US2910954A - Rudder for boats - Google Patents

Rudder for boats Download PDF

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US2910954A
US2910954A US685898A US68589857A US2910954A US 2910954 A US2910954 A US 2910954A US 685898 A US685898 A US 685898A US 68589857 A US68589857 A US 68589857A US 2910954 A US2910954 A US 2910954A
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rudder
guide member
displacement
boats
disposed
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US685898A
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Uecker Guenter
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B63SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63HMARINE PROPULSION OR STEERING
    • B63H25/00Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
    • B63H25/06Steering by rudders
    • B63H25/38Rudders
    • B63H25/381Rudders with flaps

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  • the present invention relates to a rudder for boats.
  • Rudders for boats which comprise a ruddermember of predetermined profile with a heavy head, the rotating axis of which is disposed within the rudder body and two guide bodies which are disposed in front of said rudder head in order to create a branching effect in the flow on the low pressure side.
  • the two guide bodies which are accommodated in known manner to the direction of flow of the screw-water, project from the upper or lower edge of the rudder to the center of the .screwshaft and connected together by means of a plate or a profile-body.
  • streamlined rudders with wing-like curved pre-profiles disposed symmetrically on both sides of the rudder-head have been proposed before.
  • the preprofiles are rigidly connected with the stern-post frame or forms itself the immovable rudder-stern-post with such formation of the rudder-head and position of the rotating axis of the rudder body relative to the pre-profiles, that the nozzles formed by the latter with the rudder body remain nearly unchanged in each resting position.
  • Stream lined balancing rudders are also known, wherein two wing-like curved pre-profiles are secured to bothsides of the rudder-head symmetrically to its median plane by means of ribs or the like, which pre-profiles are disposed in such a manner, that a wide opening remains between the entering edges, which opening branches off into two nozzle-like, narrowing channels which. run along the rudder-head.
  • Rudder devices which have two auxiliary planes, one of which controls the rudder if moved in one direction, while the other controls the rudder if it is moved in the opposite direction.
  • the auxiliary pressure-planes are brought, thereby, automatically into such a position, that they support the main-rudder.
  • All known rudder structures for boats with a guide body disposed in front of the rotating axis of the rudder permit of movement of the boat in a more or less large turning circle only.
  • the radius of the turning circle depends heavily upon the velocity with which the boat moves. Just when in a narrow space the best turn is required, is it necessary to move slowly for safety reasons, so that thereby the rudder-effect is appreciably reduced. In order to bring about in such a case a better turn, it is often necessary for turning in narrow spaces to shift from forward movement to rearward movement, so that the shifting mechanism is subjected to great wear.
  • the distance wardly beyond the rudder-shaft. between the center of the rudder shaft to the front edge of the guide member is one-third of the diameter of the screw.
  • the abutments limit the displacement of the guide member on both sides to about 15 to 20.
  • the balance of the rudder and a minimum ruddermoment is brought about by immediate abutment of the guide member outwardly at the smallest rudder-angles.
  • This rudder permits of practically the quietest control with far-reaching elimination of the cross-force of the screw at an extremely small rudder moment.
  • a vehicle equipped with this rudder shows also during a back-up movement a good maneuverability towards both sides.
  • the guide members have for instance a round nose and run rearwardly sharply in a straight line.
  • the lateral distance of the guide member is approximately equal with the profile height of the main rudder.
  • the profile height of the guide members is about one-fifth to one-tenth of their length.
  • Figure 1 is a side elevation of a rudder for boats, using a one-plane main rudder
  • Fig. 2 is a section along the lines 2--2 of Fig. 1;
  • Fig. 3 shows schematically the flow conditions in the case when the control rudder is set for starboard of 45;
  • Fig. 4 shows schematically the flow conditions in the case, when the control rudder is set for port of Fig. 5 is a side elevation of the device with a boxrudder;
  • Fig. 6 is a section along the lines 6-6 of Fig. 5;
  • Fig. 7 shows schematically the flo'w conditions in the case, when the control rudder of Fig. 5 is set for starboard of 45
  • Fig. 8 shows schematically the flow conditions in the case, when the control-rudder of Fig. 5 is set for port of 90";
  • Fig. 9 is a side elevation of the control-rudder with two fins
  • Fig. 10 is a section along the lines 10-10 of Fig. 9;
  • Fig. 11 shows schematically the flow conditions in the case, when the control-rudder of Fig. 9 is set for star board of 45 and Fig. 12 shows schematically the flow conditions in the case, when the control-rudder of Fig. 9 is set for per of 90.
  • the main-rudder 3 and box-rudder 9, respectively, which are swingably mounted by means of the rudder-shaft 2 at the stern of the ship behind the ship-screw 1, has a lower end face 4 as well as an upper end face 5, which faces 4 and 5 project forwardly beyond the rudder-shaft 2.
  • the shaft or shafts 6 of the guide member 7 are swingably mounted therein, and the displacement of the guide member 7 is limited by abutment members 8 which are disposed on the end faces 4, 5 and by the inner walls of the box-rudders 9, respectively.
  • the guide member 7 is arranged between the lower and upper end faces, which project forwardly beyond the rotating axis of the rudder 9 in such a manner, that it penetrates partly with its rear end into the box-like two-plane rudder, in order to achieve a good abutment and a good stabilization by two-sided water pillows.
  • the rotating axis 6 of the guide member 7 may be disposed in accordance with the requirements up to about one-fifth of the length of the front edge.
  • the distance between the two inner walls of the boxlike two-plane rudder 9 depends upon the angle of displacement of the guide member. This angle amounts in accordance with the requirements for the rudder, to about 15 to 45 towards each side.
  • the larger displacement angles of the guide member create, for instance, in hard rudder positions greater cross-forces, while smaller displacement-angles bring about more favorable ruddermoments with small rudder angles.
  • the distance between the rotating axis 2 of the rudder to the rear edge of the box-like, two-plane main rudder should amount to at least one-half of the diameter of the screw, but must be so big, that an overbalance is avoided.
  • the guide member may comprise two fins 7, (Fig. 10), each of Which may swing upon axles 6 disposed laterally and symmetrically to the longitudinal median plane of the rudder-blade 3, the distance between the axles 6 being smaller than the depth of the fins in the initial direction of the flow.
  • the abutments are preferably arranged in such a manner, that the inner face of the fins 7 which are directed away from the initial direction of the flow in its final displacement forms an angle of about with the symmetrical plane of the rudder and that the fin directed towards the direction of flow forms a displacement at a rudder displacement of over 45 towards the first mentioned fin.
  • the angle of the inward displaced guide members to the symmetrical plane is about 120 and 60, respectively.
  • the effect of the rudder designed in accordance with the present invention is based on the fact that the screw stream is brought on the low pressure side of the rudder up to a displacement of 90 into engagement and is shifted over between the two faces of the box-rudder, respectively, by means of a guide member, which is swingably disposed in front of the rotating axis within the rudder body, self-adjustable by the screw stream and limited in its movement by an abutment.
  • the rudder moment is smaller and more evenly distributed over the entire range of displacement of the rudder than with any other rudder. Since the rudder operates effectively just at slow speed, the use of a maneuver with full force at suddenly occurring difficulties in narrowest space is widely eliminated.
  • a steering rudder for ships having a guide member, including a driving screw, a first vertical axle for rotatable mounting of said rudder and at least one second vertical axle for rotatable mounting of said guide member, said second axle being disposed parallel to and, in the direction of movement of said ship, in front of said first axle, and abutment means connected with said rudder and limiting the angular displacement of said guide member towards both sides from a central normal position, and said rudder having beam-like upper and lower end faces projecting forwardly beyond said first vertical axle andsaid second vertical axle being rotatably mounted in said upper and lower end faces of said rudder.
  • rudder as set forth in claim 1, wherein said rudder is formed as a box-like two-plane rudder and the forward edge of the latter is disposed in one line with said first rotating axle of said rudder, and said guide member projects partly into said box-like rudder and the inner faces of the latter limit the angular displacement of said guide member to an angular range of about 15 to 45 towards each side from a normal, central position.
  • said guide member comprises two fins rotatable upon axles disposed laterally and symmetrically to the longitudinal median plane of said rudder, the distance between said axles being less than the depth of said fins taken in the initial direction of flow.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Toys (AREA)
  • Fittings On The Vehicle Exterior For Carrying Loads, And Devices For Holding Or Mounting Articles (AREA)

Description

Nov. 3, 1959 G. L-IECKER 2,910,954
' RUDDER FOR BOATS Filed Sept. 24, 1957 3 Sheets-Sheet 1 INVEN T07? G6ner UECKER NOV. 3, 1959 UECKER 2,910,954
RUDDER FOR BOATS I Filed Sept. 24, 1957 3 Sheets-Sheet 2 HI 9 'w ilil INVENTOP GOnfer UECK ER Nov. 3, 1959 s. UECKER RUDDER FOR BOATS S Sheets-Sheet 3 Filed Sept. 24, 1957 IN VEN T01? 60/1 in UECKER United States Patent RUDDER FOR BOATS Guenter Uecker, Rendsburg, Germany Application September 24, 1957, Serial No. 685,898
Claims priority, application Germany September 28, 1956 7 Claims. (Cl. 114-167) The present invention relates to a rudder for boats.
Rudders for boats are known which comprise a ruddermember of predetermined profile with a heavy head, the rotating axis of which is disposed within the rudder body and two guide bodies which are disposed in front of said rudder head in order to create a branching effect in the flow on the low pressure side. The two guide bodies, which are accommodated in known manner to the direction of flow of the screw-water, project from the upper or lower edge of the rudder to the center of the .screwshaft and connected together by means of a plate or a profile-body.
Furthermore, streamlined rudders with wing-like curved pre-profiles disposed symmetrically on both sides of the rudder-head have been proposed before. If the rudder is designed as a non-balancing rudder, the preprofiles are rigidly connected with the stern-post frame or forms itself the immovable rudder-stern-post with such formation of the rudder-head and position of the rotating axis of the rudder body relative to the pre-profiles, that the nozzles formed by the latter with the rudder body remain nearly unchanged in each resting position. Stream lined balancing rudders are also known, wherein two wing-like curved pre-profiles are secured to bothsides of the rudder-head symmetrically to its median plane by means of ribs or the like, which pre-profiles are disposed in such a manner, that a wide opening remains between the entering edges, which opening branches off into two nozzle-like, narrowing channels which. run along the rudder-head.
Rudder devices are also known which have two auxiliary planes, one of which controls the rudder if moved in one direction, while the other controls the rudder if it is moved in the opposite direction. The auxiliary pressure-planes are brought, thereby, automatically into such a position, that they support the main-rudder.
All known rudder structures for boats with a guide body disposed in front of the rotating axis of the rudder permit of movement of the boat in a more or less large turning circle only. Furthermore, the radius of the turning circle depends heavily upon the velocity with which the boat moves. Just when in a narrow space the best turn is required, is it necessary to move slowly for safety reasons, so that thereby the rudder-effect is appreciably reduced. In order to bring about in such a case a better turn, it is often necessary for turning in narrow spaces to shift from forward movement to rearward movement, so that the shifting mechanism is subjected to great wear.
Since a rudder reaches its highest control effect normally at an angular displacement of 45, attempts have been made and results have been nearly achieved, by which the current reaches engagement at the low pressure side up to said angular displacement, so that an improvement of the normal rudder seemed hardly possible.
A turning on the place was hitherto impossible with'a normal rudder. For this reason, special drives have been developed for this purpose, which permit of the best maneuverability, yet which bring about other drawbacks.
It is, therefore, one object of the present invention to provide a rudder which confers to a boat with normal screw-drive the maneuverability of a special drive and particularly permits of a turning on its place.
It is another object of the present invention to provide a rudder arrangement which includes a guide member, the angular displacement of which is limited in both directions by abutment means rigidly secured to the rudder, and which rudder is rotatable upon its axis, in known manner, between the lower and upper end faces of the main rudder, which end faces project beam-like for-' Preferably, the distance wardly beyond the rudder-shaft. between the center of the rudder shaft to the front edge of the guide member is one-third of the diameter of the screw. The abutments limit the displacement of the guide member on both sides to about 15 to 20.
In the arrangement of the rudder with two lateral fins, the initial direction of the flow of water to the profilenose of the one-plane-main rudder is not disturbed. The resistance of the drop-shaped lateral fins which adjust themselves to the most favorable direction of flow, which is caused substantially by friction, is of no importance.
The balance of the rudder and a minimum ruddermoment is brought about by immediate abutment of the guide member outwardly at the smallest rudder-angles.
This rudder permits of practically the quietest control with far-reaching elimination of the cross-force of the screw at an extremely small rudder moment. A vehicle equipped with this rudder shows also during a back-up movement a good maneuverability towards both sides.
All measurements and profile shapes vary according to the purpose of use, according to the shape and speed of the vehicles in question.
The guide members have for instance a round nose and run rearwardly sharply in a straight line. The lateral distance of the guide member is approximately equal with the profile height of the main rudder. The profile height of the guide members is about one-fifth to one-tenth of their length.
It is also possible to control the guide member forcibly.
With these and other objects in view which will become apparent in the following detailed description, the present invention will be clearly understood in connection with the accompanying drawings, in which:
Figure 1 is a side elevation of a rudder for boats, using a one-plane main rudder;
Fig. 2 is a section along the lines 2--2 of Fig. 1;
Fig. 3 shows schematically the flow conditions in the case when the control rudder is set for starboard of 45;
Fig. 4 shows schematically the flow conditions in the case, when the control rudder is set for port of Fig. 5 is a side elevation of the device with a boxrudder;
Fig. 6 is a section along the lines 6-6 of Fig. 5;
Fig. 7 shows schematically the flo'w conditions in the case, when the control rudder of Fig. 5 is set for starboard of 45 Fig. 8 shows schematically the flow conditions in the case, when the control-rudder of Fig. 5 is set for port of 90";
Fig. 9 is a side elevation of the control-rudder with two fins;
Fig. 10 is a section along the lines 10-10 of Fig. 9;
Fig. 11 shows schematically the flow conditions in the case, when the control-rudder of Fig. 9 is set for star board of 45 and Fig. 12 shows schematically the flow conditions in the case, when the control-rudder of Fig. 9 is set for per of 90.
Referring now to the drawings, the main-rudder 3 and box-rudder 9, respectively, which are swingably mounted by means of the rudder-shaft 2 at the stern of the ship behind the ship-screw 1, has a lower end face 4 as well as an upper end face 5, which faces 4 and 5 project forwardly beyond the rudder-shaft 2. The shaft or shafts 6 of the guide member 7 are swingably mounted therein, and the displacement of the guide member 7 is limited by abutment members 8 which are disposed on the end faces 4, 5 and by the inner walls of the box-rudders 9, respectively.
If the main-rudder comprises a box-like two-plane rudder 9, the front edge of which is preferably in one line, with the rotating axis of the rudder, the guide member 7 is arranged between the lower and upper end faces, which project forwardly beyond the rotating axis of the rudder 9 in such a manner, that it penetrates partly with its rear end into the box-like two-plane rudder, in order to achieve a good abutment and a good stabilization by two-sided water pillows. The rotating axis 6 of the guide member 7 may be disposed in accordance with the requirements up to about one-fifth of the length of the front edge.
The distance between the two inner walls of the boxlike two-plane rudder 9 depends upon the angle of displacement of the guide member. This angle amounts in accordance with the requirements for the rudder, to about 15 to 45 towards each side. The larger displacement angles of the guide member create, for instance, in hard rudder positions greater cross-forces, while smaller displacement-angles bring about more favorable ruddermoments with small rudder angles.
The distance between the rotating axis 2 of the rudder to the rear edge of the box-like, two-plane main rudder should amount to at least one-half of the diameter of the screw, but must be so big, that an overbalance is avoided.
The guide member may comprise two fins 7, (Fig. 10), each of Which may swing upon axles 6 disposed laterally and symmetrically to the longitudinal median plane of the rudder-blade 3, the distance between the axles 6 being smaller than the depth of the fins in the initial direction of the flow. The abutments are preferably arranged in such a manner, that the inner face of the fins 7 which are directed away from the initial direction of the flow in its final displacement forms an angle of about with the symmetrical plane of the rudder and that the fin directed towards the direction of flow forms a displacement at a rudder displacement of over 45 towards the first mentioned fin. In this case, which occurs only in hard rudder positions, the angle of the inward displaced guide members to the symmetrical plane is about 120 and 60, respectively.
The effect of the rudder designed in accordance with the present invention is based on the fact that the screw stream is brought on the low pressure side of the rudder up to a displacement of 90 into engagement and is shifted over between the two faces of the box-rudder, respectively, by means of a guide member, which is swingably disposed in front of the rotating axis within the rudder body, self-adjustable by the screw stream and limited in its movement by an abutment.
Since the size of the guide member stands in a predetermined relation to the diameter of the screw, the total screw stream is deflected, so that upon setting of the rudder at a displacement of 90 practically no driving force is present in the midship-line. By this arrangement an absolute turning on its place is made possible. Practically, not only a turning on its place is made possible with the rudder, but under favorable conditions also to lay the course without backward movement. The backward movement is, therefore, used 80% less than with a normal, conventional rudder.
For these reasons, the reverse drive and the directly reversible engine is appreciably saved. The cross-force of the screw is mostly balanced out by this rudder.
j The rudder moment is smaller and more evenly distributed over the entire range of displacement of the rudder than with any other rudder. Since the rudder operates effectively just at slow speed, the use of a maneuver with full force at suddenly occurring difficulties in narrowest space is widely eliminated.
It is to be emphasized that ships which are equipped with this rudder must not be designed for extremely large maneuverability, i.e., it is possible to create with ease ships having s'tabile course and best maneuverability. The present rudder is of advantage for the common safety of the ship-navigation.
While I have disclosed several embodiments of the present invention, it is to be understood that these embodiments are given by example only and not in a limiting sense, the scope of the present invention being determined by the objects and the claims.
I claim:
1. A steering rudder for ships having a guide member, including a driving screw, a first vertical axle for rotatable mounting of said rudder and at least one second vertical axle for rotatable mounting of said guide member, said second axle being disposed parallel to and, in the direction of movement of said ship, in front of said first axle, and abutment means connected with said rudder and limiting the angular displacement of said guide member towards both sides from a central normal position, and said rudder having beam-like upper and lower end faces projecting forwardly beyond said first vertical axle andsaid second vertical axle being rotatably mounted in said upper and lower end faces of said rudder.
2. The rudder, as set forth in claim 1, wherein the distance from the center of said first axle to the front edge of said guide member amounts to about one-third of the diameter of said driving screw.
3. The rudder, as set forth in claim 1, wherein said abutment means are arranged in such a manner that the displacement of said guide member is limited to an angular displacement range of 15 to 20.
4. The rudder, as set forth in claim 1, wherein said rudder is formed as a box-like two-plane rudder and the forward edge of the latter is disposed in one line with said first rotating axle of said rudder, and said guide member projects partly into said box-like rudder and the inner faces of the latter limit the angular displacement of said guide member to an angular range of about 15 to 45 towards each side from a normal, central position.
5. The rudder, as set forth in claim 1, wherein said guide member comprises two fins rotatable upon axles disposed laterally and symmetrically to the longitudinal median plane of said rudder, the distance between said axles being less than the depth of said fins taken in the initial direction of flow.
6. The rudder, as set forth in claim 5, wherein the inner faces of said fin disposed on the side opposite the initial direction of flow form an angle of about 15 with the symmetrical plane of said rudder at their greatest displacement and said fin disposed toward the initial direction of flow abuts said first mentioned fin at an angular displacement of about more than 45.
7. The steering rudder, as set forth in claim 1, iWherein said rudder is disposed in a median line coinciding with the axis of said driving screw, and said rudder forms an angle of about towards said median line in its hard position.
References Cited in the file of this patent UNITED STATES PATENTS Lee Aug. 21, 1928
US685898A 1956-09-28 1957-09-24 Rudder for boats Expired - Lifetime US2910954A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4771717A (en) * 1987-04-30 1988-09-20 Cruson Donald C Rudder for a water vessel
WO1990012733A1 (en) * 1989-04-26 1990-11-01 Unger William J Keel assembly
FR2746362A1 (en) * 1996-03-20 1997-09-26 Blohm Voss Ag FLOW GUIDING DEVICE
WO2021246885A1 (en) * 2020-06-04 2021-12-09 Mapalu Sp. Zo.O. Passive rudder blade for power-driven vessels

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3101693A (en) * 1959-07-27 1963-08-27 Schilling Karl Rudder control arrangement
JPS52115097A (en) * 1976-03-22 1977-09-27 Nippon Kokan Kk <Nkk> Comb type ladder

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US46807A (en) * 1865-03-14 Improved rudder
USRE16508E (en) * 1926-12-28 To auton
US1661114A (en) * 1917-06-16 1928-02-28 Flettner Anton Method and device for the steering of ships
US1681415A (en) * 1925-06-29 1928-08-21 Harold A Lee Wind-controlled steering gear

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US46807A (en) * 1865-03-14 Improved rudder
USRE16508E (en) * 1926-12-28 To auton
US1661114A (en) * 1917-06-16 1928-02-28 Flettner Anton Method and device for the steering of ships
US1681415A (en) * 1925-06-29 1928-08-21 Harold A Lee Wind-controlled steering gear

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4771717A (en) * 1987-04-30 1988-09-20 Cruson Donald C Rudder for a water vessel
WO1990012733A1 (en) * 1989-04-26 1990-11-01 Unger William J Keel assembly
FR2746362A1 (en) * 1996-03-20 1997-09-26 Blohm Voss Ag FLOW GUIDING DEVICE
WO2021246885A1 (en) * 2020-06-04 2021-12-09 Mapalu Sp. Zo.O. Passive rudder blade for power-driven vessels

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BE560995A (en)
FR1183776A (en) 1959-07-13
GB847400A (en) 1960-09-07

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