Lower unit steering control system

Abstract

This application describes a submersible steering control system, e.g., a submersible steering control system used to steer a trolling motor for a boat. Such a submersible steering control system can reduce the moment about a pivot mount coupled to the boat when the trolling motor includes a shaft of increased length and a submersible thruster using increased force (e.g., for use with larger vessels). The submersible steering control system described in this application can be used to include a shaft that is substantially solid (e.g., devoid of cables for power and/or control), thus increasing the strength of the shaft and further increasing the lifespan of the trolling motor. In some cases, the submersible steering control system is integrated with the submersible thruster, further reducing the moment between the steering control system and submersible thruster.

1 . A trolling motor comprising:
 a mount adapted to removably coupled to a marine vessel;   a shaft having a proximal end coupled to the mount and a submersible distal end;   a submersible steering control system coupled to the shaft distal end; and   a submersible thruster coupled to the steering control system;   wherein the submersible steering control system and the submersible thruster are configured to rotate about a longitudinal axis of the shaft.   
     
     
         2 . The trolling motor of  claim 1 , wherein the mount is adapted to be removably coupled to a deck of the marine vessel. 
     
     
         3 . The trolling motor of  claim 1 , wherein the marine vessel comprises a recreational fishing boat. 
     
     
         4 . The trolling motor of  claim 1 , wherein the shaft comprises a length in a range from three feet to ten feet. 
     
     
         5 . The trolling motor of  claim 1 , wherein the shaft comprises a hollow portion therein. 
     
     
         6 . The trolling motor of  claim 5 , wherein one or more components are passed through the hollow portion and coupled to one or both of the steering control system and the submersible thruster. 
     
     
         7 . The trolling motor of  claim 1 , wherein the shaft comprises a solid cross section. 
     
     
         8 . The trolling motor of  claim 1 , wherein the shaft comprises:
 a plurality of vertebrae stacked to form a column; and   at least one inelastic tension element threaded longitudinally through the plurality of vertebrae to link the vertebrae, wherein at least a portion of the shaft has a flexible configuration when the at least one tension element is released and a stiffened linear configuration when the tension element is tensed to react torque and bending moments on the shaft.   
     
     
         9 . The trolling motor of  claim 1 , wherein the submersible steering control system comprises a brushed DC motor. 
     
     
         10 . The trolling motor of  claim 1 , wherein the submersible steering control system is rotatably coupled to the submersible thruster with a steering shaft. 
     
     
         11 . The trolling motor of  claim 1 , wherein the submersible thruster comprises a horsepower in a range from about 0.3 hp to about 5 hp. 
     
     
         12 . The trolling motor of  claim 1 , wherein one or more of the mount, the shaft, the steering control system, and the submersible thruster are removably coupled to each other. 
     
     
         13 . A method of manufacturing a trolling motor, the method comprising the steps of:
 coupling a mount to a proximal end of a shaft, wherein the mount is adapted to be removably coupled to a marine vessel; and   rotatably coupling a submersible steering control system and a submersible thruster to the shaft, wherein the submersible steering control system is adapted to control the submersible thruster.   
     
     
         14 . The method of  claim 13 , wherein the submersible steering control system is coupled proximate to the submersible thruster. 
     
     
         15 . The method of  claim 13 , wherein the marine vessel comprises a recreational fishing boat. 
     
     
         16 . The method of  claim 13 , wherein the shaft comprises a length in a range from three feet to ten feet. 
     
     
         17 . The method of  claim 13 , wherein the shaft comprises a solid cross section or a hollow portion therein. 
     
     
         18 . The method of  claim 10 , wherein the shaft comprises:
 a plurality of vertebrae stacked to form a column; and   at least one inelastic tension element threaded longitudinally through the plurality of vertebrae to link the vertebrae, wherein at least a portion of the shaft has a flexible configuration when the at least one tension element is released and a stiffened linear configuration when the tension element is tensed to react torque and bending moments on the shaft.   
     
     
         19 . The method of  claim 13 , wherein the submersible steering control system comprises a brushed DC motor. 
     
     
         20 . The method of  claim 13 , further comprising coupling the submersible steering control system to the submersible thruster with a steering shaft, such that the steering shaft is configured to rotate with the submersible steering control system and the submersible thruster. 
     
     
         21 . The method of  claim 13 , wherein the submersible thruster comprises a horsepower in a range from about 0.3 hp to about 5 hp. 
     
     
         22 . The method of any one of  claims 13 to 21 , wherein the steering thruster control system is configured to rotate with the submersible thruster in unison about the longitudinal axis of the shaft. 
     
     
         23 . The method of any one of  claims 13 to 22 , wherein the steering thruster control system is configured to be located from about 1 ft above a water surface line, to about 5 ft below the water surface line.