JP2010064740A - Propulsion and steering arrangement - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a propulsion and steering arrangement having improved propeller efficiency. <P>SOLUTION: The propulsion and steering arrangement for a vessel has a screw propeller 2, and a rudder 10 arranged behind the propeller. A fairing 6 at a tail end of the propeller and a bulb-shaped body 20 provided on the rudder form a streamlined body, which is continuous except for a narrow gap between the fairing and the bulb-shaped body. The rudder has a twisted upper leading edge 12 extending from an upper side end of the rudder to the bulb-shaped body and a twisted lower leading edge 13 extending from a lower side end of the rudder 10 to the bulb-shaped body. At least one of the upper leading edge and the lower leading edge has a constant twist angle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vessel propulsion steering apparatus. This device has a propeller, a rudder disposed behind the propeller, and a valve-shaped main body installed on the rudder.

The most common means of propelling a ship is a screw propeller with two or more propeller blades. In order to suppress fuel consumption and emission, the propulsion efficiency of the propeller, which is determined by the ratio between the propulsive force (also referred to as effective output) and the obtained output, needs to be increased as much as possible.

  Usually, the prediction of propulsion efficiency for a certain engine output is made through a model scale test. The dominant idea of conducting model tests at that time, developed more than 100 years ago, suggests that ship propellers and hulls be reviewed and evaluated separately. In practice, however, the interaction between the propeller and the hull is extremely important. In order to obtain the optimum characteristics, it is necessary to integrate the propeller and the hull and to adjust them both. This is also true for the interaction between the propeller and hull accessories such as the rudder.

  In order to improve the interaction between the screw propeller and the rudder, German patent GB 762,445 shows that a valve-like body is arranged behind the propeller in the direction of extension of the propeller shaft. In order to avoid contraction of the propeller slip flow, it has been proposed to press the open projecting head of the valve-like body closer to the rear end of the propeller blade and overlap the propeller hub. In one embodiment, the front part of the valve-like body is supported by an unbalanced rudder rudder post, the rear or stern part of the valve-like body is carried by a rudder blade, and both parts of the valve-like body are connected jointly. Is done. In another embodiment, the valve-like body is carried by a balance rudder, and the propeller hub has a recess that fits into the protruding head of the valve-like body so that when the rudder blade rotates, the propeller hub The movement of the swing of the valve-shaped body with respect to is possible.

  European Patent Application No. 0852551A shows a marine propulsion steering device in which a transition ring screwed to the hub of a screw propeller forms a continuous streamlined body, and a valve-like body is a propeller. Behind, it is supported by a rudder horn of a half spade rudder. The streamlined body is only broken by a narrow rotation gap between the transition ring and the valve-like body.

  International Publication No. WO2006 / 112787A shows a propulsion steering device for a ship, and a fairing hub cap is integrated with a screw propeller hub and is supported by a full spade rudder behind the propeller. At the same time, a continuous streamlined body is formed. The front end of the valve-shaped body and the hub cap are designed such that the narrow gap between the valve-shaped body and the hub cap is maintained constant when the rudder rotates. The rudder also has a highly refined shape based on simulation and optimization of the shape of the torsion tip, which is the swirl water that is propelled by the propeller when the ship is driven forward by the propeller. collide. The twist angle of the rudder is greatest in the region of the valve-shaped body and decreases with the distance from the valve-shaped body. The torsional tip profile of the rudder improves the propeller slip flow flowing in the rudder region, thereby improving propulsion efficiency.

European Patent Application No. 0852551A International Publication No. WO2006 / 112787 Pamphlet

  The object of the present invention is to improve the propulsion steering apparatus shown in European Patent No. 0852551A and International Publication No. WO2006 / 112787A.

In the first aspect of the present invention,
Provided is a marine propulsion steering apparatus having a screw propeller and a rotatable rudder disposed behind the propeller. A streamlined body is formed by the fairing at the rear of the propeller and the valve-shaped body provided on the rudder, except for the narrow gap between the fairing and the valve-shaped body. Is continuous. The rudder has a torsion upper tip extending from the upper end of the rudder to the valve-shaped body, and a twisted lower tip extending from the lower end of the rudder to the valve-shaped body. The rudder is characterized in that at least one of the upper tip and the lower tip has a constant twist angle, which is compared to the sophisticated solution shown in WO 2006 / 112787A. It is possible to manufacture a rudder that is strong and easy.

  Applicants have found that the fuel consumption of the propulsion steering device of the present invention can be reduced compared to a conventional propulsion steering device having a non-twisted tip profile, such as European Patent Application 0852551A.

  Although not anticipated by the applicant, the propulsion steering device according to the present invention is shown in International Publication No. WO2006 / 112787A where the twist of the rudder is from the region of the valve-shaped body, the upper end of the rudder or As with conventional propulsion steering devices that decrease towards the lower end, fuel can be saved. In the propulsion steering device of International Publication No. WO2006 / 112787A, when the rudder is parallel to the rotation axis of the propeller, the theoretical propulsion efficiency tends to be high, but when the rudder rotates and the ship is steered, The propulsion efficiency tends to be higher in the propulsion steering apparatus according to the present invention. Often, the actual overall propulsion efficiency and fuel consumption are substantially equal in both propulsion steering devices, considering that the rudder of the ship is operated in the sea area and counters oncoming winds and currents. In the case of more maneuvers, the overall propulsion efficiency and fuel consumption are better in the propulsion steering device according to the invention.

  The propulsion steering apparatus according to the present invention has the additional advantage that the production cost of a rudder having a constant twist angle is reduced compared to the rudder of WO 2006 / 112787A.

  Both the upper tip and the lower tip preferably have a constant twist angle.

  The at least one twist angle is preferably less than 15 °, the twist angle is more preferably less than 10 °, and even more preferably between 5 ° and 10 °.

  The at least one twist angle decreases in the stern direction to 0 ° within a range defined by each tip and the pivot axis of the rudder.

  The valve-shaped body is disposed on the rudder blade of the rudder, which allows the valve-shaped body to swing with respect to the fairing when the rudder blade rotates. . The rudder may be a full spade rudder or a half spade rudder.

  The propulsion efficiency and fuel savings of the propulsion steering device according to the present invention are such that the propeller's turning axis moves further away from the rudder tip, or the upper and lower tips of the rudder are at a given rotation angle of the rudder. It becomes more remarkable as it deviates from the rotation axis. For this reason, the turning axis of the rudder is preferably arranged at a position 30% to 50% of the maximum rudder length from the upper or lower tip in the stern direction, and more preferably 35% to 50% of the maximum rudder length. %, More preferably 40% to 50% of the maximum rudder length.

  In a second aspect of the present invention, a ship having a propulsion steering apparatus having the above-described characteristics is provided.

1 is a diagram showing a propulsion steering apparatus according to a first embodiment of the present invention. FIG. 2 is a view showing the rudder of FIG. 1 together with top and bottom cross sections. FIG. 3 is a view showing an upper cross section of FIG. FIG. 3 is a view showing a bottom section of FIG. FIG. 5 is a view showing a propulsion steering apparatus according to a second embodiment of the present invention attached to the stern of a ship.

  Hereinafter, the present invention will be described in detail with reference to FIGS. In the drawings, preferred embodiments of the invention are shown.

(First embodiment)
1 to 4 show a propulsion steering apparatus according to a first embodiment of the present invention. The propulsion steering device is attached to the stern of the ship. The ship may be equipped with one or more propulsion steering devices.

  As shown in FIG. 1, the propulsion steering apparatus according to the first embodiment includes a screw propeller attached to a drive shaft (not shown) of a ship, and a full spade rudder 10, At the position of the pivot axis P, it is attached to the rudder stock (not shown) of the ship behind the rear end of the propeller 2. In the present application, the term “rear” is expressed with reference to the forward direction of the ship, as indicated by the arrow F.

  When the propeller 2 is driven by the drive shaft, the propeller 2 propels the ship in either the forward direction F or the reverse stern direction. When the ship is propelled in the forward direction F by the propeller 2, the water that has passed through the propeller 2 forms a slip flow of swirl water, and this flow proceeds in the direction of the rudder.

  The propeller 2 has a hub 4 on which three propeller blades 8 are installed. Note that the number of blades may be larger or smaller. Although the propeller 2 is shown as a variable pitch propeller, it may be a fixed pitch.

  The rear part of the propeller 2 is defined by a fairing hub cap 6, which is screwed or compressed to the propeller hub 4 and integrated with the hub 4. Also, the outer profile of the propeller hub 4 shown may be formed from a single part. The fairing hand cap 6 has a recess. The concave portion is fitted to the front end portion 22 of the valve-shaped main body 20, and the valve-shaped main body 20 is attached to the rudder blade 10a of the rudder 10 by a flange joining means and integrated with the rudder blade 10a.

  The front end 22 of the valve-shaped body 20 enters the recess of the hub cap 6, but does not contact the recess. The concave portion of the hub cap 6 and the front end portion 22 of the valve-shaped main body 20 are curved, and when the rudder 10 rotates, there is a certain narrowness between the concave portion of the hub cap 6 and the front end portion 22 of the valve-shaped main body 20. The gap is maintained. The valve-shaped main body 20 and the hub cap 6 form a continuous streamline type main body, which is divided only by a narrow gap. The streamlined main body prevents the contraction of the propulsion slip flow, thereby improving the propulsion efficiency.

  Hereinafter, the shape of the rudder 10 will be described in more detail with reference to FIGS. In FIG. 2, the full spade rudder 10 of FIG. 1 is shown with an upper cross section at the upper end 17 of the rudder 10 and a bottom cross section at the lower end 18 of the rudder 10. 3 and 4 show the top and bottom cross sections in more detail.

  As shown in FIGS. 2 to 4, the rudder 10 has a streamlined profile, and has an upper end 12 extending from the upper end 17 of the rudder blade 11 to the valve-shaped body 20, and a lower end 18 of the rudder blade 11. And a rear edge 15 extending from the upper end 17 to the lower end 18 of the rudder 10 at the rear of the valve-shaped main body 20. The upper tip 12 has a constant first twist angle α, which is 8 ° in the left rudder direction with respect to the center line C of the rudder 10. On the other hand, the lower tip 13 has a constant twist angle β, which is 6 ° in the right rudder direction with respect to the center line C of the rudder 10. The twist angles α, β may be different values, but are preferably less than 15 ° for each direction.

  The torsion of the upper and lower tips 12, 13 shown is reduced to 0 ° in the stern direction within the range defined by each tip 12, 13 and the pivot axis P of the rudder 10. For this reason, the trailing edge 15 is not twisted, and the trailing edge extends along a straight line. Further, the twist may be reduced to 0 ° within a range determined by the pivot axis P and the trailing edge 15, or the twisting may continue until the trailing edge 15 to form a fishtail rudder.

  When the ship is driven in the forward direction F by the propeller 2, the torsional tips 12 and 13 collide with the spiral water propelled backward by the propeller 2. The twisted tip profile of the rudder 10 improves the propeller slip flow through the rudder region, which improves propulsion efficiency.

  As best shown in FIG. 1, the turning axis P of the rudder 10 shown is installed at a position about 45% of the maximum rudder length L from the upper tip 12 in the stern direction. Further, the turning axis P may be arranged at different positions, but is preferably in the range of 35% to 50% of the maximum rudder length L. Thereby, the balance which was excellent in the rudder 10 is obtained.

  When the turning axis P of the indicated rudder 10 is arranged within the range of the aforementioned maximum rudder length L, the positional deviation of the tips 12 and 13 of the rudder 10 from the rotation axis of the propeller 2 When the rotation angle is small, it becomes large. Under such a large misalignment, described in WO 2006/112787, which has a large twist angle near the valve-shaped body and a small twist angle near the upper and lower ends of the rudder. Compared with the conventional tip profile as described above, the propulsion efficiency is increased due to the constant twist angles α and β.

  In addition, the manufacturing cost of the rudder 10 having the constant twist angles α and β is suppressed as compared with the manufacturing cost described in International Publication No. WO2006 / 112787.

(Second embodiment)
FIG. 5 shows a propulsion steering apparatus according to a second embodiment of the present invention attached to the stern of a ship.

  As shown in FIG. 5, the propulsion steering apparatus according to the second embodiment has a screw propeller 2 attached to the drive shaft 30 of the ship and a half spade rudder 10 ′, and the half spade rudder 10 ′ is a propeller. At the rear of 2 is attached to the hull of the ship. The half spade rudder 10 'has a tip head 10d fixed to the hull and a rotatable rudder blade 10a. On the rudder blade, a valve-shaped main body 20 is flange-connected at a predetermined position.

  A lower main bearing 10e is provided for the tip head 10d. The lower main bearing 10e supports a rudder stock 32, and a rudder blade 10a is attached to the rudder stock.

  The propeller 2 has a hub 4 on which four propeller blades 8 are attached. Note that the number of blades may be larger or smaller. The propeller 2 is shown with a variable pitch, but this may be a fixed pitch.

  The propeller hub 4 is molded as a single part and has a fairing shape. Alternatively, the fairing may be a hub cap that is screwed and fixed to the propeller hub. The hub 4 has a recess, and the recess is fitted so that the tip of the valve-shaped main body 20 does not contact the recess. The valve-shaped body 20 and the hub 4 form a constant streamline-shaped body, which is divided only by a narrow gap and is opposed to the hub 4 when the rudder blade 10a rotates. Swing movement is possible. The streamlined main body prevents contraction of the propeller slip flow, thereby increasing propulsion efficiency. The concave portion of the hub 4 and the front end of the valve-shaped main body 20 are curved, and the narrow gap is kept constant when the rudder blade 10a rotates.

  Similar to the full spade rudder 10 according to the first embodiment, the half spade rudder 10 'according to the second embodiment has a streamlined profile, a twisted upper tip 12, a twisted lower tip 13, and an untwisted, linear And has a trailing edge 15 extending. The upper tip 12 extends from the upper end of the tip head 10d to the lower end of the tip head 10d. The lower tip 13 extends from the lower end 18 of the rudder blade 10a to the valve-shaped body 20. The upper tip 12 has a constant first twist angle in the right rudder direction with respect to the center line of the rudder 10 '. On the other hand, the lower tip 13 has a constant twist angle in the left rudder direction with respect to the center line. The twist angle has a value of less than 15 °, and the twist angle in each direction is more preferably less than 10 °, and even more preferably between 5 ° and 10 °. The twist of the upper tip 12 decreases to 0 ° toward the rudder stock 32 in the stern direction. In the stern direction, the twist of the lower tip 13 decreases to 0 ° within a range determined by the lower tip 13 and the pivot axis P of the rudder blade 10a. The range between the pivot axis P and the trailing edge 15 may be twisted.

  When the propeller 2 drives the ship in the forward direction, the twisted tips 12 and 13 collide with the swirl water propelled backward by the propeller 2. The torsional tip profile of the rudder 10 'improves the propeller slip flow through the rudder region, thereby improving propulsion efficiency.

  The rudder 10 'shown has a constant rudder length in the forward and stern directions. The pivot axis P of the rudder blade 10a is disposed at a position of about 41% from the upper tip and the lower tips 12, 13 in the stern direction. The pivot axis P may be arranged at a different position, but is preferably 35 to 50% of the rudder length, thereby achieving a good balance in the rudder 10 '.

  When the swivel axis P of the indicated rudder 10 'is arranged in the range of the maximum rudder length described above, the displacement of the lower tip 13 of the rudder blade 10a from the rotation axis of the propeller 2 is caused by the rotation of the rudder 10'. When the corner is small, it becomes large. Under such a large misalignment, due to the constant twist angle of the lower tip 13, it has a large twist angle near the notch and a small twist angle near the lower end of the rudder blade. Propulsion efficiency increases compared to the lower tip.

  Also, the manufacturing cost of a half spade rudder 10 'having a constant twist angle is lower than that of a half spade rudder having a different twist angle.

2 Propeller
4 Hub
6 Fairing hand cap
8 Propeller blade
10 Full spade rudder
10 'half spade rudder
10a rudder blade
10d tip head
10e main bearing
12 Top tip
13 Bottom tip
15 trailing edge
18 Lower edge
20 Valve body
22 Front end
30 Drive shaft
32 Rudder stock

Claims (9)

A propulsion steering device for a ship,
A screw propeller and a rotatable rudder disposed behind the propeller;
A streamlined body is formed by the fairing at the rear of the propeller and the valve-shaped body provided on the rudder, except for the narrow gap between the fairing and the valve-shaped body. Is continuous,
The rudder has a torsion upper tip that extends from the upper end of the rudder to the valve-like body, and a twisted lower tip that extends from the lower end of the rudder to the valve-like body,
The propulsion steering apparatus, wherein at least one of the upper tip and the lower tip has a constant twist angle.   The propulsion steering apparatus according to claim 1, wherein both the upper tip and the lower twist tip have a constant twist angle.   The propulsion steering device according to claim 1 or 2, characterized in that at least one twist angle is less than 15 °, preferably less than 10 °, more preferably between 5 ° and 10 °. .   4. The at least one twist angle is reduced to 0 ° in a stern direction within a range defined by each tip and a turning axis of the rudder. Propulsion steering device.   The valve-shaped body is disposed on the rudder blade of the rudder, which allows the valve-shaped body to swing with respect to the fairing when the rudder blade rotates. The propulsion steering apparatus according to any one of claims 1 to 4, characterized in that:   The propulsion steering apparatus according to claim 5, wherein the rudder is a full spade rudder.   The propulsion steering apparatus according to claim 5, wherein the rudder is a half spade rudder.   The turning axis of the rudder is arranged at a position of 30% to 50% of the maximum rudder length from the upper tip or the lower tip in the stern direction, preferably 35% to 50% of the maximum rudder length, more preferably The propulsion steering apparatus according to any one of claims 1 to 7, wherein the propulsion steering apparatus is disposed at a position of 40% to 50% of a maximum steering length.   A ship having the propulsion steering device according to any one of claims 1 to 8.

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