Marine drive system and method

A marine drive system comprising:

• (a) a longitudinally extending drive shaft assembly pivotally attached to a vessel;
• (b) a hydraulic cylinder pivotally attached to said vessel;
• (c) a translatable piston positioned within said hydraulic cylinder, said piston separating said hydraulic cylinder into a first cylinder area and a second cylinder area, said piston having a piston rod with a first end attached to said piston and a second end extending outward from said cylinder and pivotally attached to said drive shaft assembly;
• (d) a coiled spring positioned within said first cylinder area of said hydraulic cylinder providing a spring force translating said piston toward said second cylinder area extending said piston rod from said cylinder;
• (e) fluid filling said cylinder including said first and said second cylinder areas;
• (f) a cylinder flow line from said first cylinder area of said hydraulic cylinder whereby said fluid in said first cylinder area may be evacuated;
• (g) a fluid reserve tank in fluid communication with said cylinder flow line;
• and
• (h) a valve controlling flow from said cylinder flow line to said fluid reserve tank whereby fluid evacuated from said first cylinder area may be directed.

A method for propelling a vessel in shallow or obstacle strewn waterways comprising the steps of:

• (a) providing a vessel having an engine for transmitting engine torque and rotation;
• (b) providing a drive shaft assembly having a housing enclosing a drive shaft having an attached propeller and a skeg;
• (c) attaching said drive shaft assembly to said vessel to allow said drive shaft to pivotally move vertically and horizontally;
• (d) attaching said drive shaft to said engine to allow transmission of torque and rotation to said propeller pivotal movement vertically and horizontally in relation to said pivotal movement of said drive shaft assembly;
• (e) providing a hydraulic cylinder, said cylinder having a translatable piston positioned within said hydraulic cylinder providing a first cylinder area and a second cylinder area, said piston having a piston rod with a first end attached to said piston and a second end extending outward from said cylinder, said first cylinder area of said hydraulic cylinder having a coiled providing a spring force translating said piston toward said second cylinder area thereby extending said piston rod from said cylinder and lowering said;
• (f) filling said cylinder, including said first and said second cylinder areas, with fluid;
• (g) pivotally attaching said cylinder to said vessel and said second end of said piston rod to said drive shaft assembly housing;
• and
• (h) pivotally raising said pivotally mounting drive shaft assembly by removing fluid from said first cylinder area.

A marine drive system comprising:

• (a) a drive shaft assembly pivotally attached to the stem of a vessel;
• and
• (b) a hydraulic cylinder with an internal spring biased translatable cylinder piston having and attached piston rod, said piston configured between a first fluid filled cylinder chamber retaining a coiled spring and a second fluid cylinder chamber, whereby said piston is urged through said second fluid cylinder chamber to extend said rod from said hydraulic cylinder;
• and
• (c) wherein said hydraulic cylinder and said rod are pivotally attached between said vessel and said drive shaft assembly whereby said extended rod lowers said drive shaft assembly.

A marine drive system comprising:

• (a) a drive shaft assembly pivotally attached to the stem of a vessel;
• and
• (b) a hydraulic cylinder with an internal spring biased translatable cylinder piston having and attached piston rod, said piston configured between a first fluid filled cylinder chamber retaining a coiled spring and a second fluid cylinder chamber, whereby said piston is urged through said second fluid cylinder chamber to extend said rod from said hydraulic cylinder;
• and wherein said hydraulic cylinder and said rod are pivotally attached between said vessel and said drive shaft assembly whereby said extended rod lowers said drive shaft assembly;
• (c) a cylinder flow line fluidly connected to said first fluid filled cylinder chamber and a fluid reserve;
• and
• (d) an electric solenoid valve controlled by a selectively positionable multifunction switch in communication with said cylinder flow line selectively diverting fluid to said fluid reserve from said first fluid filled cylinder thereby reducing fluid pressure in said first fluid filled cylinder to move said piston and compress said spring to retract said rod into said cylinder and raise said drive shaft assembly.

An improved marine drive system for a marine vessel comprising:

• (a) a longitudinally extending drive shaft assembly pivotally attached to a vessel;
• (b) a hydraulic cylinder with a translatable piston and rod pivotally attached between said drive shaft assembly and said vessel;
• (c) a first fluid filled chamber in said cylinder retaining a coiled spring urging said translatable cylinder piston through a second fluid chamber in said cylinder to extend the piston rod from said hydraulic cylinder to lower said drive shaft assembly;
• (d) a first fluid line in communication with a switch controlled valve whereby fluid is selectively evacuated from said first fluid filled chamber to reduce fluid pressure therein thereby moving said piston to compress said spring and retract said rod in response to fluid pressure in said second fluid chamber to raise said drive shaft assembly;
• and
• (e) a second fluid line in communication with a switch controlled valve whereby fluid is selectively removed from the second fluid filed chamber to reduce fluid pressure therein thereby moving said piston in response to said spring to extend said rod to lower said subsequently raised drive shaft assembly.