WO1988007469A1 - Boat launching equipment - Google Patents

Abstract

Launching equipment includes one or more wheels (18) which can be attached to the stern of a boat and may be used in a position in which they protrude below the boat so that the stern can run over the ground when the boat is out of the water. The wheel(s) (18) may be raised above the level of the boat bottom when not in use or may be mounted on a frame (16) which can be used off the boat for transporting an outboard motor or other articles. A trim tab may be connected to the wheel (18) so that when the wheel (18) is raised the trim tab is lowered to a working position and when the wheel (18) is lowered the trim tab is raised out of the way. A handle for use with the wheel (18) can be removed and used as a boarding ladder. A loop track can be used in place of the wheel (18) and may be disposed to act as a trim tab.

Description

  
 



   BOAT LAUNCHING EQUIPMENT
 This   invention    relates to boat launching equipment and is applicable particularly, but not exclusively, to launching from land and recovery from the water of inflatable dinghies. Such dinghies may have a hard rigid transom at the stern, to which outboard motors are frequently clamped. Alternatively, inflatable dinghies may have an inflated, relatively soft structure across the stern, with moulded-on brackets to which a frame may be attached to hold the outboard motor.



   It is well known to provide wheels or rollers which can be attached to the stern of a boat, so that it can be moved over land more easily than by carrying it. In one example an arm carrying a wheel is easily attachable to a special bracket fastened to the boat, and pivotable to a raised position when the boat is afloat, to avoid drag on the boat due to the necessity of the wheels to protrude below the bottom of the boat. The wheel is retained in the ground-engaging and raised positions by a removable pin passing through registering apertures in the arm and the bracket. Such an arrangement is difficult to operate and in the raised position the wheel or wheels obstruct access across the stern of the boat and constitute a protuberance likely to foul any low line under which the boat has to pass.



   It is also well known to provide a trolley for use with a boat, on which trolley the outboard motor can be wheeled to and from the boat. Such a trolley is shown in French Patent Specification 79 00 020 (Publi  cation No. 2 445 787). It is of course also common to use a separate hand-truck to carry gear and stores to the launching point of the boat.



   If one of the above-described trolleys or trucks is used in the launch of a boat, it either has to be returned to safe keeping before the journey, or carried on the boat, where it is an encumbrance, if needed at the other end of the journey. Furthermore, separate launching equipment and a trolley or truck entails an unnecessary duplication of wheels or rollers.



   It is an object of the present invention to overcome at least some of these disadvantages.



   Therefore, in accordance with the present invention, there is provided boat launching equipment, for attachment to a boat, including a wheel, which when the equipment is mounted on the boat protrudes below the bottom of the boat to engage the ground while supporting the boat when the boat is partly or entirely unsupported by water, the wheel being mounted on retraction means whereby the wheel may be lowered to the ground-engaging position or raised to an upper, retracted position when the boat is afloat, characterised in that the wheel is positioned entirely between the levels of the bottom and the top of the stern of the boat, when the wheel is in the upper positon and/or in that the equipment includes an automatic latch or over-centre arrangement to hold the wheel in said ground-engaging position.



   In accordance with a further aspect of this invention, the boat launching equipment is characterised in that the equipment includes a frame, on which both wheels are mounted, optionally releasable attachment means for  securing the frame to the stern of the boat, and load carrying means, whereby the equipment may be released from the boat and used to transport a load, with the wheels running along the ground and at least partly supporting the weight of the load.



   When a hard sterned inflatable or rigid dinghy type is being propelled by an outboard motor, there is often an excessive tendency for the stern to be depressed in the water or 'squat' and for the bow to lift.



   In accordance with a still further aspect of the invention, theme is provided boat launching equipment, characterised by a trim tab associated with the retraction means so that when the wheel is in the ground-engaging position, the trim tab will be above at least the lower part of the wheel so as to be clear of the ground, and when the wheel is in the said upper position the trim tab is held at an inclined working position within the water to generate an upwards thrust on the stern of the boat when it moves forwards.



   In accordance with a yet further aspect of the present invention, for use on soft ground, part of the equipment to engage the ground may be in the form of a loop track mounted on two or more wheels or rollers.



  Preferably, a lower part of the track may be arranged to act as a trim tab.  



   Various embodiments of the invention are described, by way of example only, with reference to the accompanying drawings, in which:
 Figure 1 is a perspective rear view of an inflatable dinghy fitted with boat launching equipment according to the invention,
 Figure 2 is a perspective view of the boat
 launching equipment shown in Figure 1,

   removed from the dinghy,
 Figure 3 is a perspective view of an alternative use to Figure 2,
 Figure 4 is a part section in a longitudinal plane through the stern of the inflatable dinghy shown in Figure 1,
 Figure 5 shows an alternative to Figure 4,
 Figure 6 shows another alternative to Figures 3 and 4,
 Figures 7 and 8 show different positions of an alternative to Figure 4,
 Figure 9 shows a further alternative to Figure 4,
 Figures 10 and 11 are side elevations of one form of boat launching equipment according to the invention in different working positions,
 Figure 12 is a rear elevation of the equipment shown in Figure 11,  
 Figure 13 is a perspective view of part of an inflatable dinghy of different construction from Figure 1,

   fitted with boat launching equipment according to the invention,
 Figures 14 and 15 are perspective views of the boat launching equipment of Figure 13 removed from the dinghy, in different load-carrying dispositions, and
 Figure 16 is a side elevation of another embodiment of the invention shown in a load-carrying disposition.



   In the drawings, items performing the same function are given the same reference numerals.



   Referring first to Figures 1 to 6, Figures 1, 2 and 3 show three main roles of boat launching equipment according to the invention. An inflatable dinghy 10 has a bow 11, stern 12 and rigid transom 13 to which an outboard motor 14 is fastened by clamps 15.



   A frame 16 in the form of a letter H is attached to the transom 13 by means of two hand wheel screws 17 situated one at the centre of each side of the frame 16 and engaging in captive nuts secured to the inner side of the transom 13. Any releasable device such as a D zus fastener, toggle or lever screws may alternatively be used. Attached to the base of the frame 16 are a pair of wheels 18 which may be fixed, demountable, adjustable for height, retractable or any combination of these.



   A pad 19 is rigidly fastened to one side of the frame 16, with its top slightly above the top of the transom 13. The dinghy 10 may be removed from the water by lifting and pulling on a loop or handle on the bow  11 and drawing the dinghy up a slipway or beach with the stern 12 carried by the wheels 18 running along the grpund, the equipment thus being used in its first role.



   The motor 14 is   unclamped    from the transom 13, lifted slightly and moved sideways until the clamps 15 are over the pad 19. The frame 16 is released from the transom 13 and the motor 14 can be wheeled away from the dinghy 10, as shown in Figure 3, with the equipment performing its second role. For this purpose a detachable centre-hinged handle 20 provided with a locking device 20a may be fastened to the frame 16 by the screws 17 or otherwise. The handle 20 may be folded down to act as a steady for the frame 16, as shown in Figure 2, which also shows the launching equipment used in its third role, as a load carrier. In this configuration, the frame 16 is disposed in a generally horizontal position and a wooden or plastic pallet or board 21 is affixed thereon by the screws 17. Fuel cans, provisions or the like may be transported on the load carrier.

 

   The motor 14 may be returned to the dinghy 10, clamped thereto, and the dinghy launched by reversing the procedure described above.



   Figure 4 shows the wheel 18 mounted on a trailing arm 22 to the frame 16 by bolts and a plurality of holes 23 in the frame 16, whereby the degree of protrusion of the wheel 18 below the stern 12 may be adjusted.



   In Figure 5 the wheel 18 is mounted on a radius arm 24 to the trailing arm 22, so that the wheel 18 may be fastened in a lower position for use on the ground, or held in an upper position where the wheel 18 is above the bottom of the stern 12, so as to avoid drag on the  dinghy due to the protrusion of the wheel 18 into the stream of water below the dinghy, when moving.



   In Figure 6, the radius arm 24 is pivoted onto the frame 16, through approximately 180 degrees, from a lower position in which the wheel 18 is wholly below the stern 12 and forward of the transom 13. This gives good ground clearance of the bottom of the dinghy and enables a greater percentage of the dinghy weight to be carried on the wheels 18, and a mounted outboard motor to have a greater counterbalancing effect on the weight of the boat. A stop 25 is mounted on a strut 26 rigidly attached to the radius arm 24, to limit rotation of the arm 24 in one direction, by bearing against the underside of the dinghy 10.



   By rotating the arm 24 anti-clockwise, the wheel 18 is located in its highest position, fully above the underside of the dinghy 10. When the latter is to be removed from the water, the arm 24 is rotated until the stop 25 digs into the ground, when a backward push on the bows 11 will cause the wheel 18 to swing relatively forward and beneath the dinghy 10, in which position it is maintained by an overcentre effect.



   If desired the wheels 18 may be joined by a rod or axle; and can be arranged to be raised and lowered by, for example, a sliding mechanism rather than on radius arms 24. They may be held in the upper or lower positions by spring force or by a latch mechanism.



   Instead of being to one side of the frame 16, the motor mounting pad 19 may be central and the motor 14 left and operated thereon, part of the transom 13 being cut away to accommodate the pad 19. Alternatively, the  mounting pad may take the form of a partial or complete false transom which is in use juxtaposed against the original transom; or, particularly in the case of a new vessel the pad 19 might take the form of an actual transom.



   In place of the pallet 21 a pair of forks, similar to those used on fork lift trucks, may be attached to the frame 16, in which case a rigid handle 20 is used to raise any load on the forks by the operator bearing down on the handle.



   Referring now to the embodiments shown in Figures 7, 8 and 9, when a watercraft is being propelled by an outboard motor, where the line of thrust of the propeller is below the bottom of the craft, the stern 12 is depressed in the water and the bows 11 lift. This causes excessive drag, reducing speed and wasting fuel. It also generates an excessive stern wave causing much nuisance to moored craft which are subjected to sudden violent rolling.



   This depression of the stern 12 can be reduced by trim tabs 27 which are well known per se but they normally tend to catch the ground when the dinghy is not floating.



   The radius arm 24 is rotated on the trailing arm 22 by a bell-crank hand lever 28 pivotted on a bracket 29 on the frame 16. The lever 28 is connected to the upper part of the radius arm 24 by a long link 29, the lower end of which is connected in turn by a short link 30 to a bracket 31, extending from the plane of the trim tab 27 to axle or pivot at the centre of the wheel 18.  



   The proportions of the lever 28, radius arm 24, links 29,30 and bracket 31 are such that, as shown in
Figure 8, when the lever 28 is held upright by a catch 32 on the frame 16, the wheel 18 is raised to be above, or largely above, the bottom of the stern 12, and the trim tab 27 is locked at an inclined disposition where it rises towards the bows 11 of the dinghy 10. The angle of inclination thereof is chosen to give a good hydrodynamic lift and low drag.



   In Figure 7, the wheel 18 is shown in the lowered position for transporting the dinghy 10, the trim tab 27 now being rotated about the wheel axle to a position in which the trim tab 27 is largely above the bottom of the stern 12. The lower part of the lever 28 and the long link 29 are then aligned so that the weight on the wheel 18 locks the system, the catch 32 being released.



   The link 30 may be in the form of a screwed rod or otherwise adjustable, whereby the angle of incidence of the trim tab 27 may be adjusted.



   In Figure 9 the functions of the wheel and the trim tab are combined by use of loop track 33 which may be of articulated or flexible elastomeric construction.



  The track 33 is constrained by four wheels 34 mounted on a lozenge-shaped frame 35. The track 33 exerts a lower ground pressure than the wheel 18 of previous embodiments and is therefore better for running on sand.



   The lower length 36 of the track 33 is disposed at an inclination and position below the bottom of the stern 12 at which the under surface of the length 36 will act as a trim tab and generate lift. The frame  35 may be adjustably pivoted to the frame 12, so as to set the incidence angle of the length 36 of the track 33, and to allow the frame 12 and track 33 to be retracted.



   Figure 10, 11 and 12 show an embodiment of the invention which is particularly compact and easy to operate, even when the boat is in motion. The bell-crank lever 28 is connected to the radius arm 24 by upper and lower generally aligned links 37,38 pivoted at their junction to a third crank-arm 39, and pivoted in turn to the lower part of the frame 16. The connection of the link 38 to the radius arm 24 is by a peg 40 engaged in a short slot 41 in the arm 24.



   In Figure 10 the wheel 18 is in the raised position reached by rotation of the lever 28 down onto the wheel 18 until a spring-loaded catch 42 engages an adjacent sharp corner of the lever 28.



   In Figure 11 the wheel 18 has been swung down and forwards by releasing the catch 42 and pulling up the lever 28 until the radius arm 24 reaches a stop 43.



  At this position a corner of the crank-arm 39 engages in a notch 44 in the end of the radius arm 24, which is thereby prevented from rotation away from the stop 43. However, the wheel 18 and the linkage can be released, to raise the wheel 18, the lever 28 is pushed away from the catch 42, which pulls the links 37,38 and thereby raises the peg 40 in the slot 41 to release the corner of the arm 39 from the notch 44 before the peg 40 starts to rotate the radius arm 24 on the frame 16. Automatic locking and unlocking in the ground-engaging position is thus provided simply by operation of the lever 28.  



   As particularly seen in Figure 12, there are two levers 28, one at each side of the dinghy 10, and joined by a shaft 45, so that the wheels 18 can be raised and lowered from either side of the motor 14 or the dinghy 10.



   Figures 13, 14 and 15 show an embodiment of the invention adapted to be used on the type of inflatable dinghy 10 which has an inflatable stern 12 instead of a rigid transom 13. In this type of stern 12 a pair of hard rubber or plastic fore-and-aft sockets 46 are provided at each side of the stern 12.



   The frame 16 for use with these sockets 46 is of bent tubular construction, having ends 47 to pass through the sockets 46 and be retained by spring clips 48, bends or bights 49 to fit around the inflated stern 12, arms 50 to hold the wheels 18 and channels 51 to hold the pad 19, on which the motor 14 is clamped.

 

   Figure 14 shows the frame 16 detached from the sockets 46 and rotated through a right angle until the pad 19 is horizontal, and the pallet 21 is secured to the frame 16, for example by swing latches. The handle 20 in this embodiment is formed with sockets 52 in whih the frame ends 47 are secured by the clips 48.



   Figure 15 shows the frame 16 in the same disposition as used on the dinghy 10, with the pad 19 vertical for transporting the motor 14.



   In alternative embodiments the equipment shown, for example, in Figs. 10, 11 and 12 may be mounted on a recessed lower transom, or on the forward end of a trunk mounted on the floor, of a rigid dinghy, a spring  loaded flap being pivotally mounted at the lower edge of the transom or trunk. When the wheel or wheels are retracted the flap is urged against an adjustable stop which maintains it at an optimum angle to act as a trim tab and also as a bottom closure panel. When the wheels are moved to their down, ground-engaging position the arrangement is such that the flap is pushed downwardly and forwardly by the wheel-carrying radius arms to allow projection of the wheel(s).



   Figure 16 shows the mechanism shown in Figures 10, 11 and 12 mounted on a handle 20 which is in the form of a tubular boarding ladder. The motor 14 is mounted on the pad 19 for transportation and the frame 16 is fastened to the handle 20 by the hand wheels 17. The lower parts of the handle 20, in Figure 16, are in the form of a semi-circle enabling the carrier to rest on the ground. A rung 53 of the ladder handle 20 supports the pallet 21, which is retained by screws 54 into the ends of the handle 20.

 

   When the handle 20 is not in use for transportation, it is detached from the frame 16, inverted and hooked on to the parent vessel with the semi-circular parts passing over the toerail, gunwale or bulwarks and with the pad 19 acting as a stand-off block against the topsides.



   In any of the above embodiments rollers or tracks can be substituted for wheels, if preferred.



   Clearly, the embodiments of multi-functional dinghy transporting equipment described above afford great savings in cost, component and storage space and compared with the use of separate vehicles, as well as being very convenient in use. 

Claims

CLAIMS:

1. Boat launching equipment, for attachment to a boat, including a wheel (18) which when the equipment is mounted on the boat protrudes below the bottom of the boat to engage the ground while supporting the boat when the boat is partly or entirely unsupported by water, the wheel being mounted on retraction means (24) whereby the wheel may be lowered to the ground-engaging position or raised to an upper, retracted position when the boat is afloat, characterised by the wheel (18) being positioned entirely between the levels of the bottom and the top of the stern of the boat, when the wheel (18) is in the upper position.

2. Boat launching equipment, for attachment to a boat, including a wheel (18) which when the equipment is mounted on the boat protrudes below the bottom of the boat to engage the ground while supporting the boat when the boat is partly or entirely unsupported by water, the wheel being mounted on retraction means (24) whereby the wheel may be lowered to the ground-engaging position or raised to any upper, retracted position when the boat is afloat, characterised in that the equipment includes an automatic latch (39,44) or over-centre arrangement to hold the wheel (18) in said ground-engaging position.

3. Boat launching equipment, as claimed in claim 2, and including a latch, characterised by a handle (28) movable in one direction to move the wheel (18) into the ground-engaging position and movable in the reverse of said one direction to move the wheel (18) to said upper position, the latch being releasable by movement of the handle in said reverse direction.

4. Boat launching equipment as claimed in claim 3, including a frame (16) to be fastened to the boat, the retraction means including an arm pivoted at one end to the frame and having at the other end an axle on which the wheel is revolvable, characterised in that the arm (24), the handle (28) and a latching arm (39) are pivoted to the frame (16) and interconnected by linkage such that the latching arm is moved into latching engagement during the final part of the movement of the wheel to the ground-engaging position, the linkage including a slack element (40,41) whereby the latching arm is moved out of latching engagement by movement of the arm before it starts to move the wheel from the ground-engaging position.

5. Boat launching equipment, as claimed in claim 4, characterised in that when in latching engagement, the latching arm is in abutment with part of said arm.

6. Boat launching equipment, as claimed in any of claims 3 to 5, characterised by two of said handles being interconnected and located one each side of, and remote from, the central longitudinal plane of the boat.

7. Boat launching equipment, for attachment to a boat, including a wheel (18) which when the equipment is mounted on the boat protrudes below the bottom of the boat to engage the ground while supporting the boat when the boat is partly or entirely unsupported by water, the wheel being mounted on retraction means (24) whereby the wheel may be lowered to the ground-engaging position or raised to an upper, retracted position when the boat is afloat, characterised by a trim tab (27) connected to the retraction means so that when the wheel is in the ground-engaging position, the trim tab will be above at least the lower part of the wheel so as to be clear of the ground, and when the wheel is in the said upper position the trim tab is held at an inclined working position within the water to generate an upwards thrust on the stern of the boat when the boat is moving forwards.

8. Boat launching equipment, as claimed in claim 7, characterised in that in said inclined working position the trim tab will be underneath the wheel.

9. Boat launching equipment, for attachment to a boat, which equipment protrudes at least partly below the bottom of the boat to engage the ground while supporting the boat when the boat is partly or entirely unsupported by water, characterised in that the part of the equipment to engage the ground is in the form of a loop track (33) mounted on two or more wheels or rollers.

10. Boat launching equipment, as claimed in claim 9, characterised by the wheels or rollers holding the track in a shape of which the lower part (36) provides a web inclined upwardly towards the bow of the boat, so that said plane acts as a trim tab when the boat is moving forwards.

11. Boat launching equipment, as claimed in claim l0, characterised in that said track is of adjustable inclination relative to the equipment, so as to allow regulation of the trim tab effect of said lower part and/or to allow retraction of the track.

12. Boat launching equipment, for attachment to a boat, including a pair of wheels which, when the equipment is mounted on the boat, protrude below the bottom of the boat to engage the ground while supporting the boat when the boat is partly or entirely unsupported by the water, characterised in that the equipment includes a frame (16) on which both wheels are mounted, optionally releasable attachment means (17) for securing the frame to the stern of the boat, and load carrying means (19,21), whereby the equipment may be released from the boat and used to transport a load, with the wheels running along the ground and at least partly supporting the weight of the load.

13. Boat launching equipment, as claimed in claim 12, characterised in that the load carrying means includes fixing means (19) to which an outboard motor (14) of the boat can be attached by the attachment mean usually used to attach the motor to the stern of the boat.

14. Boat launching equipment, as claimed- in claim 13, characterised in that the fixing means includes a flat pad to which the motor can be attached when removed from the boat and which is constituted by a partial or complete false transom which may be secured to the permanent transom of the boat or by a removable actual transom.

15. Boat launching equipment, as claimed in claim 13 or 14, characterised in that the load carrying means includes a board or pallet (21) on which an article can be placed to be transported.

16. Boat launching equipment, as claimed in claim 15, characterised in that the board or pallet is detachable from the equipment.

17. Boat launching equipment, as claimed in any of claims 12 to 16, characterised in that the frame (16) is adapted to be used in one disposition on the wheel for carrying the engine, and in another disposition, rotated through approximately a right angle about the wheel axis for carrying another article or the said article.

18. Boat launching equipment, as claimed in any one of claims 12 to 17, characterised in that a handle (20) is provided on the equipment, the handle being of adjustable inclination thereto.

19. Boat launching equipment, as claimed in claim 18, characterised in that the handle is inclinable to a location in which it acts as a stand or steady by engaging the ground.

20. Boat launching equipment, as claimed in any of claims 12 to 19, characterised in that a or the handle (20) of the equipment is in the form of a boarding ladder which may be attached to the boat after the wheel and any load has been removed therefrom.

21. Boat launching equipment, as claimed in any of claims 12 to 20, characterised in that the wheels are retractable from the ground-engaging position.

22. Boat launching equipment, as claimed in any of claims 1 to 8, characterised in that a plurality of said wheels are included.

23. Boat launching equipment, as claimed in any of claims 1 to 8 and 12 to 22, characterised in that a ground engaging roller is used in place of one or more of said wheels.

24. Boat launching equipment, as claimed in any of claims 1 to 8 and 12 to 22, characterised in that a ground engaging loop track is used in place of one or more of said wheels.