Patent Publication Number: US-9889918-B2

Title: Trimmable rudder

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 13/598,181, filed Aug. 29, 2012 and issued as U.S. Pat. No. 9,242,710 on Jan. 26, 2016, entitled  Trimmable Rudder . The subject matter of this application is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention generally relates to marine trimming systems and, more particularly, to a rudder configured for steering and trimming a marine vessel. 
     Discussion of the Related Art 
     Flaps and trim tabs are known for influencing primarily roll and pitch movements of marine vessels to control listing and assist planing of the vessels so that the vessels can be stabilized at a desired attitude. This is typically accomplished by one or more flaps or trim tabs coupled, attached, or otherwise carried by a larger component or structure of the vessel, such as on a lower portion of a transom wall of the vessel. As is generally understood, adjustments are typically carried out by adjusting an angle of the flaps or trim tabs relative to the larger component or structure. 
     Flaps and trim tabs of the kind generally known in the art have a single degree of freedom of movement with respect to the component to which they are mounted. Each of the flaps and trim tabs pivots about a single pivot axis that is typically arranged generally horizontally so that up and down pivoting of the flap or trim tab provides a pitch-type rotation that defines the single degree of freedom of movement. Pivoting a flap or trim tab down presents a relatively large surface area to the water and increases hydrodynamic appendage drag. This provides negative lift by way of reactionary forces to the hydrodynamic appendage drag that roll and/or pitch the vessel to oppose a non-desired oppositely directed roll and/or pitch that is being corrected to reduce listing or assist planing of the vessel. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a trimmable rudder system for vessels such as power boats that include a pair of rudder blades that are independently moveable in multiple directions to allow the rudder blades to be positioned with respect to each other so as to collectively achieve a desired hull trim change, including listing control and planing control of the power boat. Each of the rudder blades may have three rotational degrees of freedom so that each of the rudder blades can rotate about X, Y, and Z axes. This may be done with a ball-and-socket joint at each of the rudder blades that allows their independent position adjustability. This allows the rudder blades to be positioned with respect to each other so as to collectively achieve a desired hull trim change, including listing control and planing control of the power boat. The rudder blades can be positioned with respect to each other to collectively achieve a hull trim change while maintaining the rudder blades substantially aligned with the water flow direction past the rudder blades so as to achieve the hull trim change substantially without increased hydrodynamic appendage drag beyond levels provided by rudder based steering systems. This may allow for a low-drag, highly efficient, trimming system for a planing power boat. 
     In accordance with a first aspect of the invention, the trimmable rudder system may provide combined steering and trimming capabilities for a power boat. A steering system of the power boat controls direction of travel of the power boat and includes a steering actuator and a rudder assembly that includes a rudder blade that extends generally vertically into the water. A rudder shaft of the rudder assembly is connected to the steering actuator and has a longitudinal axis. The rudder shaft can rotate about the longitudinal axis to rotate the rudder blade for steering the power boat. A joint is arranged between a hull of the power boat and the rudder assembly so that the rudder shaft can pivot about an axis that extends in a transverse direction through the joint that is generally perpendicular to the longitudinal axis of the rudder shaft. This may allow for controlling a rudder assembly to allow compound movements of a rudder blade for providing positive or negative lift forces to the power boat to induce trimming and/or other hull orientation effects. 
     In accordance with another aspect of the invention, the joint may be a ball-and-socket joint. The rudder shaft and the rudder blade may extend from opposing sides of the ball-and-socket joint. The ball-and-socket joint may include a ball that has a ball passage extending therethrough and the rudder shaft may extend through and rotate inside of the ball passage. A collar may be connected to and extend from the ball so that the collar and ball move in unison with each other. The collar may have a collar passage that is aligned with the ball passage so that the rudder shaft extends through and can rotate inside of both of the ball and collar passages. This may allow for a compact configuration that can be housed substantially entirely inside of a hull while allowing for compound, multi-axis, positional control of a rudder blade. 
     In accordance with another aspect of the invention, the power boat has a hull that is configured to allow the power boat to travel through water at a planing speed, and the power boat includes a pair of rudder assemblies extending from the hull and connected to the steering system. Each of the rudder assemblies may include a rudder blade that extends generally vertically into the water and a rudder shaft that is connected to the steering system and has a longitudinal axis about which the rudder shaft can rotate to correspondingly rotate the rudder blade for steering the power boat. A joint, which may be a ball-and-socket joint, is arranged between a hull of the power boat and the rudder so that each respective rudder shaft and rudder blade can pivot toward and away from each of the bow, the stern, the port side, and the starboard side, of the hull. This allows for coordinated movements of the rudder blades to provide substantial amounts of control of hull trim changes while minimizing appendage drag. 
     In accordance with another aspect of the invention, a drive having at least one propeller is aligned with a centerline of the hull and the pair of rudder assemblies is arranged on opposing sides of the centerline of the hull. This may be a single engine implementation of the power boat. In a two-engine implementation of the power boat, a pair of drives, each of which includes at least one propeller, is arranged on opposing sides of a centerline of the hull. The pair of rudder assemblies may be aligned with the pair of drives so that each rudder assembly is positioned within a jet-stream of the respective drive. 
     In accordance with another aspect of the invention, each of the rudder assemblies includes a trim actuator that can pivot the respective rudder blade in a longitudinal direction with respect to the hull and a camber actuator that can pivot the respective rudder blade in a transverse direction with respect to the hull. The steering system can operate the trim and camber actuators of the rudder assemblies independent of each other. Movement of the trim and camber actuators can be coordinated to provide an infinitely variable adjustment of position of each of the rudder blades. The trim, camber, and steering actuators can include hydraulic rams, other linear actuators such as electric motor driven ball and screw actuators or, optionally, non-linear actuators. This may provide a system for both steering and trim control that requires relatively few components. 
     In accordance with another aspect of the invention, a steering arm that is moved by the steering actuator is connected to and rotates in unison with the rudder shaft. A plate that supports the steering arm and the steering actuator may be arranged toward an upper end of each of the rudder assemblies. The plate may be spaced from the hull and move in unison with upper end of the rudder assembly. This may allow the steering actuator to maintain an alignment with the rudder shaft even while the rudder shaft and rudder blades move in trim and camber directions which allows the steering actuator to be able to rotate the rudder shaft regardless of the position of the rudder shaft and rudder blade with respect to the bow, the stern, the port side, and the starboard side, of the hull. 
     In accordance with another aspect of the invention, a pair of steering actuators may be supported on the plate and engages opposing ends of the steering arm. The steering actuators may be arranged on opposing sides of the rudder shaft which allows the steering actuators to advance or regress in opposite directions to rotate the rudder shaft, which may allow for relatively small actuators to be implemented for rotating the rudder shaft and thus a relatively compact unit for tiller-type steering function at each of the rudder assemblies. 
     According to another aspect of the preferred embodiments, methods of steering and trimming a planing vessel via the claimed apparatus are also provided. 
     Various other features, embodiments, and alternatives of the present invention will be made apparent from the following detailed description taken together with the drawings. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration and not limitation. Many changes and modifications could be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings, in which like reference numerals represent like parts throughout, and in which: 
         FIG. 1  is a simplified schematic representation of a trimmable rudder system according to the invention; 
         FIG. 2  is a partial cross-sectional view of the marine vessel illustrating a trimmable rudder assembly of  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of the trimmable rudder assembly as shown in  FIG. 2 ; 
         FIG. 4  is an isometric view of a variant of the trimmable rudder assembly of  FIG. 2  showing movement of a rudder thereof in phantom; 
         FIG. 5  is a side elevation view of the trimmable rudder assembly of  FIG. 1  showing the rudder in a neutral position; 
         FIG. 6  is a rear elevation of a simplified schematic representation of a pair of trimmable rudder assemblies according to another embodiment of the invention showing a control unit in a neutral position; 
         FIG. 7  is a side elevation view of the trimmable rudder assemblies of  FIG. 6  showing the rudder blade(s) in a forward-rake position; 
         FIG. 8  is a rear elevation of the trimmable rudder assemblies of  FIG. 6  showing the rudder blades in a camber-out position; 
         FIG. 9  is a side elevation view of the trimmable rudder assembly of  FIG. 6  showing the rudder blade(s) in a rear-rake position; and 
         FIG. 10  is a rear elevation view of the trimmable rudder assembly of  FIG. 6  showing the rudder blades in a camber-in position. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIG. 1 , a trimmable rudder system  2  is shown as provided in a marine vessel, e.g., a power boat  10  that includes a hull  12  which defines a bow at the front of the hull  12 , a stern at the back of the hull  12 , and port and starboard sides at the left and right sides of the hull  12 . Hull  12  and thus power boat  12  are configured for traveling through water at a planing speed. The power boat  10  includes at least one drive  14  that receives power from an engine (not shown) and that includes at least one propeller  15 , as is generally understood. A steering system  16  is provided for controlling the direction of travel as well as trimming of the vessel, as will be discussed. The steering system  16  includes a steering wheel  17 A, a trim control button(s)  17 B, or other user control interface that is operably connected to at least one rudder assembly  18 , preferably a pair of rudder assemblies  18 , for controlling the rudder assembly or assemblies  18 . A control system  19  may be operably connected to the steering system  16  and each of the rudder assemblies  18 . The control system  19  may include a controller  19 A and power supply  19 B, as is known, for controlling various components of the rudder assemblies  18 , explained in greater detail elsewhere herein, and based on user inputs from the steering system  16 . The controller  19 A can include an industrial computer or, e.g., a programmable logic controller (PLC), along with corresponding software and suitable memory for storing such software and hardware including interconnecting conductors for power and signal transmission for controlling electronic or electro-mechanical components of the rudder assemblies  18  and can also include valve assemblies for controlling hydraulic components of the rudder assemblies  18 . 
     Referring now to  FIGS. 2 and 3 , each rudder assembly  18  may be housed within an engine room or otherwise below a deck of the power boat  10 , with the rudder blade  20  extending below a bottom wall of the hull  12  into the water. Each rudder assembly  18  includes a rudder blade  20  that is connected to a rudder shaft  22  defining a longitudinal axis about which the rudder blade  20  and shaft  22  may be rotated as controlled by the steering system  16  for steering the power boat  10 . The rudder shaft  22  is coupled to a joint that is shown as a ball-and-socket joint  24  that is disposed between the rudder blade  20  and the steering system  16 . The ball-and-socket joint  24  allows movement of the rudder blade  20  in a number of additional planes and about multiple axes to provide compound, multi-axis, positional control of each rudder blade  22 , in addition to the rotation about the longitudinal axis of the rudder shaft  22  for steering. Coordinating the movements of the rudder blades  20  by way of the steering and control systems  16 ,  19  allows the trimmable rudder system  2  ( FIG. 1 ) to achieve desired hull trim changes, including listing control and planing control of the power boat  10 . 
     Referring now to  FIG. 4 , at each rudder assembly  18 , the steering system  16  ( FIG. 1 ) is operably coupled to a pair of actuators, shown as camber actuator  26  and trim actuator  28  that connect to an upper end of rudder assembly to control trim and camber movements, respectively, of the rudder blade  22 . Camber and trim actuators  26 ,  28  are shown as hydraulic ram-style linear actuators, although it is understood that other linear actuators such as pneumatic rams, hydraulic-pneumatic rams, and electric motor driven ball and screw actuators, optionally non-linear actuators, may be used. The camber actuator  26  and the trim actuator  28  are similarly constructed such that reference to one is equally applicable to the other. The camber and trim actuators  26  and  28  have a first end  30  coupled to the hull  12  of the power boat  10  and a second end  32  opposite the first end  30  and coupled to the rudder assembly  18 . The camber and trim actuators  26  and  28  each has a cylinder  34  that securely receives a movable rod  36 , which may include a piston coupled to an end thereof. The rod  36  is movable relative to the cylinder  34  upon introduction of a fluid such as a liquid-like oil. In particular, the camber and trim actuators  26  and  28  are operably coupled to a hydraulic fluid source that is operably controlled by way of the steering system  16  of the power boat  10  as is known in the art. 
     Still referring to  FIG. 4 , the trimmable rudder system  2  ( FIG. 1 ) further includes at least one steering actuator, shown as a pair of steering actuators  38  and  40 , operably coupled to the rudder blade  20  for rotation about a vertical axis thereof. Like the camber and trim actuators  26  and  28 , the steering actuators  38  and  40  are linear actuators that include a cylinder  42  and which include a rod  44 , respectively, movable with respect thereto. The rods  44  may each include a piston at ends thereof as is generally understood in the art. The cylinders  42  may be in communication with a fluid source in the same manner as the camber and trim actuators  26  and  28  as may be generally understood. The actuators  38  and  40  may be supported on a plate  46  or similar structure and include first and second ends  48  and  50  opposite one another and coupled to opposite ends of the plate  46 . In particular, the first end  48  is coupled to the plate  46  at a post  52  that is rigidly connected to the plate  46 . At the opposite end, the second end  50  of the actuators  38  and  40  are coupled to a movable steering arm  54  that is coupled to the shaft  22  and configured to transmit rotation thereto, as will be described. The rods  44  are movably coupled to corresponding pins  56  coupled to the steering arm  54 . The actuators  38  and  40  are configured to operate in opposition to one another and are in fluidic communication with a fluid source such as oil, water, or the like. In this manner, to extend the rod  44  of one of the actuators  38  and  40 , the corresponding cylinder  42  is filled with fluid so that the rod  44  moves relative thereto. The movement of the rod  44  urges the steering arm to rotate about a vertical axis to thereby rotate the shaft  22 , as will be described further herein. 
     Referring again to  FIGS. 2 and 3 , the plate  46  of the rudder assembly  18  is spaced from the hull  12  and moves in unison with an upper end of the rudder assembly  18  while supporting the steering actuators  38 ,  40 . This maintains the steering actuators  38 ,  40  in a position with respect to the steering arm  54  and rudder shaft  22  so that the steering actuators  38 ,  40  can always push or pull the steering arm  54  and turn the rudder shaft  22 , regardless of the position of the rudder shaft  22  with respect to the hull  12 . Plate  46  is oriented orthogonally to the rudder shaft  22  and configured to accommodate rotation of the shaft  22  about its vertical axis by way of the steering arm  54  for rotating the rudder blade  20 . The shaft  22  extends through a hole  47  ( FIG. 3 ) in the plate  46  and is coupled for rotation in unison with the steering arm  54 . The shaft  22  extends downwardly from the plate  46  and through the ball-and-socket joint  24 , which correspondingly includes a ball  58 . A hole, aperture, or other such passage, shown as ball passage  58 A ( FIG. 3 ), extends through the ball  58 . 
     Referring again to  FIG. 4 , the ball-and-socket joint  24  differs from that shown in  FIGS. 2 and 3  in that the ball-and-socket joint  24  of  FIG. 4  includes a collar  59  that extends upwardly from the ball  58  concentrically around the rudder shaft  22 . A collar passage  59 A extends longitudinally through the collar  59  and aligns with the ball passage  58 A. In this way, the rudder shaft  22  extends through both the ball and collar passages  58 A,  59 A. 
     Still referring to  FIG. 4 , the ball  58  is received in a socket  60 . The socket  60  holds the ball  58  in a manner that allows the ball  58  to freely rotate in the socket  60 , as will be discussed in additional detail herein. The socket  60  may include a recess or similar spherical void toward an upper end of the socket  60  for receiving the ball  58  while permitting rotating articulation of the ball  58 . At a lower end of the socket  60 , a hole, aperture, or passage is provided through which the shaft  22  may extend beneath the hull  12  of the power boat  10  and direct movement of the rudder blade  20 , which is affixed to a distal end of the shaft  22 . The socket  60  may include a generally flat bottom flange  62  which is coupled to and sealed against an underside of the hull  12  of the power boat  10 . 
     Still referring to  FIG. 4 , the rudder assembly  18  is shown in further detail and its operation will now be further explained. As previously described, the camber and trim actuators  26  and  28  and  38  and  40  are operably coupled to a fluid source as is generally understood. Understandably, alternative actuator assemblies are within the scope of the present invention and may be utilized in driving movement of the rudder assembly  18 . 
     The camber actuator  26 , as previously discussed, is coupled at it second end to the rudder assembly  18 . More particularly, the camber actuator  26  is coupled to a mounting block  64  disposed beneath the plate  46  and coupled to the shaft  22  in a manner so as to generate camber to the rudder blade  20 , as will be explained. The second end of the camber actuator  26  includes a pin  66  that is coupled to the mounting block  64  and which is movable to drive movement of the rudder assembly  18 . The pin  66  connects to a yoke  68  to couple the mounting block  64  and the camber actuator  26  to each other. Thus, as desired, the operator of the power boat  10  may adjust the camber angle of the rudder blade  20 , and thus the transverse angle of the rudder blade  20  with respect to the hull  12 , by applying the appropriate actuation through the camber actuator  26  as controlled by inputting a command through the steering system  16 , for example, by manipulating the trim control button(s)  17 B. In this manner, the rod  36  may be moved relative to the cylinder  34  to apply a force to the rudder assembly  18  via the shaft  22  ( FIGS. 2 and 3 ) and/or collar  59  ( FIG. 4 ) to thereby adjust the camber of the rudder blade  20 . In particular, to adjust the camber of the rudder blade  20  toward the port side of the vessel, the rod  36  may be retracted into the cylinder  34  such that the upper end of the rudder assembly  18  is pulled toward the starboard side of the power boat  10  while the bottom edge of the rudder blade  20  tilts toward the port side. To adjust the camber of the rudder blade  20  toward the starboard side, the rod  36  is extended from the cylinder  34  in an inverse manner as may be appreciated. 
     In a similar manner, the trim actuator  28  may be directed to adjust the trim angle of the rudder blade  20 . The rudder blade  20  may be pivoted toward the bow of the power boat  10  by extending the rod  36  from the cylinder  34  and may be pivoted toward the stern of the power boat  10  by retracting the rod  36  into the cylinder  34 . In this manner, the camber actuator  26  and trim actuator  28  may simultaneously direct movement of the rudder blade  20  to provide compound movements that adjust both camber and trim angles of the rudder blade  20 . To control rotation of the rudder blade  20  about its vertical axis or the shaft  22 , the operator of the power boat  10  may turn the steering wheel  17 A to actuate the opposing actuators  38  and  40 . In particular, to rotate the rudder blade  20  in a first, clockwise direction when viewed from below, the rod  44  of the actuator  40  is moved rearwardly while the rod  44  of the actuator  38  is moved forwardly. The movement of the rods  44  in this manner rotates the steering arm  54  about a vertical axis. The steering arm  54  is coupled to the rudder shaft  22  and thereby rotates the rudder blade  20  in unison with the steering arm  54 . This is shown in  FIG. 4  at the rudder assembly  18  on the left-hand side in which the rudder blade  20  moves from its position shown in phantom outline to its position in solid outline. To rotate the rudder blade  20  in the second, counterclockwise direction when viewed from below, the rods  44  of the actuators  38  and  40  are moved rearwardly and forwardly, respectively. In this manner, the movement of the actuators  38  and  40  is applied to the steering arm  54  to which the shaft  22  is coupled, which transmits to rotation of the rudder blade  20 . This is shown in  FIG. 4  at the rudder assembly  18  on the right-hand side in which the rudder blade  20  moves from its position shown in phantom outline to its position in solid outline. 
     With additional reference now to  FIGS. 5-10 , preferably the trimmable rudder system  2  includes a pair of rudder assemblies  18 . Referring to  FIG. 6 , the drive  14  in the middle shows a position of a dive  14  for a single drive and single engine application. In such a single drive application, the rudder assemblies  18  are arranged transversely outward of the drive  14 . The two drives  14  at the outside of  FIG. 6  show a position of a pair of drives  14  for a two drive, which may be a two engine, application. In such two drive applications, the rudder assemblies  18  are aligned with and aft of the drives  14 . This arranges the rudder assemblies  18  within jet-streams of propellers of the drives  14 . 
     As can be seen in  FIGS. 5-10 , the rudder blades  20  may be adjusted to carry out a number of positional changes and coordinated movements simultaneously to provide steering and/or non-steering hull movements, including desired hull trim changes for listing control and planing control of the power boat  10 . With momentary reference to  FIG. 5 , one of the rudder blades  20  of the present embodiment is shown in a generally neutral position. Understandably, the other of the rudder blades  20  is not visible so it is likewise positioned in the neutral position as shown. Now with reference to  FIG. 6 , the rudder blades  20  are shown in a camber neutral position in keeping with the present invention. 
     With reference now to  FIG. 7 , one of the rudder blades  20  is shown in a forward-rake position in which a bottom edge of the rudder blade  20  is tilted forward relative to the neutral position. In this manner, a negative lift may be applied to the bow of the hull  12  so as to urge the bow downward. Now referring to  FIG. 8 , the rudder blades  20  are shown in a camber-out configuration in which both of the rudder blades  20  are angled outwardly relative to their neutral positions. Shown in phantom outline in  FIG. 8 , leading edges of the rudder blades  20  can be angled toward each other to provide a toe-in configuration. With the rudder blades  20  positioned in a camber-out and toe-in arrangement, positive lift can be achieved to urge the bow of the hull  12  upward. 
     Referring now to  FIGS. 9 and 10 , the rudder blades  20  are shown in generally opposite positions as those shown in  FIGS. 7 and 8 , respectively. As shown in  FIG. 9 , the rudder blades  20  are in a rear-rake position in which the bottom edge of the rudder blade  20  is tilted rearward relative to the neutral position. In this manner, a positive lift may be applied to bow of the hull  12  so as to urge the bow upward. Now referring to  FIG. 10 , the rudder blades  20  are shown in a camber-in configuration in which both of the rudder blades  20  are angled inward relative to their neutral positions. Shown in phantom outline in  FIG. 10 , leading edges of the rudder blades  20  can be angled away from each other to provide a toe-out configuration. With the rudder blades  20  positioned in a camber-in and toe-out arrangement, negative lift can be achieved to urge the bow of the hull  12  downward. 
     Although the best mode contemplated by the inventors of carrying out the present invention is disclosed above, practice of the present invention is not limited thereto. It will be manifest that various additions, modifications, and rearrangements of the aspects and features of the present invention may be made in addition to those described above without deviating from the spirit and scope of the underlying inventive concept. The scope of some of these changes is discussed above. The scope of other changes to the described embodiments that fall within the present invention but that are not specifically discussed above will become apparent from the appended claims and other attachments.