MAT POUR VEHICULES A VOILE

MAST FOR SAILING VEHICLES

Abrégé français

L'invention concerne un mât pour véhicules à voile divisé dans le sens latéral en deux profils de mât (moitiés de mât) (1) symétriques, réunis sur ou sous le haut du mât, espacés sur la base du mât, courbés vers l'extérieur en forme d'arc ou s'étendant en ligne droite, le transfert des forces actives s'effectuant par l'intermédiaire d'un étai intérieur (2) et de branches intérieures (3) dont la disposition et le nombre permettent d'obtenir la stabilité de forme et l'avantage statique de cette construction. La division du mât en deux profils permet d'obtenir une amenée directe de la grand-voile (10), la réalisation des moitiés de mât et de leur forme de profil (8), (9) s'effectuant de préférence de manière aérodynamique.

Abrégé anglais

The invention relates to a mast for sailing vehicles, said mast being divided in a lateral direction into two mirror symmetrical mast profiles (mast halves) (1) which merge at or under the top of the mast, which are placed apart on the base of the mast, and which curve outward forming arcs or run in a straight manner. Acting forces are transferred via an inner stay (2) and inner spokes (3), by means of the arrangement and number of which the dimensional stability of the construction and of the static advantage thereof is achieved. A direct flow onto the mainsail (10) is enabled by the division of the mast into two profiles, the design of the mast halves and the profile shape thereof (8), (9) being preferably carried out in an aerodynamic manner.

Revendications

CLAIMS:
1. A mast for a sailing vehicle, characterized in that a division of the mast
in a lateral
direction results in two mirror-image mast halves, which merge at a mast top
and are apart
from one another at a mast base, forming curved or straight mast halves, and
the transfer
of acting forces takes place through an inner stay and inner spokes.
2. The mast according to claim 1, characterized in that a design and an
arrangement
of the mast halves and its profile form is carried out in a streamlined form.
3. The mast according to claim 1, characterized in that the mast halves are in
each
case provided with a straight or a partially straight design, and that they
merge inclined to
each other at the mast top or below the mast top.
4. The mast according to claim 1, characterized in that instead of the stay,
the luff of
the main sail transfers vertical tension with a simpler construction.
5. The mast according to claim 1, characterized in that the central stay is
provided
with a guide rail for accommodation of the mast slider (of the luff).
6. The mast according to claim 1, characterized in that the profile of the
mast halves
is maintained open for a light design and provided with a light material or
sail canvas
inside a covering. (Fig. 2)
7. The mast according to claim 1, characterized in that each (open) profile of
the mast
halves faces with its concave side outward, and that the mast halves are
supported and
connected to each other by pressure elements.
8. The mast according to claim 1, characterized in that a strip of canvas is
mounted in
order to improve wind guidance and to enlarge a sail area, respectively, on
rear edges
throughout an entire length of the mast halves.
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9. The mast according to claim 1, characterized in that adjustable guide
profiles are
mounted in order to improve wind guidance throughout an entire length of the
mast
halves.
10. The mast according to claim 1, characterized in that a profile of the mast
halves is
designed in a streamlined and high-strength form as a strutted hollow profile.
11. The mast according to claim 1, characterized in that the mast is mounted
in a fixed
manner on a boat body and that resulting forces are introduced directly
through a mast
base into a hull.
12. The mast according to claim 1, characterized in that the mast is mounted
rotatably.
13. The mast according to claim 1, characterized in that the mast is mounted
pivotably.
14. The mast according to claim 1, characterized in that the mast is mounted
rotatably
and pivotably.
15. The mast according to claim 1, characterized in that when a rotatable (and
pivotable) execution is used, the beam is firmly connected to a mast
construction and it
swivels during a rotation.
16. The mast according to claim 1, characterized in that a design of the mast
halves is
realized by an aluminum extruded profile or by carbon materials and laminates.
17. The mast according to claim 1, characterized in that a design is realized
by
(plastic/carbon) laminates in a composite construction.
18. The mast according to claim 1, characterized in that a design of spokes is
realized
in a simple construction as a round profile, with wire or rope articles having
an optimal
construction as a streamlined flat material manufactured from steel carbon
materials/laminates or from plastic materials.

19. The mast according to claim 1, characterized in that pressure elements are
additionally attached to spokes between the mast halves for high and varying
loads.
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Description

CA 02789767 2012-08-14
MAST FOR SAILING VEHICLES
The present invention relates to a mast for dinghies, sailing ships and
sailing
vehicles of any type, which consist of two mast halves placed laterally apart
and
transversely to the longitudinal axis which are outwardly curved, arched or
run straight,
and merge at or under the top of the mast and reach the largest structural
width so that the
stay deployed centrally between the mast halves or the luff of the sail
creates a vertical
tension and the spokes deployed transversely between the mast halves support
the
transverse forces, wherein dimensional stability of this construction and
statistical
advantage is achieved with their arrangement and number. The design of the
mast profile
is provided preferably with an aerodynamic form in a known manner.
With the usual mast design form, the bending moment generated by the lateral
wind pressure on the mast is absorbed by a shroud bracing outwardly spread by
(several)
spreaders and the resulting forces are introduced through the shroud into the
hull of the
boat on the windward side.
Both the spreaders and the mast absorb the load created by the wind forces and
the
prestressing forces on the rigging and the stays. For aerodynamic and weight
reasons, the
mast and the spreaders should be maintained as slender or thin as possible.
However, in
order to avoid buckling, the technical thinness of the design is limited, so
that the mast is
in the usual construction form provided with a wide profile and a high weight
for
resistance to buckling, and by being placed in front of the sail, it is held
with the luff in a
mast rail, which has a negative influence on the incoming flow of the wind
relative to the
course of the boat on the wind. When airflow enters the sail, the flow is cut
off and
vortices are generated on the air side and on the downwind side in the area
behind the
mast.
The flow-related technical problem is known and attempts were made to solve it
in
various manners. This problem is solved in WO/03889 by an arrangement of
additional
profiles or a pair of special vanes arranged next to the mast, wherein this
solution of the
problem deals with the disadvantage of additional load, which increases the
heeling
moment.
In patents FR 1 524 392 A, US 3 724 412 A, GB 1 399 421 A and FR 2 751 609
Al, the static advantage is disregarded and a higher weight or a smaller
bending resistance
of the construction are considered acceptable.
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CA 02789767 2012-08-14
The object of the invention is therefore to improve the statics through the
design of
a mast in the manner described above, while positive flow characteristics are
also taken
into account.
With the mast design according to the present invention, the forces resulting
from
the wind pressure and from prestressing are transmitted through the arc shape
or through
the straight design of the mast halves in the form of pressure forces, and in
the form of
traction forces through spokes and through a centrally deployed stay.
Due to the ratios between the forces on which the construction of the
invention is
based, a ratio to the number of the employed spokes and to the frequency of
subdividing is
created for both mast halves which significantly reduces the propensity of the
mast halves
to buckling, which in turn results in a significantly thinner design of the
two profile halves
of the mast.
The resistance torque of the mast perpendicular to the wind direction must be
considered to be significantly higher due to the width of the construction
with the
construction design according to the invention.
Moreover, the static advantage of the construction according to the invention
is the
result of the significantly more resilient spokes relative to their thin
design which is
exposed to the tensile forces, as well as based on the abundance of the
arrangement of the
spokes, or on a better distribution of the forces throughout the entire length
of the mast
halves. The construction in accordance with the invention thus results in a
higher stability
of the mast relative to its weight.
In one variant of the construction according to the invention, the mast halves
run
straight or partially straight, and the tendency to buckling in a certain
direction is due in
this case to the asymmetric (inner) material stresses related to the profile,
in each case in
the direction of the convex side of the (open, semi-circular) profile of the
mast halves,
wherein buckling can be avoided with an appropriate arrangement of the spokes
or of the
pressure elements, in relation to their frequency.
Direct air flow to the sail is thus made possible because of the arrangement
of the
sail centrally between the mast halves.
In contrast to Utility Model G 92 07 461.8, the bifurcation of the mast is not
used
based on the present concept to increase the sail area by implementing the
beam through
the sail, but instead it is used to increase the stability of the mast itself.
The present
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CA 02789767 2012-08-14
construction thus enables static redirection very effectively, even with
extremely high
wind pressures.
The resulting aerodynamic advantage is obtained from the direct airflow to the
sail,
as described in a similar form in patents FR 1 524 392 A, US 3 724 412 A, GB 1
399 421
A and FR 2 751 609 A. In addition, the more slender design of both profile
halves of the
mast also makes it possible to attain a corresponding execution of the vane
profiles which
is more streamlined, so that a better airflow can be achieved to the main sail
with the
course on the wind. The airflow can be further improved when the construction
is realized
as a rotatable construction.
The spokes deployed on the inner side do not result thanks to the small, round
or
flat elliptical profile in any significant vortexes or air resistance values.
The sail can be raised on the central stay, or with lighter forms (small
dinghies)
hooked into the spokes along the length of the luff of the sail, but it can be
also freely
extended between the mast and the mast base (construction without a central
stay).
The introduction of the lateral wind forces in the hull of the boat takes
place either
directly via the mast base mounted on the deck, or additionally also through
the shrouds,
which can act in its turn deep at the height of center of gravity at the inner
stay the sail,
resulting in a further weight loss of the entire rigging and in a not
insignificant lowering of
the center of gravity of the mast and of the rigging.
Furthermore, control over Genoa sail is facilitated with the more slender
construction form of the spread mast and the deeper deployment of the
spreaders.
As shown in the diagram of Fig. 1, a boat is indicated in front view, which
comprises the construction form of the mast according to the invention
provided with two
mast halves 1 and with the inner stay 2, which is connected through frictional
force with
the arc ends (4) and with the mast base 5, and which tensions the curved mast
halves
vertically in the longitudinal axis. The spokes 3 provide for the bracing of
the mast halves
to each other, transversely and obliquely to the longitudinal axis. Optional
shrouds 6
additionally conduct the generated forces into the boat body 7. Fig. 2 and
Fig. 3 represent
the profile forms 8 and 9 of the mast halves in a cross-section normal to the
longitudinal
axis of the mast.
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Dessin représentatif