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Title:
WATERCRAFT
Document Type and Number:
WIPO Patent Application WO/2014/083315
Kind Code:
A2
Abstract:
The present invention relates to a watercraft having at least one flotation device coupled to a frame having an upper surface defining a deck. The frame supports at least one first pedal assembly and at least one second pedal assembly, each pedal assembly comprising a respective pedal crank shaft. The watercraft further comprises a propeller, said propeller being operatively coupled to said pedal crank shafts such that rotation of said pedal crank shafts causes rotation of the propeller. The axis of rotation of the pedal crank shaft of the first and/or second pedal assembly is parallel to the longitudinal axis of the watercraft, said longitudinal axis extending from the centre of the bow edge of the watercraft to the centre of the stern edge of the watercraft.

Inventors:
ROBERSON LUKE (GB)
Application Number:
PCT/GB2013/052987
Publication Date:
June 05, 2014
Filing Date:
November 13, 2013
Export Citation:
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Assignee:
ROBERSON LUKE (GB)
International Classes:
B63H16/08; B63H16/18; B63H16/20
Domestic Patent References:
WO2003091098A12003-11-06
Foreign References:
US6682378B12004-01-27
Attorney, Agent or Firm:
OXLEY, Rachel et al. (33 Gutter LaneLondon, Greater London EC2V 8AS, GB)
Download PDF:
Claims:
CLAIMS

1 . A watercraft having at least one flotation device coupled to a frame having an upper surface defining a deck, said frame supporting at least one first pedal assembly and at least one second pedal assembly, each pedal assembly comprising a respective pedal crank shaft, the watercraft further comprising a propeller, said propeller being operatively coupled to said pedal crank shafts such that rotation of said pedal crank shafts causes rotation of the propeller, wherein the axis of rotation of the pedal crank shaft of the first and/or second pedal assembly is parallel to the longitudinal axis of the watercraft, said longitudinal axis extending from the centre of the bow edge of the watercraft to the centre of the stern edge of the watercraft.

A watercraft according to claim 1 wherein the first pedal assembly comprises a first looped transmission element operatively coupled to the first pedal crank shaft and the second pedal assembly comprises a second looped transmission element operatively coupled to the second pedal crank shaft, wherein the first looped transmission element is further coupled to a first common shaft and the second looped transmission element is further coupled to a second common shaft, the looped transmission elements for transmitting rotation of the respective pedal crank shaft to the respective common crank shaft such that the axis of rotation of the first and/or second common crank shaft is parallel to the longitudinal axis of the watercraft.

A watercraft according to claim 2 wherein said first and second common crank shafts are operably coupled to a transmission shaft for transmitting rotational motion to said propeller wherein the axis of rotation of said transmission shaft is perpendicular to said first and second common crank shafts.

4. A watercraft according to any one of the preceding claims wherein said propeller is mounted on a propeller shaft.

5. A watercraft according to claim 4 wherein said propeller shaft has a stowage position in which the shaft is spaced above a lower surface of said frame.

6. A watercraft according to claim 4 or 5 wherein said propeller shaft has a propulsion position in which the shaft is spaced below a lower surface of said frame.

7. A watercraft according to claim 6 wherein the propeller shaft is biased towards said propulsion position.

8. A watercraft according to any one of claims 5 to 7 wherein, in said stowage position, said propeller shaft is substantially parallel to said deck.

9. A watercraft according to any one of claims 6 to 8 wherein, in said propulsion position, said propeller shaft is substantially perpendicular to said deck and the axis of rotation of the pedal crank shaft of the first and/or second pedal assembly is parallel to the axis of rotation of the propeller.

10. A watercraft according to any one of claims 2 to 9 wherein said frame supports a plurality of first pedal assemblies and/or a plurality of second pedal assemblies, the plurality of first pedal assemblies being coupled to the first common crank shaft and the plurality of second pedal assemblies being coupled to the second common crank shaft.

1 1 . A watercraft according to claim 10 wherein the plurality of first pedal crank shafts are coaxial and/or the plurality of second pedal crank shafts are coaxial.

12. A watercraft according to any one of the preceding claims further comprising a respective seat associated with each pedal assembly, each seat arranged such that a user faces towards the longitudinal axis of the watercraft. 13. A watercraft according to any one of claims 2 to 12 wherein each of said first and second common crank shafts are spaced below the deck.

14. A watercraft having at least one flotation device coupled to a frame having an upper surface defining a deck, and a propeller connected to a propeller shaft, wherein said propeller shaft is moveable between a stowage position in which the propeller shaft is spaced above a lower surface of said frame and a propulsion position in which the shaft is spaced below a lower surface of said frame.

15. A watercraft according to claim 14 wherein the propeller shaft is biased towards said propulsion position.

16. A watercraft according to claim 14 or 15 wherein, in said stowage position, said propeller shaft is substantially parallel to said deck. 17. A watercraft according to any one of claims 14 to 16 wherein, in said propulsion position, said propeller shaft is substantially perpendicular to said deck.

18. A watercraft according to any one of claims 14 to 17 wherein said frame supports at least one first pedal assembly and at least one second pedal assembly, each pedal assembly comprising a respective pedal crank shaft, said propeller being operatively coupled to said pedal crank shafts such that rotation of said pedal crank shafts causes rotation of the propeller, wherein the axis of rotation of the pedal crank shaft of the first and/or second pedal assembly is parallel to the longitudinal axis of the watercraft, said longitudinal axis extending from the centre of the bow edge of the watercraft to the centre of the stern edge of the watercraft.

19. A watercraft according to claim 18 wherein said frame supports at least one first pedal assembly and at least one second pedal assembly, each pedal assembly comprising a respective pedal crank shaft, the watercraft further comprising an propeller, said propeller being operatively coupled to said pedal crank shafts such that rotation of said pedal crank shafts causes rotation of the propeller, wherein the axis of rotation of the pedal crank shaft of the first and/or second pedal assembly is parallel to axis of rotation of the propeller. 20. A watercraft according to claim 18 or 19 wherein the first pedal assembly comprises a first looped transmission element operatively coupled to the first pedal crank shaft and the second pedal assembly comprises a second looped transmission element operatively coupled to the second pedal crank shaft, wherein the first looped transmission element is further coupled to a first common shaft and the second looped transmission element is further coupled to a second common shaft, the looped transmission elements for transmitting rotation of the respective pedal crank shaft to the respective common crank shaft such that the axis of rotation of the first and/or second common crank shaft is parallel to the longitudinal axis of the watercraft.

21 . A watercraft according to claim 20 wherein said first and second common crank shafts are operably coupled to said propeller shaft via a transmission shaft wherein the axis of rotation of said transmission shaft is perpendicular to said first and second common crank shafts.

22. A watercraft according to any one of claims 19 to 21 wherein said frame supports a plurality of first pedal assemblies and/or a plurality of second pedal assemblies, the plurality of first pedal assemblies being coupled to the first common crank shaft and the plurality of second pedal assemblies being coupled to the second common crank shaft.

23. A watercraft according to claim 22 wherein the plurality of first pedal crank shafts are coaxial and/or the plurality of second pedal crank shafts are coaxial.

24. A watercraft according to any one of the preceding claims wherein the watercraft comprises a plurality of flotation devices. 25. A watercraft according to claim 24 wherein the watercraft comprises two elongated flotation devices, one coupled to a port side of the frame and one coupled to the starboard side of the frame with the longitudinal axes of the devices substantially parallel to the longitudinal axis of the water craft. 26. A watercraft according to any one of the preceding claims wherein the or each flotation device is an inflatable bladder.

27. A watercraft according to any one of claims 19 to 26 further comprising a respective seat associated with each pedal assembly, each seat arranged such that a user faces towards the longitudinal axis of the watercraft.

28. A watercraft according to any one of the preceding claims wherein the deck is spaced below an upper surface of the at least one flotation device. 29. A watercraft according to any one of claims 20 to 28 wherein each of said first and second common crank shafts are spaced below the deck.

30. A watercraft according to any one of the preceding claims further comprising a steering assembly having a rudder and rudder actuation means.

31 . A watercraft substantially as any one embodiment herein described with reference to the accompanying figures.

Description:
WATERCRAFT

FIELD OF THE INVENTION

The present invention relates to a watercraft. In particular, this invention relates to a human-powered watercraft that is propelled by actuation of pedals.

BACKGROUND

Watercrafts used in the leisure industry are commonly designed to provide fun and entertainment to users. Typical types of such watercraft include hydrocycles and pedalos (also known as paddle boats).

Pedalos are operated by activation of pedals that are connected to paddle wheels which in turn propel the pedalo through the water. Multi-person pedalos are available, allowing families or groups of friends, for example, to use a single pedalo together.

In multi-person pedalos, it is usual for two pedalers to sit side-by-side facing in the direction of travel. This seating arrangement is a consequence of the configuration of the pedals and the paddle wheels. While multi-person pedalos are somewhat more sociable for groups than using several single-person pedalos, the seating arrangement makes it difficult for pedalers to talk to one another easily. This is because each pedaler faces in a forward direction, so it can be difficult for pedalers to hear one another speak. This is especially true on bodies of water which also have engine-driven watercraft.

Common solutions include turning the head, but this can cause some pain to the neck especially if the position is prolonged. Sometimes pedalers twist their bodies round as an alternative solution, but this can be dangerous as the pedaler risks becoming off-balance and falling in the water. It is also more difficult to pedal when in such a contorted position, which results in a loss of forward drive. The seating arrangement in pedalos also leads to limited opportunities for eating and drinking sociably. These existing multi-person pedalos can carry more than two passengers but only two people can pedal at any one time and thus any extra passengers do not contribute to the powering of the craft - they are simply carried as extra weight. Accordingly, known multi-person pedalos are not an attractive option for larger groups.

Hydrocycles are also operated by activation of pedals. The pedals typically drive a propeller positioned under water. Hydrocycles typically accommodate one person facing forwards but multiple (i.e. two) users may be accommodated in tandem with one user facing the back of the other user. Again, this configuration does not lend itself to easy communication and socialising between users.

Navigation in shallow waters can be problematic for many sorts of watercraft. Typically, boats have a bracket which holds a propeller fixed to the structure of the boat, generally to the hull, in order to ensure that the driving force for the boat is applied predictably and securely. When transporting such crafts to and from water and when in shallow water, special care has to be taken to avoid damage. US 6,682,378 discloses variable depth propellers incorporated in a housing that can be used to avoid propeller damage in shallow water. The variation in depth provided by these propellers is small, and they must be integrated into the deck of a boat which takes up a lot of room.

An aim of the present invention is to provide a pedal-powered watercraft with a new and useful drive system configuration capable of providing a more sociable seating arrangement for an increased number of pedalling passengers. An aim of the present invention is to provide a watercraft having a new and useful propeller system suitable for use in shallow water. SUMMARY OF THE INVENTION

In a first aspect, the present invention provides a watercraft having at least one flotation device coupled to a frame having an upper surface defining a deck, said frame supporting at least one first pedal assembly and at least one second pedal assembly, each pedal assembly comprising a respective pedal crank shaft, the watercraft further comprising a propeller, said propeller being operatively coupled to said pedal crank shafts such that rotation of said pedal crank shafts causes rotation of the propeller, wherein the axis of rotation of the pedal crank shaft of the first and/or second pedal assembly is parallel to a longitudinal axis of the watercraft, said longitudinal axis extending from the centre of the bow edge of the watercraft to the centre of the stern edge of the watercraft.

As is conventional in watercrafts, the bow edge is the front/forward edge which cuts through the water as the watercraft moves in a forward direction and the bow edge is the back/rear edge which trails through the water. The watercraft also has a port side (right hand side) which is transversely opposed to a starboard side (left hand side) across the longitudinal axis of the watercraft.

By providing a watercraft in which the axis of rotation of the pedals (about the pedal crank shaft) is parallel to longitudinal axis of the watercraft and therefore parallel to the forward direction of travel (unlike in pedalos and hydrocycles in which the axis of rotation of the pedals is perpendicular to the longitudinal axis and forward direction of travel), it is no longer necessary for the user to face forwards (in the direction of travel) and, instead, the user can sit at ninety degrees to the direction of travel facing a second user. In preferred embodiments where the axis of rotation of both pedal crank shafts are parallel to the longitudinal axis of the watercraft and the forward direction of travel, the second user can also sit at ninety degrees to the direction of travel. Preferably, the first pedal assembly is on the starboard side of the watercraft and the second pedal assembly is on the port side of the watercraft. In this way, the two users can face each other instead of facing forwards, and thus it is possible for easy communication and increased socialising between the two users. Most preferably, the first pedal assembly and second pedal assembly are aligned either side of the longitudinal axis of the watercraft so that the users can directly face each other.

Preferably, the first pedal assembly comprises a first looped transmission element such as a chain or belt. This looped transmission element is operatively coupled to the first pedal crank shaft. Preferably, the second pedal assembly comprises a second looped transmission element (e.g. a chain/belt) operatively coupled to the second pedal crank shaft. The first looped transmission element is further coupled to a first common shaft and the second looped transmission element is further coupled to a second common shaft. The looped transmission elements are adapted to transmit rotation of the respective pedal crank shaft to the respective common crank shaft e.g. via a cog. In this way, the axis of rotation of the first and/or second common crank shaft is parallel to the longitudinal axis and forward direction of travel of the watercraft.

Preferably each pedal assembly comprises a free wheel or overrunning clutch which disengages the respective common crank shaft from the respective pedal crank shaft when the common crank shaft is rotating faster than the pedal crank shaft. For example, the cog which cooperates with the looped transmission elements to transmit rotation of the respective pedal crank shaft to the respective common crank shaft may incorporate a freewheel mechanism. In this way, the user can rest without the pedal crank shaft (and pedals) rotating.

Preferably said first and second common crank shafts are operably coupled to a transmission shaft for transmitting rotational motion to the propeller. Most preferably, the axis of rotation of the transmission shaft is perpendicular to said first and second common crank shafts (and the longitudinal axis of the watercraft). Rotational motion may be transferred from the common crank shafts to the transmission shaft using a right-angled gear.

In preferred embodiments, each of said first and second common crank shafts are spaced below the deck. This ensures that users cannot injure themselves by coming into contact with the rotating common shafts and also reduces the centre of gravity of the watercraft thus improving stability.

As used herein, the term 'propeller' means any suitable impeller capable of using rotational motion to provide thrust to a watercraft.

In preferred embodiments, the propeller is mounted on a propeller shaft. Preferably, the propeller shaft is mounted on the transmission shaft and rotational motion from the transmission shaft is transferred to the propeller shaft. Preferably, rotational motion from the transmission shaft is transferred to the propeller shaft using a right-angled gear.

In especially preferred embodiments, rotational motion from the propeller shaft is transferred to the propeller using a right-angled gear.

In most preferred embodiments, a propeller arm is provided extending between the right angled gears at either end of the propeller shaft. This propeller arm prevents the right angled gear proximal the propeller from rotating as torque is transmitted along the propeller shaft. It also strengthens the propeller shaft/propeller assembly.

In preferred embodiments, the propeller shaft has a stowage position in which the shaft (and arm) is spaced above a lower surface of said frame (and preferably above a lower surface of said at least one flotation device). Preferably, in the stowage position, the propeller shaft is substantially parallel to the deck i.e. the propeller shaft is substantially horizontal. Preferably, when the watercraft is in storage or transit between bodies of water, the propeller is protected within the frame i.e. below the deck but above a lower surface of the frame.

Preferably, the propeller shaft has a propulsion position in which the shaft (and arm) is spaced below a lower surface of said frame (and preferably below a lower surface of said at least one flotation device). In this propulsion position, during use, the propeller imparts forward thrust to the watercraft to propel it through the water.

Preferably, the propeller shaft is substantially perpendicular to the deck in the propulsion position i.e. the propeller shaft is substantially vertical in the water. When the propeller shaft is in this maximum propulsion position, the axis of rotation of the pedal crank shaft of the first and/or second pedal assembly is parallel to the axis of rotation of the propeller. In this position, the propeller can impart the maximum forward thrust to the watercraft.

Preferably, the propeller shaft (and arm) is biased towards the propulsion position e.g. by the weight of the propeller.

Preferably, the propeller shaft is moveable e.g. pivotable between the stowage position and the propulsion position. For example, the transmission shaft may be mounted on the frame on bearing hinges to allow pivotable movement of the propeller shaft (and right- angled gear) between the stowage and propulsion positions. In these embodiments, the propeller shaft is biased towards the propulsion position by the thrust of the propeller causing it to rotate around the bearing hinge until it reaches the propulsion position. Preferred embodiments comprise locking means to secure the propeller shaft (and arm) in the stowage position. The locking means can be used to secure the propeller shaft in the stowage position during storage and transport of the watercraft to ensure that the propeller shaft is securely maintained in a protected position above the lower surface of the at least one flotation device within the frame of the watercraft. In especially preferred embodiments, the locking means further comprises means for moving the propeller shaft from the propulsion position towards the stowage position. For example, the locking means may comprise a pulley system for manually raising the propeller shaft into an intermediate position between the stowage and propulsion positions. The users can operate the pulley system e.g. using a lever on the deck to raise the propeller shaft e.g. in the event of encountering shallow water.

Preferred embodiments comprise restriction means to restrict movement of the propeller shaft (and arm) past the propulsion position and/or one or more intermediate positions. When the propeller is rotating, the thrust generated drives the propeller shaft away from the stowage position. The restriction means limit the movement generated by the propeller thrust so that the propeller shaft is maintained in the propulsion position to ensure reliable and consistent forward thrust during use of the watercraft. The restriction means may also be used to secure the propeller shaft in one or more intermediate positions between the stowage and propulsion positions to allow the propeller to impart forward thrust to the watercraft in shallow water.

The propeller shaft is moveable from the propulsion position and/or one or more intermediate position in the event that the propeller and/or propeller shaft make contact with an obstacle e.g. a submerged object or the floor bed of the body of water. In especially preferred embodiments, a propeller guard is provided to protect the propeller from a direct contact with an obstruction. Contact between the propeller guard and an obstruction will force the propeller shaft away from the propulsion or intermediate position towards the stowage position. In this way, damage to the propeller/propeller shaft can be minimised.

In a second aspect, the present invention provides a watercraft having at least one flotation device coupled to a frame having an upper surface defining a deck, and a propeller connected to a propeller shaft, wherein said propeller shaft is moveable between a stowage position in which the propeller shaft is spaced above a lower surface of said frame (and preferably above a lower surface of said at least one flotation device) and a propulsion position in which the shaft is spaced below a lower surface of said frame (and preferably above a lower surface of said at least one flotation device).

By providing a propeller on a propeller shaft which is movable between a stowage position and a propulsion position, it is possible to ensure that the propeller is protected by the frame during transit and storage but that it is available to provide thrust in the prolusion position to ensure rapid progress of the watercraft during use.

As used herein, the term 'propeller' means any suitable impeller capable of using rotational motion to provide thrust to a watercraft. Preferably, in the stowage position, the propeller shaft is substantially parallel to the deck i.e. the propeller shaft is substantially horizontal. Preferably, the propeller shaft is substantially perpendicular to the deck in the propulsion position i.e. the propeller shaft is substantially vertical in the water. In this position, the propeller can impart the maximum forward thrust to the watercraft.

Preferably, the propeller shaft is biased towards the propulsion position e.g. by the weight of the propeller. Preferably, the propeller shaft is moveable e.g. pivotable between the stowage position and the propulsion position. In these embodiments, the propeller shaft is biased towards the propulsion position by the thrust of the propeller causing it to rotate around the pivot until it reaches the propulsion position.

Preferred embodiments comprise locking means to secure the propeller shaft in the stowage position. The locking means can be used to secure the propeller shaft in the stowage position during storage and transport of the watercraft to ensure that the propeller shaft is securely maintained in a protected position above the lower surface of the at least one flotation device within the frame of the watercraft. In especially preferred embodiments, the locking means further comprises means for moving the propeller shaft from the propulsion position towards the stowage position. For example, the locking means may comprise a pulley system for manually raising the propeller shaft into an intermediate position between the stowage and propulsion positions. The users can operate the pulley system e.g. using a lever on the deck to raise the propeller shaft e.g. in the event of encountering shallow water.

Preferred embodiments comprise restriction means to restrict movement of the propeller shaft past the propulsion position and/or one or more intermediate positions. When the propeller is rotating, the thrust generated drives the propeller shaft away from the stowage position. The restriction means limit the movement generated by the propeller thrust so that the propeller shaft is maintained in the propulsion position to ensure reliable and consistent forward thrust during use of the watercraft. The restriction means may also be used to secure the propeller shaft in one or more intermediate positions between the stowage and propulsion positions to allow the propeller to impart forward thrust to the watercraft in shallow water. The propeller shaft is moveable from the propulsion position and/or one or more intermediate position in the event that the propeller and/or propeller shaft make contact with an obstacle e.g. a submerged object or the floor bed of the body of water. In especially preferred embodiments, a propeller guard is provided to protect the propeller from a direct contact with an obstruction. Contact between the propeller guard and an obstruction will force the propeller shaft away from the propulsion or intermediate position towards the stowage position. In this way, damage to the propeller/propeller shaft can be minimised.

Preferably, the frame of the watercraft of the second aspect supports at least one first pedal assembly and at least one second pedal assembly. Each pedal assembly comprises a respective pedal crank shaft, and the propeller is operatively coupled to said pedal crank shafts such that rotation of said pedal crank shafts causes rotation of the propeller. The axis of rotation of the pedal crank shaft of the first and/or second pedal assembly is parallel to a longitudinal axis of the watercraft, said longitudinal axis extending from the centre of the bow edge of the watercraft to the centre of the stern edge of the watercraft.

As is conventional in watercrafts, the bow edge is the front/forward edge which cuts through the water as the watercraft moves in a forward direction and the bow edge is the back/rear edge which trails through the water. The watercraft also has a port side (right hand side) which is transversely opposed to a starboard side (left hand side) across the longitudinal axis of the watercraft.

By providing a watercraft in which the axis of rotation of the pedals (about the pedal crank shaft) is parallel to longitudinal axis of the watercraft and therefore parallel to the forward direction of travel (unlike in pedalos and hydrocycles in which the axis of rotation of the pedals is perpendicular to the longitudinal axis and forward direction of travel), it is no longer necessary for the user to face forwards (in the direction of travel) and, instead, the user can sit at ninety degrees to the direction of travel facing a second user. In preferred embodiments where the axis of rotation of both pedal crank shafts are parallel to the longitudinal axis of the watercraft and the forward direction of travel, the second user can also sit at ninety degrees to the direction of travel. Preferably, the first pedal assembly is on the starboard side of the watercraft and the second pedal assembly is on the port side of the watercraft. In this way, the two users can face each other instead of facing forwards, and thus it is possible for easy communication and increased (and higher quality) socialising between the two users. Most preferably, the first pedal assembly and second pedal assembly are aligned either side of the longitudinal axis of the watercraft so that the users can directly face each other.

Preferably, the first pedal assembly comprises a first looped transmission element such as a chain or belt. This looped transmission element is operatively coupled to the first pedal crank shaft. Preferably, the second pedal assembly comprises a second looped transmission element (e.g. a chain/belt) operatively coupled to the second pedal crank shaft. The first looped transmission element is further coupled to a first common shaft and the second looped transmission element is further coupled to a second common shaft. The looped transmission elements are adapted to transmit rotation of the respective pedal crank shaft to the respective common crank shaft, e.g. via a cog. In this way, the axis of rotation of the first and/or second common crank shaft is parallel to the longitudinal axis and the forward direction of travel of the watercraft.

Preferably each pedal assembly comprises a free wheel or overrunning clutch which disengages the respective common crank shaft from the respective pedal crank shaft when the common crank shaft is rotating faster than the pedal crank shaft. For example, the cog which cooperates with the looped transmission elements to transmit rotation of the respective pedal crank shaft to the respective common crank shaft may incorporate a free- wheel mechanism. In this way, the user can rest without the pedal crank shaft (and pedals) rotating.

Preferably said first and second common crank shafts are operably coupled to a transmission shaft for transmitting rotational motion to the propeller. Most preferably, the axis of rotation of the transmission shaft is perpendicular to said first and second common crank shafts (and the longitudinal axis of the watercraft). Rotational motion may be transferred from the common crank shafts to the transmission shaft using a right-angled gear.

In preferred embodiments, each of said first and second common crank shafts are spaced below the deck. This ensures that users cannot injure themselves by coming into contact with the rotating common shafts and also reduces the centre of gravity of the watercraft thus improving stability.

Preferably, the propeller shaft is mounted on the transmission shaft and rotational motion from the transmission shaft is transferred to the propeller shaft. Preferably, rotational motion from the transmission shaft is transferred to the propeller shaft using a right-angled gear.

In especially preferred embodiments, the rotational motion from the propeller shaft is transferred to the propeller using a right-angled gear.

In most preferred embodiments, a propeller arm is provided extending between the right angled gears at either end of the propeller shaft. This propeller arm prevents the right angled gear proximal the propeller from rotating as torque is transmitted along the propeller shaft. It also strengthens the propeller shaft/propeller assembly. Preferably, the transmission shaft is mounted on the frame using bearing hinges which allow pivotable movement of the propeller shaft/arm (and the right-angled gear) between the stowage and propulsion positions.

In preferred embodiments of the first and second aspects, the frame supports a plurality of first pedal assemblies. Each of the plurality of first pedal assemblies is operably coupled to the first common crank shaft. In preferred embodiments, the frame supports a plurality of second pedal assemblies. Each of the plurality of second pedal assemblies is operably coupled to the second common crank shaft.

By providing a plurality of first and/or second pedal assemblies, the number of users can be increased so that the watercraft can accommodate a group of friends or a family. Preferably, the first pedal crank shafts in the plurality of first pedal assemblies are coaxial. This results in the first pedal assemblies being aligned with one another in a row. Preferably, the second pedal crank shafts in the plurality of second pedal assemblies are coaxial. This results in the second pedal assemblies being aligned with one another in a row.

Most preferably, the watercraft is provided with a row of (two or more) first pedal assemblies on the starboard side of the watercraft and a row of (two or more) second pedal assemblies on the port side of the watercraft. In this way a number (four or more) of users can face each other across the deck of the watercraft to engage in conversation and socialising. Preferably, each first pedal assembly is directly opposed to a second pedal assembly across the longitudinal axis of the watercraft so that the users can directly face each other. In preferred embodiments of the first and second aspects, the watercraft comprises a plurality of flotation devices. In most preferred embodiments, the watercraft comprises two flotation devices, one provided at the starboard side of the watercraft and one provided at the port side of the watercraft.

Most preferably, the watercraft comprises two elongated flotation devices, with the longitudinal axes of the devices substantially parallel to the axis of rotation of the pedal crank shafts and parallel to the longitudinal axis of the watercraft. By providing elongated flotation devices on the port and starboard sides of the watercraft, the stability of the watercraft is increased.

Preferably, the or each flotation device is an inflatable bladder e. g. a PVC bladder, [other forms of flotation devises could be used. Including rigid polyethylene injection molded tubes] Preferably, each flotation device is compartmentalised so that if one compartment fails e.g. bursts or leaks, the remaining compartment(s) prevents the watercraft from sinking or capsizing.

Whilst users could pedal the watercraft in a standing position, preferably, in the first and second aspects, the watercraft comprises a respective seat associated with each pedal assembly, each seat arranged such that a user faces towards the longitudinal axis of the watercraft. This increases comfort for the user. The deck may further support handles or rails which a user may grip to improve their balance. There may be individual handles associated with each pedal assembly or there may be one or more elongated rails aligned with the longitudinal axis of the watercraft for shared use.

In preferred embodiments of the first and second aspects, the deck is spaced below an upper surface of the at least one flotation device. This improves stability of the watercraft by lowering the centre of gravity. Preferably, in the first and second aspects, the deck further supports a table and/or bar e.g. between the first and second pedal assemblies. This allows the consumption of food and/or beverage during use. The deck may also support one or more handrail(s) to improve user stability.

In preferred embodiments of the first and second aspect, the frame is formed of a light weight material such as aluminium.

Preferably, in the first and second aspects, the watercraft further comprises a steering assembly having a rudder and rudder actuation means. The rudder actuation means may be, for example, a steering wheel or a tiller. It may be positioned at the stern but is preferably positioned at the bow. The rudder actuation means is preferably joined to the rudder via cables. The steering assembly allows control of the direction of travel of the watercraft.

Preferably, in preferred embodiments of the first and second aspects, the watercraft further comprises a battery, preferably a solar charged battery such as a lithium ion storage battery. The battery may be used to propel the water craft in addition or as an alternative to pedal power. It may also be used to power a stereo system and/or a refrigerator and/or lights.

In preferred embodiments of the first and second aspects, the watercraft comprises a GPS to allow satellite tracking of the watercraft. Preferably, the watercraft of the first or second aspect can be dismantled into various component parts to assist in transportation of the watercraft. Preferably, the water craft can be dismantled into the at least one flotation device and the frame (carrying the pedal assemblies). Preferably, the frame can be further dismantled into three main parts (bow, middle and stern). Preferably, any table or hand rails on the frame can be dismantled from the deck.

Preferred embodiments of the present invention will now be described with reference to the accompanying drawings in which:

Figure 1 is an aerial cross-sectional schematic diagram of a watercraft according to an embodiment of the invention with the propeller shaft in a stowage position.

Figure 2 is an aerial cross-sectional schematic diagram of a watercraft according to an embodiment of the invention with the propeller shaft in a propulsion position.

Figure 3 is a side-on cross-sectional schematic diagram of the watercraft as in Figure 1 . Figure 4 is a side-on cross-sectional schematic diagram of the watercraft as in Figure 2.

DETAILED DESCRIPTION

A first embodiment of the present invention is shown in Figures 1 to 4. The watercraft 1 has two flotation devices 3 coupled to a frame 5 having an upper surface defining a deck 7.

The two flotation devices 3 are located either side of the watercraft 1 . In line with conventional terminology, the watercraft 1 described herein has a bow edge 9 at the front edge of the watercraft 1 , which cuts through the water as the watercraft 1 moves in a forward direction, and a stern edge 1 1 , which is the back edge of the watercraft 1 that trails the front edge as the watercraft 1 moves in a forward direction. Thus, the watercraft 1 has a longitudinal axis 12 extending from the centre of the bow edge 9 of the watercraft 1 to the centre of the stern edge 1 1 of the watercraft 1 . The watercraft 1 also has a port side 13 on the right hand side which is transversely opposed to a starboard side 15 on the left hand side across the longitudinal axis 12 of the watercraft 1 . Therefore, one of the flotation devices 3 is provided at the starboard side 15 of the watercraft 1 and one is provided at the port side 13 of the watercraft 1 .

The flotation devices 3 are elongated, and in this instance have a substantially circular cross-section when inflated. In other embodiments a different cross-section may be useful, and may vary along the length of the flotation device 3. In the present embodiment, the elongated axes of the flotation devices 3 are substantially parallel to the longitudinal axis 12 of the watercraft 1 . By providing elongated flotation devices 3 on the port 13 and starboard 15 sides of the watercraft 1 , the stability of the watercraft 1 is increased.

Each flotation device 3 is an inflatable bladder, in this embodiment a PVC bladder or pontoon. Each flotation device 3 is compartmentalised so that if one compartment fails e.g. bursts or leaks, the remaining compartment(s) prevents the watercraft 1 from sinking or capsizing. In the present embodiment, there are two such compartments in each flotation device 3.

The deck 7 is spaced below an upper surface of the flotation devices 3 as can be seen in Figures 3 and 4. This improves stability of the watercraft 1 especially when users move across the deck 7. In the present embodiment, the deck 7 is supported halfway down the inflated flotation devices 3. This allows easy boarding for users direct from the shore line. The flotation devices are secured to the frame at designated points using D-rings.

The deck 7 of the watercraft 1 of the present embodiment is substantially flat where a user is intended to move. In other embodiments, the deck 7 may have several levels at different heights. In particular, the watercraft 1 of the present embodiment has a space toward the stern edge 1 1 of the watercraft 1 capable of accommodating standing passengers. The deck 7 further supports rails (not shown) which a user may grip to improve their balance. The elongated rails are aligned with the longitudinal axis of the watercraft 1 for shared use. The frame 5 is formed of a light weight material such as aluminium. The total weight of the watercraft 1 of the preferred embodiment is less than 100 kg. This makes it easier for one or two people to prepare and launch the watercraft 1 . Despite the lightweight nature of the watercraft 1 , it is sufficiently strong to accommodate up to 8 people. The frame 5 supports three first pedal assemblies 17 and three second pedal assemblies 19 (in total, six pedal assemblies 17, 19). Only the first pedal assemblies are shown in Figures 3 and 4. Each first pedal assembly 17 has a respective pedal crank shaft 21 as shown in Figures 3 and 4. The second pedal assemblies also have a respective pedal crank shaft 21 ' (not shown).

The watercraft 1 also has a propeller 23 that is operatively coupled to the pedal crank shafts 21 , 21 ' so that rotation of the pedal crank shafts 21 , 21 ' causes rotation of the propeller 23. The axes of rotation of the pedal crank shafts 21 , 21 ' of the first and second pedal assemblies 17, 19 are parallel to the longitudinal axis 12 of the watercraft 1 . The axes of rotation of the pedal crank shafts 21 , 21 ' are also parallel to the elongated direction of the flotation devices 3.

By providing a watercraft 1 in which the axis of rotation of pedals 25 (about the pedal crank shaft 21 , 21 ') is parallel to a longitudinal axis 12 of the watercraft 1 and therefore parallel to the forward direction of travel, it is no longer necessary for the user to face forwards in the direction of travel and, instead users can sit at ninety degrees to the direction of travel. It is possible for users on the port side 13 to directly face users on the starboard side 15, 13. While in the present embodiment six pedal assemblies 17, 19 are provided, the present invention is not limited to this value. The skilled person will appreciate that fewer or more pedal assemblies 17, 19 could suitably be provided, so that the number of users can be increased or decreased as appropriate so that the watercraft 1 can accommodate a couple, group of friends, or a family.

The first pedal assemblies 17 are on the starboard side 15 of the watercraft 1 and are shown in Figures 3 and 4. The second pedal assemblies 19 are on the port side 13 of the watercraft 1 and are not shown in Figures 3 and 4 but have the same features as the first pedal assemblies. The first pedal crank shafts 21 in the first pedal assemblies 17 are coaxial. This results in the first pedal assemblies 17 being aligned with one another in a row. The second pedal crank shafts 21 ' in the second pedal assemblies 19 are coaxial. This results in the second pedal assemblies 19 being aligned with one another in a row. In this way, users can face towards each other instead of facing forwards, and thus it is possible for easy communication and increased socialising between users. This arrangement means that it is not necessary for users to turn their heads, or twist their bodies, in order to communicate readily with another user. The first pedal assemblies 17 and second pedal assemblies 19 are aligned either side of the longitudinal axis of the watercraft 1 so that the users can directly face each other across the deck 7 of the watercraft 1 to engage in conversation and socialising. Each first pedal assembly 17 is directly opposed to a second pedal assembly 19 across the longitudinal axis 12 of the watercraft 1 so that the users can directly face each other.

There is a seat 27 associated with each pedal assembly 17, 19, each seat 27 arranged such that a user faces towards the longitudinal axis of the watercraft 1 . This increases comfort for the user. In the present embodiment, the seats 27 are raised above the pedals 25 by a seat support member 29. Cycle saddles may be provided as seats 27 for comfort. A number of suitable seat types will be apparent to the skilled person. Furthermore, seat heights are adjustable within the support member 29. Each of the first pedal assemblies 17 has a first looped transmission element 31 which is a chain. Each looped transmission element 31 is operatively coupled to the respective pedal crank shaft 21 of the first pedal assembly 17. Each of the second pedal assemblies 19 has a second looped transmission element 31 ' (e.g. a chain/belt) operatively coupled to the respective pedal crank shaft 21 ' of the second pedal assembly 19 (not shown in the Figures). The first looped transmission elements 31 are also coupled to a first common shaft 35 and the second looped transmission elements 31 ' are coupled to a second common shaft 37. The looped transmission elements 31 , 31 ' are adapted to transmit rotation of the respective pedal crank shafts 21 , 21 ' to the respective common crank shafts 35, 37 via respective cogs. In this way, the axis of rotation of the first and second common crank shafts 35, 37 is parallel to the longitudinal axis 12 and forward direction of travel of the watercraft 1 .

Each cog adapted to transmit rotation of the respective pedal crank shafts 21 , 21 ' to the respective common crank shafts 35, 37 has a free wheel mechanism 39 which disengages the respective common crank shaft 35, 37 from the respective pedal crank shaft 21 , 21 ' when the common crank shaft 35, 37 is rotating faster than the pedal crank shaft 21 . In this way, the user can rest without the pedal crank shaft 21 (and pedals 25) rotating. The first and second common crank shafts 35, 37 are operably coupled to a transmission shaft 41 for transmitting rotational motion to the propeller 23. The axis of rotation of the transmission shaft 41 is perpendicular to the first and second common crank shafts 35, 37 (and the longitudinal axis 12 of the watercraft 1 ). In use, rotational motion is transferred from the common crank shafts 35, 37 to the transmission shaft 41 using a right- angle gear 43.

Each of the first and second common crank shafts 35, 37 are spaced below the deck 7. This ensures that users cannot injure themselves by coming into contact with the rotating common shafts 35, 37 and also reduces the centre of gravity of the watercraft 1 thus improving stability.

The propeller 23 is mounted on a propeller shaft 45 via a right-angled gear. The propeller shaft 45 is mounted on the transmission shaft 41 through a right-angle gear 47 and in use rotational motion from the transmission shaft 41 is transferred to the propeller shaft 45 through the right-angle gear 47.

A rigid propeller arm (not shown) is provided extending between the right angled gear proximal the propeller 23 and the right angle gear 47 on the transmission shaft. This propeller arm prevents the right angled gear proximal the propeller 23 from rotating as torque is transmitted along the propeller shaft 45. It also strengthens the propeller shaft/propeller assembly. The propeller shaft 45 has a stowage position (Figures 1 and 3). In this position, the propeller shaft 45 (and arm) is spaced within the frame above a lower surface the flotation devices 3. In the stowage position, the propeller shaft 45 is contained within the frame and is substantially parallel to the deck 7 i.e. the propeller shaft 45 is substantially horizontal. In this way, when the watercraft 1 is in storage or transit between bodies of water, the propeller 23 can be protected by the deck 7.

The propeller shaft 45 has a propulsion position (Figure 2 and 4) in which the propeller shaft 45 (and arm) is spaced below a lower surface of the flotation devices 3. In this propulsion position, during use, the propeller 23 imparts forward thrust to the watercraft 1 to propel it through the water.

As can be seen most clearly in Figure 4, the propeller shaft 45 is substantially perpendicular to the deck 7 in the propulsion position i.e. the propeller shaft 45 is substantially vertical in the water. When the propeller shaft 45 is in this maximum propulsion position, the axes of rotation of the pedal crank shafts 21 of the first and second pedal assemblies 17, 19 are parallel to the axis of rotation of the propeller 23. In this position, the propeller 23 can impart the maximum forward thrust to the watercraft 1 .

The propeller shaft 45 (and arm) is biased towards the propulsion position by the weight of the propeller 23 and also by the thrust of the propeller when in use.

In this embodiment, the propeller shaft 45 (and arm) is moveable under pivoting motion between the stowage position and the propulsion position (Figure 4, arrow). The propeller shaft 45 is mounted on a bearing hinge 49 on the transmission shaft 41 to allow it to pivot between the stowage and propulsion positions. The pivoting causes no interruption in the users cycling The propeller shaft 45 and propeller 23 are located toward the stern edge 1 1 of the watercraft 1 .

Locking means are provided to secure the propeller shaft 45 in the stowage position. Various forms of suitable locking means will be apparent to the skilled person.

Preferred embodiments comprise restriction means 51 (Figures 3 and 4) to restrict movement of the propeller shaft past the propulsion position. When the propeller is rotating, the thrust generated drives the propeller shaft away from the stowage position. The restriction means limit the movement generated by the propeller thrust so that the propeller shaft is maintained in the propulsion position to ensure reliable and consistent forward thrust during use of the watercraft. The restriction means may also be used to secure the propeller shaft in one or more intermediate positions between the stowage and propulsion positions to allow the propeller to impart forward thrust to the watercraft in shallow water. The propeller shaft is moveable from the propulsion position and/or one or more intermediate position in the event that the propeller 23 and/or propeller shaft 45 make contact with an obstacle e.g. a submerged object or the floor bed of the body of water. A propeller guard (not shown) is provided to protect the propeller from a direct contact with an obstruction. Contact between the propeller guard and an obstruction will force the propeller shaft 45 away from the propulsion or intermediate position towards the stowage position. In this way, damage to the propeller/propeller shaft can be minimised. Preferably, the locking means comprises a pulley system for manually raising the propeller shaft into an intermediate position between the stowage and propulsion positions. The users can operate the pulley system e.g. using a lever on the deck to raise the propeller shaft e.g. in the event of encountering shallow water. The watercraft 1 of the present embodiment has a steering assembly having a rudder

53, located toward the stern edge 1 1 , and rudder actuation means. The rudder actuation means is a steering wheel 55 positioned toward the bow edge 9. The steering wheel 55 is joined to the rudder 53 via cables, and is supported above the deck 7 by a steering support member 57. The skilled person will recognize that the steering support member 57 can take a number of forms. This steering assembly allows control of the direction of travel of the watercraft 1 . There is sufficient space around the steering wheel 55 and steering support member 57 to accommodate a non-pedalling, steering passenger.

The watercraft 1 of the present embodiment can be assembled and disassembled into a kit of parts. The watercraft 1 is made up of six main parts; two flotation devices, the bow part of the frame carrying steering assembly, the middle part of the frame carrying the pedal assemblies, the stern part of the frame carrying the propeller shaft and the table/handrails. The ability to disassemble the watercraft 1 into parts improves ease of transportation. In particular, the watercraft 1 of the present embodiment can be disassembled into parts capable of fitting onto a double size pallet or into a large van, obviating the need for a trailer.

The skilled person will appreciate that the described embodiments are not the only means of putting the invention into effect and obvious variations will become apparent using routine skill in light of the general teachings described herein.