Trim and tilt mechanism for outboard propulsion unit

Claim 2

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled in a normally downwardly oriented position with the propeller at the lower end of the unit disposed in wetted position below the water line, and being pivotally movable relative to said transom about a generally horizontal axis upwardly through a range of wetted trim positions and thereafter through a range of tilt positions in which the propeller is raised out of the water, the improvement comprising a combined trim and tilt means including motor means connected to said propulsion unit for pivotally moving the latter upwardly about said axis, operative during the movement of said unit through said trim range to move said unit at a relatively slow angular speed and operative during the movement of said unit through said tilt range to move said unit at a relatively fast angular speed.

Claim 3

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled in a normally downwardly oriented position with the propeller at the lower end of the unit disposed in wetted position below the water line, and being pivotally movable relative to said transom about a generally horizontal axis upwardly through a range of wetted trim positions and thereafter through a range of tilt positions in which the propeller is raised out of the water, the improvement comprising combined trim and tilt means including motor means operative during the upward movement of said unit through said trim range to apply a pivoting force to said unit having a relatively long moment arm and operative during the upward movement of said unit through said tilt range to apply a pivoting force to said unit having a relatively short moment arm.

Claim 4

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled in a normally downwardly oriented position with the propeller at the lower end of the unit disposed in wetted position below the water line, and being pivotally movable relative to said transom about a generally horizontal axis upwardly through a range of wetted trim positions and thereafter through a range of tilt positions in which the propeller is raised out of the water, the improvement comprising combined trim and tilt means including motor means operative during the upward movement of said unit through said trim range to apply a pivoting force to said unit having a relatively long moment arm and operative during the upward movement of said unit through said tilt range to apply a pivoting force to said unit having a relatively short moment arm.

Claim 5

An outboard propulsion system according to claim 2 wherein said motor means includes A. first motor means operative during said trim range movement and acting through said relatively long moment arm; and B. second motor means operative during said tilt range movement and acting through said relatively short moment arm.

Claim 6

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled and being pivotally movable relative to said transom about a generally horizontal axis between a working position in which the propeller at the lower end of the propulsion unit is disposed below the water line to provide propulsion for the boat and a raised position in which the propeller is raised out of the water, the improvement comprising a trim and tilt mechanism for said propulsion unit including A. fluid motor means connected to said propulsion unit for pivotally moving the latter about said axis; B. a source of pressure fluid; C. means for delivering pressure fluid from said source to said motor means; and D. means for varying the effective working area of said fluid motor means as said propulsion unit is moved about said axis by said fluid motor means.

Claim 7

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled and being pivotally movable relative to said transom about a generally horizontal axis between a working position in which the propeller at the lower end of the propulsion unit is disposed below the water line to provide propulsion for the boat and a raised position in which the propeller is raised out of the water, the improvement comprising a trim and tilt mechanism for said propulsion unit including A. fluid motor means connected to said propulsion unit for pivotally moving the latter about said axis; B. a source of pressure fluid; C. means for delivering pressure fluid from said source to said motor means; and D. means for varying the effective working area of said fluid motor means as said propulsion unit is moved about said axis by said fluid motor means.

Claim 8

An outboard propulsion unit according to claim 4 wherein A. said motor means includes first and second fluid motors; and B. said delivery means includes means for routing pressure fluid to said first motor means during the initial portion of the upward movement of said unit from said working position and routing pressure fluid to said second motor means during the subsequent portion of said upward movement.

Claim 9

An outboard propulsion unit according to claim 5 wherein: C. said delivery means is operative to route pressure fluid to both of said motor means during said initial movement portion and is operative to route pressure fluid only to said second motor means during said subsequent movement portion.

Claim 10

An outboard propulsion unit according to claim 5 wherein: C. said first motor means has a relatively large working area and said second motor means has a relatively small working area.

Claim 11

An outboard propulsion unit according to claim 5 wherein C. said first motor means acts on said propulsion unit through a relatively long moment arm and said second motor means acts through a relatively short moment arm.

Claim 12

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled and being pivotally movable relative to said transom about a generally horizontal axis between a working position in which the propeller at the lower end of the propulsion unit is disposed below the water line to provide propulsion for the boat and a raised position in which the propeller is raised out of the water, the improvement comprising a trim and tilt mechanism for said propulsion unit including A. a relatively short stroke hydraulic trim cylinder having engagement at one end with said transom or with a member rigid with said transom and having engagement at its other end with said propulsion unit or with a member pivotally movable about said axis with said unit, said trim cylinder having a stroke only long enough to move said propulsion unit from its working position to an intermediate angular position between said working position and said raised position; and B. a relatively long stroke hydraulic tilt cylinder having engagement at one end with said transom or with a member rigid with said transom and having engagement at its other end with said propulsion unit or with a member pivotally movable about said axis witH said unit, said tilt cylinder having a stroke long enough to pivotally move said propulsion unit from intermediate position to said raised position.

Claim 13

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled and being pivotally movable relative to said transom about a generally horizontal axis between a working position in which the propeller at the lower end of the propulsion unit is disposed below the water line to provide propulsion for the boat and a raised position in which the propeller is raised out of the water, the improvement comprising a trim and tilt mechanism for said propulsion unit including A. a relatively short stroke hydraulic trim cylinder having engagement at one end with said transom or with a member rigid with said transom and having engagement at its other end with said propulsion unit or with a member pivotally movable about said axis with said unit, said trim cylinder having a stroke only long enough to move said propulsion unit from its working position to an intermediate angular position between said working position and said raised position; and B. a relatively long stroke hydraulic tilt cylinder having engagement at one end with said transom or with a member rigid with said transom and having engagement at its other end with said propulsion unit or with a member pivotally movable about said axis witH said unit, said tilt cylinder having a stroke long enough to pivotally move said propulsion unit from intermediate position to said raised position.

Claim 14

An outboard propulsion unit according to claim 9 wherein E. the line of action of said relatively short stroke cylinder with said propulsion unit in said working position is angularly displaced from the line of action of said relatively long stroke cylinder.

Claim 15

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled and being pivotally movable relative to said transom about a generally horizontal axis between a working position in which the propeller at the lower end of the propulsion unit is disposed below the water line to provide propulsion for the board and a raised position in which the propeller is raised out of the water; the improvement comprising a trim and tilt mechanism for said propulsion unit including A. a first hydraulic cylinder having engagement at one end with said transom or with a member rigid with said transom and having engagement at its other end with said propulsion unit or with a member pivotally movable about said axis with said unit; B. a second hydraulic cylinder having engagement at one end with said transom or with a member rigid with said transom and having engagement at its other end with said propulsion unit or with a member pivotally movable about said axis with said unit, the line of action of said first cylinder with said propulsion unit in said working position being angularly displaced from the line of action of said second cylinder with said propulsion unit in said working position.

Claim 16

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled and being pivotally movable relative to said transom about a generally horizontal axis between a working position in which the propeller at the lower end of the propulsion unit is disposed below the water line to provide propulsion for the board and a raised position in which the propeller is raised out of the water; the improvement comprising a trim and tilt mechanism for said propulsion unit including A. a first hydraulic cylinder having engagement at one end with said transom or with a member rigid with said transom and having engagement at its other end with said propulsion unit or with a member pivotally movable about said axis with said unit; B. a second hydraulic cylinder having engagement at one end with said transom or with a member rigid with said transom and having engagement at its other end with said propulsion unit or with a member pivotally movable about said axis with said unit, the line of action of said first cylinder with said propulsion unit in said working position being angularly displaced from the line of action of said second cylinder with said propulsion unit in said working position.

Claim 17

An outboard propulsion unit according to claim 11 wherein D. said first cylinder is a relatively short stroke trim cylinder and said second cylinder is a relatively long stroke tilt cylinder.

Claim 18

An outboard propulsion unit according to claim 12 wherein E. the line of action of said trim cylinder with said propulsion unit in its working position is closer to the horizontal than the line of action of said tilt cylinder.

Claim 19

An outboard propulsion unit according to claim 13 wherein F. the line of action of said trim cylinder with said propulsion unit in its working position is generally horizontal; and G. the line of action of said tilt cylinder with said propulsion unit in its working position is generally vertical.

Claim 20

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled and being pivotally movable relative to said transom about a generally horizontal axis between a small angular range of working positions in which the propeller at the lower end of the propulsion unit is disposed below the water line to provide propulsion for the boat and a raised position in which the propeller is raised out of the water, the improvement comprising a trim and tilt mechanism for said propulsion unit including A. a relatively short stroke hydraulic trim cylinder connected at one end to said transom or to a member rigid with said transom and bearing at its other end against a surface on said propulsion unit or on a member pivotally movable about said axis with said unit, said trim cylinder having a stroke only long enough to move said propulsion unit within said small angular range of working positions and having a line of action generally opposing the line of action of the thrust force generated by said propeller so as to enable the cylinder to effectively overcome the propeller thrust when thus trimming the propulsion unit; and B. a relatively long stroke hydraulic tilt cylinder connected at one end to said transom or to a member rigid with said transom and connected at its other end to said propulsion unit or with a member pivotally movable about said axis with said unit, the connection of said tilt cylinder to said propulsion unit being located closer to said pivot axis than the point of bearing engagement of saiD trim cylinder with said propulsion unit so as to maximize the tilting action of said tilt cylinder and enable it to move said propulsion unit all the way to its raised position.

Claim 21

In an outboard marine propulsion unit adapted to be positioned rearwardly of the transom of the boat to be propelled and being pivotally movable relative to said transom about a generally horizontal axis between a small angular range of working positions in which the propeller at the lower end of the propulsion unit is disposed below the water line to provide propulsion for the boat and a raised position in which the propeller is raised out of the water, the improvement comprising a trim and tilt mechanism for said propulsion unit including A. a relatively short stroke hydraulic trim cylinder connected at one end to said transom or to a member rigid with said transom and bearing at its other end against a surface on said propulsion unit or on a member pivotally movable about said axis with said unit, said trim cylinder having a stroke only long enough to move said propulsion unit within said small angular range of working positions and having a line of action generally opposing the line of action of the thrust force generated by said propeller so as to enable the cylinder to effectively overcome the propeller thrust when thus trimming the propulsion unit; and B. a relatively long stroke hydraulic tilt cylinder connected at one end to said transom or to a member rigid with said transom and connected at its other end to said propulsion unit or with a member pivotally movable about said axis with said unit, the connection of said tilt cylinder to said propulsion unit being located closer to said pivot axis than the point of bearing engagement of saiD trim cylinder with said propulsion unit so as to maximize the tilting action of said tilt cylinder and enable it to move said propulsion unit all the way to its raised position.

Claim 22

An outboard marine propulsion unit according to claim 15 and further including C. a source of pressure fluid; and D. means for routing pressure fluid simultaneously to said trim and tilt cylinders from said pressure fluid source to effect conjoint extension of said cylinders during the initial portion of the upward pivotal movement of said propulsion unit and thereafter, after said trim cylinder has reached the end of its stroke, to effect further extension of said tilt cylinder to move said propulsion unit surface away from said trim cylinder other end and move said propulsion unit to its raised position.