[0001] This invention relates to outboard brackets for inflatable boats. These are per se
known objects which are used to enable the attachment of an outboard motor to an inflatable
boat which does not have a rigid transom.
[0002] Current outboard brackets are fabricated parts which are fitted, by means of projecting
rods and hooks, into projecting eyelets on a pre-inflated tube of the boat.
[0003] Both the fabrication of these brackets and their fitting to the tube present considerable
disadvantages, for example in terms of cost, visual appeal and corrosion resistance.
[0004] According to one aspect of the present invention an outboard bracket for an inflatable
boat is a one-piece integral member having a portion adapted to overlie the surface
of an inflated tube of an inflatable boat, a portion projecting therefrom and adapted
to mount an outboard motor thereupon, and securing means in the conforming portion
adapted to interact with securing means on the tube, upon inter-engagement of those
means while the tube is in less than fully inflated condition, whereby locking inter-engagement
of those means is achieved by a fuller inflation of the tube.
[0005] In a preferred embodiment the securing means on the conforming portion are keyhole
slots arranged at opposite ends of the conforming portion and spaced apart around
the arcuate circumference of the conforming portion, adapted to be engaged by studs
projecting from the tube and entering through the wider portion of the keyhole slot
for forming an engagement, and being urged into a narrower portion of the keyhole
slot upon fuller inflation of the tube. In a preferred embodiment there are a pair
of such apertures at each of the respective ends, the keyholes of one pair being arranged
in orthogonal directions in relation to the keyholes of the other pair. Alternatively,
the keyholes of both pairs may be arranged in parallel but opposed.
[0006] Preferably, the conforming portion is held a small distance away from the tube by
the securing means, to prevent chafing of the tube by the edges of the bracket. Distances
of less than 5 mm are preferred, 3 mm being suitable.
[0007] In further possibilities, at least one end of the conforming portion may be adapted
to inter-engage with a receiving pocket on the tube whereby inflation of the tube
assures penetration of the respective end of the receiving portion into the pocket
and retention by that pocket.
[0008] The invention provides in another aspect a method of fitting an outboard bracket
to an inflatable boat which consists of inter-engaging the bracket with a tube of
the inflatable boat in a condition when the tube is less than fully inflated, and
increasing the inflation of the tube to cause a locking inter-engagement of the tube
and the bracket. Preferably this locking inter-engagement is provided by the inflation
of the tube forcing apart projections provided on the tube into keyhole slots provided
on the bracket.
[0009] Particular embodiments of the invention are described with reference to the accompanying
drawings, wherein:
Figure 1 is a perspective view of an outboard bracket embodying the invention mounted
on an inflated tube of an inflatable boat, and at the stern thereof;
Figure 2 is a view of the tube in deflated condition;
Figure 3 shows a step in the fitting of the bracket to the tube; and
Figure 4 shows an embodiment of a bracket fitted to the tube.
[0010] In the drawings, we see the rear tube portion 1 of the flotation tube 2 of an inflatable
boat 3. An outboard bracket 4 is fitted to the tube 1. This outboard bracket is a
one-piece moulding (made by any suitable technique such as vacuum-forming, hand layup
from glass reinforced plastics, or cold or hot pressing of glass reinforced plastics)
and has a saddle-like part 5 conforming to the inflated curvature of the tube 1. It
also has an upstanding flange part 6 with generally parallel front and rear walls
which is for the reception of a fixing clamp of an outboard motor which is destined
to propel the inflatable boat. A location recess 7 in a top edge of the flange part
helps retain the motor fixing from lateral displacement. A handle 8 is moulded into
the lower end of the bracket to assist carrying of the boat with the engine removed.
Side walls 9,10 join the flange to the conforming part and strengthen the assembly.
[0011] At each of its ends 11 and 12 which are separated by the curvature of the conforming
surface of the part 5, the bracket has securing means 13 which in the embodiment are
keyhole slots penetrating the thickness of the conforming portion. These keyhole slots
each have a wide and a narrow portion as can best be seen in the lower part of Figure
3. In the embodiment of Figured 1 to 3 onwards, the keyhole slots are in pairs, one
pair at each end of the conforming part 5, with the axes of elongation of each pair
of slots being collinear and the two axes lying parallel; however, the direction of
the slots as best seen again from Figure 3 is opposed in the sense that the narrower
ends are mutually apart from each other. It will be understood that the illustrated
arrangement of slots is that presently preferred; other orientations can give satisfactory
results. For example, in Figure 4, the respective axes of elongation of slots 13 on
the one hand and of slots 16 on the other, are perpendicular.
[0012] The tube 1 is adapted to receive brackets by the provision of securing means upon
it, which in this embodiment are four studs 14 the base of each of which is securely
bonded to the tube. The base is then followed by a narrow neck and an enlarged head
15 which is smaller in diameter than the large portion of the slot 13,16 with which
it is to engage but larger than the width of the narrower portion of the slot. The
spacing apart of the studs on the tube is such that when the tube is fully inflated
the narrow stems of each of the studs will be occupying the narrow part of each of
the slots 13,16.
[0013] To fit the bracket, the tube is deflated so that the surface upon which the studs
are borne becomes floppy and their heads may be introduced through the (incorrectly
spaced) wider portions of the keyhole slots 13. The tube is then inflated, this imposing
rigidity on its fabric and forcing apart the studs to their natural spacing in which
their narrow necks are urged into and retained in the narrower part of the keyhole
slots. The bracket is thereby inter-engaged and interlocked with the tube until such
time as the latter is again deflated.
[0014] As has been mentioned, in the embodiment seen in Figure 4, the bracket 4' has slots
13 as before at one end of the conforming portion 5 but at the other end a pair of
slots 16 are arranged with their axes parallel to each other and both these axes being
orthogonal to the common collinear axis of the slots 13. In this embodiment the effective
inflation of the tube is to force the four studs apart but in essentially orthogonal
directions as between one pair and the other. In the slightly modified embodiment
of Fig 1, the four slots are parallel but opposed. The effect is the same.
[0015] It is clear that there are other means by which the same effect may be obtained.
For example the engaging means on the tube need not be stud-like as shown here but
could be an outwardly directed hook; and the securing means on the bracket need not
necessarily be slots. It is also possible to provide protrusions on the surface of
the moulding of the bracket, or width restrictions along the length of the keyhole
slot which interfere with the motion of the stud, thereby to provide at least some
resistance to disengaging of the bracket. For example, at least one end of the conforming
part of the bracket could be engageable in a pocket arranged on the outside of the
tube, inflation of the tube then rigidifying the tube and maintaining the relative
spacing of the pocket or pockets so that there is a positive interlocking engagement.
Furthermore, although less advantageously, one end of the bracket could be secured
by some conventional means such as a strap or lacing.
1. A bracket (4) for mounting an outboard motor to a tube (1) of an inflatable boat (3),
the bracket comprising
a portion (6) for receiving said motor;
a conforming portion (5) adapted to overlie said tube;
securing means (13,16) on the conforming portion positioned to be interengageable
with securing means (14,15) on the tube, the securing means (13-16) being positioned
so as to be locked in interengagement upon inflation of the tube (1).
2. A bracket according to claim 1 wherein said securing means on said conforming portion
is a slot (13,16) and on said tube is a projection therefrom (14) and said interengagement
is by an overlap portion (15) on said projection, inflation causing overlap of said
overlap portion over an edge of the slot to cause locking interengagement.
3. A bracket according to claim 2 wherein said conforming portion has parallel upper
and lower edges (11,12) and there is a pair of said slots adjacent each of said edges.
4. A bracket according to claim 2 or claim 3 wherein said slots (13,16) each having two
portions, one being wider than the other and wherein said overlap portion (15) is
a head of a stud (14) forming said projection, said head being wider than the less
wide portion but narrower than the wider portion of the slot.
5. A bracket according to claim 4 wherein the elongations of said slots adjacent the
respective edges are all parallel.
6. A bracket according to claim 4 wherein the elongations of said slots adjacent and
said edge are perpendicular to the elongations of said slots adjacent the other said
edge.
7. A bracket according to any one of the preceding claims mounted on and in combination
with an inflatable boat (3), said securing means (13-16) on the bracket (4) and on
a tube (1) of the inflatable boat being held in locking interengagement by virtue
of the inflation of said tube.
8. A bracket as claimed in claim 7 with an outboard motor mounted to said receiving portion.
9. A method of securing to an inflatable boat (3) a bracket (4) for mounting an outboard
motor to said boat comprising providing securing means (13-16) on an inflatable tube
(1) of said boat and on a portion (5) of said bracket, in an at least partially deflated
condition of said tube placing said securing means together, and inflating said tube
to cause a locking interengagement of said securing means thereby and retain said
bracket on said tube.