U.S. patent application number 10/500056 was filed with the patent office on 2005-03-31 for arrangement for steering a water-craft.
Invention is credited to Salmela, Olli, Sirvio, Jari.
Application Number | 20050070179 10/500056 |
Document ID | / |
Family ID | 8563104 |
Filed Date | 2005-03-31 |
United States Patent
Application |
20050070179 |
Kind Code |
A1 |
Sirvio, Jari ; et
al. |
March 31, 2005 |
Arrangement for steering a water-craft
Abstract
The invention relates to an arrangement for steering a
water-craft, which comprises at least one main propulsion device
which is arranged to push the water-craft forward or backward, and
a number of steering propulsion devices, the pushing direction of
which can be changed. The steering propulsion devices are arranged
in the aft of the water-craft on both sides of the said at least
one main propulsion device so that the steering of the water-craft
is continuously provided by means of the steering propulsion
devices without any separate rudder means or the like to be
functionally connected to said at least one main propulsion
device.
Inventors: |
Sirvio, Jari; (Turku,
FI) ; Salmela, Olli; (Turku, FI) |
Correspondence
Address: |
SMITH-HILL AND BEDELL
12670 N W BARNES ROAD
SUITE 104
PORTLAND
OR
97229
|
Family ID: |
8563104 |
Appl. No.: |
10/500056 |
Filed: |
June 23, 2004 |
PCT Filed: |
January 10, 2003 |
PCT NO: |
PCT/FI03/00018 |
Current U.S.
Class: |
440/53 |
Current CPC
Class: |
B63H 2005/1254 20130101;
B63H 25/42 20130101; B63H 5/125 20130101 |
Class at
Publication: |
440/053 |
International
Class: |
B63H 005/125 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 6, 2002 |
FI |
20020243 |
Claims
1. An arrangement for steering a water-craft (1), which comprises
at least one main propulsion device (3, 3a, 3b, 11, 11a, 11b, 11c),
which is arranged to push the water-craft (1) forward or backward,
and a number of steering propulsion devices (2), the pushing
direction of which can be changed, characterized in that the
steering propulsion devices (2) are arranged in the aft of the
water craft (1) on both sides of the said at least one main
propulsion device (3, 3a, 3b, 11, 11a, 11b, 11c) so that the
steering of the water-craft (1) is continuously provided by means
of the steering propulsion devices (2) without any separate rudder
means of the like to be functionally connected to said at least one
main propulsion device (3, 3a, 3b, 11, 11a, 11b, 11c).
2. An arrangement according to claim 1, characterized in that there
is an even number of the steering propulsion devices (2) and the
propeller part of the steering propulsion devices (2) is
stationarily located outside of the hull of the water-craft
(1).
3. An arrangement according to claim 1 or 2, characterized in that
a propeller (3, 3a, 3b) or a water-jet device (11, 11a, 11b, 11c)
functions as the main propulsion device.
4. An arrangement according to any of the preceding claims,
characterized in that the at least one main propulsion device (3,
3a, 3b, 11, 11a, 11b, 11c) of the water-craft (1) is located
essentially in the aft centre part of the watercraft (1) and the
steering propulsion devices (2) are located essentially in the
lateral parts of the aft of the water-craft (1).
5. An arrangement according to any of the preceding claims,
characterized in that the output required by the steering
propulsion devices (2) is in all less than 50% of the common shaft
output of the said at least one main propulsion device (3, 3a, 3b,
11, 11a, 11b, 11c) and of the steering propulsion devices (2).
6. An arrangement according to any of the preceding claims,
characterized in that said at least one main propulsion device (3,
3a, 3b) is connected by means of a shaft (5) to a prime mover (4),
which prime mover (4) can be e.g. one or more diesel and/or
electric engines and/or gas turbines.
7. An arrangement according to any of the preceding claims,
characterized in that the steering propulsion devices (2) are
arranged to be installed under the cargo space (10) of the
water-craft (1).
8. An arrangement according to claim 7, characterized that the
steering propulsion devices (2) are arranged to be installed to the
water-craft (1) so that a space (8) is formed under the cargo space
(10) for the maintenance of the steering propulsion devices (2).
Description
[0001] The invention relates to an arrangement for steering a
water-craft, which comprises at least one main propulsion device,
which is arranged to push the water-craft forward or backward, and
a number of steering propulsion devices, the pushing direction of
which can be changed, in accordance with the preamble of claim
1.
[0002] Water-crafts or vessels mean here all kinds of marine
vessels, like for example cruisers, passenger ships, ice breakers
and different cargo ships. Arrangements are already known, in which
a water-craft is provided with two mechanically connected
propellers with rudders behind them, two or three separate
pod-propulsion devices or a propeller, behind which there is a
contra-rotating propeller in a pod-propulsion device. The last
mentioned has been disclosed in a WO-publication 01/54971, in which
the pod-propulsion unit has been indicated by the reference numeral
4 and the propeller by numeral 3.
[0003] The prior art solutions include substantial disadvantages.
Firstly, the mechanical propeller arrangement has long shaft lines
and shaft supports outside the hull of water-craft, which lead to a
non-uniform wake field.
[0004] Steerable rudder-propeller devices or pod-propulsion devices
have become more general in water-crafts. Since these devices are
turnable, their thrust force can be utilized for steering of the
water-craft.
[0005] A disadvantage with an electric arrangement of two or more
pod-propulsion devices are the high costs, because efficient
pod-propulsion devices require engine-driven generators together
with their power control systems. These are expensive, heavy and
large. For instance in RoRo vessels handling of cargo becomes more
difficult because of the engine rooms and gaps required by the
machinery, since these are partly located above the cargo deck.
This means that several disadvantageous narrow parts are formed in
the cargo space, whereby the rear end of the cargo space remains
narrow. The heavy electric machinery leads further to a
disadvantageous location of the displacement's centre of gravity in
the longitudinal direction.
[0006] In the contra-rotating pod/propeller-combination there is
only one steering device, which is often considered as a
disadvantage from the viewpoint of reliability.
[0007] An object of the present invention is to eliminate the
drawbacks of the prior art and to provide a novel solution
advantageous as to its costs and enabling, where applicable, better
utilization of the cargo space of the water-craft
[0008] The aims of the invention can be achieved as is disclosed in
claim 1 and in the other claims. According to the invention the
steering propulsion devices are arranged in the aft of the water
craft on both sides of the said at least one main propulsion device
so that the steering of the water-craft is continuously provided by
means of the steering propulsion devices without any separate
rudder means of the like to be functionally connected to said at
least one main propulsion device.
[0009] The invention is based on the use of turnable steering
propulsion devices in a water-craft so that they alone provide
steering and additionally they participate in moving the
water-craft forward. A major part of the forward or backward
propulsion is generated by a separate thrust device e.g. a large
propulsion unit or large propulsion units. An important advantage
of the solution according to the invention is the fact that the
upper end of the pod-propulsion devices fits below the cargo deck.
Since the fully electric machinery of conventional large
pod-propulsion devices is heavier and larger than the machinery to
be utilized according to the invention, the invention allows for
increased cargo capacity and handling of cargo becomes more
efficient and easier. Furthermore, the solution is more economic
and easier to put technically into practice than the known
solutions. The cargo deck can be lowered, the dimensions of the
water-craft can be more economic and, compared with one centre
propulsion device, two propulsion devices provide better
reliability, which is important especially for the manoeuvrability
of a passenger ship. Further, when separate main propulsion devices
and steering propulsion devices are provided no supplementary
output is used unnecessarily in manoeuvring.
[0010] According to the invention there is an even number of the
steering propulsion devices and the propeller part of the steering
propulsion devices is stationarily located outside of the hull of
the water-craft. There is one or more main propulsion devices and
for instance a propeller or a water-jet device may function as the
main propulsion device.
[0011] The water-craft's at least one main propulsion device is
located essentially in the aft centre part of the water-craft and
the steering propulsion devices are positioned to the sides of the
propulsion device being thus located in the lateral parts of the
water-craft near the sideboards thereof. A high efficiency is
obtained when the main propulsion device is placed as far as
possible in the water-craft's aft and no protruding parts
increasing the resistance are needed in the rear side of the main
propulsion device. Since no shaft bearings are needed, a uniform
wake is created. The steering propulsion devices provide an
excellent manoeuvrability even in rough weather conditions, also at
low speeds for instance less than 5 knots.
[0012] According to the invention, the output of the steering
propulsion devices need not be high. The output required by the
steering propulsion devices is less than 50% of the common shaft
output of the main propulsion device and of the steering propulsion
device. Shaft output means here the usual output obtained from the
devices at maximum i.e. the nominal output taken by the main
propulsion device and the steering propulsion device, which can be
measured from the outlet shaft of the device. The propulsion device
itself is connected by means of a horizontal or almost horizontal
shaft or shafts to a prime mover that may comprise one or more
diesel engines and/or electric engines and/or gas turbines.
[0013] Further, since the steering propulsion devices are installed
on both sides of the one or more main propulsion devices
substantially near the outboard of the water-craft, they can be
relatively small and can thus be installed under the cargo space of
the water-craft. By doing so, a space can be formed under the cargo
space for the maintenance and inspection of the steering propulsion
devices.
[0014] Also other alternative solutions are conceivable, in which
there can be in the middle one or more water-jet devices as a main
propulsion device e.g. if the speed of the water-craft is high.
Also in this case, the steering propulsion devices are at the side
and a major part of the power used for moving forward is provided
by the main propulsion device.
[0015] In the following the invention is described by way of
example only with reference to the accompanying drawings, in
which
[0016] FIGS. 1A and 1B show a water-craft provided with an
arrangement according to the invention as a side view and viewed
from below,
[0017] FIGS. 2A and 2B show alternative solutions relating to main
propulsion devices and steering propulsion devices, and
[0018] FIGS. 3A and 3B show further alternative solutions relating
to main propulsion devices and steering devices.
[0019] According to FIGS. 1A and 1B, the arrangement is formed by a
water-craft or a vessel 1 together with steering propulsion devices
2 and a main propulsion device 3. In this solution, the steering
propulsion devices, even in number, have been placed quite close to
the outboard 6 of the vessel. Diesel engines, indicated by the
reference numeral 4, serve as prime mover for the main propulsion
device, the output of which is transferred to the main propulsion
device by means of a shaft 5. As the steering propulsion devices in
the solution according to the invention need not be large, they do
not require much space and the maintenance space 8 they need, in
which maintenance staff 7 may go for checking, and when required,
repairing the steering propulsion devices, is situated
advantageously below the cargo space 10. In this way the whole
cargo space can be put into use and there are no previously needed
narrowing parts, but the whole area can be utilized at maximum e.g.
by loading onboard trucks and other cargo on wheels 9.
[0020] In FIG. 2A, the upper view shows a main propulsion device 3
and a steering propulsion device 2. Furthermore, a couple of
examples of a steering propulsion device is shown in different
positions 2a and 2b. When the steering propulsion device is in
position 2b, turning of the vessel into a desired direction is
provided. If there is a need for boosting the turning, also the
other steering propulsion device 2 is turned, respectively, into
position 2b simultaneously with the previous one. In FIG. 2B, one
main propulsion device 3 has been replaced by two separate main
propulsion devices 3a and 3b.
[0021] In FIG. 3A, in addition to the steering propulsion devices
2, there is provided an alternative solution to the traditional
propeller and in this view a water-jet device 11 is used as a main
propulsion device. The FIG. 3B view is a supplementary variation of
the FIG. 3A, in which there are more than one water-jets, in this
solution three water-jets 11a, 11b and 11c. Advantageously, also
two water-jets 11a and 11c can be installed.
[0022] Within the scope of invention; solutions also differing from
the above described are feasible. The solution can be applied to
all kinds of water-crafts.
[0023] For example, in war ships and cruisers the solution makes
possible a diversified driving profile. The main mover of the
steering propulsion devices can also be placed above the cargo deck
e.g. around the smoke stack, in which case supplying of electricity
also to other parts of the vessel is easy. In cruisers, this makes
possible flexible distribution of electric power between the hotel
load and the propulsion devices.
[0024] It is clear to the one skilled in the art that the invention
is not restricted to the embodiments described above, but different
applications thereof are feasible within the inventive idea defined
by the ensuing claims.
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