allowing greater speeds.

[3] Efoils are becoming increasingly popular especially with water sports/activities enthusiasts such windsurfers, surfers and kiteboarders. Efoils are fairly silent, emission-free, do not create a wake, are fairly easy to ride and do not rely entirely on weather conditions to operate making efoils a nice complement to many water sport enthusiasts.

[4] At this time, the costs of efoils are fairly high. The typical system can range from $5,000 to $15,000. Part of the reason for the high costs is that the current efoil systems include a specially designed flotation board which includes an integrated compartment or well in the board to hold the power supply system.

[5] In addition to the high costs of the systems, purchasers must select a single size and shape of board for their efoil. Given that the current efoil systems have a specific board sizing and style, they cannot be easily be shared with riders of different weights (larger volumes of boards may be needed for a heavier rider) or different level of experience (a bigger board will generally be more stable board whereas a smaller board will be more maneuverable). Moreover, a rider wishing to practice different sports/activities (windsurf, surf, wakeboard, paddle surf SUPs, touring SUPs) which would optimally require different styles and sizes of boards will need to select an efoil system with a single size and shape of board therefore sacrificing the ideal board specifications for a given sport/activity.

[6] There exist hundreds of types, models and sizes of “off the shelf’ floating boards (windsurf, surf, wakeboard, paddle surf SUPs, touring SUPs, longboard, fun board, hybrid, short board, fish, gun, twin tip) in the marketplace. Some sport enthusiast may already own multiple types and sizes of floating boards to practice non-efoil sports/activities. Hydrofoils are also designed in different shapes and sizes for different purposes and skill levels.

[7] There is need for an efoil drive module that can be removably coupled with a variety of “off the shelf’ floating boards with little or no modifications to the floating boards.

[8] There is need for an efoil drive module that can be removably coupled with a variety of types and sizes of foils.

[9] This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.

SUMMARY

[10] An object of embodiments of the present invention is to provide a drive module that can be removably attached to a flotation board and a hydrofoil to form a low-cost electrically powered watercraft with hydrofoil.

[11] In accordance with embodiments of the present invention, there is provided a drive module for removable attachment to a flotation board and a hydrofoil. The drive module includes a watertight casing that houses a battery and a motor controller. The casing has watertight passageways through the casing to receive fasteners for removable attachment of the drive module to fastener receiving means of the flotation board. The drive module also includes a propulsion system that comprises a strut and a motor with a propeller. The upper end of the strut is fixedly coupled to the casing. The lower end of the strut being configured to be removably coupled to a hydrofoil. The drive module forming an integral unit. [12] Embodiments have been described above in conjunctions with aspects of the present invention upon which they can be implemented. Those skilled in the art will appreciate that embodiments may be implemented in conjunction with the aspect with which they are described but may also be implemented with other embodiments of that aspect. When embodiments are mutually exclusive, or are otherwise incompatible with each other, it will be apparent to those skilled in the art. Some embodiments may be described in relation to one aspect, but may also be applicable to other aspects, as will be apparent to those of skill in the art.

BRIEF DESCRIPTION OF THE FIGURES

[13] Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings, in which:

[14] FIG. 1 provides a perspective view of a drive module attached to a flotation board and a hydrofoil forming an electrically powered watercraft with hydrofoil in accordance with an embodiment of the present invention;

[15] FIG. 2 provides a perspective view of a drive module attached to a hydrofoil in accordance with an embodiment of the present invention;

[16] FIG. 3 provides a provides a perspective view of a portion of the drive module with the casing cover separated from the casing body in accordance with an embodiment of the present invention;

[17] FIG. 4 provides a perspective view of a drive module without the casing cover on the casing body in accordance with an embodiment of the present invention;

[18] FIG. 5 provides a perspective view of a casing body with heat sink plate wherein the casing body is attached to the strut with its motor and propeller coupled to the without the casing cover on the casing body in accordance with an embodiment of the present invention; and

[19] FIG. 6 provides a bottom view of a drive module in accordance with an embodiment of the present invention. [20] It will be noted that throughout the appended drawings, like features are identified by like reference numerals.

DETAILED DESCRIPTION

[21] FIG. 1 illustrates an example of a drive module 1 in accordance with implementations of the present disclosure. The drive module 1 in FIG. 1 is shown coupled at its top end to a flotation board 2 and at its bottom end to a hydrofoil 3. The drive module 1 coupled with a flotation board 2 and a hydrofoil 3 forms an efoil.

[22] The drive module can be coupled to any type of flotation board 2 (windsurf, surf, wakeboard, paddle surf SUPs, touring SUPs, longboard, fun board, hybrid, short board, fish, gun, twin tip or other suitable boards) that are generally known to those of skill in the art. The board 2 are generally be made of foam, fiber-reinforced epoxy (using glass, carbon, or Kevlar fibers). The board 2 provides flotation for the rider and the drive module 1 and the hydrofoil 3 when they are coupled together to form an efoil. It also provided with a generally flat upper surface to allow a rider to he prone, sit, kneel or stand on it and an opposed bottom surface facing the water. The lower surface is generally almost flat.

[23] The board 2 preferably includes an integrated track mount. The standard track mount on flotation boards will generally consists of two polymer channels set 90mm apart. Alternatively, the board 2 can include a set of mounting holes in the board. The mounting holes are preferably non threaded and pierce the board from base to deck. The track mount or holes within the board are used to secure the drive unit 1 to the board 2.

[24] If the board 2 to be coupled to the drive unit 1 does not include a track mount or mounting holes, a FoilMount™ track system or similar after-market tracking systems can be installed on the base of the board 2. FoilMount™ is an adhesive hydrofoil track system that sticks to any flat board bottom surface. The FoilMount™ track system easily converts any surfboards, wakesurfers, and SUPs into kitefoils, Wingfoils, surf foil boards to be used with the drive unit 1.

[25] The hydrofoil 3 to be coupled with the drive unit 1 may be any hydrofoil combinations including but not limited to only the hydrofoil 3, more than one hydrofoil, and a hydrofoil coupled with a canard (two lifting wings system). The hydrofoil 3 is selected by a rider based on the rider’s weight, skill and the sport/activity with which the drive unit 1 will be used.

[26] The drive module 1 includes a power supply casing 5, a strut 10, a motor 15 and a propeller 20.

[27] Power supply casing 5 houses the battery or batteries (not shown), motor controller (not shown), a heat sink plate, a power button and a charging unit.

[28] The strut 10 has an upper end and a lower end. The upper end of the strut 10 is coupled to the bottom surface of the drive module in a variety of locations including but not limited to between the middle and rear sections and near the middle section. The inside of the strut 10 may be constructed so as to allow passage of electrical wires from the motor speed controller 45 to the electric motor 15. The primary function of the strut 10 is to rigidly connect the hydrofoil 3 at a fixed distance from the board 2. The strut 10 can have a plurality of dimensions including but not limited to approximately 30 cm to 160cm. The strut 10 may also be shaped differently than shown. The strut 10 is generally configured and oriented to reduce frictional drag with the water.

[29] As best seen at FIG. 2 and FIG. 6, the upper end of the strut 10 comprises a strut support 80. The strut 10 and strut support 80 are preferably made as a single unit made of extruded aluminum or aluminum alloy, thus reducing the number of parts to two. The strut support 80 includes a strut support sleeve 81 and an attachment plate 82.

[30] The strut support 80 receives an upper portion of the strut 10. The profile and crosssection of the strut support is slightly larger than the profile and cross-section of the strut 10 in order to receive the strut 10.

[31] The attachment plate 82 is generally flat and includes and extends outwardly from the top of the support sleeve 81. The attachment plate 82 includes a plurality of connector brackets or lateral flanges 83 with apertures 85.

[32] The apertures 85 are positioned to receive fasteners (not shown) that will fix the strut 10 with coupled motor 15 and propeller 20 to the casing 5 and ultimately to a tracking system in a board 2. [33] The strut 10 can extend below the motor 15 and can be detachably coupled to the hydrofoil 3.

[34] The motor 15 is an electric motor. In a preferred embodiment, the electric motor is a waterproof electric multiphase motor. The electric motor 15 is connected to the motor speed controller 45 using wires sized to carry the required voltage and current.

[35] A propeller 20 is coupled to the electric motor 15. An optional protective propeller guard (not shown) may surround the propeller 20.

[36] The electric motor 15 and coupled propeller 20 are preferably just above the hydrofoil 3.

[37] The motor 15 receives instructions from a user controller (not shown) that provides instructions to the motor control 45 to power the propeller 20 thereby serving as a propulsion system to operate the efoil. The motor 15 and couple propeller 20 transmit propulsion forces to the strut 10 and it transmits lift forces from the hydrofoil 2 to the strut 10.

[38] As shown in FIG. 3 the power supply casing 5 comprises a box like casing body 25 and a casing cover 30 which covers an opening 35 at the top of the casing body 25. The casing body having a base 26, a front wall 27, side walls 28 and a rear wall 29. The opening 35 houses the batteries 40 and the motor controller 45. In FIG. 3 the casing cover 30 is shown removed from the casing body 25. The casing body 25 and the casing cover 30 are preferably made of aluminum.

[39] The casing cover 30 seals casing body 25 so that water or other liquids will not enter opening 35 of the casing 5. The top edge of the sides of the casing body 25 comprises a peripheral flange 50 which is configured to mate with a peripheral sealing lip composed of a silicone rubber (not shown) of the casing cover 30 to create a hermetic and waterproof enclosure within the casing 5. The casing cover 30 includes a plurality of apertures 31 at the periphery of the casing cover 30 and proximate to pass though elongated hole 33. The walls (27, 28, 29) of the casing body 25 include matching apertures 32 to the apertures 31 of the casing cover 30. The casing cover 30 is affixed to the casing body 25 and further secured together via screws (not shown) through apertures 31 and 32. [40] The casing body 25 includes support members internal support members 37 which transfer the load from the hydrofoil 3 to the board 2. The support members 37 extend from the base 26 and are generally the same height as the walls (27, 28, 29) of the casing body 25. When the cover 30 is coupled to the casing body 25 a portion of the casing cover 30 will rest on top of the support members 37. The support members 37 are preferably made of aluminum. In an embodiment, the support members are integral with casing body 25. The support members 37 include elongated holes 34 which extend through the base 26.

[41] The casing cover 30 also includes apertures 33 which line up with each of the elongated holes 34 of the support members 37. Each aperture 33 has a corresponding elongated hole 34. When the casing cover 30 is secured to the casing body 25, the coupled apertures 33 of the cover 30 and their corresponding elongated holes 34 in the casing body 25 to form watertight passageways through the casing 5. The axial part of fasters may be passed through the watertight casing 5 by the watertight passageways created by coupled apertures 33 and elongated holes 34.

[42] The watertight passageways created by coupled apertures 33 and elongated holes 34 line up with corresponding apertures 85 of the attachment plate 82.

[43] The attachment plate 82 and casing 5 are secured to securing apertures in a board 2 or receiving nuts or similar fastener securing means (not shown) in the track mount of the board 2 by fasteners (not shown), such as bolt and the like.

[44] In order to couple the drive unit 1 to a board 2, the long axial part of the fasteners are first inserted through apertures 85 of the attachment plate 82, then through the watertight passageways created by coupled apertures 33 and elongated holes 34 of the closed casing 5 (casing body 25 with affixed casing cover 30). The tip of the fastener is then secured to the nuts or other fastener securing means in the track mount of the board 2. The head of the fastener rest on the connector brackets 83 and the end of the fasteners shank threadedly mate with the internal threads of the nuts held with the board 2.

[45] The drive unit 1 may be uncoupled from the board 2 by unscrewing the fasteners by the fastener heads located at the attachment plate 82. [46] In an embodiment, four fasteners (two per track) are used to attach the casing 5 to M8 mounting t-nuts in the track system on the board 2.

[47] The rear wall 29 of the casing body 25 comprises two apertures 55 with internal threads. Threaded cap 60 mate with the internal threads of the apertures 55 to create a hermetic and watertight connection between the apertures 55 and the cap 60. One of the apertures 55 is to access a power button (not shown) and the other aperture 55 is to access a charging port (not shown). The power button and the charging port are both housed within the casing and are accessed by removing the threaded caps 60.

[48] The motor controller 45 housed within the casing converts DC power inputted from the battery 40 into a bridge circuit for sine wave generation for the electric motor of the motor 15. This power conversion creates some unwarranted heat. In order to prevent the motor controller from overheating a heat plate is used to dissipate heat into the water. As shown in FIG. 4, the motor controller 45 is positioned on and attached to an elongated heatsink support plate 65. The heat sink plate 65 is fabricated from, e.g., an aluminum alloy for good thermal transport, or other suitable material. The heat sink plate 65 and motor controller 45 are positioned within the opening 35 of the casing 5 generally over the area where the strut 10 is coupled to the exterior wall off of the casing body 35. The arrangement transfer heat generated by the power system of the drive module 1 down the strut 10 into the water during use.

[49] As shown in FIG. 5, the casing body 25 includes a number of apertures 70 under the heat-sink plate 65 for wires from the motor controller 45 to be inserted through the apertures 70 and pass though cavity within the strut 10 to be connected to the motor of the motor 15.

[50] The heat sink plate 65 includes a number of openings or slots 75 from one side of the plate 65 to the area above the aperture 70 in the casing body so that the wires coming from the can be tucked under the motor controller 45 and to allow the wires to be sealed within the slot 75 and the apertures 70.

[51] Although the present invention has been described with reference to specific features and embodiments thereof, it is evident that various modifications and combinations can be made thereto without departing from the invention. The specification and drawings are, accordingly, to be regarded simply as an illustration of the invention as defined by the appended claims, and are contemplated to cover any and all modifications, variations, combinations, or equivalents that fall within the scope of the present invention.

Claims

WHAT IS CLAIMED IS:

1. A drive module configured for removable attachment to a flotation board and a hydrofoil, the drive module comprising: a watertight casing comprising a battery and a motor controller; the casing comprises watertight passageways through the casing to receive fasteners for removably coupling the drive module to fastener receiving means within the water engaging surface of the flotation board between a middle section and a rear section of the flotation board; a propulsion system including a strut and a motor; the strut having an upper end and a lower end, the upper end of the strut being fixedly coupled to the casing, the lower end of the strut is configured to be removably coupled to a hydrofoil; the motor being coupled to a mid-section of the strut; the motor comprising a motor and a propeller; the drive module forms an integral unit.

2. The drive module according to claim 1, wherein the upper end of the strut is fixedly interconnected to the casing by an attachment plate.

3. The drive module of claim 1, wherein the drive module is secured to the flotation board by passing fasteners through apertures in the attachment plate, though the watertight passeways of the casing and securing the tip of the fasteners in fastener receiving means within the flotation board.

4. The drive module according to claim 1, wherein the casing further comprises a heat sink plate positioned above the strut to transfer heat generated within the housing down the strut into the water during use.