U.S. patent application number 10/681668 was filed with the patent office on 2004-10-07 for finkeel for boats, with movable lee-boards.
Invention is credited to Bianchi, Gianfranco.
Application Number | 20040194683 10/681668 |
Document ID | / |
Family ID | 32842909 |
Filed Date | 2004-10-07 |
United States Patent
Application |
20040194683 |
Kind Code |
A1 |
Bianchi, Gianfranco |
October 7, 2004 |
Finkeel for boats, with movable lee-boards
Abstract
The invention relates to a finkeel (3) for boats, having a fixed
part (30) attached to the hull (2) of the boat and a movable part
consisting of two lee-boards (32, 33) hinged with respect to an
axis lying in the midplane (M) of the finkeel. The two lee-boards
(32, 33) rotate independently of each other, so that one may be
used to counter heel the inclination of the boat caused by the wind
during sailing, while the other allows to keep unchanged the
resistance to the leeway of the hull.
Inventors: |
Bianchi, Gianfranco;
(Genova, IT) |
Correspondence
Address: |
INTELLECTUAL PROPERTY GROUP
FREDRIKSON & BYRON, P.A.
200 SOUTH SIXTH STREET
SUITE 4000
MINNEAPOLIS
MN
55402
US
|
Family ID: |
32842909 |
Appl. No.: |
10/681668 |
Filed: |
October 8, 2003 |
Current U.S.
Class: |
114/140 |
Current CPC
Class: |
B63B 41/00 20130101 |
Class at
Publication: |
114/140 |
International
Class: |
B63B 003/38 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 4, 2003 |
EP |
03425207.2 |
Claims
1. Finkeel for boats, characterized in that it comprises a fixed
portion with an end for connection to a hull and a moving portion
comprising a pair of lee-boards arranged on the fixed portion,
rotatable in a hinged manner on opposite sides with reference to a
midplane of the fixed part.
2. Finkeel according to claim 1, wherein the lee-boards are
rotatable independently of each other.
3. Finkeel according to claim 2, wherein the lee-boards are
provided with respective ballast elements.
4. Finkeel according to claim 3, wherein the ballast elements are
arranged at the ends of the respective lee-boards.
5. Finkeel according to claim 1, wherein the lee-boards are
rotatable with respect to a same axis lying on a midplane of the
fixed portion.
6. Finkeel according to claim 5, wherein the lee-boards are hinged
on a shaft arranged along their axis of rotation by means of
respective sleeves.
7. Finkeel according to claim 6, wherein at least one of said
sleeves is rotationally integral with the shaft where the arms are
arranged, said arms being operated by respective actuators.
8. Finkeel according to claim 7, wherein at least one of said
sleeves is idle with respect to the shaft and is provided with arms
operated by respective actuators.
9. Finkeel according to claim 1, wherein the lee-boards are
substantially symmetrical and adjacent to each other in the
condition aligned with the midplane of the hull.
10. Finkeel according to claim 1, wherein the lee-boards have a
matching form with elements interposing with each other, in the
condition aligned with the midplane of the fixed part.
11. Finkeel according to claim 1, wherein the lee-boards are
rotatable about respective parallel axes arranged on opposite sides
with respect to the midplane of the fixed part.
12. Finkeel according to claim 1, wherein the lee-boards extend
from the end of the fixed part, opposite to the connection end
thereof.
13. Finkeel according to claim 2, wherein the axes of rotation of
the lee-boards are arranged parallel to the longitudinal axis of
the boat's hull.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to European Application No.
03425207.2, filed Apr. 4, 2003, which is incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] The invention relates to boats, in particular sailing boats,
equipped with a finkeel.
[0003] As is known, sailing boats normally have a keel with a fin
protruding downward from the hull, called finkeel, at the ends of
which there may be a bulb containing lead or other heavy material
suitable to form a ballast.
[0004] In small boats the fin may be raised or lowered manually in
its plane, to extract it from the hull or immerse it in the water
at different depths, while in larger boats it is fitted to the keel
in a fixed manner, i.e. such that it cannot be extracted from the
hull.
[0005] The present invention relates in particular to this second
type of finkeel which may be, in turn, rigid, i.e. integral with
the hull, or movable with respect thereto for adjusting the trim of
the boat.
[0006] Finkeels allow to obtain advantageous effects including that
of counter-heeling the inclination of the boat caused by the
wind.
[0007] In order to improve this effect, finkeels have been
developed that can swing to the right or to the left with respect
to a longitudinal midplane of the boat.
[0008] To this purpose the finkeel is hinged at the bottom of the
hull and is canted with respect to its hinging axis, by means of
actuators, according to needs.
[0009] This type of finkeel is effective as regards the righting
moment of the boat when the latter is subject to heel, because
rotation of the finkeel allows the distribution of the weights to
be changed, thereby better offsetting the force of the wind.
[0010] Indeed, the righting moment is equivalent to the product of
the weight of the finkeel, by the distance of its centre of gravity
from the longitudinal axis of rotation of the boat.
[0011] However, by rotating the finkeel as mentioned above, the
hull transverse resistance to the leeway is reduced considerably as
a result of the reduction in the effective resisting surface of the
finkeel itself.
[0012] Indeed, for righting the boat it is necessary to displace
the finkeel towards the side where the wind is blowing: this
however results in a reduction in its effective surface opposing to
the leeway.
[0013] For compensating this effect, it is known to provide on
boats additional movable foils which are lowered into the sea when
sailing with the finkeel in the displaced position.
[0014] It is clear that this provision involves additional
difficulties since it requires the use of specific means and
manoeuvres, which in any case it would be better to avoid from
doing or using.
[0015] The technical problem underlying the present invention is
therefore that of overcoming the limitations of the state of the
art considered above and, more generally, improving the performance
of the finkeels in known boats.
SUMMARY OF THE INVENTION
[0016] The idea for solving this problem is that of providing a
finkeel having a fixed base portion fixed with respect to the hull,
and a moving end portion formed by two lee-boards hinged in book
arrangement at the end of the fixed portion, rotatable
independently of each other.
[0017] In this way it is possible to modify the righting moment of
the boat with an optimum ratio between the righting moment and the
weight of the finkeel, without adversely affecting its resistance
to the leeway and with the considerable advantage of having the
weight of the finkeel situated at a lower level, although not
affecting the draught of the boat.
[0018] The characterising features of the invention are
specifically set forth in the appended claims; they will result
better in view of the description provided below, of a pair of
embodiments of the invention illustrated in the accompanying
drawings.
DESCRIPTION OF THE DRAWING
[0019] FIG. 1 shows the hull of a boat with a finkeel according to
the invention;
[0020] FIG. 2 shows a cross-section through the hull of FIG. 1;
[0021] FIGS. 3 and 4 show the finkeel of the above hull, in
respective operating conditions;
[0022] FIG. 5 is a partially sectioned side view of the finkeel of
FIGS. 3 and 4;
[0023] FIG. 6 is a cross-section along the line VI-VI in FIG.
5;
[0024] FIGS. 7 and 8 show respective details of FIG. 5;
[0025] FIGS. 9 and 10 show another embodiment of the finkeel above;
and
[0026] FIG. 11 shows another embodiment of a finkeel.
DETAILED DESCRIPTION
[0027] With reference to the drawings, numeral 1 denotes a boat
whose hull 2 is equipped with a finkeel 3 according to the
invention.
[0028] The finkeel 3 comprises a fixed portion 30 extending
downwards from the hull 2 in a manner similar to that of
conventional finkeels, and a moving portion consisting of two fins
32 and 33 projecting from the fixed part and rotating with respect
to a common horizontal hinging axis X, lying in the midplane M of
the finkeel.
[0029] The fixed portion 30 is applied to the hull 2 at a
connection end 30a, using fixing means not shown in the drawings
and known per se; the junction may be of the removable type,
preferably obtained by means of mechanical systems (bolts, cramps,
etc.), or of the permanent and stable type obtained by applying
resins or other materials, suitable for rigidly joining the
connection end of the finkeel to the hull.
[0030] The moving lee-boards 32, 33 may be closed or opened like a
book (FIGS. 3 and 4) independently of each other, by causing them
to rotate about the hinging axis X; for this purpose a bulb-shaped
part 34 is present at the end of the fixed portion 30, housing
means for rotation of the lee-boards.
[0031] The latter are moreover configured symmetrically with
respect to the midplane M of the finkeel and in this example are
each equipped with a respective ballast element 36 and 37.
[0032] The rotation of the lee-boards mentioned above takes place
independently of each other by means of a system which may be of
the electromechanical, hydraulic or other type.
[0033] In the example shown, operation of lee-board 33 is made by
means of a shaft 40 which is rotatably supported inside the
bulb-shaped part 34, by two bearings 41 and 42; at the opposite
ends of the shaft 40, respective pairs of radial arms 43 and 44 are
present, while a sleeve 45 formed as one piece with the lee-board
33 is keyed in its central zone. Keying may be achieved by means of
longitudinal grooves or in any other suitable way known per se.
[0034] The lee-board 33 is then displaced integrally with the
central sleeve 45 by the rotations of the shaft 40, which are
imparted by hydraulic actuators 47 and 48 acting on the arms 43 and
44 located at its ends; the hydraulic actuators are fed with
operating fluid by a pump situated on-board the boat and connected
thereto by means of ducts passing inside the fixed portion 30 of
the finkeel. Neither the pump nor the ducts are shown in the
drawings since they are known per se.
[0035] Furthermore on the shaft 40 there are mounted idle, by means
of bearings 50, two cylindrical sleeves 51 and 52 formed as one
piece with the other lee-board and having two extensions 51a, 52a,
with which pairs of radial arms 53 and 54 are respectively
associated.
[0036] Likewise before, said arms are operated by respective
hydraulic actuators 55 and 56 which cause rotation of the sleeves
51, 52 and of the lee-board 32, together therewith; also in this
case the actuators are connected to a supply pump arranged on-board
the boat, by means of through-ducts passing in the fixed portion of
the finkeel.
[0037] From what has been explained hitherto it is easy to
understand the mode of operation of the finkeel according to the
invention.
[0038] Indeed, during ordinary sailing conditions of the boat 1,
the two lee-boards 32, 33 of the finkeel 30 are closed, thereby
providing the latter with the configuration of a traditional
finkeel.
[0039] On the other hand, when the hull 2 is inclined and it is
needed to counter heel this inclination, it is sufficient to cant
the lee-board 33 of the finkeel 30 which is situated on the
windward side namely, in the case of FIG. 2, the left-hand
side.
[0040] In this manner the lee-board 33 together with the ballast 37
is displaced, moving away its centre of gravity from the midplane M
such that its weight increases the moment that counter-heels the
inclination of the boat caused by the wind.
[0041] Canting of the lee-board 33 is obtained by rotating the
shaft 40 on which its sleeve 45 is keyed; as explained above,
rotation of the shaft is in turn performed by the actuators 47,
48.
[0042] In FIG. 2, the other lee-board 32 remains immobile in the
initial position aligned with the midplane M, so that the
transverse resistance to the leeway of the hull 2 remains unchanged
with respect to its normal sailing condition.
[0043] It is obvious that, when the inclination of the boat occurs
in the opposite direction to that of FIG. 2, the lee-board 32 will
be displaced in order to right it; this operation takes place as a
result of rotation of the sleeves 51, 52 integrally with the
lee-board 32.
[0044] For this purpose the actuators 55, 56 operate the radial
arms 53, 54 of the extensions 51a, 52a of the sleeves, in a manner
similar to that already seen above; in this case the lee-board 33
will remain aligned with the midplane M.
[0045] As can be seen, therefore, the finkeel 3 considered above
solves the technical problem underlying the present invention.
[0046] Indeed, while in the known art the displacement of the
movable finkeel for righting the boat increases the tendency of the
hull to drift, now with the two independent movable lee-boards 32,
33 it is possible to obtain simultaneously the dual effect of
counter heeling the inclination of the hull and keeping unvaried
its resistance to the leeway.
[0047] With reference to FIG. 2 it is further pointed that if the
lee-board 32 is rotated so as to lay it vertically, the resistance
to the leeway is also increased; however, it must be pointed out
that in the finkeel according to the invention the lee-boards 32,
33 may also be rotated in the same direction, to increase the
righting moment of the hull.
[0048] There are, however, other important advantageous effects
achieved by the finkeel according to the invention.
[0049] Firstly it must emphasized that the two lee-boards 32, 33
are symmetrical with respect to the axis of rotation X and have a
limited length, because the finkeel 3 also comprises a fixed
portion 30: consequently, in normal sailing conditions, i.e. with
the boat not inclined as explained above, the two lee-boards 32 and
33 may be used as fixed lee-boards of the type used nowadays on
some boats. FIG. 4 shows a possible use of the lee-boards in this
condition.
[0050] The division of the finkeel into a fixed portion and a
moving portion with the lee-boards is moreover advantageous for the
draught of the boat.
[0051] Indeed, as is known in some ports there is a limited depth
which does not allow the entry of boats with a draught greater than
a certain predefined value; it can be easily understood that with
the finkeel according to the invention, it is possible to fold the
lee-boards upwards thereby reducing the draught to the sole fixed
portion.
[0052] The symmetry of the lee-boards allows to effectively reduce
the draught without heeling the boat, contrarily to what would
happen in the case of boats of the known type, where if the sole
rotating finkeel is canted to reduce the draught, the centre of
gravity is also displaced thereby resulting in an imbalance of the
boat's trim.
[0053] It is also evident that short lee-boards such as those
according to the invention require motors, pumps, racks or other
means generally intended for rotation thereof, smaller and lighter
than those used in the known art, with the obvious advantages
arising therefrom.
[0054] Of course, variations of the invention with respect to the
foregoing are possible.
[0055] For example, it is clear that the solutions for mounting and
rotating of the lee-boards may vary greatly; it is therefore
possible to use alternative systems in which, instead of the
hydraulic actuators, there are mechanisms with connecting rods and
cranks or gears which transmit the movement to the shaft 40, or
other solutions in which there are electric motors arranged inside
the bulb-shaped part 34, which directly actuate the shaft 40 and
the sleeves 51, 52.
[0056] Also as regards the form of the lee-boards it is possible to
provide alternative designs;
[0057] for example FIGS. 9 and 10 show a finkeel wherein the
lee-board 32 is divided into two elements 32', 32", while the
lee-board 33 has a width such that it can be arranged between these
elements.
[0058] As can be seen, in the vertically aligned condition this
solution is equivalent to the one above since the lee-boards are
joined together; however, in the case of the same total weight of
the finkeel, the centre of gravity is located in a lower point.
[0059] Finally, as a further possible variant it may be to
envisaged to provide a finkeel according to the invention, in which
the lee-boards 32, 33 are respectively hinged about two parallel
axes (X' and X") arranged on the fixed portion 30, as shown in FIG.
11, instead of about a single axis X as in the previous cases.
[0060] This solution has the advantage of giving the possibility to
use lee-boards of the "open" type like those in FIGS. 9 and 10,
which however are symmetrical since they do not have to penetrate
inside each other as shown in FIG. 9 because they may be arranged
adjacent to each other, being hinged on two different axes. It just
matters to be added that the hinging and actuation of these
lee-boards is entirely similar to that explained above.
[0061] Last, also in relation to the actuation of the lee-boards it
must be pointed out how the shaft and the sleeve elements are
simple and reliable, also because they are suitable for the use of
sealing means between the parts in relative movement; this is
applicable to the sleeve elements 51, 45 and 52 between which
sealing rings made of material resistant to sea water, such as
teflon or the like, may be arranged.
[0062] It is nevertheless possible to design different systems
depending also on the form of the lee-boards above.
[0063] All of these variants nevertheless fall within the scope of
the following claims.
* * * * *