Automatic trim for power boats

1. An automatic trim system for a power boat having a hull with a transom and a propulsion system including a motor connected to a propeller through a drive, said propeller and drive being adjustable between various trim positions, said system comprising:

at least one trim tab disposed to rotate about a point near a base of the transom of the boat between (a) a position aft of and lower than the bottom of the hull of the boat and (b) a position where the trim tab is substantially out of water and of no adverse effect when the boat is moving above low speed;

first means operable between a first position and a second position and connected to said at least one trim tab so that said at least one trim tab is in said position (a) when said first means is in said first position and is in said position (b) when said first means is in said second position; and

second means responsive to the trim position of said drive to position said first means in said first position when said drive is in the lowest trim position and to position said first means in said second position whenever said drive is in a trim position between a selected pickup trim position and the highest trim position.

2. A system according to claim 1 wherein:

said propulsion system is an outboard motor mounted to the transom by a jack plate;

at least portions of said first and second means are disposed within said jack plate; and

said second means is connected to said motor aft of a tilt tube thereof.

3. A system according to claim 2 wherein:

said second means includes a push tube; and

said first means includes a push rod, a portion of which is within said push tube, and means for causing said push tube to engage said push rod at trim positions of said drive between said pickup trim position and the lowest trim position.

4. A system according to claim 1 wherein:

said second means is a push bar extending horizontally between the drive and the transom and engaged by the drive at said pickup point, said push bar connected to said first means.

5. A system according to claim 1 wherein:

said first means is a slave fluidic cylinder; and

said second means is a master fluidic cylinder in fluid communication with said slave fluidic cylinder.

6. A system according to claim 1 wherein:

said first means is a fluidic cylinder; and

said second means includes (a) a fluid pump connected to said fluidic cylinder, and (b) a position sensor responsive to the trim position of said propeller and drive to provide a position signal indicative thereof;

said pump providing fluid under pressure in response to said position signal.

7. A system according to claim 1 wherein:

said first and second means include first and second rotatable levers and a force transmitting cable extending between said first and second rotatable levers.

8. A system according to claim 1 wherein said second means is responsive to the trim position of said drive to position said first means in positions between said first position and said second position in response to the trim position of said drive being between said lowest trim position and said selected pickup trim position.

9. A system according to claim 1 wherein:

said propeller is disposed on a portion of an outdrive which is rotatable to adjust trim;

said second means is a fluidic master cylinder disposed on said rotatable portion and having a piston rod which engages said transom or a non-rotatable portion of said outdrive at trim positions at or below said pick up point; and

said first means is a fluidic slave cylinder, disposed on a non-rotating portion of said outdrive, in fluid communication with said fluidic master cylinder, and having a cylinder rod attached to said trim tab.

10. A system according to claim 9 wherein:

said cylinders are hydraulic cylinders.

11. A method of operating at least one trim tab on a power boat having a hull with a transom and a propulsion system including a motor connected to a propeller through a drive, said propeller and drive being adjustable between various trim positions independently of any relative motion between the hull and water, said at least one trim tab disposed to rotate about a point near a base of the transom of the boat between (a) a position aft of and lower than the bottom of the hull of the boat and (b) a position where the trim tab is substantially out of water and of no adverse effect when the boat is moving above low speed, said method comprising:

sensing the trim position of said propeller and drive; and

positioning said trim tab, without the aid of relative motion between the hull and water, in direct response to the position of said propeller and drive.

12. Apparatus for operating at least one trim tab on a power boat having a hull with a transom and a propulsion system including a motor connected to a propeller through a drive, said propeller and drive being adjustable between various trim positions independently of any relative motion between the hull and water, said at least one trim tab disposed to rotate about a point near a base of the transom of the boat between (a) a position aft of and lower than the bottom of the hull of the boat and (b) a position where the entire trim tab is substantially out of water and of no adverse effect when the boat is moving above low speed, comprising:

first means for sensing the trim position of said propeller and drive; and

means responsive to said first means for positioning said trim tab, without the aid of relative motion between the hull and water, in direct response to the position of said propeller and drive.

13. A method of operating at least one trim tab on a power boat having a hull with a transom and a propulsion system including a motor connected to a propeller through a drive, said propeller and drive being adjustable between various trim positions by an operator-controlled power driven trim system, said at least one trim tab disposed to rotate about a point near a base of the transom of the boat between (a) a position aft of and lower than the bottom of the hull of the boat and (b) a position where the trim tab is substantially out of water and of no adverse effect when the boat is moving above low speed, said method comprising:

sensing the trim position of said propeller and drive established by said operator-controlled power driven trim system; and

positioning said trim tab in direct response to the trim position of said propeller and drive established by said operator-controlled power driven trim system.

14. Apparatus for operating at least one trim tab on a power boat having a hull with a transom and a propulsion system including a motor connected to a propeller through a drive, said at least one trim tab disposed to rotate about a point near a base of the transom of the boat between (a) a position aft of and lower than the bottom of the hull of the boat and (b) a position where the entire trim tab is substantially out of water and of no adverse effect when the boat is moving above low speed, comprising:

an operator-controlled power driven trim system for adjusting said propeller and drive between various trim positions;

first means for sensing the trim position of said propeller and drive established by said operator-controlled power driven trim system; and

means responsive to said first means for positioning said trim tab in direct response to the trim position of said propeller and drive established by said operator-controlled power driven trim system.

15. A method of operating at least one trim tab on a power boat having a hull with a transom and a propulsion system including a motor connected to a propeller through a drive, said propeller and drive being adjustable between various trim positions from a lowest trim position through a selected pickup trim position distant from said lowest trim position, to a highest trim position distant from said selected pickup trim position, said at least one trim tab disposed to rotate about a point near a base of the transom of the boat between (a) a position aft of and lower than the bottom of the hull of the boat and (b) a position where the trim tab is substantially out of water and of no adverse effect when the boat is moving above low speed, said method comprising:

sensing the trim position of said propeller and drive; and

positioning said trim tab in said position (a) in response to the sensed position of said propeller and drive being said lowest trim position and for positioning said trim tab in said position (b) in response to the sensed position of said propeller and drive being between said selected pickup trim position and said highest trim position.

16. Apparatus for operating at least one trim tab on a power boat having a hull with a transom and a propulsion system including a motor connected to a propeller through a drive, said propeller and drive being adjustable between various trim positions from a lowest trim position through a selected pickup trim position distant from said lowest trim position, to a highest trim position distant from said selected pickup trim position, said at least one trim tab disposed to rotate about a point near a base of the transom of the boat between (a) a position aft of and lower than the bottom of the hull of the boat and (b) a position where the entire trim tab is substantially out of water and of no adverse effect when the boat is moving above low speed, comprising:

first means for sensing the trim position of said propeller and drive; and

means responsive to said first means for positioning said trim tab in said position (a) in response to the sensed position of said propeller and drive being the lowest trim position and for positioning said trim tab in said position (b) in response to the sensed position of said propeller and drive being between a selected pickup trim position and the highest trim position.