Abstract:
A remote tiller control system includes a drive unit mounted to the tiller. The drive unit is adapted to move the tiller back and forth when selectively powered. A handheld remote control transmitter unit is provided to remotely control the drive unit and thus the position of the tiller. The drive unit includes a motor-drive gear that engages a curved rack. The motor is fixed to the tiller while the rack is fixed to a control arm. The end of the control arm is tied off to the boat to create the leverage needed to counteract the steering force on the tiller. Rotation of the gear against the rack creates a moment which drives the tiller.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority from U.S. provisional patent application Ser. No. 60/581,570 filed Jun. 21, 2004; the disclosures of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Technical Field  
         [0003]     The present invention generally relates to remote controlled steering units for boats and, more particularly, a remote control steering unit that works with a tiller such as a tiller on a small sailboat. Specifically, the present invention relates to a remote control tiller driver that is mounted to the tiller itself and fixed to the hull with unobtrusive stays to provide the leverage for turning the boat.  
         [0004]     2. Background Information  
         [0005]     Various types of small boats use a tiller to steer the boat. Tillers are the elongated arms connected the rudder of a sailboat. The tiller extends into the cockpit to allow the captain to vary the position of the rudder while the boat is underway. A tiller on a motorboat may be the handle that extends forwardly into the cockpit from the motor mounted to the stern of the boat. The motor has a leg that extends into the water. The leg supports a propeller and may support a rudder. In both situations, the captain of the boat uses the tiller to control the direction of the boat by moving the tiller back and forth in an arc with respect to the hull of the boat. The tiller is pivotably mounted to the hull such that the rudder turns the opposite direction of the tiller.  
         [0006]     There are numerous times on a boat when the captain needs to release the tiller and move about the boat. Such situations include the need to tighten sheets, drop anchors, go below, or fend off a pier or another boat. Although an experienced captain may temporarily tie off a tiller and perform these tasks, the nature of a moving boat on water—especially in sailboat—requires almost constant adjustment of the tiller position to maintain a steady course. The captain thus desires a device that allows the steering system to be controlled remotely so that the captain may adjust the course from any position on the boat. The device should be designed so that it may be retrofit to existing steering systems without the need for extensive modifications to the system or the hull of the boat. The system should also be portable so that the system does not encumber the captain as he moves about the boat. The system should also be easy to use so that the steering system may be controlled while the captain is performing other tasks. The system should also be relatively weather-proof so that is not damaged when exposed to bad weather.  
       BRIEF SUMMARY OF THE INVENTION  
       [0007]     The invention provides a steering control system that allows the captain of a boat to remotely control the boat&#39;s steering system.  
         [0008]     In one configuration, the invention provides a remote tiller control system having a drive unit mounted to the tiller. The drive unit is adapted to move the tiller back and forth when selectively powered. A handheld remote control transmitter unit is provided to remotely control the drive unit and thus the position of the tiller. A control arm extends from the drive unit and is tied off to a portion of the boat to provide the leverage needed to counteract the steering force on the tiller.  
         [0009]     In another configuration, the transmitter unit transmits a radio frequency signal to a receiver. The receiver is connected to a controller that controls a motor which drives a gear. The motor is fixed with respect to the tiller. The gear meshingly engages a rack that is fixed with respect to a control arm. The rack pivots with respect to the motor. Rotation of the gear creates a moment which drives the tiller in one direction. Rotating the gear in the opposite direction creates a moment in the opposite direction to move the tiller in the opposite direction. The captain may thus control the direction of the tiller from a location remote from the tiller.  
         [0010]     In another configuration, pulleys are supported by the tiller with stays wrapped around the pulleys. A motor is used to drive the pulleys and thus pull the tiller in one direction or the other. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0011]      FIG. 1  is a schematic view of one configuration of the remote tiller controller of the present invention.  
         [0012]      FIG. 2  is a top plan view of the cockpit and stern of a sailboat with the first configuration of the remote tiller controller installed on the tiller.  
         [0013]      FIG. 3  is an enlarged view of the motor, gear, rack, and control arm of the remote tiller controller.  
         [0014]      FIG. 4  is a view similar to  FIG. 2  showing the tiller in a different position than  FIG. 2 .  
         [0015]      FIG. 5  is a top plan view of a second configuration of the remote tiller controller of the invention.  
         [0016]      FIG. 6  is a side view of the alternative steering control unit of  FIG. 5 .  
         [0017]      FIG. 7  is a top plan view of a third configuration of the remote tiller controller of the invention installed on a tiller.  
         [0018]      FIG. 8  is a side view of the third configuration.  
         [0019]      FIG. 8A  is an enlarged section view of the connector used to secure the control arm to the rack.  
         [0020]      FIG. 9  is a view similar to  FIG. 7  with the housing of the drive unit removed. 
     
    
       [0021]     Similar numbers refer to similar parts throughout the specification.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0022]     The first and third configurations of the remote tiller controller of the present invention are indicated generally by the numeral  10 . Controller  10  generally includes a remote control transmitter unit  12  and a drive unit  22  adapted to receive a signal from transmitter unit  12  and control the direction of a tiller  30  with respect to the hull of a boat  32 . In the first configuration shown in  FIG. 1 , controller  10  also includes a receiver  14 , a power source  16 , a servo  18 , and a motor switch  20 . Controller  10  may be used to control the position of tiller  30  from any location where unit  12  can successfully transmit a signal to receiver  14 . Controller  10  may thus be used by a captain who needs to move about boat  32  to locations where he cannot directly grasp tiller  30 . Controller  10  also may be used by a captain who is knocked overboard in order to steer the boat into the wind in order to give him time to rejoin the boat.  
         [0023]     In general, the user of controller  10  may control the position of the tiller  30  on a boat  32  by manipulating a switch  34  on remote control transmitter  12 . In one configuration, transmitter  12  may be worn on the wrist of the user. Switch  34  may have a neutral position, a left position, and a right position. When the user moves switch  34  to one of the left and right positions, transmitter  12  creates a signal that is received by receiver  14 . Receiver  14  creates a command signal that directs drive unit  22  to move the steering system of the boat in the direction that corresponds to the signal created by unit  12 . In the exemplary embodiment, the command signal is created by communicating the signal to servo  18  which moves in the direction commanded by the position of switch  34 . Servo  18  is connected to motor switch  20  such that movement of servo  18  causes motor switch  20  to move from a neutral position to one of two powered positions. The two powered positions provide current to drive unit  22  in two different directions causing drive unit  22  to move in one direction or the other. Motor switch  20  may also be a self-centering switch such that it automatically returns to the neutral position when the user returns switch  34  to its neutral position. Switch  34  may also be a self-centering switch that automatically returns to its neutral position. Other methods of creating the command signal may also be used with the invention. For instance, in the third configuration of the invention, receiver  14  is connected to a controller  15  that directly controls drive unit  22 . Transmitter  12  may also be hard wired to drive unit  22  for use by the captain in selected locations. Multiple transmitters  12  also may be used where one is hard wired at a selected location and another is wireless. For example, transmitter  12  and receiver  14  may incorporate spread spectrum, frequency hopping technology to activate relays that control the motor.  
         [0024]     Remote control  12 , receiver  14 , power source  16 , and servo  18  may be the typical components used with a remote controlled hobby vehicle such as a remote control car, boat, or airplane. Transmitter  12  may be powered by its own batteries  16 . Drive unit  22  may be powered by separate batteries  16  or a power source (such as a generator or a battery)  16  on boat  32 .  
         [0025]     Drive unit  22  generally includes a motor  40 , a pinion gear  42 , a rack  44 , and a control arm  46 . The position of control arm  46  is fixed with respect to rack  44 . Control arm  46  may be integrally formed with rack  44 . In the third configuration of the invention shown in  FIGS. 7-9 , control arm  46  is disposed outside a housing  47  while rack  44  is disposed inside housing  47 . The fixed connection between arm  46  and rack  44  is achieved with a connector  49  that includes an inner connector arm  51  and a shaft  53 . Arm  51  is fixed to rack and is non-pivotably connected to shaft  53 . Shaft  53  passes through housing  47  (and may pass through a seal or bushing to keep housing  47  weatherproof and is non-pivotably connected to arm  46 . The seal or bushing may be used to space arm  46  from the top of housing  47 . Shaft  53  may be welded to arms  46  and  51 . Shaft  53  may also be formed with non-circular portions  57  that engage corresponding non-circular openings in arms  46  and  51 . The different sections of shaft  53  may be stepped so seat the portions of shaft  53  in the correct position. The end of shaft  53  inside housing is designed to receive a fastener that keeps all of the elements together in a reliable configuration. The fastener may thread directly into the end of shaft  53 , may be a pin that passes through the end of shaft  53 , may be a snap ring, or may be any of a variety of other fasteners used for this purpose. This configuration essentially clamps arms  46  and  51  to the top of housing  47  such that rack  44  is pivotably supported by housing  47 .  
         [0026]     Rack  44  includes a plurality of gear teeth  48  disposed along an arc that limits the adjustment of tiller  30  by drive unit  22 . Rack  44  is concave with respect to gear  42 . Rack  44  may extend through an arc of 120 to 150 degrees and include approximately 25 to 40 teeth. Pinion gear  42  is driven by motor  40  and meshingly engages teeth  48 . Optionally, a transmission  50  may be used between pinion gear  42  and motor  40  to provide power to the system.  
         [0027]     In the first and third configurations, motor  40  is fixed with respect to tiller  30 . Motor  40  may be directly clamped to tiller  30  allowing drive unit  22  to be retrofit onto existing tillers  30 . As shown in  FIG. 2 , motor  40  may be mounted on the cockpit side of the rudder where tiller  30  typically extends. In another embodiment, tiller  30  may extend behind rudder (with respect to the boat) or a tiller extension may be used to support motor  40  (or unit  22 ) behind the rudder so that use of the boat&#39;s cockpit is not encumbered. In the third configuration, motor  40  is fixed to housing  47  and housing  47  is clamped or fastened to tiller  30  using a leg or clamp member  55 . The outer end of control arm  46  is, however, connected to the hull of boat  32 . Stays  60  may be used to hold arm  46  in position. In other embodiments, the forward end of arm  46  may be held in place with a single rigid arm that extends between the boat hull and the arm  46 . Rotation of pinion gear  42  by motor  40  creates a moment that moves drive unit  22  and thus moves tiller  30  in the manner depicted in  FIG. 4 . Tiller  30  pivots about its connection to boat  32  and drive unit  22  moves about the end of arm  46 .  
         [0028]     In the third configuration, a lock slide  80  is adjustably connected to arm  46  to allow the user to adjust the tie-off position of stays  60  and adjust the length of the lever arm. In this configuration, arm  46  defines an elongated channel  81  along which lock slide  80  and its lock clamp  82  may slide to different positions. Lock clamp  82  and lock slide  80  sandwich a portion of arm  46 . A nut  83  threadedly engages a threaded shaft  84  to tighten lock slide  80  in place. At least one shaft  85  or a pair of unthreaded shafts  85  are used to prevent lock slide  80  from pivoting. A threaded knob  85  is used to receive an eye or pulley  86  that receives stays  60 . Notches  87  are provided to pinch the ends of stays  60 . Lock slide  80  may be reversed on arm  46  to provide a position wherein knob  85  is disposed over the top of housing  47 .  
         [0029]     In another embodiment of the invention, one or more remote control transmitters may be built into different locations of the boat to allow the captain to control the steering system from different locations.  
         [0030]     The second alternative configuration of the system is depicted in  FIGS. 5 and 6  wherein a pair of pulleys  70  are driven by a motor  40 . Pulleys  70  are connected to tiller  30 . Stays  60  are wrapped around pulleys  70  in opposite directions such that the rotation of pulleys  70  pulls tiller in one direction or the other. Pulleys  70  may be driven with a chain  72  and a sprocket  74  drive as shown. Pulleys  70  may be driven by other transmissions.  
         [0031]     In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. The elements of the system may be fabricated from weather proof materials such as stainless steel and aluminum. Appropriate plastics or composites may also be used. Any dimensions provided are for exemplary purposes. Moreover, the description and illustration of the invention is an example and the invention is not limited to the exact details shown or described.