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Patent Searching and Data


Title:
OUTBOARD MOTOR FOR A BOAT
Document Type and Number:
WIPO Patent Application WO/2013/150272
Kind Code:
A1
Abstract:
The invention comprises an outboard motor for a kayak comprising a chassis, the chassis comprising attachment means for attaching the chassis to the stern of a kayak, a fuel consuming engine, a generator, at least one electrical cell, wherein the fuel consuming engine drives the generator, and the generator is electrically connected to the electrical cell, a sensor, for detecting when the level of energy in the electrical cell drops below a given threshold, a starter in communication with the sensor for starting the fuel consuming engine when the drop in energy levels is detected by the sensor, wherein energy generated the generator is supplied to the electrical cell, for the purposes of boosting the energy levels of the cell and that energy is stored in the electrical cell, and a propeller assembly, comprising a motor and a propeller, wherein the motor is electrically connected to the electrical cell and is driven by power derived from the electrical cell, and the motor drives the propeller. The invention also comprises a kayak, comprising an outboard motor of the invention. The invention is best illustrated by figure 1 of the diagrams.

Inventors:
KIRKHAM ALAN (GB)
NEWTON STEVEN PAUL (PT)
BRANCO JOAO CARLOS DA CRUZ (PT)
Application Number:
PCT/GB2013/050780
Publication Date:
October 10, 2013
Filing Date:
March 26, 2013
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
KIRKHAM ALAN (GB)
NEWTON STEVEN PAUL (PT)
BRANCO JOAO CARLOS DA CRUZ (PT)
International Classes:
B63H20/00; B60K6/46; B60W20/00; B63B7/08; B63B35/71; B63H20/06; B63H20/08; B63H21/20; B63H21/21; B63H23/24; F02B61/04
Domestic Patent References:
WO2004031028A22004-04-15
Foreign References:
US7637790B12009-12-29
US20070202755A12007-08-30
US20110014829A12011-01-20
EP2147854A12010-01-27
Other References:
None
Attorney, Agent or Firm:
IP21 LIMITED (Lakeside 300Old Chapel Way,Broadland Business Park, Norwich Norfolk NR7 0WG, GB)
Download PDF:
Claims:
1 !

CLAIM

1. An outboard motor for a kayak, said outboard motor comprising a chassis, the chassis comprising attachment means for attaching the chassis to the stern of a kayak, a fuel consuming engine, driving

a generator, which is electrically connected to

at least one electrical cell, wherein the fuel consuming engine drives the generator, and the generator is electrically connected to the electrical cell, a sensor, for detecting when the level of energy stored in the electrical cell drops below a given threshold, a starter in communication with the sensor for .starting the fuel consuming engine when the drop in energy levels is detected by the sensor, wherein energy generated by the generator is supplied to the electrical cell, for the purposes of boosting the energy levels of the cell, and that energy is stored in the electrical cell, and a propeller assembly, comprising a motor, a shaft and a propeller, wherein the motor is electrically connected to the electrical cell and is driven by power derived from the electrical cell, and the motor drives the propeller, said shaft having a first end and a second end, the shaft being connected to the chassis at the first end such that the shaft may be axia!ly rotated and connected to the propeller assembly at the second end, said outboard motor further comprising a rotation controller for controlling the rotation of the shaft, and wherein the shaft may be rotated while the chassis remains static, said propeller assembly further comprising a pivot, wherein the shaft is pivotabiy

connected to the chassis via the pivot, and may be pivoted between a first in use

substantially vertical position to a second in use offset position and vice versa and wherein the movement of the shaft about the pivot is powered. 2, An outboard motor according to any of the preceding claims, further comprising a second sensor, wherein the second sensor is in communication with the fuel consuming engine, wherein when the second sensor detects the dropping of the revoiutions of the fuel consuming engine to below a given number per second, the second sensor communicates this data to a controller which sends a command to the pivot to move the shaft from the first position to the second position,

3. An outboard motor according to any of the preceding claims, further comprising a wireless controller and a wireless receiver, wherein the wireless controller is in

communication with the wireless receiver and wherein at least the rotation of the shaft is controlled wirelessiy.

4, An outboard motor according to any of the preceding claims, wherein the shaft is of adjustable length, and wherein the shaft further comprises locking means so as to enable the locking of the shaft at a chosen length.

5. An outboard motor according to any of the preceding claims, wherein the motor in the propeller is a brushless motor. 6, An outboard motor according to any of the preceding claims, further comprising at least one exterior facing power point, and wherein the outboard motor supplies power to the said power point, said power point comprising a connector for connecting an external device. 7. An outboard motor according to any of the preceding claims, wherein the starter is powered and the power is derived from the electrical cell

8. An outboard motor according to any of the preceding claims, wherein the propeller may also be driven directly by the generator.

9. An outboard motor substantially as described herein, with reference to and as illustrated by any combination of the text and/or drawings. 10, A kayak, comprising an outboard motor according to any of claims 1 -8,

1 1. A kayak, substantially as described herein, with reference to and as Illustrated by any combination of the text and/or drawings.

Description:
OUTBOARD MOTOR FOR A BOAT

The invention is an outboard motor for a boat, especially for a craft which would otherwise be manually powered, and most especially a kayak. The invention is particularly in the field of retrofit outboard motors.

Rowing boats, and in particular canoes and kayaks, have a travelling range limited chiefly by the manual strength of their users. If the user stops rowing paddling or peddling, then the boat will, if not carried along by a current, or other environmental factor, soon come to a stop.

One solution to this problem is to provide an electric engine, in the form of an outboard motor, but because of the limitations of electric battery life, these engines only last for a short time, and therefore are unlikely to last for the length of a kayaking trip, which might be a long weekend.

Kayakers and smaller boat owners have difficulty accommodating the larger size of an engine that turns. Small sailing dinghies particularly often do not have a space for a turning outboard and their tiller, In addition, the transom of a kayak is not ada ted to take such an engsne. Still further, the movement of a kayak's user is limited by the kayak itself, making use of a conventional petrol engine difficult to impossible.

The invention attempts solutions to these and other problems.

s

¾umrrj<¾ry Q,f„thg„inyent,j,o,n, in a first broad, independent aspect, the invention comprises and outboard motor for a kayak, said outboard motor comprising a chassis, the chassis comprising attachment w means for attaching the chassis to the stern of a kayak, a fuel consuming engine, driving a generator, which is electrically connected to at least one electrical cell, wherein the fuel consuming engine drives the generator, and the generator is electrically connected to the electrical cell, a sensor, for detecting when the level of energy stored in the electrical cell drops below a given threshold, a starter in communication with the sensor for starting the

15 fuel consuming engine when the drop in energy levels is detected by the sensor, wherein energy generated by the generator is supplied to the electrical cell, for the purposes of boosting the energy levels of the cell, and that energy is stored in the electrical cell, and a propeller assembly, comprising a motor, a shaft and a propeller, wherein the motor is electrically connected to the electrical cell and is driven by power derived from the 0 electrical cell, and the motor drives the propeller, said shaft having a first end and a second end, the shaft being connected to the chassis at the first end such that the shaft may be axially rotated and connected to the propeller assembly at the second end, said outboard motor further comprising a rotation controller for controlling the rotation of the shaft, and wherein the shaft may be rotated while the chassis remains static, said propeller assembly5 further comprising a pivot, wherein the shaft is pivotably connected to the chassis via the pivot, and may be pivoted between a first in use substantially vertical position to a second in use offset position and vice versa and wherein the movement of the shaft about the pivot is powered. 0 The provision of a hybrid-powered outboard motor for a kayak provides for the first time a dual fuel engine combining the instant accessibility of electricity provided by an electrical cell with the ease of use of a fuel-consuming engine, which given sufficient fuel, can last far longer than a cell alone. As a result it can be of use for longer, for example during a weekend expedition. The outboard motor and propeller comprise the whole product to be sold, but each is detachable from the other and may therefore be sold separately.

The provision of a rotatable shaft whilst the chassis remains static provides for a motor which can be mounted on a kayak which is both light and generally somewhat more laterally stable - the transfer of weight laterally about the kayak caused by the rotation of the propeller is far less than that which would be caused by the rotation of the entire outboard motor with a conventional tiller system for example, The pivoting of the shaft allows for the propeller to be raised from the water under the user's control Again, this is helpful in the shallow waters often negotiated by kayaks, stopping damage and to and tangling of the propeller.

By allowing for the raising of the propeller from the water when not in use, drag caused by the propeller shaft is eliminated - particularly useful when the user decides to paddle.

The powering of the pivot advantageously allows for the automatic lowering or raising of the propeller-bearing shaft when the propeller is actuated or halted. The provision of a powered pivot further allows for the raising and lowering of the shaft without manual involvement of the user, who will often have both hands occupied by bis paddle.

Even more preferably, the motor further comprises a second sensor, wherein the second senso is in communication with the principal motor, wherein when the second sensor detects the dropping of the revolutions of the principal motor to below a given number per second, the second sensor communicates this data to a controller which sends a command to the pivot to move the shaft from the first position to the second position.

This feature provides that the motor, when running out of fuel or being turned off, will raise the shaft and propeller assembly. This is predominantly a safety feature, ensuring the propeller isn't still spinning above wafer, where it would present a hazard.

The automatic raising of the shaft and thus also the propeller assembly in response to the dropping of revolutions of the principal motor allows for the reduction of drag when the pilot, of the kayak wants to use paddle force only or to float freely. The raising of the shaft when not in use also prevents the shaft from becoming stuck in shallow or weed choked waters where paddle force only is manifestly more appropriate,

Preferably, the motor further comprises a wireless controller and a wireless receiver, wherein the wireless controller is in communication with the wireless receiver and wherein at least the rotation of the shaft Is controlled wireiessly.

Wireless communication means are particularly advantageous because of the length of the kayak, the relatively fixed orientation of the kayak's pilot, and the fact that the said pilot Is likely to have his hands full of the paddle.

Wireless operation has a variety of useful functions offering the principal advantages of providing a waterproof communication means between said controller and said receiver, the receiver being attached to the outboard motor. Second, the wireless, remote control of the kayak is enabled meaning that the kayak can be directed to a destination unmanned which advantageously may be useful in a rescue scenario or in a scenario where a quantity of provisions needs to be transported in the kayak,

Preferably, the shaft is of adjustable length, and wherein the shaft further comprises locking means so as to enable the locking of the shaft at a chosen length.

The extendable shaft provides for compatibility with a variety of craft. Kayaks do not have transoms and are of varying heights - as such, an extendable/retractable shaft allows for compatibility with many models. Moreover, the provision of a shaft of adjustable height provides for the use of the outboard motor in shallow water, where a conventional outboard motor might trail along the ground and become damaged.

Preferably, the motor in the propellor is a brushless motor. The brushless motor is a particularly high-powered and compact, lightweight motor.

Preferably, the motor further comprises at least one exterior facing power point, and wherein the outboard motor supplies power to the said power point, said power point comprising a connector for connecting an external device. The provision of an exterior-facing power point advantageously allows the user to tap the power source of the outboard motor for other uses - this is particularly useful on an expedition where other sources of power are not available.

Preferably, the starter is powered and the power is derived from the electrical cell.

The provision of a powered starter has the particular advantage in the context of kayaks that the user does not have to reach back and perform a vigorous physical action, such as pulling a cord, which is awkward given the positioning of the outboard motor relative to the user of the kayak and further carries with it the possibility that in performing the action the kayak might unbalance or completely capsize.

Preferably, the propeller may also be driven directly by the generator.

The possibility of directly driving the generator serves to cut out any loss of energy caused by its entry into passage through and exit from an electrical cell.

The invention also comprises an outboard motor substantially as described herein, with reference to and as illustrated by any combination of the text and/or drawings.

In a second broad, Independent aspect, the invention comprises a kayak, comprising an outboard motor according to any of the preceding claims, The invention also comprises a kayak, substantially as described herein, with reference to and as illustrated by any combination of the text and/or drawings,

The invention will now be described with reference to the figures, of which: Figure 1 is diagrammatic, cross sectional side view of a part of the invention. Figure 2 is diagrammatic, cross sectional side view of a part of the invention. Figure 3 is a diagrammatic side view of a kayak bearing an outboard motor of the invention. £etajied. srip.to

At figure 3 is shown an outboard motor 2 for a Kayak (not part of the invention). The outboard motor 2 is mounted on the rear part of the Kayak's hull Figure 1 shows the chassis 4 of the outboard motor 2 in detail. The chassis 4 is made of a material selected from metals, plastics, alloys and preferably carbon fibre material or an analogue, or a mixture thereof, the key consideration being the provision of a lightweight and robust motor. Combinations of these materials may be used in the chassis 4, and appropriately in other elements of the outboard motor 2. The chassis 4 comprises an outer case 6, an inner skeleton 8 and mounting means 10, with which the outboard motor 2 may be mounted on a kayak or the like. The mounting means 10, as shown in figure 3, preferably clamps the outboard motor 2 to the hull of the kayak so that the outer case 6 cannot be tilted or rotated. In other embodiments, tilting and/or rotating may be desirable, but in the principle embodiment described here, it Is key that the chassis 4 is static and that other parts, held by or projecting out from the chassis 4 are dynamic. The mounting means 10 is adjustable in order that a single outboard motor 2 may be fitted to many differently proportioned kayaks. The outboard motor 2 is designed to be portable, and therefore preferably weighs 5 kg or less and is small, relative to the majority of outboard motors. The chassis 4 and casing S are designed to maximise shock absorption and minimise the transmission of vibrations and noise to the exterior. The outboard 2 motor is designed with kayaks in mind but is suitable for fitting onto dinghies and other small craft.

The outboard motor 2 comprises a fuel consuming engine 12 which drives a generator 14, The engine 2 is in preferred embodiments a 4 stroke engine, and preferably runs on petrol, but could potentially run on any widely available, combustible fuel. The engine 1 preferably has a capacity of approximately 35 cc, and has at least one overhead camshaft (not shown). This type of engine 2 is advantageous because it is relatively quiet, and will therefore not scare surrounding wildlife on a hunt, for example, An outboard motor 2 of this embodiment preferably has a top speed of 6-7 knots and a fuel consumption of around 0,3 litres per hour.

The generator 14, comprises an electrical ceil 16. The generator 14 preferably has a starter 18 for starting the engine 12 - here, the generator 14 is integrated into the engine 12. The engine 12 is started with a charge from the electrical cell 16. The engine 12 may be started for example by a button interface (not shown), via the tug of a rope, or via a received command signal. The starter 18 comprises a choke attached to a temperature gauge. If, on starting the engine 1 , the temperature gauge is below a certain level, which is

advantageously a pre-set level, the choke will be activated to aid the starting process. The outboard motor 2 also has on its case 6 one or more power sockets (not shown), in order that the user might use the electrical cell 16 to power other items.

The outboard motor 2 has in preferred embodiments a first fuel tank 20 and a second fuel tank (not shown), which are orientated on either side of the engine 12. one or both of which may preferably be detachable, in order to keep the weight and / or the size of the outboard motor 2 down. The tank 20 or tanks can be any practicable size, but a tank of around a five litre capacity has proved useful, because a tank this size has been found to provide enough fuel for a weekend expedition.

The generator 14 charges the electrical cell 16 which in preferred embodiments is a lithium battery, due to the lithium battery's long life. Attached to the electrical cell 16 is a sensor 22 which comprises a means of detecting when the electrical cell 16 is depleted below a certain level When the sensor 22 senses that the battery is so depleted, the sensor 22 informs a controller 24 that this is so, and the controller 24 activates the fuel engine 12 actuated by starter 18 with a command signal The fuel consuming engine 12 then serves to drive the generator 14 once more, which in turn serves to recharge the electrical cell 16, Hot air is expelled from the hot air exhaust 15, In preferred embodiments, the source of energy is switchable between the fuel consuming engine 2 only, the electrical cell 16 only, and hybrid power and power from both sources, this switchability again being advantageous in scenarios where the sound caused by the starting up of a petrol motor will be a disturbance, such as a bird-watching expedition, The sensor 22 can also be switched off altogether. Controls are provided on at least the outboard motor 2 to facilitate such switching. When the electrical ceil 16 is fully charged, its full state is detected, and

The principal use for the power stored in the electrical ceil is to drive the propeller 28, which is best illustrated at figure 2, The propeller 26 is part of propeller assembly 28, which also comprises a preferably brushless propeller motor 30, The propeller motor is housed in a water tight casing 32, which is in the hydrodyrtarnic shape of a blade and projects from the shaft 40 at an obtuse angle, The propeller assembly 28 has a heat exchanger 34 for moving away and dispersing the heat generated by the propeller motor 30. The propeller 26 is housed in a protective structure 36, in order to militate against entanglement The propeller assembly 28 comprises a convex thrust ball 38, which enables the assembly to move through the water more smoothly.

The propeller assembly 28 is connected to the chassis 4 by way of elongate shaft 40, The shaft 40 is preferably made of stainless steel and is of adjustable length, having a first portion 42 which telescopes inside a second portion 44. The shaft 40 is retained at a given length via a simple fixture, such as a helical screw 46. Cable 48 runs between generator 14 and propeller motor 30, providing electrical power to the motor, The shaft 40 and propeller assembly 28 are, in use attached to shaft head 50 and may be removed from shaft head 50 for transport and compact storage. Shaft head 50 projects from rubber sleeve 52 ( which serves to militate against the ingress of water into the interior of the casing 6, The shaft 40 may be pivoted and rotated, and to this end is secured in steering bracket 54, which is so sized and shaped to allow both movements. Rotating of the shaft 40 is facilitated by steering gears 56, which are driven by steering engine 58, which also exhausts through hot air exhaust 15. The rotation of the shaft 40 changes the orientation of the propeller 26 and the craft is thus steered. That the shaft 40 only is rotated is in contrast to prior art outboard motors, where the entire motor structure is rotated and/or raised and lowered about mounting means by a tiller.

Pivoting is effected about pivot point 60 » which is attached to a hydraulic ram 62, which is in turn driven by lift motor 64. The shaft 40 can therefore be pivoted between an up position, wherein the hydraulic ram 62 is in an extended position and the shaft: 40 is offset from or substantially parallel to the length of the hull of the kayak - in approximately a three o'clock position - and is lifted from the water as a consequence, to a down position, wherein the hydraulic ram 62 is in a contracted position and wherein the shaft 40 is nearer to being perpendicular to the hull of the kayak, for example in a five o'clock position, being, in use, submerged in water as a consequence. In some embodiments, the pivoting movement is automatic, in that when the outboard motor 2 is started, the shaft 40 will be pivoted into the water, and when the movement of the propeller 26 is stopped, the shaft 40 will be pivoted back up into the first position. When the kayak is reversing, a reversing sensor senses this motion and the hydraulic ram 62 locks the shaft 40 into position for the duration of the reversing manoeuvre.

At figure 3, it is shown that the outboard motor 2 may be controlled remotely via remote control 66. The remote control 66 can have controls for actuating and stopping the propeller 26 and for the rotation and the lifting of the shaft 40. The remote control 66 may comprise a pair of wireless transceivers 68, 70, with a first transceiver 68 bearing the remote control incorporating the remote control 66 being situated so as to be accessible to the pilot of the kayak, and a second transceiver 70 being integrated into the outboard motor 2, The two transceivers 68, 70 are in communication with one another. In use, the user enters commands via the controls 65 on the first transceiver 68, which are

communicated to the second transceiver 70 preferably wireiessly. The second transceiver 70 comprises a processor 72 which interprets the commands received by the second transceiver 70, and accordingly actuates various parts of the outboard motor 2.

Optionally, data related to the functioning of the outboard motor 2 is fed back from the outboard motor 2, travelling via the second transceiver 70 to the first transceiver 68 and being displayed on a display, in particularly preferred embodiments, it is possible to link the outboard motor 2 to a GPS system, and to have the outboard motor 2 navigate a given path in an autopilot mode using co-ordinates gleaned therefrom. The outboard motor 2 may also comprise an auto-correct facility, wherein the orientation of the propeller 26 may be adjusted, in order to counteract deviations from a given, chosen path. The autocorrect facility may in another mode be used simply to ensure that an outboard motor 2 which is clearly intended to be ensuring the kayak is travelling in a straight line is in fact so travelling; therefore slight deviation from straight - preferably 6 degrees in either direction - are corrected, in other preferred embodiments, it is possible to remotely control the outboard motor Z, either via a removable first transceiver 68, or via another mobile device, such as a telephone or a tablet PC,