Note: Descriptions are shown in the official language in which they were submitted.
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21553
FIELD OF THE INVENTTON
The present invention relates to boats, and~ more
particularly, to disassemblable boats that are formed in
sections.
BACKGROUND OF THE IN N~IO
The assembly of the hull of a small ~oat by combin-
i.ng transverse sections has a number of important advantages.
It is particularly advantageous when storing or transportinq
the boat~ For example, many smaller cruising boats are ill
suited to carrying a rigid~ non-inflatabl~ lifeboat or a
dinghy for use in reaching shore once the larger boat has
been moored. However, a rigid lifeboat or a dinghy that can
be disassembled may be more easily stored on deck or below
deck. Conventionally constructed boats used for fishing,
1~ sailing, and other recreational activities are often transport-
ed by automobiles or small trucks and must be carried by
trailer~ whereas a disassemblable boat might ~e carried on
the vehicle itself.
There are~ however, a number of significant dis-
advantages associated with ~oats formed of separable sections
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that may account for 'cheir lack of popularity. The assembly
of such boats so ~chat their sections are se~ured together in ~~
an acceptable manner can be a difficult and time-consuming
project. Many times, the construotion is such that the
sections cannot be assembled in the water, thereby defeating
many of the potential advantages of a disassemblable boat
since room must be available in which to assemble it and
sufficient personnel or equipment must be available to lift
it into the water after it has been assembledu Obviously, a
lD boat which requires time-consuming out of the water assembly
is entirely unsuitable for use as a lifeboat.
Another serious problem that may be encountered
with disassemblable boats is that of lealcage. Whenever
connections are required below the waterLine, it is common to
use through fasteners around which leakage can occur.
A principal objective of the present invention is
to provide a disassemblable boat of sectional construction
which avoids the problems and disadvantages mentioned above.
SUMMARY OF THE INVENTI_
The present invention resides in a boat that
includes a hull assembly formed by a combination of transverse
sections, including a bow section and a stern section. A
pair of tendons extend longitudinally along the hull assembly,
being held by attachment devices that keep them in tension~
thereby preventing separation of the sections~ The tendons
follow geodesic lines alon~ the hull, being positioned on
opposite sides of the longitudinal hull center line, below
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the waterline and below the neutral axis. The tendons are
best situated on the keel-most panels of the hull and below -- -
the chines. Preferablyl the tendons are positioned in
open grooves on the exterior surface of the boat hull but are
held in the grooves by tension alone.
An attachment means is provided for securing the
tendons to the hull and holding them in tension. Preferably,
it cQnsists of a towing eye at the bow and tensioning means
inside the stern sec~ion for tensioning the tendons against
the eye.
The tendons can be used in combination with
through fasteners that connect ad]acent sections above the
waterline with the tendons preventing separation beneath the
waterline. It is preferable that the various sections be
shaped and dimensioned so that they can be internested as a
further aid to storage with a minimum of space occupied.
Other features and advantages of the present
invention will become apparent from the following detailed
description, taken in coniunction with l:he accompanying
drawings, which illustrate, by way of example, the principles
of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a side elevation of an assembled boat
constructed in accordance with the invention;
FIG. 2 is a diagrammatic illustration of the hull
config~ration in which the lines A-~ correspond to similar
.,
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lines indicated in FIG~ l;
FIGo 3 is a plan view of the assembled boat; ~~
FIG. 4 is an enlarged fragmentary view of a portion
of the inside of the transom, taken as indicated by the arrow
4-4 of FIG. 3 and showing the attachment of the aft end of
the tendon;
FIG. 5 is an enlarged view of a fragmentary portion
of FIG. 1, as indicated by the arrow la, that shows an
interlock be~ween hull sections;
FIGo 6 is an elevational view of the stern of the
boat;
FIGo 6a is an enlarged fragmentary view of a portion
of the stern section r taken as indicated by the arrow 6a in
FIG. 6) the cables being omitted to show the grooves;
FIG. 7 is a end elevational view of the bow of the
boat;
FIG. 8 is a plan view of the boat :in a disassembled
condition with the sections internested
FIGo 9 is a side elevation, similar to FIG. 1,
showing a second boat constructed in accordance with the
invention;
FIG~ 10 is a plan view of the boat of FIG. l;
FIGo 11 is an elevational view of the stern of the
boat of FIG. 9; and
FIG. 12 is an elevational view of the bow of the boat
o FIG. 9.
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DESCRIPTION OF TRE PREFEKRED EMBODIMENTS
An exemplary boat 10, constructed in accordance
with the present invention and shown in FIGS. 1-8 of the
accompanying drawings; includes a hull assembly 12 formed by
four transverse sections 14, 16~ 17 and 18 arranged end-to-end.
The sections 14, 16, 17 and 18 each form a water-ti~ht
enclosure that is open only at the top~ W~en disassembled~
the sections 14, 1~, 17 and 18 can be internested as shown in
FIG. 8. The second mid-section 17 is the largest in each
dimension so that it can receive the first mid-section 16
which in turn receives and the stern section 18. The bow
section 14, which is the ~mallest, fits within the stern
section 18.
The sections 14, 16, 17 and 18 can be made, for
example, of fiberglass~resin, metal or ~wood. Alternatively,
they can be of laminated construction, preferably using a low
density core. The lines of this particular hull 12 assemly,
while exhibiting a compound curvature, can be developed from
plywood.
The mid sections 16 and 17 are each closed at
the fore and aft ends by transverse bulkheads 20, which are
parti~ions of about the same height as the vertical sides 22
of the boat 10 or slightly less. At the aft end of the bow
section 14 is a similar bulkhead 24 that mates with and is
contiguous with the fore bulkhead 20 of the first mid-section
16. In a similar manner, a fore bulkhead 26 on the stern
section 1~ mates with the aft bulkhead 20 of the second
mid-section 17.
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21553
As an aid in assembling the hull 12 and.aligning
the sections 14, 16, 17 and 18~ the bulkheads 20 of the -- -
mid-sections 17 and 18 carry lips 28 which extend over and
engage the top edges of the adioining bulkheads 24 and 26 (as
best shown in FIG. la) Thus, the sections 14, 16, 17 and 18
are interlocked and properly positioned.
There are apertures in the mating bulkheads 20, 24
and 26 that receive through fasteners 32. These fasteners 32
are positioned well above the waterline of the hull 12 so
that there is no significant leakage around them. Although
ordinary marine bolts can be used, the preferrred fasteners
32 are quarter turn cam lock fasteners of a type conventionally
used for marine applications.
It will be noted that once the hull 12 is assembled
and placed in the water, any weight in the center of the hull
will tend to force the sections 14, 16, 17 and 18 apart at
the bottom and together at the top. ~his is because the
I buoyancy at the longitudinal outer limits of ~he hull 12
¦ places the entire floating structure under a substantial
¦ 20 bending moment, thereby applying compressive forces at ~he
top and tensile forces at the bottom. There is an imaginary
neutral axis A' ~Fig. 1) extending longitudinally through
the hull 12 where the structure is neither in compression nor
in tension. To counteract the tendency of the sections 14,
16, 17 and 18 to separate at the bottom, it is necessary to
secure them below the waterline (not indicated) because there
are practical limits on the strength, rigidity, size and
weiyht of the sections that are obtainable in a structure
intended to float.
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Attachment of the sections 14l 16~ 17 and 18 below
the waterline is accomplished by two corrosion-resistant,
woven steel tendons 34 that extend along the hull 12 from
the bow to the stern. To receive these tendons 34, two
downwardly facing longitudinal grooves 36 are provided, each
extending along the bottom of the entire hu11 assembly 12
(see FIG. 4).
The lines followed by the tendons 34 and the
grooves 36 are geode5ic. That is, they are lines on the
external surface of the hull 12 naturally followed by the
tendons 34 when in tension/ i.e., they are the shortest lines
between the points at which the tendons are secured to the
hull. Thus, it is not necessary to manually position the
tendons 34 along the length of the grooves 36. The tendons
34 naturally fall into the grooves 36 when stretched over the
h~ll 12 and tend to resist forces that would displace them
laterally out of the grooves. However, the use of the
grooves 36 prevents the tendons 34 from chafing against the
hull 12. The grooves 36 also prevent the tendons 34 from
snagging on underwater obstacles and debris and protect the
tendons when the boat 10 is beached.
To hold the tendons 34 is tension, they are
commonly held at their fore ends by an eye 52 (FIG. 7), which
is referred to as a "towing eye" because it can also serve as
an attachment point for a painter. The towing eye 5~ should
be placed at an appropriate height to serve this dual purpose.
The aft ends of the tendons 34 extend up the outside of the
transom 38, over the top edge, and are releasably secured to
over-center levers 58 that are permanently mounted on the
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interior surface of the transom above the waterline and
inside the stern section 18. Once the over-center levers 58 ~~ -
have been latched~ they firmly secure the hullrsections 14,
16, 17 and 18 together along their adjoining lower edges~
S It should be noted that the hull 12 is symmetrical,
the tendons 34 being equally spaced from opposite sides of
the longitudinal hull center line B' passing on opposite
sides of the center board trunk 59 and any rudder assembly
(no~ shown). Th~ tendons 34 must be located below the
neutral axis A' and below the waterline of the hull 12.
One important advantage to the use of two tendons
34 is that they provide redundance, keepiny the hull 12
essentially intact and operational if one tendon should fail.
To minirnize the asymmetry in the event that one tendon 34
should fail, the geodesic lines chosen should be close to the
longitudinal center line B' (FIG, 3) or the keel if there is
oneO In addition, placement of the tendons 34 close to the
center line B' displaces them as far as possible from the
neutral axis A,' thereby giving the tendons the maximum
holding power for their tensile strength.
There are no apertures in the hull 12 below the
waterline to serve as sources of leakage. Moreover, each of
the hull sections 14~ 16, 17 and 18 can be made to Eloat by
i~self, permitting the boat 10 to be assembled in the water.
Very little time or skill is required to assemble the boat
10. Once disassembled, it requires a minim~m o~ space
since the hull sections 14, 16, 17 and 18 can be internested
and the tendons 34 can be coiled and placed inside the
sec~ions~
21553
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The principles of the invention are further illus-
trated by a second boat 60, shown in FIGS. g 12. The hull 61
includes three hull se~tions 62, 64 and 66 instead of four
as in the case of the boat lOo There are two tendons 70 that
5 extend symrnetrically along geodesic lines of the hull 61,
lying in grooves 72. At the bow, the tendons 70 are attached
to a towing eye 74 while in the stern section 68 they are
held in tension by over-center levers 76.
The principal difference between the boat 10
and the boat 60 lies in the shape of the hull fil. Although
the hull 61 is less efficient, having a less complex curvature
with hard chines, its construction is less difficult to
~abricate and les expensive. The placement of the tendons
70, however, is similar to that of the Eirst boat 10, being
i5 below the neutral axis and near to the center line. The
tendons 70 ~re, in accordance with the plarameters given above,
below t.he lowest chines of the hull 61 and on the keel most
panels of the hull.
While particular forms of the invention have been
illustrated and described, it will be apparent that various
modifica~ions can be made without departing from the spirit
and scope of the inventionO
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