JET POWERED WATERCRAFT CONTROL MECHANISM

Abstract

A control system for a jet propelled watercraft comprising a hull with a transom and water jet unit, the control system comprising, as a transom mountable unit, a tiller controlled thrust vectoring nozzle and an actuator controlled jet deflection member for forward direction steering and reversing respectively of the jet propelled watercraft.

Claims

1. A watercraft comprising: a hull, a jet propulsion unit comprising a water jet outlet nozzle at the stern of the hull, a control mechanism mounted relative to the hull to steer the watercraft when being propelled by the propulsion unit, the control mechanism comprising a thrust vectoring nozzle external of the hull adjacent the water jet outlet nozzle and having an inlet to receive water from the water jet outlet nozzle and a passage to an outlet of the thrust vectoring nozzle, the thrust vectoring nozzle able to re-direct the water jet leaving the hull controlled by a tiller stock secured to and projecting upwardly from the thrust vectoring nozzle and a tiller coupled (directly or indirectly) to the tiller stock to allow a person to manually move the tiller for controlling the operational direction of the thrust vectoring nozzle to control the direction of the water jet leaving the watercraft.

2. (canceled)

3. The watercraft as claimed in claim 1 wherein the water jet outlet nozzle is located at or near the bottom of the hull at the stern of the hull and the tiller stock projects upwardly from the thrust vectoring nozzle.

4. The watercraft as claimed in claim 1 wherein the tiller stock and thrust vectoring nozzle are pivotally mounted to the water jet outlet nozzle and the hull.

5. (canceled)

6. (canceled)

7. (canceled)

8. The watercraft as claimed in claim 1 wherein the tiller is indirectly coupled to the tiller stock in a manner to create a mechanical advantage between the tiller and the tiller stock.

9. (canceled)

10. The watercraft as claimed in claim 1 wherein the control mechanism comprising a water jet deflector external of the hull adjacent the water jet outlet nozzle, the water jet deflector shaped and configured and mounted for movement relative to the hull and the water jet outlet nozzle between (a) an operative condition presented in the water jet flow path exiting the water jet nozzle to deflect the water jet sufficiently to be able to cause the watercraft to travel through water in a reverse direction, and (b) an inoperative condition where it is not in the water jet flow path.

11. The watercraft as claimed in claim 10 wherein the water jet deflector is mounted relative to the hull of the vessel for hinged movement between the operative and in-operative conditions.

12. The watercraft as claimed in claim 11 wherein the hinged movement is about an axis of rotation that is horizontal and perpendicular to the centreline of the hull.

13. (canceled)

14. The watercraft as claimed in claim 10 wherein the water jet deflector is controlled for hinged movement by a reverse stock, co-axially mounted the tiller stock, coupled to the water jet deflector, the reverse stock able to rotate independently of the tiller stock and relative to the hull to cause the water jet deflector to move between its operative and inoperative conditions.

15. The watercraft as claimed in claim 14 wherein the reverse stock is coupled to the water jet deflector by a coupling mechanism of or comprising a 4-bar-chain configuration.

16.-34. (canceled)

35. The watercraft as claimed in claim 1 wherein the control mechanism is secured to the transom of the hull as a unit.

36. The watercraft as claimed in claim 10 wherein the control mechanism includes a base plate by which the water jet deflector is mounted in a manner to be able to rotate in a hinged manner relative to the hull and a transom plate extending upwardly from the base plate and by which the jet vectoring nozzle and the tiller stock and reverse stock is mounted for rotation relative to the hull.

37. The watercraft as claimed in claim 36 wherein the base plate is hinged to the transom plate in a manner so that the angle between them can be varied and can set.

38. The watercraft as claimed in claim 36 wherein the base plate is hinged to the transom plate in a manner so that the angle between them can be varied and can set yet the disposition of the tiller stock and the reverse stock and the water jet deflector and the jet vectoring nozzle remains the same.

39. The watercraft as claimed in claim 1 wherein the jet propulsion unit includes a shaft driven impeller coupled to an electric motor.

40. (canceled)

41. A watercraft comprising: a hull, a jet propulsion unit having a water jet outlet nozzle at the stern of the hull, a control mechanism mounted to said hull to steer the watercraft when being propelled in a forward direction by the propulsion unit, the control mechanism comprising a thrust vectoring nozzle rotationally mounted relative to the hull having an inlet to receive the water jet and a passage to an outlet of the thrust vectoring nozzle to redirect the water jet, a tiller stock rotatable relative the hull and directly or indirectly coupled to and projecting upwardly from the thrust vectoring nozzle, a tiller coupled to the tiller stock to allow a person to manually move the tiller for controlling the rotational position of the tiller stock and hence the thrust vectoring nozzle relative the hull thereby controlling the direction of forward movement of the watercraft.

42. A watercraft comprising: a hull, a jet propulsion unit having a water jet outlet nozzle at the stern of the hull, a thrust vectoring nozzle rotatably mounted relative to the hull and having an inlet to receive a water jet from the water jet outlet nozzle and a passage to an outlet of the thrust vectoring nozzle to redirect the water jet, a tiller stock projecting upwardly from the thrust vectoring nozzle to control and cause the thrust vectoring nozzle to rotate relative the water jet outlet nozzle, a tiller extending from the tiller stock to allow a person to manually move the tiller to control the rotational position of the tiller stock and the thrust vectoring nozzle.

43. A control mechanism for a jet powered watercraft having a hull with a water jet outlet nozzle, to mount to the hull to steer the watercraft when being propelled by the propulsion unit, the control mechanism comprising a. a thrust vectoring nozzle to locate external of the hull adjacent the waterjet outlet nozzle and having an inlet to receive water from the water jet outlet nozzle and a passage to an outlet of the thrust vectoring nozzle the outlet able to re-direct the waterjet leaving the hull, b. a tiller stock coupled to and projecting upwardly from the thrust vectoring nozzle, and c. a tiller coupled to the tiller stock to allow a person to manually move the tiller for controlling the direction of the waterjet leaving the watercraft.

44. A control mechanism as claimed in claim 17 further comprising a water jet deflector to locate external of the hull adjacent the water jet outlet nozzle, the water jet deflector shaped and configured for movement (preferably rotational) relative to the hull and the water jet outlet nozzle between (a) an operative condition presented in the water jet flow path exiting the water jet nozzle to deflect the water jet sufficiently to be able to cause the watercraft to travel through water in a reverse direction, and (b) an inoperative condition where it is not in the water jet flow path.

45. A control mechanism for a jet powered watercraft having a hull with a water jet outlet nozzle and comprising a water jet deflector to locate external of the hull adjacent the water jet outlet nozzle, the water jet deflector shaped and configured for movement (preferably rotational) relative to the hull and the water jet outlet nozzle between (a) an operative condition presented in the water jet flow path exiting the water jet nozzle to deflect the water jet sufficiently to be able to cause the watercraft to travel through water in a reverse direction, and (b) an inoperative condition where it is not in the water jet flow path.

46. A control mechanism as claimed in claim 45 wherein the control mechanism also comprising: a. a thrust vectoring nozzle to locate external of the hull adjacent the waterjet outlet nozzle and having an inlet to receive water from the water jet outlet nozzle and a passage to an outlet of the thrust vectoring nozzle the outlet able to re-direct the waterjet leaving the hull, b. a tiller stock coupled to and projecting upwardly from the thrust vectoring nozzle, and c. a tiller coupled to the tiller stock to allow a person to manually move the tiller for controlling the direction of the waterjet leaving the watercraft.

47.-61. (canceled)

Description

BRIEF DESCRIPTION OF THE FIGURES

[0186] FIG. 1 is a perspective view of a first example of a control mechanism engaged to a transom of a hull of a watercraft,

[0187] FIG. 2 is an end view looking onto a part of the stern of a watercraft of the first example,

[0188] FIG. 3 is an alternative perspective view of FIG. 1,

[0189] FIG. 4 is a side view of a watercraft with a jet propulsion unit and control mechanism of the first example,

[0190] FIG. 5 is a side view of the control mechanism and water jet outlet nozzle of a jet propulsion unit of the first example,

[0191] FIG. 6 is a perspective view of a mechanism and a water jet outlet nozzle of a jet propulsion unit of the first example,

[0192] FIGS. 7a-c show the control mechanism of the first example in different angles of rotation,

[0193] FIGS. 8a-c show a plan view of a control mechanism of the first example in different angles of rotation,

[0194] FIG. 9 is a plan view of a control mechanism of the first example,

[0195] FIG. 10 is a sectional view through section 8a of FIG. 9,

[0196] FIG. 11 is an end view of a control mechanism of the first example,

[0197] FIG. 12 is side view of a control mechanism of the first example,

[0198] FIG. 13 is a plan view of a control mechanism of the first example,

[0199] FIG. 14 is an end view of a control mechanism of the first example,

[0200] FIG. 15 is an exploded component view of a control mechanism of the first example,

[0201] FIG. 16 is a rear view of part of a watercraft of the present invention showing a second example of a control mechanism that has an offset tiller arrangement.

[0202] FIG. 17 is a perspective view of FIG. 16,

[0203] FIG. 18 is alternative perspective view of FIG. 16,

[0204] FIG. 19A-F show a range of motion of the tiller and the thrust vectoring nozzle in the second example of the invention,

[0205] FIG. 20 shows a third example of a control mechanism of the present invention which allows for control of the direction of forward movement of the watercraft and also a reversing of the watercraft using a reverse bucket configuration,

[0206] FIG. 21 is a bottom perspective view of the third example,

[0207] FIG. 22 is a perspective view of part of the third example with the bucket in a non-active condition or raised position,

[0208] FIG. 23 is a view from the stern of the arrangement of the third example with the bucket in its raised position,

[0209] FIG. 24 is a stern view of the arrangement of the third example with the bucket in the lowered or reverse mode condition,

[0210] FIG. 25 is an alternative perspective view,

[0211] FIG. 26 is a plan view of the third example,

[0212] FIG. 27 is a view of the third example in the opposite direction to FIG. 23,

[0213] FIG. 28 is a view of the third example showing the bucket in both the up and down positions,

[0214] FIG. 29 is a view from the rear of the arrangement of the third example with the bucket in the down position,

[0215] FIG. 30 is a perspective view of part of the arrangement of the third example,

[0216] FIG. 31 is a perspective view of part of the arrangement of the third example,

[0217] FIG. 32 is a plan view of the tiller and reverse handle,

[0218] FIG. 33 is a bottom view of the parts shown in FIG. 32,

[0219] FIG. 34a is a sectional view through the upper part of the arrangement of the third example,

[0220] FIG. 34b is a bottom perspective view of the upper part of the arrangement of the third example,

[0221] FIG. 35 is a closeup view of area A of FIG. 34a,

[0222] FIG. 36 is a view of the lower part of the arrangement of the third example,

[0223] FIG. 37 is a closeup perspective view of the linkage mechanism for the bucket,

[0224] FIG. 38 is a closeup of region B of FIG. 36,

[0225] FIG. 39 shows a sectional view through the lower part of the arrangement of the third example, shown through section XX of FIG. 36,

[0226] FIG. 40 is a closeup view of detail C of FIG. 39.

DETAILED DESCRIPTION

[0227] The invention relates to or is for a watercraft that has a hull 6 and a jet propulsion unit 111 as seen for example in FIG. 4. The watercraft may for example be a boat, dingy, tender, pontoon, or the like and is preferably less than 5 m long. The watercraft is preferably less than 4 m long. The watercraft is preferably less than 3.7 m long. The watercraft preferably has no cabin or centre console.

[0228] With reference to the example seen in FIG. 4, the watercraft may be configured or configurable with a jet propulsion unit 111 having a water jet outlet nozzle 5 and a water jet inlet 112 and impeller 114 to act as a water pump as part of the jet propulsion unit. The jet propulsion unit is located near the stern of the watercraft. The unit may also incorporate an electric motor to power the impeller.

[0229] The jet propulsion unit 111 is able to draw water via the inlet 112 through the hull and deliver water out of the hull through an opening of the water jet outlet nozzle 5. In a preferred form the water jet outlet nozzle 5 is presented at and secured to the transom 100 of the hull 6 of the watercraft. The water jet outlet nozzle 5 is hence preferably presented at the stern region of the hull 6 and preferably at a lower region of the hull. The water jet outlet nozzle 5 may for example, when the watercraft is in the water, be located under the water level. Alternatively, the water jet outlet nozzle 5 may be located at or slightly above water level.

[0230] The water jet outlet nozzle 5 projects the flow of water leaving the jet propulsion unit 111 in a fixed direction via an outlet of the water jet outlet nozzle 5. This water flow path is preferably in a direction parallel to and on the centreline of the watercraft. It projects the flow of water out the stern and away from the watercraft in order to propel the watercraft forward. This flow direction is desirably controlled and able to be varied in order to steer the watercraft when traveling forward. It may also be controlled in order to cause the watercraft to reverse.

[0231] A first example of a control mechanism will be described with reference to FIGS. 1-15. A second example will be described with reference to FIGS. 16-19. A third example will be described with reference to FIGS. 20-40. The control mechanism of the third example includes an ability for the thrust of the water jet to be reversed in a manner to cause the watercraft to be able to reverse. Examples one and two do not have this function.

[0232] Reference will first be made to the first example.

[0233] Associated with the hull is a control mechanism 500. It may also be through of an interchangeably describes as control system. The control mechanism is preferably pivotally mounted relative to the hull 6 and preferably at the stern such as to the transom 100 of the hull 6. The axis of rotation of the control mechanism is preferably about axis A as seen in FIGS. 4 and 5 or may be at least in part parallel to axis A. Axis A generally extends in an up and down direction which may be vertical or acute to vertical. Axis A is preferably parallel the notional vertical plane of the watercraft passing through the centreline of the watercraft. In the preferred form the control mechanism is mounted in a gudgeon and pintle style manner to the hull.

[0234] The control mechanism as seen in FIGS. 1-15 comprises of a thrust vectoring control member that may in a preferred form be a thrust vectoring nozzle 3 that is located externally of the hull. It presents control surface of surfaces that can receive water from the water jet. It is preferably presented in the direct flow path of the wate jet leaving the water outlet nozzle. In some forms the vectoring control member may not be a nozzle. It may be a plate acting like a rudder.

[0235] The thrust vectoring nozzle 3 has a stock 1 attached to it that projects upwardly from the thrust vectoring nozzle 3 to a tiller 11. The stock 1 is able to control the rotation of the thrust vectoring nozzle 3 about the axis A and the tiller 11 is able to control the rotation of the stock 1 and hence also the thrust vectoring nozzle about the axis A. The tiller 11 may include a handle 120 at where a person is able to conveniently grasp the tiller 11 for control of movement of the tiller 11. The tiller 11 may be directly coupled to the stock 1 as seen in the first example of the control mechanism as seen in FIGS. 1 to 15 or it may be indirectly coupled to the stock 11 as seen in the second example of the control mechanism as seen in FIGS. 16-19.

[0236] The tiller 11 may be coupled to a stock in a fixed manner so that its angle to the stock 1 cannot change relative to the stock or it may be coupled to the stock 1 in an articulatable manner so that the tiller 11 can be moved between a use condition that is at or near horizontal connected to the stock and a tilted up condition that is more vertical. The tiller 11 may or may also be uncoupled from the stock 1 and may be removed from the stock 1 for storage purposes or to move it out of the way when desired.

[0237] The control mechanism is preferably mounted to the hull using (i) a mounting bracket 2 that is secured to for example the transom 100 and with which the stock is a journaled for rotation about axis A, and (ii) pivot pins 13 and 14 of for example the water jet outlet nozzle 5 by which the stock and/or the thrust vectoring nozzle 3 is pivotally mounted.

[0238] Many other forms of mounting of the control mechanism relative to the hull in a pivotal manner will be envisaged by a person skilled in the art. In some forms it is envisaged that the stock is sufficiently supported by the water jet outlet nozzle and does not require a gudgeon and pintle style support.

[0239] The thrust vectoring nozzle 3 includes an inlet 200 and an outlet 201. The inlet 200 is presented to be able to receive the jet of water exiting the water jet outlet nozzle 5. The thrust vectoring nozzle 3 includes a passage 202 between the inlet 200 and the outlet 201 of the thrust vectoring nozzle 3. The passage 202 allows for the water from the water jet outlet nozzle 5 to be ducted through the thrust vectoring nozzle 3 and exit the thrust vectoring nozzle 3 through the outlet 201. Because the thrust vectoring nozzle 3 is able to pivot about the axis A, controlled by the tiller, the direction of the water jet leaving the watercraft is able to altered. This allows for a control over the direction of travel of the watercraft to be exercised by the control mechanism that is able to be controlled by the skipper of the watercraft. The thrust vectoring nozzle 3 is hence able to redirect the water jet leaving the hull so that the direction of travel of the watercraft can be altered.

[0240] In a preferred form the tiller 11 is directly coupled to the stock 1 as seen in the first example. An alternative and second example will now be described where the tiller may be coupled to the stock in a manner creating a mechanical advantage or a gear ratio between the two. This is for example, seen in FIGS. 16-19.

[0241] In FIG. 16-19 there is shown an offset tiller configuration. A tiller 1011 is mounted relative to the hull for pivoting around axis B. The tiller 1011 may be mounted or secured or be part of an axle or rod or shaft or the like (herein after axle 1221) that is mounted in a bush or bearing or journaled manner at 1214. The journal or bearing so supporting the axle 221 is preferably held by or is part of the mounting bracket 1002 that also is provided for mounting the stock 1001 to the hull. The stock 1001 in the example shown in FIG. 16-19 still rotates about its axis A which may preferably be located on the centre line of the watercraft. The axis B may be offset and is preferably parallel to axis A. A coupling 1218 may extend between a lever arm 1310 of the axle 1221 and a lever arm 1311 at the end 1272 of the stock 1001. The coupler 1218 is able to pivot relative to the lever arms and transfer forces both push and pull between the lever arms. The coupling 1218 may be mounted to the lever arms at its respective ends at an equal distance from their respective axes A and B or at an unequal distance with respect to their axes A and B. When uneven, a ratio other than 1:1 is established between the tiller rotation and the trust vectoring nozzle. If the distance of the lever arm at its distal ends with respective levers from the respective axes is the same, the ratio will be 1:1.

[0242] In some forms the lever arms may include an array 1410 of 4 mounting positions for example, the lever arm 1311 as shown in FIG. 19D. Likewise, the lever arm 1310 may include an array of mounting positions for the coupler 1218 so as to allow for the ratio of movement between the tiller and the stock to be easily varied as desired.

[0243] With reference to FIGS. 20-40, a third example of the present invention is described. The arrangement shown in these figures allow for both steering control and reverse control of the watercraft to be exercised by this example of the present invention. In the third example a water jet deflector 2600 is utilised for deflecting the water jet leaving the hull in a way sufficient to allow for the watercraft to travel in reverse. The water jet deflector 2600 is often also known as a reverse bucket. Reverse buckets are common on jet boats and jet skis in order to allow for such watercraft to be able to reverse. In an operative condition where the bucket is for example in the down position as seen in FIGS. 20, 21, 24 and 27, the water jet can exit via ports or openings 2601a and 2601b through these openings to direct the water jet or at least parts of it in a direction towards the bow of the watercraft. This change in direction of the flow of the water jet will cause the watercraft to start to travel in reverse. In effect the water jet deflector causes the water jet exiting the hull in a direction away from the bow of the vessel to turn more than 270 degrees so that the water flow from the jet starts to travel towards the bow of the watercraft.

[0244] The bucket is preferably mounted for rotation about an axis YY. This allows for the bucket to move between an inoperative position as seen in FIG. 22 where it does not cause the jet flow to change direction to an operative condition as seen for example in FIG. 20 where the bucket is presented in the flow of the jet to cause the watercraft to travel in reverse.

[0245] The third example may be provided as a unit able to be secured to the stern or transom of the hull of a watercraft. As can be seen in FIG. 22, a transom mounting plate 2602 may be provided for securing the arrangement to the transom of the watercraft and a baseplate 2603 may be provided which may be utilised for supporting the axles 2604 that define the axis of rotation YY, for the waterjet deflector 2600. The baseplate 2603 may also be secured to a part of the watercraft or may project beyond the transom of the watercraft and present a substantially flat or smooth base surface to allow it to plane over the surface of a body of water in a hydrodynamic manner. The function of the baseplate 2603 also helps shape the water jet flow when the water jet deflector 2600 is in its active condition (eg its down position). It can be seen from the figures that the water jet deflector 2600 can sit on or in close proximity to the baseplate 2603 so that together, they can shape the flow for reversing the watercraft.

[0246] In the third example a stock 2001 is also utilised. The stock comprises of two components namely the tiller stock 2001a and the reverse stock 2001b. The tiller stock 2001a is akin to the stock 1 or 1001 described with reference to the first and second examples and is provided for controlling the direction of the vectoring nozzle 2003 that is mounted for rotation about an axis coaxial to the stock. The vectoring nozzle 2003 may be secured for rotation at its bottom region by an axle 2605 to the baseplate 2603. At an upper region it may be supported by a bracket 2606 that may depend from the transom mounting plate 2602. In a preferred form the tiller stock 2001a is at least partially sleeved by the reverse stock 2001b. The reverse stock and the vectoring stock are hence mounted for rotation, coaxial each other, and relative to the hull of the watercraft. The tiller stock 2001a may be directly connected, at its upper end to a tiller or indirectly coupled to a tiller 2011, in a manner offset and akin to the configuration of the second example.

[0247] A mounting bracket 2002 may be used for holding the stocks at their upper end relative to the hull of the vessel and for mounting other components as will herein be described.

[0248] As per the second example, the third example as seen in FIG. 33, may have the tiller mounted relative to the mounting bracket 2002 using an axle 2221 that defines an axis of rotation of the tiller relative to the mounting bracket 2002 and hence the hull. A coupling 2218 may be utilised for coupling the lever arms 2310 and 2311 together and thereby creating a linkage between the tiller and the tiller stock. Rotation of the tiller will hence therefore cause rotation of the tiller stock. The mechanical advantage may be adjusted by an array of mounting positions 2410 on one or both of the lever arms 2310 and 2311. Rotation of the tiller can hence cause the vectoring nozzle 2003 to rotate and thereby cause the direction of forward travel of the watercraft to change. This is akin to the arrangement of the second example hereinbefore described. The vectoring nozzle 2003 may be directly coupled at the end of and to the tiller stock 2001a or alternatively a lever arm 2630 may be provided at the end of the tiller stock that by way of a coupling 2631 may be connected in an appropriate location to the vectoring nozzle 2003.

[0249] The reverse stock 2001b is also provided in a manner for it to rotate. Its rotation is coaxial the tiller stock. Its rotation is controlled by a reverse handle 2607 that is mounted to the mounting bracket 2002 using an axle 2608. The handle can be rotated thereby causing the handle lever arm 2609 to rotate. The handle lever arm is connected to a reverse stock lever arm 2610 by a coupling 2611. Hence a rotation of the reverse handle 2607 will cause, by virtue of the connection hereinbefore described, a rotation of the reverse stock.

[0250] The reverse handle 2607 preferably has two rotational end positions. A first rotational end position corresponds to the water jet deflector 2600 being in an inoperative condition such as in an up position seen in FIG. 22 and a second rotational end position corresponding to the water jet deflector being in an operative condition such as a down position as shown in FIGS. 20 and 24 for example.

[0251] A user is hence able to rotate the handle between its end positions to control the position of the water jet deflector and thereby cause a forward travelling watercraft to slow down and to start travelling in reverse once the water jet deflector is in its operative position. Being conveniently provided mounted by the mounting bracket 2, both the tiller 2011 and the reverse handle 2607 are provided in a convenient manner for use by an operator of the watercraft. In a preferred form the reverse handle is manually operable by the user. However it is envisaged that actuation of the reverse stock may also occur by way of an electrical actuator or a hydraulic automatic actuator. Control of such actuators may be from the tiller, such as at a location at or near its free distal end.

[0252] The rotation of the reverse stock 2001b is able to be translated to rotation of the water jet deflector about its axis YY via a reverse control linkage mechanism. The reverse control linkage mechanism comprises a reverse stock lever arm 2615 that projects from the reverse stock 2001b as for example seen in FIG. 30. The arm 2615 at or towards its distal end 2616 is connected to a cam mechanism 2617 that is positioned at one side of the water jet deflector 2600 and that is connected to the water jet deflector 2600 at a rotatable connection 2620 that defines an axis of rotation parallel to axis YY but is offset from axis YY. This allows for a torque to be applied to the water jet deflector to cause it to rotate about the axis YY for causing the water jet deflector to move between its operative and inoperative conditions.

[0253] The cam mechanism 2617 may include a 4-bar-chain style connection in order to allow for the rotation of the arm 2615 about the axis of the stock 2001 to translate to rotation of the water jet deflector about its axis YY, that may be substantially perpendicular or in a plane perpendicular to the stock axis.

[0254] The reverse stock control swing arm 2615 is preferably connected to an over length pin 2636 that allows for vertical travel relative to a slotted pin 2637 that allows for horizontal travel. With reference to FIG. 35 which is a closeup view of region A of FIG. 34a, additional components described includes a reverse stock and a tiller stock connection with bush 2641. The configuration as shown will facilitate the coaxial positioning and relative rotation of the tiller stock and the reverse stock with each other and relative to the hull of the watercraft.

[0255] The lower end of the stock may be supported to or by the transom mounting plate 2602 using the bracket 2606 that, in a journaled or bearing or bush mounted manner, may rotationally support both of the tiller stock and reverse stock at region 2632 as seen in FIG. 40. A plane bush bearing 2633 may be utilised.

[0256] The third example of the present invention hence provides a means for controlling both the direction of the water jet leaving the watercraft for both steering of the watercraft whilst travelling in a forward direction and for causing the water jet to change direction sufficiently to allow for the watercraft to be reversed. The mechanism for reverse control is conveniently incorporated with a mechanism for the tiller control of the vectoring nozzle. The third example and as herein described with reference to the drawings is able to be configured for convenient retrofitting to the watercraft as a unit. To facilitate this option the angle of the transom mounting plate and the baseplate is able to be varied by virtue of a hinged connection 2647 and an ability for the bracket 2648a and 2648b to adapt to a range of angular positions between the transom mounting plate and the baseplate and be thereby set. A slotted connection region 2649 of the bracket may be used for facilitating such adjustability. This allows for the unit as shown in for example FIG. 20 to be fitted to watercraft of different angled transoms. Some watercraft may have a substantially vertical transom surface whereas other watercraft may have more acute angled transom surfaces. The hinged connection 2647 between the transom mounting plate and the baseplate allows for the angle of the baseplate to be appropriately set relative to the transom mounting plate, the transom and hence the hull of the watercraft. The angle of the baseplate 2603 is preferably positioned for effective hydrodynamic operation in concert with the hull of the watercraft.

[0257] The length of the stock 2001 may also able to be adjusted for differing transoms of different watercraft. Some watercraft may have a very high transom whereas others may have a low transom or a transom with a cut-out. The length of the stock may be conveniently adjusted by trimming it for setting at an appropriate height so that the distance between the mounting bracket 2002 and the vectoring nozzle 2003 is able to be selected appropriately for the transom to which the unit is to be mounted. In some configurations the stock, on or both of the tiller stock and reverse stock may be telescopic so as to provide another means of adjusting the length of the stock to accommodate different transoms of different watercraft.

[0258] The stock, the tiller stock and reverse stock are each of a straight elongate nature and their axis of rotation is about an axis in the elongate direction. They are preferably tubular. The tiller stock is preferably positioned inside the reverse stock and may be rod shaped.

[0259] In the preferred form any one of the control mechanisms are able to be retrofitted to a watercraft. Indeed, the jet propulsion unit may also be able to be retrofitted to a watercraft that is traditionally powered by an outboard motor or by manual power such as oars.

[0260] With reference to the FIG. 4 example but equally applicable to the other examples, the jet propulsion unit 111 is preferably powered by an electric motor 113 which in turn is powered by a source of electric energy such as an electric energy cell or battery 230. The electric motor may be of a kind known as a brushless motor. It may be watercooled. The electrical cables between the battery and the motor may be watercooled also.

[0261] The battery 230 is preferably mounted in a secure location to or in the hull 6 of the watercraft. In the preferred form the jet propulsion unit 111 is powered by an electric motor 113 or motors to rotate the impeller 114 and to thereby cause the watercraft, when in the water, to be propelled forward. The electric motor may be directly coupled by way of a shaft to the impeller 114. The axis of rotation the electric motor is preferably coaxial the axis of rotation of the impeller 114.

[0262] The watercraft may carry solar panels for the purposes of re-charging the electric battery.

[0263] As seen in FIGS. 17 and 18 as an example, the tiller 1011 may also be provided with a throttle control 1225 for allowing a user, at the handle, to control the speed of the impeller and hence the speed of the watercraft. The throttle control in this example may be a lever throttle control that can be operated by, for example, the thumb of a user. This may also be applied to the control mechanism of the other examples and for example as seen in FIG. 1, the control mechanism may also include controller 131 to control the electric motor 113. The controller 131 may control the speed of the electric motor. The controller 131 may be mounted to or be part of the tiller 11. Alternatively, the controller 131 may be located remote from the tiller. In the preferred form the electric motor controller 131 may be a throttle that is part of the handle 120 of the tiller. Alternatively, the controller may be a lever that may be able to be adjusted by a user.

[0264] The watercraft may also include an electric energy monitor that may display, for example, the current draw and voltage of the battery in real time. Such display may be provided at the region 130 on the tiller which is a convenient location for a user to be able to view battery and/or electric motor performance information.

[0265] An alarm may be included that may warn the user of undesirable battery and/or electric motor conditions. The alarm may activate when for example the battery voltage reaches a certain minimum threshold or if the battery or motor temperature exceeds a certain maximum threshold. The alarm may be incorporated into or as part of the control mechanism.

[0266] The or another electric controller may also be provided to automatically adjust the operation of the electric motor such as for example when the voltage drops below a certain minimum threshold the controller may reduce motor speed.