[0001] The present invention relates to an improved water-jet, in particular for the control
and the drive of boats. More specifically, the invention relates to a water-jet created
and structured in such a way as to be substantially self-cleaning, by automatically
removing all debris traditionally formed on boats, in particular in the marine environment,
that is "fouling".
[0002] The use of water-jets to command and drive boats has been object of a remarkable
development in recent years.
[0003] Further to the use as elements of conventional drives, the water-jets are used for
example as bow and stern propellers, in particular to equip boats of a control system
that allows to maneuver easily, for example in port during docking and/or output,
even boats of considerable size.
[0004] In some cases, these systems are also used to counter the drift phenomenon, which
occurs typically in sailing boats; it is a maneuver that is not particularly pleasing
to sail "purists", but it is certainly useful in certain condition.
[0005] Mostly, the use of this system of control is limited to the operations in port, as
it requires a high consumption of batteries.
[0006] In the attached Figure 1 is shown an example of a boat 10 bow and stern system, which
employs water-jets.
[0007] The system of Figure 1 is of conventional type, even if the same can be applied to
the water-jets according to the invention.
[0008] In particular, the system of Figure 1 includes two groups of stern jets 1, 2 and
two groups of bow jets 3, 4.
[0009] Each group of jets 1, 2, 3, 4, provides a socket jet 1', 2', 3', 4' and a thrust
jet 1", 2", 3", 4", respectively, connected by conduits 5, with the interposition
of a valve assembly 6 of adjustment and flow rate.
[0010] Both the complex of bow and of stern provide a motor 7 and a diaphragm pump 8.
[0011] In the attached figures 2a, 2b, 2c, 2d it is schematically shown typical maneuvers
that can be performed using a system of command and actuation of boats using bow and
stern waterjets, such as those illustrated in the attached Figure 1, with arrows A
it is indicated the direction of thrust and with arrows B, it is indicated the direction
of displacement of boat 10.
[0012] In this context it is included the solution proposed according to the present invention,
which proposes an improved water-jet, equipped with a system of automatic deletion
of scaling and other materials which accumulate in it, greatly improving the performance
and useful life of the water-jet itself.
[0013] These and other results are obtained according to the present invention proposing
a water-jet which provides a bronze screw, which turns due to the action of water
and which eliminates all scaling (fouling) from the water-jet itself.
[0014] The proposed technical solution according to the present invention is best identified
in the attached independent claim 1.
[0015] Further technical features of the water-jet according to the invention are described
in the following dependent claims.
[0016] The present invention will be now described, for illustrative but not limitative
purposes, according to its preferred and illustrative, but not limitative, embodiments,
with particular reference to the figures of the attached drawings, in which:
- Figure 1 shows schematically a boat provided with control and drive system with bow
and stern water-jet thrusters, according to the prior art;
- Figures 2a, 2b, 2c and 2d show schematically the movement of a boat provided with
the control system as showed in Figure 1, according to the prior art;
- Figure 3 is a horizontal sectional view of a first embodiment of an improved water-jet
according to the present invention;
- Figure 4 is a horizontal sectional view of a second embodiment of an improved water-jet
according to the present invention.
[0017] With particular reference to Figures 3 and 4 of the attached drawings, two improved
water-jets according to the present invention, which can be used, for example, in
the drive system of Figure 1, are generally indicated by numbers 30 and 40.
[0018] The two water-jets 30, 40 are substantially structurally identical to each other
and they constitute, respectively, a seawater intake water-jet 30 and a thrust water-jet
40.
[0019] The water-jet 30 shown in the attached Figure 3 comprises an inlet water conduit
31, from which the water enters, through the opening 39, according to the direction
of the arrows C, and a diaphragm valve 32, comprising a return spring 33, with holes
34 to enter in the water duct 35, inside which is provided an endless screw 36, which
rotates about a shaft 37.
[0020] In practice, the water entering into the opening 39, moving along the direction and
the orientation of the arrows C, moves the diaphragm 38 of the valve 32, overcoming
the force of spring 33, and passes through the holes 34 to enter into the water duct
35.
[0021] The rotation of the endless screw 36, caused by the water pressure, determines the
removal, by scraping, of the scaling (fouling) and any other bodies, so that the water-jet
is always clean; preferably, said screw 36 is made of metal material such as bronze,
and, moreover, the duct 35 is conical in shape, in order to increase the thrust of
the water.
[0022] Again preferably, the pump 8 of the drive system illustrated in Figure 1 is a pump
which allows grinding the residues caused by the cleaning work of the endless screw
36.
[0023] With particular reference to the attached Figure 4, in the water-jet 40 the water
comes out from the holes 44 moving along the direction of arrows D through the outlet
water conduit 41, thus obtaining a thrust effect as shown in Figures 2a, 2b, 2c, 2d.
[0024] In this case, the water duct 45, from which the water comes, has a cylindrical section
(and not conical as in the case of the water duct 35) and, obviously, the diaphragm
48 valve 42 is mounted in the opposite direction with respect to the valve 32 of Figure
3, i.e. it is mounted according to the direction of passage of the water.
[0025] For the rest, the water-jet 40 is structurally equal to the water-jet 30 and it includes
a return spring 43, which is provided inside the valve 42, holes 44 which allow the
water to enter into the outlet water conduit 41, an opening 49 which puts in communication
the valve 42 with the water duct 45, and an endless screw 46, which rotates about
a shaft 47, which is provided inside the water duct 45.
[0026] From the above description the technical characteristics of the improved water-jet,
which is the object of the present invention, are clearly outlined as well as the
advantages are clear too.
[0027] It should be noted, however, that the present invention has been described, for illustrative
but not limitative purposes, according to its preferred embodiments, but it is to
be understood that variations and/or modifications may be made by those skilled in
the art without departing from the scope protection as defined in the attached claims.
1. Improved water-jet drive (30, 40), in particular for driving or maneuvering boats
(10), comprising an inlet water conduit (31) and/or an outlet water conduit (41) which
communicates, through at least one first hole or opening (39, 44), with at least one
valve (32, 42) and, through at least one second hole or opening (34, 49), with at
least one water duct (35, 45), said water jet drive (30, 40) being characterized in that an endless screw (36, 46) is placed inside said duct (35, 45), said screw being able
to rotate thanks to the water action and having a profile and/or a pitch so as to
automatically remove fouling and similar from the inside of the water-jet drive (30,
40).
2. Water-jet drive (30, 40) according to claim 1, characterized in that said endless screw (36, 46) is made of metallic material, such as bronze.
3. Water-jet drive (30, 40) according to claim 1, characterized in that said endless screw (36, 46) is connected to a central shaft (37, 47).
4. Water-jet drive (30, 40) as claimed in at least one of the previous claims, characterized in that said duct (35, 45) has a tapered or cylindrical section.
5. Water-jet drive (30, 40) as claimed in at least one of the previous claims, characterized in that said valve (32, 42) is a diaphragm valve (38, 48) and is provided with at least one
return spring (33, 43).
6. Drive and control system for boats (10), characterized in that said system is provided with a plurality of water-jet drives (1, 2, 3, 4) which are
made according to at least one of claims 1 to 4.
7. System according to claim 6, characterized in that said system includes at least one motor (7), connected to at least a diaphragm pump
(8) and to a valve assembly (6).
8. Boat (10) with a drive and control system according to claim 6.