TITLE Outboard motor mounting clamp BACKGROUND Outboard motors suitable for use on smaller sized boats are often installed and removed each time such boats are used. Currently two conventional screw bolts are used for this fixing and removal operation, with the screws passing through a motor mounting clamp housing and bearing against the transom of the boat. These screw bolts are each manually turned by way of a small handle and tightened until a firm fit is achieved between the motor mounting clamp and the transom, or stern, of a boat. The time taken for this conventional method of fixing and removal of an outboard motor can amount to some minutes, and is mostly performed when a boat is on dry land such as on a sloping and often slippery boat launching ramp. During attachment or removal of the motor under these conditions, in order to gain adequate clearance for the propeller, the outboard motor body must be tilted somewhat forward and this can interfere with ready access to, and operation of, the screw bolts Because outboard motors normally require the use of both hands in carrying to and from a boat, and because of the sloping and often slippery nature of most boat launching ramps, personal accidents leading to injuries can and do occur.

Additionally when at sea, outboard motors are often clamped onto a holding bracket fixed to the stern rail of a yacht or motor launch. When the motor is required to be affixed to the tender of the yacht, such as a small dingy or inflatable craft riding tethered alongside, the motor must be first detached from a holding bracket and then lowered down to be fitted to the tender. Again because of the need to use both hands in this operation, the good seamanship code requiring always one hand for the ship cannot be complied with.

The time taken to affix or detach a mounted motor to a tender provides further opportunity for accidents such as capsize, especially where such a small craft may be rocking in response to passing boat wakes or ocean swells. A safety tether in the form of cordage is usually tied off between the motor and a fixing point on the boat to prevent the loss of an outboard motor overboard in the event that it may become accidentally detached from a boat during use.

PRIOR ART US Patent specification 4,524, 942 discloses an outboard motor mounting assembly in the form of an inverted U shape clamp on which the motor is mounted. The clamp includes a transom plate which is mounted on the inside of the transom.

US Patent specification 3,025, 028 discloses another form of supporting bracket for an outboard motor which is capable of supporting the motor in a variety of vertically adjustable positions.

US Patent specification 3,598, 348 discloses yet another form of clamp bracket for an outboard motor and has two inverted U-shaped clamp members connected by a pivot pin. The inside leg of each clamp member is resiliently biased towards an open position to facilitate mounting of the motor on transoms of varying thicknesses.

All of the above known systems require the use of a screw member to complete attachment of the motor to the transom and consequently all suffer from the disadvantages of being difficult to use particularly under adverse circumstances.

OBJECT OF THE INVENTION It is therefore an object of this invention to provide an improved clamp to enable an outboard motor to be quickly attached and detached from the transom of a boat and which will overcome or at least minimise the above disadvantages..

SUMMARY OF THE INVENTION In one preferred form the invention is a clamp to secure an outboard motor to the transom of a boat, said clamp comprising two spaced apart side plates pivotally connected to a bracket member which includes adjustment bolts by which the outboard motor can be removably attached to the bracket member, said side plates including off-centered cam faces and wherein the side plates can be pivoted to a locking position whereby the cam faces contact the transom and retain the outboard motor on the boat and can be pivoted to a release position to release the clamp from the transom and enable the outboard motor to be removed from the transom.

Preferably the clamp includes locking means to retain the clamp in its locking position.

Preferably the locking means comprises a spring loaded locking pin which is located on one of the two side plates, and which will engage in a correspondingly positioned hole in the bracket member when the clamp is in a locking position.

Preferably the adjustment bolts include means to retain the bolts in engagement with the bracket member.

Preferably at least a portion of the cam faces of the side plates is formed into saw tooth type serrations.

In another form the clamp to secure an outboard motor mounting bracket to the transom of a boat, includes: an elongated attachment member securable to the outboard motor mounting bracket, the attachment member having two ends each adapted to be guided between facing surfaces of two parallel spaced apart arms of a yoke member, the arms of the yoke member having noses which are formed to bear against the transom when the clamp is in an operative position, a shaft having a first and a second end, a bore formed in the yoke member through which the first end of the shaft can be passed a boss formed as part of the attachment member and having a bore to receive the shaft, means whereby the first end of the shaft can be passed into the bore of the attachment member when the shaft is maintained at a first angle of rotation to the boss and to engage in the bore of the attachment member when the shaft is rotated to a second angle of rotation, a handle member pivotally attachable to the second end of the shaft, said handle member having a cam face adapted to be brought to bear against the yoke upon pivoting

the handle from a rest position to an engaged position to tend to move the yoke towards the transom of the boat when the shaft is engaged in the bore of the attachment member, Preferably at least a portion of the circumferential surface of the shaft is formed with a screw type thread.

Preferably at least a part of the circumferential surface of the shaft has a longitudinal flat so formed that a first diameter through the shaft in the region of the flat is of less dimension than the dimension of a second diameter of the shaft at 90° from the first diameter.

Preferably the interior of the bore of the attachment member is provided with means to engage with the shaft when the shaft has been rotated to an engaged position.

Preferably the means within the bore of the attachment member to engage with the shaft comprises a screw type thread.

Preferably wherein an elastomeric means is positioned between the cam face of the handle member and the yoke and a cap is positioned between the elastomeric means and the cam face of the handle member.

Preferably the clamp includes means to releasably maintain the handle member in an engaged position.

BRIEF DESCRIPTION OF THE DRAWINGS Preferred forms of the invention will now be described with the aid of the accompanying drawings, wherein: Figure 1 is a diagrammatic view of the clamp of one form of the invention.

Figure 2 is a side view of the clamp illustrated in Figure 1, but also depicting a locked position of the clamp relative to an existing outboard motor mounting clamp housing, and including an illustration of a transom of a boat.

Figure 3 is a further side view of the clamp illustrated in Figures 1 and 2, but showing the clamp in an unlocked position.

Figure 4 illustrates an auxiliary wear plate that may be fitted to the transom.

Figure 5 illustrates a modified form of side arm for the clamp.

Figure 6 illustrates in a diagrammatic form a modified form of clamping means.

Figure 7 is an isometric view of a second embodiment of the clamp in a configuration where the handle is in a'vertical position'with the clamp positioned on the transom of a water craft but prior to securing the clamp to the transom.

Figure 8 is a view similar to that of Figure 7 but with the handle in a'horizontal' position at an intermediate step of securing the clamp to the transom.

Figure 9 is a further view similar to that of Figure 7 with the handle moved to a downward position with the clamp now secured to the transom.

Figure 10 is a plan view of the clamp illustrated in Figure 8.

Figure 11 is an end view of the clamp illustrated in Figure 10.

Figure 12 is a view to an enlarged scale of part of the clamp in an engaged position.

Figure 13 is a view similar to that of Figure 12 but showing the clamp in a disengaged position.

BEST MODE OF PERFORMING THE INVENTION The form, of the clamp illustrated in Figure 1 through 6 of the drawings is attachable to an existing motor mounting bracket 5 (see Figure 2). The clamp includes two side plates 1, each of which has a cam face 9 and a saw tooth surface 10. The two side

plates 1 are pivotally connected at 3 to an adjustment member 4 which includes two hand operated screw threaded adjustment bolts 6 on which lock nuts 6a are mounted.

The motor mounting bracket 5 (see Figures 2 and 3) is attached to the clamp by removing and discarding the conventional screw bolts from the legs of the bracket 5 and then passing the adjustment bolts 6 through the screw threaded holes 7 in the legs of the bracket 5. These bolts may be initially tensioned and then locked in position by lock nuts 6a in order to set the correct operating range of the clamp. Although not indicated in the drawings, means are preferably also provided to retain the adjustment bolts in the adjustment member. Such means can consist of a circlip, split pin or other means as will be apparent to those skilled in the art.

The cam faces 9 on the side plates have off-centered surfaces so that when the side plates 1 are rotated towards a closed position (see Figure 2) about the pivot points 3 by the handle 2, the cam faces will progressively come into contact with and then press firmly against the boat transom 8.

The final portion of this downward travel of the handle 2 causes the side plates 1 to come to rest in a slightly over-center position thus providing a degree of self locking ability. When the handle 2 is in the fully down position, that is approximately parallel to the boat transom, the cam faces 9 are thus forced to maintain a steady pressure against the boat transom 8, hence fixing the outboard motor firmly to the boat.

Preferably a spring loaded locking pin 11 is located on one of the two side plates, which, as the clamp is rotated to the over-centered position, will automatically engage in a correspondingly positioned hole provided in the side of the bracket 4.

As illustrated in Figure 4, a transom wear plate 13 may also be utilised. The plate 13 can be formed of any suitable material and may be fixed to the transom in a manner that the cam faces 9 will contact the wear plate as the clamp is being mounted onto the transom.

The wear plate has the particular advantage of preventing the transom from being excessively worn due to repeated contact from the clamping device.

In a modification of the side plate 1 illustrated in Figure 5, an auxiliary roller 14 is so positioned that as the side plates are being rotated into their clamping position, the rollers will contact either the transom 8 or the wear plate 13 and will therefore reduce wear on the transom or on the transom wear plate as the cam handle approaches its locked position. In a further modification, particularly when a transom wear plate is utilised, the plate 13 can be formed with a depression or the like into which a portion of the roller 14 will engage when the clamp has been mounted on the transom of the boat In a further modification as diagrammatically illustrated in Figure 6 a clamping plate 15 can be utilised and as shown the clamping plate may be connected by a number of hinged rods 16 to the side plates 1. As the cam operating handle is moved downwardly, the folded rods will be caused to straighten thereby moving the clamping plate into contact with the transom or transom wear plate. The final downward movement of the handle will cause the rods to come into alignment in a slightly over centre action, thereby providing the desired degree of locking ability.

To fit the clamp to an existing outboard motor and then to custom fit the motor to a boat, the existing screw bolt fitting of the motor is removed, and the bolts are withdrawn.

The adjustment bolts 6 are then screwed into the bolt holes 7 until their ends are clear on the inside and so that the bracket member can be fitted to the ends of the bolts using appropriate circlips. The outboard motor is then lowered onto the transom 8 and with the handle positioned in the locked mode by use of the locking pin 11, the two adjustment bolts are tensioned equally to achieve a firm fit between the clamp and the transom. The lock nuts 6a are then tightened to complete the custom fitting of the clamp onto the transom.

To use the clamp, the outboard motor is lowered onto the transom 8 with the handle 2 in the open position illustrated in Figure 3 and when in position, the handle 2 is moved progressively downwards through an arc. This action will bring the cam faces 9 progressively toward and finally into contact with the boat transom until the locking pin can be engaged.

The saw tooth surface 10 will assist in the effective gripping of the clamp onto the transom and will also assist in preventing the outboard motor from moving upward on the transom during use.

To release the outboard motor from the boat, the handle 2 is pushed slightly toward the boat transom, thus enabling easy release of the locking pin 11. As the then unlocked handle is moved forward and upward through an arc 12, the cam faces 9 are caused to be progressively disengaged from contact with the transom. A point is then reached when the handle 12 is at its highest travel, and with the cam faces by then well clear of the transom, the handle will provide a convenient lifting point enabling the outboard motor to be removed clear of the transom and be carried off by the user.

The clamp as illustrated in Figures 7 through 13 is also attachable to an existing motor mounting bracket 20. The clamp includes a yoke 22 of U shape formation having parallel spaced apart side arms 23, the free ends of which terminate in noses 24 which in use will contact the transom 25. An attachment plate 27 spans between the facing surfaces of the arms 23 and as illustrated the ends of the plate 27 are shaped to engage in slots 29 formed in the facing surfaces of the arms 23 so that the attachment plate can have forward and rearward sliding movement in relation to the arms 23 but is guided by the slots 29.

The attachment plate 27 has suitable mounting holes to allow bolts 30 to pass through the plate 27 to engage in screw threaded holes formed in the arms 21 of the motor mounting bracket 20 to secure the attachment plate 27 to the mounting bracket 20. The attachment plate also has a boss 32 with a bore 33. In a highly preferred form (see particularly Figures 11,12 and 13) the bore 33 includes two rack members 34 with the facing edges of the rack members being formed with screw threads.

A threaded shaft 37 passes through a suitable hole formed in the yoke 22 and through the bore 33 of the boss 32, with the free end of the shaft including a stop member 39 to prevent inadvertent withdrawal of the shaft 37 from the boss 32. As illustrated more particularly in these Figures, the shaft 27 includes flats 38 so that the first diameter of the shaft between the flats 38 is less then the second diameter of the shaft reckoned at 90° from the first diameter.

The end of the shaft 37 opposite the stop member 39 passes through a suitable hole formed in the yoke 22 and is provided with a pivot pin 40 which is engaged in holes formed in a bifurcated cam member 41. The cam member has a cam face 42 which will act against a cap 43 which in turn will act against an elastomeric washer which is located between the cap 43 and the yoke 22. The cam member 41 is provided with a T shaped handle 45.

To assemble the clamp, the attachment plate 27 is first secured to the outboard motor mounting bracket by the bolts 30. The metal cap 43 and the elastomeric washer are engaged on the shaft 37 and moved towards the cam member 41. The free end of the shaft 37 with the handle 45 held in the vertical position illustrated in Figure 7, is passed through the hole in the yoke 22 and into the bore 33 of the boss 32 with the flats 38 of the shaft 37 aligning with the teeth of the rack member 34. During this movement, the yoke 22 is held in a manner that the slots 29 will engage the ends of the attachment plate 27. This will enable the shaft to pass through the boss 32 with the free end of the shaft projecting through the bore 33 of the boss 32. The stop member 39 is then attached to the free end of the shaft 37 such as by a split pin or the like.

The parts of the clamp will then be in the position illustrated in Figure 12 where the flats 38 on the shaft 37 are out of engagement with the teeth of the rack member 34. The handle 45 is then pushed forwardly to move the yoke 22 towards the transom until the noses 24 of the arms of the yoke contact the transom whereupon the handle is rotated in the direction illustrated by the arrow in Figure 8 so the threaded surface of the shaft will engage with the threaded bore of the boss 32. This movement will tend to move the yoke further towards the transom of the boat. When in that position, the handle 45 is pivoted as illustrated by the arrow in Figure 9 so the cam faces 42 of the bifurcated arms will impact the face of the cap 43 which will be transmitted to and compress the elastomeric washer to further increase the clamping force of the arms of the yoke onto the transom.

It is also possible to yet further increase the clamping force on the transom by holding the handle in the vertical position and rotating it through 180 degrees which will

provide a tighter grip when the handle is then turned a quarter of a turn and the handle passed down to the clamping position illustrated in Figure 9.

The clamp also preferably includes a locking means which in the form illustrated in the drawings consists of a stub 47 (see particularly Figures 7,8 and 9) which projects outwardly from the yoke 22 and which is formed with a suitable hole 48 into which a pin (not shown in the drawings) or the like can be inserted when the handle has been pivoted to the operative position illustrated in Figure 9. This will prevent inadvertent movement of the handle from its operative position which could result in the clamp losing purchase on the transom. If desired, a more permanent locking means can also be employed such as the hasp of a padlock.

It will be understood that the various forms of the bracket as described and illustrated herein, herein can be fitted to existing outboard motors, and may also be embodied into the design and construction of newly manufactured outboard motor brackets.

Having disclosed forms of the invention, it will be apparent to those skilled in the art, that amendments and modifications can be made to the particular constructional features and yet still come within the general scope of the invention. All such amendments and modifications are intended to be included in the scope of this application.