JP2020131908A - Steering device for vessel - Google Patents

Abstract

To restrict steering angle of an outboard engine propelling unit in high speed traveling of a vessel when a hydraulic pressure driving type steering device for having the outboard engine propulsion unit carry out a turning action by using hydraulic pressure.SOLUTION: A first steering angle restriction piston 53 and a second steering angle restriction piston 63 are at least activated so that a restricted state when movement is restricted to stroke end of a first steering angle changing piston 33 and a second steering angle changing piston 43 when vessel speed is equal to or more than vessel speed to be subjected to steering angle restriction. According to the method, steering of an outboard engine propulsion unit is carrying out in a state of having restriction on the steering angle by having a rack and pinion mechanism 71 driven along with reciprocating movement of the first steering angle changing piston 33 and the second steering angle changing piston 43 in a state of having respective movements of the first steering angle changing piston 33 and the second steering angle changing piston 43 restricted to respective stroke ends.SELECTED DRAWING: Figure 4

Description

The present invention relates to a marine steering device.

As a conventional marine steering device, for example, a motor-driven steering device for steering an outboard motor propulsion unit mounted on the outside of a hull with a motor is known. Such a motor-driven steering device is particularly adopted for small vessels, and the steering wheel operation amount of the operator is detected by a sensor, and the motor control unit detects the steering wheel operation amount of the motor based on the steering wheel operation amount detected by the sensor. The steering angle (turning amount) of the outboard motor propulsion unit is controlled by controlling the drive.

By the way, when the ship operator operates the steering wheel greatly while the ship is traveling at high speed, if the steering angle of the outboard motor propulsion unit is controlled based on the amount of the steering wheel operation, the ship makes a large sharp turn. As a result, the running stability of the ship may be impaired. Therefore, when the ship is traveling at high speed, it is necessary to limit the steering angle of the outboard motor propulsion unit so that the ship does not make a sharp turn. For example, in the ship steering device of Patent Document 1, a reaction force motor that gives a reaction force to the steering wheel is provided, and when the ship is traveling at high speed, the reaction force motor is driven to operate the steering wheel of the operator. By making it difficult, the steering angle of the outboard motor propulsion unit is prevented from becoming large during high-speed driving.

Japanese Unexamined Patent Publication No. 2008-126773

By the way, as the size of the hull increases, the outboard motor propulsion unit attached to the outside of the hull also needs to be large, and as a result, the weight of the outboard motor propulsion unit increases. In this case, since the force required to rotate the outboard motor propulsion unit also increases, a hydraulically driven steering device is adopted instead of the motor driven steering device. Even when a hydraulically driven steering device is adopted, the steering angle of the outboard motor propulsion unit is maintained so as not to impair the running stability of the ship when the ship is running at high speed, as in the case of the motor driven steering device. Is required to limit.

The present invention has been made to solve the above problems, and an object of the present invention is to adopt a hydraulically driven marine steering device that swivels an outboard motor propulsion unit using hydraulic pressure. It is an object of the present invention to provide a marine steering device capable of limiting the steering angle of an outboard motor propulsion unit during high-speed traveling.

The marine steering device that solves the above problems is a marine steering device that steers an outboard unit propulsion unit mounted on the outside of the hull, and hydraulic oil is supplied from the first hydraulic pump according to the amount of operation of the handle. A steering angle changing cylinder having a pair of supplied cylinder chambers, a pair of steering angle changing pistons reciprocating in the steering angle changing cylinder by the hydraulic pressure in the pair of cylinder chambers, and the pair of steering angle changing A rack and pinion mechanism that connects the steering angle pistons and drives the pair of steering angle changing pistons to change the steering angle of the outboard unit propulsion unit, and is connected to the steering angle changing cylinder. Each of the steering angle limiting pistons includes a pair of steering angle limiting cylinders each having a steering angle limiting piston that reciprocates with hydraulic oil supplied via a second hydraulic pump. A piston portion that slides in the steering angle limiting cylinder and a piston portion that protrudes from the piston portion and can appear and disappear in each cylinder chamber of the steering angle changing cylinder according to the reciprocating movement of the piston portion. Each of the steering angle limiting pistons has a rod portion, and each of the steering angle limiting pistons has a stroke of each steering angle changing piston by immersing the rod portion in each cylinder chamber of the steering angle changing cylinder. A permissible state that allows movement to the end and a regulated state that regulates the movement of each steering angle changing piston to the stroke end by projecting each rod portion into each cylinder chamber of the steering angle changing cylinder. Each steering angle limiting piston is operated at least so as to be in the restricted state when the ship speed is equal to or higher than a predetermined steering angle limiting applicable ship speed. There is.

According to this, each rod portion of each steering angle limiting piston projects into each cylinder chamber of the steering angle changing cylinder when the ship speed is equal to or higher than a predetermined steering angle limiting applicable ship speed. At least, it is operated so as to be in a regulated state that regulates the movement of each steering angle changing piston to the stroke end. As a result, the rack and pinion mechanism is driven by the reciprocating movement of the pair of steering angle changing pistons while the movement of each steering angle changing piston to the stroke end is restricted, so that the steering angle is restricted. The outboard motor propulsion unit is steered in the performed state. Therefore, when a hydraulically driven marine steering device that swivels the outboard motor propulsion unit using hydraulic pressure is adopted, it is possible to limit the steering angle of the outboard motor propulsion unit during high-speed traveling of the ship. ..

In the ship steering device, it is preferable that each of the steering angle limiting cylinders is provided with a stopper member that limits the stroke range of each steering angle limiting piston.
According to this, for example, by changing the position of the stopper member provided in each steering limiting cylinder, the limiting angle of the steering angle of the outboard motor propulsion unit can be easily adjusted.

In the ship steering device, each of the steering angle limiting pistons may operate so as to switch from the permissible state to the regulated state when the ship speed increases to be equal to or higher than the steering angle limiting applicable ship speed. According to this, when the ship is traveling at a ship speed equal to or higher than a predetermined steering angle limit application ship speed, the steering angle of the outboard motor propulsion unit can be reliably limited.

In the ship steering device, each steering angle limiting piston may operate so as to switch from the allowable state to the regulated state when the position of the accelerator lever is held at the accelerator fully open position.

When the position of the accelerator lever is held in the fully open position of the accelerator, the ship accelerates to reach the maximum speed. Therefore, when the position of the accelerator lever is held at the accelerator fully open position, each steering angle limiting piston regulates the movement from the allowable state that allows the movement of each steering angle changing piston to the stroke end to the stroke end. It operates to switch to the regulated state. According to this, the steering angle of the outboard motor propulsion unit can be limited at an early stage.

According to the present invention, when a hydraulically driven marine steering device that swivels the outboard motor propulsion unit using hydraulic pressure is adopted, the steering angle of the outboard motor propulsion unit is limited during high-speed traveling of the ship. It can be carried out.

The side view which shows typically the ship in embodiment. A plan view schematically showing a ship. The schematic diagram which shows the steering device for a ship. FIG. 5 is a cross-sectional view showing a state in which the first rod portion and the second rod portion protrude into the first steering angle changing cylinder and the second steering angle changing cylinder, respectively. A flowchart for explaining the control of the control device. FIG. 3 is a partial cross-sectional view showing the periphery of the first steering angle limiting cylinder in another embodiment. FIG. 3 is a partial cross-sectional view showing the periphery of the first steering angle limiting cylinder in another embodiment.

Hereinafter, an embodiment embodying a marine steering device will be described with reference to FIGS. 1 to 5.
As shown in FIG. 1, the ship 10 has a hull 11 and an outboard motor propulsion unit 12 mounted on the outside of the hull 11. The outboard motor propulsion unit 12 includes a case 13, an internal combustion engine 14, a steering unit 15, and a swivel unit 16. The internal combustion engine 14 is housed in the case 13. The case 13 is attached to the stern 11e of the hull 11 via a bracket 17. The steering unit 15 is attached to the lower part of the case 13. Further, the swivel unit 16 is attached to the lower part of the steering unit 15. The turning unit 16 can turn with respect to the steering unit 15. The swivel unit 16 has a propeller 16a. The propeller 16a is rotationally driven by the driving force of the internal combustion engine 14. Then, the propulsive force of the ship 10 is generated by the rotation of the propeller 16a. Therefore, the internal combustion engine 14 is a power source of the ship 10 for generating the propulsive force of the ship 10.

As shown in FIG. 2, the ship 10 includes a handle 18, an accelerator lever 19, and a control device 20. The handle 18 and the accelerator lever 19 are provided in the driver's cab in the hull 11. Further, the control device 20 is mounted in the hull 11. Further, the ship 10 includes a speed sensor 21 for detecting the speed of the ship, an angle sensor 22 for detecting the amount of operation of the handle 18, and a position sensor 23 for detecting the position of the accelerator lever 19.

The control device 20 is electrically connected to each of the speed sensor 21, the angle sensor 22, and the position sensor 23. Information about the ship speed detected by the speed sensor 21 is transmitted to the control device 20. Information regarding the amount of operation of the handle 18 detected by the angle sensor 22 is transmitted to the control device 20. The control device 20 stores in advance a program for calculating the steering angle of the outboard motor propulsion unit 12 based on the operation amount of the steering wheel 18 transmitted from the angle sensor 22. Information about the position of the accelerator lever 19 detected by the position sensor 23 is transmitted to the control device 20.

In addition, the ship 10 includes a display 24. The display 24 is provided, for example, in the driver's cab in the hull 11. The display 24 is electrically connected to the control device 20. The display 24 displays information and the like regarding the operation of the ship 10.

As shown in FIG. 3, the ship 10 includes a ship steering device 30 that steers the outboard motor propulsion unit 12. The marine steering device 30 includes a first steering angle changing cylinder 31 and a second steering angle changing cylinder 41 that constitute a steering angle changing cylinder. Further, the ship steering device 30 includes a pair of steering angle limiting cylinders 51, a first steering angle limiting cylinder 51, and a second steering angle limiting cylinder 61. Further, the marine steering device 30 includes a rack and pinion mechanism 71, a first hydraulic pump 81, an oil tank 82, a second hydraulic pump 83, and a switching valve 84.

The first steering angle changing cylinder 31 has a bottomed cylinder-shaped first steering angle changing tube 32 and a flat plate-shaped first steering angle changing piston 33. The first steering angle changing tube 32 has a flat bottom wall 32a and a tubular peripheral wall 32b extending from the outer peripheral portion of the bottom wall 32a in the axial direction of the first steering angle changing tube 32. .. The first steering angle changing piston 33 is housed in the first steering angle changing tube 32 so as to be able to reciprocate in the first steering angle changing tube 32. A first cylinder chamber 34 as a cylinder chamber partitioned by the first steering angle changing piston 33, the bottom wall 32a, and the peripheral wall 32b is formed in the first steering angle changing tube 32. The first cylinder chamber 34 is filled with oil as hydraulic oil. At the end of the peripheral wall 32b on the bottom wall 32a side, a first steering angle changing oil supply / discharge hole 35 communicating with the first cylinder chamber 34 is formed. Further, a through hole 36 penetrating the bottom wall 32a is formed in the central portion of the bottom wall 32a. The axis of the through hole 36 coincides with the axis of the peripheral wall 32b.

The second steering angle changing cylinder 41 has a bottomed cylinder-shaped second steering angle changing tube 42 and a flat plate-shaped second steering angle changing piston 43. The second steering angle changing tube 42 has a flat bottom wall 42a and a tubular peripheral wall 42b extending from the outer peripheral portion of the bottom wall 42a in the axial direction of the second steering angle changing tube 42. .. The second steering angle changing piston 43 is housed in the second steering angle changing tube 42 so as to be able to reciprocate in the second steering angle changing tube 42. A second cylinder chamber 44 as a cylinder chamber partitioned by the second steering angle changing piston 43, the bottom wall 42a, and the peripheral wall 42b is formed in the second steering angle changing tube 42. Therefore, the steering angle changing cylinder has a pair of cylinder chambers. The second cylinder chamber 44 is filled with oil as hydraulic oil. A second steering angle changing oil supply / discharge hole 45 communicating with the second cylinder chamber 44 is formed at the end of the peripheral wall 42b on the bottom wall 42a side. Further, a through hole 46 penetrating the bottom wall 42a is formed in the central portion of the bottom wall 42a. The axis of the through hole 46 coincides with the axis of the peripheral wall 42b.

The first steering angle changing tube 32 and the second steering angle changing tube 42 are arranged so that their axial directions coincide with each other. The first steering angle changing tube 32 and the second steering angle changing tube 42 are arranged so that their openings face each other in the axial directions of the first steering angle changing tube 32 and the second steering angle changing tube 42. Has been done. The first steering angle changing tube 32 and the second steering angle changing tube 42 have their respective openings separated from each other in the axial direction of the first steering angle changing tube 32 and the second steering angle changing tube 42. Have been placed. The first steering angle changing tube 32 and the second steering angle changing tube 42 have the same shape. Further, the first steering angle changing piston 33 and the second steering angle changing piston 43 have the same shape.

The rack and pinion mechanism 71 has an elongated plate-shaped rack 72 and a pinion 73 which is a circular gear. A plurality of rack teeth 72a are provided on one surface of the rack 72. The pinion 73 is meshed with the rack teeth 72a. A tubular connecting shaft 73a is connected to the inner peripheral portion of the pinion 73. One end of the connecting shaft 73a is connected to the pinion 73, and the other end of the connecting shaft 73a is connected to the swivel unit 16.

One end of the rack 72 in the longitudinal direction penetrates into the first steering angle changing tube 32 through the opening of the first steering angle changing tube 32. A first steering angle changing piston 33 is connected to one end of the rack 72 in the longitudinal direction. The other end of the rack 72 in the longitudinal direction enters the second steering angle changing tube 42 through the opening of the second steering angle changing tube 42. A second steering angle changing piston 43 is connected to the other end of the rack 72 in the longitudinal direction. Therefore, the rack 72 of the rack and pinion mechanism 71 connects the first steering angle changing piston 33 and the second steering angle changing piston 43 to each other. The pinion 73 is arranged between the opening end of the first steering angle changing tube 32 and the opening end of the second steering angle changing tube 42.

The first steering angle limiting cylinder 51 has a bottomed tubular first steering angle limiting tube 52 and a first steering angle limiting piston 53. The first steering angle limiting tube 52 has a flat bottom wall 52a and a tubular peripheral wall 52b extending in the axial direction of the first steering angle limiting tube 52 from the outer peripheral portion of the bottom wall 52a. .. The tip of the peripheral wall 52b is connected to the outer surface of the bottom wall 32a of the first steering angle changing tube 32. As a result, the opening of the first steering angle limiting tube 52 is closed by the bottom wall 32a of the first steering angle changing tube 32. The first steering angle limiting tube 52 is connected to the first steering angle changing tube 32 in a state where the axis of the peripheral wall 52b coincides with the axis of the peripheral wall 32b of the first steering angle changing tube 32.

The first steering angle limiting piston 53 is a first piston portion 53a as a piston portion housed in the first steering angle limiting tube 52 and a rod portion provided so as to project from the first piston portion 53a. It has a first rod portion 53b. The first piston portion 53a has a flat plate shape and is housed in the first steering angle limiting tube 52 so as to be able to reciprocate in the first steering angle limiting tube 52. The first piston portion 53a slides in the first steering angle limiting cylinder 51. The first rod portion 53b protrudes from the central portion of the first piston portion 53a and penetrates through the through hole 36 of the bottom wall 32a of the first steering angle changing tube 32. Then, the first rod portion 53b can appear and disappear in the first cylinder chamber 34 of the first steering angle changing cylinder 31 through the through hole 36 in accordance with the reciprocating movement of the first piston portion 53a.

A first steering angle limiting pressure acting chamber 54a is formed in the first steering angle limiting tube 52, which is partitioned by a first piston portion 53a, a bottom wall 52a, and a peripheral wall 52b. Further, in the first steering angle limiting tube 52, a pressure acting chamber 54b for returning the first steering angle is partitioned by a first piston portion 53a, a peripheral wall 52b, and a bottom wall 32a of the first steering angle changing tube 32. Is formed. A first oil supply / discharge hole 55a communicating with the first steering angle limiting pressure action chamber 54a is formed at the end of the peripheral wall 52b on the bottom wall 52a side. Further, a second oil supply / discharge hole 55b is formed at the tip of the peripheral wall 52b so as to communicate with the pressure action chamber 54b for returning the first steering angle.

A first seal member 36s is provided between the through hole 36 and the first rod portion 53b. The first seal member 36s suppresses the flow of oil between the first cylinder chamber 34 and the pressure acting chamber 54b for returning the first steering angle via the through hole 36 and the first rod portion 53b.

A first stopper member 56a is attached to a portion of the inner peripheral surface of the peripheral wall 52b on the tip side of the first oil supply / discharge hole 55a. The first stopper member 56a has a thin flat plate ring shape. The first stopper member 56a is arranged at a position where the surface of the first stopper member 56a located on the bottom wall 52a side is continuous with a part of the inner peripheral surface of the first oil supply / discharge hole 55a. A second stopper member 56b is attached to a portion of the inner peripheral surface of the peripheral wall 52b on the bottom wall 52a side of the second oil supply / discharge hole 55b and on the tip end side of the first stopper member 56a. The second stopper member 56b has a thin flat plate ring shape. The second stopper member 56b has the same shape as the first stopper member 56a. The second stopper member 56b is arranged at a position where the surface of the second stopper member 56b located on the tip end side of the peripheral wall 52b is continuous with a part of the inner peripheral surface of the second oil supply / discharge hole 55b.

The first piston portion 53a is housed in the first steering angle limiting tube 52 so as to be able to reciprocate between the first stopper member 56a and the second stopper member 56b in the first steering angle limiting tube 52. .. Therefore, the first stopper member 56a and the second stopper member 56b are stopper members that limit the stroke range of the first steering angle limiting piston 53.

The second steering angle limiting cylinder 61 has a bottomed tubular second steering angle limiting tube 62 and a second steering angle limiting piston 63. The second steering angle limiting tube 62 has a flat bottom wall 62a and a tubular peripheral wall 62b extending from the outer peripheral portion of the bottom wall 62a in the axial direction of the second steering angle limiting tube 62. .. The tip of the peripheral wall 62b is connected to the outer surface of the bottom wall 42a of the second steering angle changing tube 42. As a result, the opening of the second steering angle limiting tube 62 is closed by the bottom wall 42a of the second steering angle changing tube 42. The second steering angle limiting tube 62 is connected to the second steering angle changing tube 42 in a state where the axis of the peripheral wall 62b coincides with the axis of the peripheral wall 42b of the second steering angle changing tube 42.

The second steering angle limiting piston 63 has a second piston portion 63a as a piston portion accommodated in the second steering angle limiting tube 62 and a rod portion provided so as to project from the second piston portion 63a. It has a second rod portion 63b. The second piston portion 63a has a flat plate shape and is housed in the second steering angle limiting tube 62 so as to be able to reciprocate in the second steering angle limiting tube 62. The second piston portion 63a slides in the second steering angle limiting cylinder 61. The second rod portion 63b projects from the central portion of the second piston portion 63a and penetrates through the through hole 46 of the bottom wall 42a of the second steering angle changing tube 42. Then, the second rod portion 63b can appear and disappear in the second cylinder chamber 44 of the second steering angle changing cylinder 41 through the through hole 46 in accordance with the reciprocating movement of the second piston portion 63a.

In the second steering angle limiting tube 62, a second steering angle limiting pressure acting chamber 64a is formed, which is partitioned by the second piston portion 63a, the bottom wall 62a, and the peripheral wall 62b. Further, in the second steering angle limiting tube 62, the pressure acting chamber 64b for returning the second steering angle is partitioned by the second piston portion 63a, the peripheral wall 62b, and the bottom wall 42a of the second steering angle changing tube 42. Is formed. A third oil supply / discharge hole 65a communicating with the second steering angle limiting pressure action chamber 64a is formed at the end of the peripheral wall 62b on the bottom wall 62a side. A fourth oil supply / discharge hole 65b is formed at the tip of the peripheral wall 62b so as to communicate with the pressure acting chamber 64b for returning the second steering angle.

A second seal member 46s is provided between the through hole 46 and the second rod portion 63b. The second seal member 46s suppresses the flow of oil between the second cylinder chamber 44 and the pressure acting chamber 64b for returning the second steering angle via the through hole 46 and the second rod portion 63b.

A third stopper member 66a is attached to a portion of the inner peripheral surface of the peripheral wall 62b on the tip side of the third oil supply / discharge hole 65a. The third stopper member 66a has a thin flat plate ring shape. The third stopper member 66a is arranged at a position where the surface of the third stopper member 66a located on the bottom wall 62a side is continuous with a part of the inner peripheral surface of the third oil supply / discharge hole 65a. A fourth stopper member 66b is attached to a portion of the inner peripheral surface of the peripheral wall 62b on the bottom wall 62a side of the fourth oil supply / discharge hole 65b and on the tip end side of the third stopper member 66a. The fourth stopper member 66b has a thin flat plate ring shape. The fourth stopper member 66b has the same shape as the third stopper member 66a. The fourth stopper member 66b is arranged at a position where the surface of the fourth stopper member 66b located on the tip end side of the peripheral wall 62b is continuous with a part of the inner peripheral surface of the fourth oil supply / discharge hole 65b.

The second piston portion 63a is housed in the second steering angle limiting tube 62 so as to be able to reciprocate between the third stopper member 66a and the fourth stopper member 66b in the second steering angle limiting tube 62. .. Therefore, the third stopper member 66a and the fourth stopper member 66b are stopper members that limit the stroke range of the second steering angle limiting piston 63.

The first steering angle limiting tube 52 and the second steering angle limiting tube 62 have the same shape. Further, the first steering angle limiting piston 53 and the second steering angle limiting piston 63 have the same shape. The distance between the first stopper member 56a and the second stopper member 56b is the same as the distance between the third stopper member 66a and the fourth stopper member 66b.

The first hydraulic pump 81 is mounted on the hull 11. The first hydraulic pump 81 is connected to the handle 18. The first hydraulic pump 81 is a helm pump driven based on the operation of the handle 18. The marine steering device 30 includes a first steering angle changing oil flow path 81a that connects the first hydraulic pump 81 and the first steering angle changing oil supply / discharge hole 35. Further, the marine steering device 30 includes a second steering angle changing oil flow path 81b that connects the first hydraulic pump 81 and the second steering angle changing oil supply / discharge hole 45. The first steering angle changing oil flow path 81a and the second steering angle changing oil flow path 81b are respectively configured by, for example, piping. Then, oil is supplied from the first hydraulic pump 81 to the first cylinder chamber 34 and the second cylinder chamber 44 according to the amount of operation of the handle 18.

For example, when the handle 18 is operated clockwise, the first hydraulic pump 81 rotates in the normal direction. Then, the first hydraulic pump 81 uses the oil in the first cylinder chamber 34 as the oil supply / discharge hole 35 for changing the first steering angle, the oil flow path 81a for changing the first steering angle, the first hydraulic pump 81, and the second. It is supplied into the second cylinder chamber 44 via the steering angle changing oil flow path 81b and the second steering angle changing oil supply / discharge hole 45. As a result, the hydraulic pressure in the second cylinder chamber 44 overcomes the hydraulic pressure in the first cylinder chamber 34, and the second steering angle changing piston 43 moves in the direction away from the bottom wall 42a and the first steering angle is changed. The piston 33 moves in the direction approaching the bottom wall 32a, and the rack 72 moves in the direction of being immersed in the first steering angle changing tube 32. As the rack 72 moves in the direction of immersion with respect to the first steering angle changing tube 32, the pinion 73 meshed with the rack teeth 72a rotates counterclockwise, and the swivel unit 16 rotates the connecting shaft 73a. Turn counterclockwise through. As a result, the traveling direction of the ship 10 is changed to the right.

For example, when the handle 18 is operated counterclockwise, the first hydraulic pump 81 reverses. Then, the first hydraulic pump 81 uses the oil in the second cylinder chamber 44 as the oil supply / discharge hole 45 for changing the second steering angle, the oil flow path 81b for changing the second steering angle, the first hydraulic pump 81, and the first. It is supplied into the first cylinder chamber 34 via the steering angle changing oil flow path 81a and the first steering angle changing oil supply / discharge hole 35. As a result, the hydraulic pressure in the first cylinder chamber 34 overcomes the hydraulic pressure in the second cylinder chamber 44, and the piston 33 for changing the first steering angle moves in the direction away from the bottom wall 32a and the second steering angle is changed. The piston 43 moves in the direction approaching the bottom wall 42a, and the rack 72 moves in the direction of being immersed in the second steering angle changing tube 42. As the rack 72 moves in the direction of immersion with respect to the second steering angle changing tube 42, the pinion 73 meshed with the rack teeth 72a rotates clockwise, and the swivel unit 16 rotates the connecting shaft 73a. Turn clockwise through. As a result, the traveling direction of the ship 10 is changed to the left.

When the handle 18 is in the neutral position for moving the ship 10 straight, the distance between the first steering angle changing piston 33 and the bottom wall 32a and the distance between the second steering angle changing piston 43 and the bottom wall 42a. It is the same as the distance. The steering wheel 18 is operated clockwise from the neutral position to obtain the distance between the first steering angle changing piston 33 and the bottom wall 32a and the distance between the second steering angle changing piston 43 and the bottom wall 42a. From the same distance, as the first steering angle changing piston 33 approaches the bottom wall 32a, the steering angle of the turning unit 16 in the left direction, that is, in the clockwise direction of the ship 10 becomes larger. Then, when the first steering angle changing piston 33 moves until it comes into contact with the bottom wall 32a, the steering angle of the turning unit 16 in the left direction, that is, in the clockwise direction of the ship 10 becomes the maximum angle. In the present embodiment, the movement of the first steering angle changing piston 33 until it comes into contact with the bottom wall 32a is the movement of the first steering angle changing piston 33 to the stroke end.

The steering wheel 18 is operated counterclockwise from the neutral position to obtain the distance between the first steering angle changing piston 33 and the bottom wall 32a and the distance between the second steering angle changing piston 43 and the bottom wall 42a. From the same distance, as the second steering angle changing piston 43 approaches the bottom wall 42a, the steering angle of the turning unit 16 in the right direction, that is, in the counterclockwise direction of the ship 10 becomes larger. Then, when the second steering angle changing piston 43 moves until it comes into contact with the bottom wall 42a, the steering angle of the turning unit 16 in the right direction, that is, in the counterclockwise direction of the ship 10 becomes the maximum angle. In the present embodiment, the movement of the second steering angle changing piston 43 until it comes into contact with the bottom wall 42a is the movement of the second steering angle changing piston 43 to the stroke end. The maximum steering angle of the turning unit 16 as shown in FIG. 1 is, for example, ± 90 degrees.

Therefore, the first steering angle changing piston 33 and the second steering angle changing piston 43 are the first cylinder chamber 34 and the second cylinder in order to change the steering angle of the turning unit 16, that is, the outboard unit propulsion unit 12. A pair of steering angle changing pistons that reciprocate in the first steering angle changing cylinder 31 and the second steering angle changing cylinder 41 by the hydraulic pressure in the chamber 44. Then, the rack and pinion mechanism 71 is driven by the reciprocating movement of the first steering angle changing piston 33 and the second steering angle changing piston 43 to change the steering angle of the outboard motor propulsion unit 12.

The marine steering device 30 includes a first connection flow path 85 that connects the oil tank 82 and the second hydraulic pump 83. Further, the marine steering device 30 includes a second connection flow path 86 that connects the second hydraulic pump 83 and the switching valve 84. Further, the marine steering device 30 includes a third connection flow path 87 that connects the switching valve 84 and the oil tank 82. The first connection flow path 85, the second connection flow path 86, and the third connection flow path 87 are each configured by, for example, piping.

The marine steering device 30 includes a first steering angle limiting oil flow path 84a that connects the switching valve 84 and the first oil supply / discharge hole 55a. Further, the marine steering device 30 includes a second steering angle limiting oil flow path 84b that connects the switching valve 84 and the second oil supply / discharge hole 55b. The marine steering device 30 includes a third steering angle limiting oil flow path 84c that connects the first steering angle limiting oil flow path 84a and the third oil supply / discharge hole 65a. Further, the ship steering device 30 includes a fourth steering angle limiting oil flow path 84d that connects the second steering angle limiting oil flow path 84b and the fourth oil supply / discharge hole 65b. The second connection flow path 86, the first steering angle limiting oil flow path 84a, the second steering angle limiting oil flow path 84b, the third steering angle limiting oil flow path 84c, and the fourth steering angle limiting oil flow path The 84d constitutes a hydraulic pipe 88 that connects the second hydraulic pump 83, the first steering angle limiting cylinder 51, and the second steering angle limiting cylinder 61. The switching valve 84 is provided in the hydraulic pipe 88.

Oil as hydraulic oil is stored in the oil tank 82. The second hydraulic pump 83 is driven by the power of the internal combustion engine 14. Then, when the second hydraulic pump 83 is driven by the power of the internal combustion engine 14, the oil stored in the oil tank 82 passes through the first connection flow path 85, the second hydraulic pump 83, and the second connection flow path 86. It is supplied to the switching valve 84 via.

The switching valve 84 is electrically connected to the control device 20. The switching valve 84 is a solenoid valve that operates based on a command signal output from the control device 20. The control device 20 stores in advance a program for generating a command signal for operating the switching valve 84. The command signal for operating the switching valve 84 is generated from information regarding the amount of operation of the steering wheel 18, the position of the accelerator lever 19, and the ship speed.

The switching valve 84 allows the oil supplied from the second hydraulic pump 83 via the second connection flow path 86 to flow to the first steering angle limiting oil flow path 84a, and the second steering angle limiting oil. It is configured to be switchable to the first valve switching state that allows the flow of oil from the flow path 84b to the third connection flow path 87. Further, the switching valve 84 allows the oil supplied from the second hydraulic pump 83 via the second connection flow path 86 to flow to the oil flow path 84b for limiting the second steering angle, and limits the first steering angle. It is configured to be switchable to a second valve switching state that allows the flow of oil from the oil flow path 84a to the third connection flow path 87. Further, the switching valve 84 is connected to the first steering angle limiting oil flow path 84a and the second steering angle limiting oil flow path 84b in the oil supplied from the second hydraulic pump 83 via the second connecting flow path 86, respectively. It is configured to be switchable to a third valve switching state that shuts off the flow of the oil and allows the oil supplied from the second connection flow path 86 to flow to the third connection flow path 87. The switching valve 84 is configured to be switchable to three valve switching states of a first valve switching state, a second valve switching state, and a third valve switching state by a command signal from the control device 20.

The control device 20 stores in advance a program that performs a mode execution process without steering angle limitation. Further, the control device 20 stores in advance a program for executing the mode execution process with steering angle limitation. Further, the control device 20 stores in advance a program for determining whether or not to perform the mode execution process with steering angle limitation.

For example, when the control device 20 is performing the steering angle unlimited mode execution process, it is determined by the determination process that the steering angle limited mode execution process is to be performed, and the steering angle is changed from the steering angle unlimited mode execution process. When switching to the restricted mode execution process, the operation of the switching valve 84 is controlled so that the switching valve 84 switches to the first valve switching state. Then, the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connection flow path 86 is allowed to flow to the first steering angle limiting oil flow path 84a, and the second steering angle limiting The flow of oil from the oil flow path 84b to the third connection flow path 87 via the switching valve 84 is allowed.

As shown in FIG. 4, when the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connecting flow path 86 flows to the first steering angle limiting oil flow path 84a, the first steering angle limiting Oil is supplied into the first steering angle limiting pressure acting chamber 54a through the oil flow path 84a and the first oil supply / discharge hole 55a. Then, the first piston portion 53a receives the hydraulic pressure in the pressure acting chamber 54a for limiting the first steering angle and moves from the first stopper member 56a toward the second stopper member 56b, and the first rod portion 53b moves. It projects into the first steering angle changing cylinder 31 through the through hole 36. Further, with the movement of the first piston portion 53a from the first stopper member 56a to the second stopper member 56b, the oil in the pressure acting chamber 54b for returning the first steering angle is transferred to the second oil supply / discharge holes 55b and the second. 2 The oil is returned to the oil tank 82 via the steering angle limiting oil flow path 84b, the switching valve 84, and the third connection flow path 87.

Further, when the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connection flow path 86 flows to the first steering angle limiting oil flow path 84a, the first steering angle limiting oil flow path 84a Oil is supplied into the second steering angle limiting pressure acting chamber 64a through the third steering angle limiting oil flow path 84c and the third oil supply / discharge hole 65a. Then, the second piston portion 63a receives the hydraulic pressure in the pressure acting chamber 64a for limiting the second steering angle and moves from the third stopper member 66a toward the fourth stopper member 66b, and the second rod portion 63b moves. It projects into the second steering angle changing cylinder 41 through the through hole 46. Further, with the movement of the second piston portion 63a from the third stopper member 66a toward the fourth stopper member 66b, the oil in the pressure acting chamber 64b for returning the second steering angle becomes the fourth oil supply / discharge hole 65b, the second. 4 The oil is returned to the oil tank 82 via the steering angle limiting oil flow path 84d, the second steering angle limiting oil flow path 84b, the switching valve 84, and the third connecting flow path 87.

The movement of the first piston portion 53a from the first stopper member 56a to the second stopper member 56b and the movement of the second piston portion 63a from the third stopper member 66a to the fourth stopper member 66b are synchronized with each other. Will be done. Therefore, the timing of separating from the first stopper member 56a of the first piston portion 53a and the timing of separating from the third stopper member 66a of the second piston portion 63a are the same. Further, the timing of contacting the second stopper member 56b of the first piston portion 53a is the same as the timing of contacting the fourth stopper member 66b of the second piston portion 63a. Therefore, the time required for the first piston portion 53a to move from the first stopper member 56a to the second stopper member 56b and the time required for the second piston portion 63a to move from the third stopper member 66a to the fourth stopper member 66b. It is the same as the time required.

The first rod portion 53b protruding into the first steering angle changing cylinder 31 regulates the movement of the first steering angle changing piston 33 to the stroke end by abutting with the first steering angle changing piston 33. .. Therefore, during the mode execution process with steering angle limitation, the first steering angle changing piston 33 does not abut on the bottom wall 32a, so that the steering angle of the turning unit 16 in the left direction, that is, in the clockwise direction of the ship 10 is set. It will be in a restricted state.

Further, the second rod portion 63b protruding into the second steering angle changing cylinder 41 comes into contact with the second steering angle changing piston 43 to move the second steering angle changing piston 43 to the stroke end. regulate. Therefore, during the mode execution process with steering angle limitation, the second steering angle changing piston 43 does not abut on the bottom wall 42a, so that the steering angle of the turning unit 16 in the right direction, that is, in the counterclockwise direction of the ship 10 is set. It will be in a restricted state.

Therefore, the first steering angle limiting piston 53 and the second steering angle limiting piston 63 are the first steering angle limiting tube 52 and the second steering angle limiting tube 52 in order to limit the steering angle of the turning unit 16, that is, the outboard motor propulsion unit 12. 2 Steering angle limiting tube 62 A steering angle limiting piston that reciprocates inside each of the tubes 62.

Then, in the control device 20, when the first piston portion 53a abuts on the second stopper member 56b and the second piston portion 63a abuts on the fourth stopper member 66b, the switching valve 84 switches to the third valve switching state. Controls the operation of the switching valve 84. Then, the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connection flow path 86 is supplied to the first steering angle limiting oil flow path 84a and the second steering angle limiting oil flow path 84b, respectively. The flow is cut off, and the oil supplied from the second connection flow path 86 to the switching valve 84 is allowed to flow to the third connection flow path 87. As a result, the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connection flow path 86 is returned to the oil tank 82 via the third connection flow path 87.

Then, the hydraulic pressure in the first steering angle limiting pressure acting chamber 54a and the hydraulic pressure in the first steering angle returning pressure acting chamber 54b are maintained, and in the second steering angle limiting pressure acting chamber 64a. The balance between the hydraulic pressure and the hydraulic pressure in the pressure acting chamber 64b for returning the second steering angle is maintained. As a result, the first rod portion 53b protrudes into the first steering angle changing cylinder 31 and the second rod portion 63b protrudes into the second steering angle changing cylinder 41 for limiting the first steering angle. The positions of the piston 53 and the second steering angle limiting piston 63 are held.

For example, when the control device 20 is performing the steering angle limited mode execution process, it is determined by the determination process that the steering angle unrestricted mode execution process is to be performed, and the steering angle is changed from the steering angle limited mode execution process. When switching to the unrestricted mode execution process, the operation of the switching valve 84 is controlled so that the switching valve 84 switches to the second valve switching state. Then, the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connection flow path 86 is allowed to flow to the second steering angle limiting oil flow path 84b, and the first steering angle limiting The flow of oil from the oil flow path 84a to the third connection flow path 87 via the switching valve 84 is allowed.

As shown in FIG. 3, when the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connecting flow path 86 flows to the second steering angle limiting oil flow path 84b, the second steering angle limiting Oil is supplied into the pressure acting chamber 54b for returning the steering angle through the oil flow path 84b and the second oil supply / discharge hole 55b. Then, the first piston portion 53a receives the hydraulic pressure in the pressure action chamber 54b for returning the first steering angle and moves from the second stopper member 56b toward the first stopper member 56a, and the first rod portion 53b moves. Immerse yourself in the inside of the first steering angle changing cylinder 31. Further, as the first piston portion 53a moves from the second stopper member 56b toward the first stopper member 56a, the oil in the first steering angle limiting pressure acting chamber 54a becomes the first oil supply / discharge holes 55a and the first. 1 The oil is returned to the oil tank 82 via the steering angle limiting oil flow path 84a, the switching valve 84, and the third connection flow path 87.

Further, when the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connection flow path 86 flows to the second steering angle limiting oil flow path 84b, the second steering angle limiting oil flow path 84b Oil is supplied into the second steering angle return pressure acting chamber 64b via the fourth steering angle limiting oil flow path 84d and the fourth oil supply / discharge hole 65b. Then, the second piston portion 63a receives the hydraulic pressure in the pressure action chamber 64b for returning the second steering angle and moves from the fourth stopper member 66b toward the third stopper member 66a, and the second rod portion 63b moves. Immerse yourself in the inside of the second steering angle changing cylinder 41. Further, as the oil in the second steering angle limiting pressure acting chamber 64a moves from the fourth stopper member 66b to the third stopper member 66a in the second piston portion 63a, the oil in the third oil supply / discharge hole 65a and the third oil supply / discharge hole 65a 3 The oil is returned to the oil tank 82 via the steering angle limiting oil flow path 84c, the first steering angle limiting oil flow path 84a, the switching valve 84, and the third connecting flow path 87.

The movement of the first piston portion 53a from the second stopper member 56b toward the first stopper member 56a and the movement of the second piston portion 63a from the fourth stopper member 66b toward the third stopper member 66a are synchronized with each other. Will be done. Therefore, the timing of separating from the second stopper member 56b in the first piston portion 53a and the timing of separating from the fourth stopper member 66b in the second piston portion 63a are the same. Further, the timing of contacting the first stopper member 56a of the first piston portion 53a is the same as the timing of contacting the third stopper member 66a of the second piston portion 63a. Therefore, the time required for the first piston portion 53a to move from the second stopper member 56b to the first stopper member 56a and the time required for the second piston portion 63a to move from the fourth stopper member 66b to the third stopper member 66a. It is the same as the time required.

When the first piston portion 53a moves until it comes into contact with the first stopper member 56a and the first rod portion 53b is most immersed in the first steering angle changing cylinder 31, the tip of the first rod portion 53b Is in a state of not protruding from the through hole 36 into the first steering angle changing cylinder 31. Therefore, the first rod portion 53b immersed in the inside of the first steering angle changing cylinder 31 allows the first steering angle changing piston 33 to move to the stroke end. Therefore, since the first steering angle changing piston 33 can come into contact with the bottom wall 32a during the steering angle unlimited mode execution process, the steering angle of the turning unit 16 in the left direction, that is, in the clockwise direction of the ship 10. The restriction of is released.

When the second piston portion 63a moves until it comes into contact with the third stopper member 66a and the second rod portion 63b is most immersed in the second steering angle changing cylinder 41, the tip of the second rod portion 63b Is in a state of not protruding from the through hole 46 into the second steering angle changing cylinder 41. Therefore, the second rod portion 63b immersed in the inside of the second steering angle changing cylinder 41 allows the second steering angle changing piston 43 to move to the stroke end. Therefore, since the second steering angle changing piston 43 can come into contact with the bottom wall 42a during the steering angle unlimited mode execution process, the steering angle of the turning unit 16 in the right direction, that is, in the counterclockwise direction of the ship 10. The restriction of is released.

Therefore, the second hydraulic pump 83 supplies and discharges oil to the first steering angle limiting cylinder 51 and the second steering angle limiting cylinder 61, respectively, and supplies and discharges the first steering angle limiting piston 53 and the second steering angle limiting piston, respectively. Each of 63 is reciprocated. The switching valve 84 allows the first steering angle limiting piston 53 and the second steering angle limiting piston 63 to move to the stroke end of the first steering angle changing piston 33 and the second steering angle changing piston 43. Performs an operation to switch to the allowable state. Further, the switching valve 84 moves the first steering angle limiting piston 53 and the second steering angle limiting piston 63 to the stroke ends of the first steering angle changing piston 33 and the second steering angle changing piston 43. Performs an operation to switch to the regulated state. Therefore, the switching valve 84 operates to switch between the allowable state and the restricted state, and the first steering angle limiting piston 53 and the second steering angle limiting piston 63 are in the allowable state and the restricted state. It is possible to switch to both. Then, the switching valve 84 switches the supply and discharge of oil to each of the first steering angle limiting cylinder 51 and the second steering angle limiting cylinder 61 in the second hydraulic pump 83. Therefore, the first steering angle limiting cylinder 51 and the second steering angle limiting cylinder 61 are double-acting cylinders.

When the first piston portion 53a abuts on the first stopper member 56a and the second piston portion 63a abuts on the third stopper member 66a, the control device 20 switches so that the switching valve 84 switches to the third valve switching state. Controls the operation of the valve 84. Then, the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connection flow path 86 is supplied to the first steering angle limiting oil flow path 84a and the second steering angle limiting oil flow path 84b, respectively. The flow is cut off, and the oil supplied from the second connection flow path 86 to the switching valve 84 is allowed to flow to the third connection flow path 87. As a result, the oil supplied from the second hydraulic pump 83 to the switching valve 84 via the second connection flow path 86 is returned to the oil tank 82 via the third connection flow path 87.

Then, the hydraulic pressure in the first steering angle limiting pressure acting chamber 54a and the hydraulic pressure in the first steering angle returning pressure acting chamber 54b are maintained, and in the second steering angle limiting pressure acting chamber 64a. The balance between the hydraulic pressure and the hydraulic pressure in the pressure acting chamber 64b for returning the second steering angle is maintained. As a result, the first steering angle is immersed in the first steering angle changing cylinder 31 and the second rod portion 63b is immersed in the second steering angle changing cylinder 41. The positions of the limiting piston 53 and the second steering angle limiting piston 63 are held.

The control device 20 stores the steering angle limitation value α, the steering angle limitation application ship speed V, and the steering angle limitation piston operation completion time T as preset parameters. The steering angle limit value α is an upper limit value of the steering angle of the outboard unit propulsion unit 12 that is allowed when the control device 20 is executing the mode with steering angle limitation. For example, when the first piston portion 53a is in contact with the second stopper member 56b and the first steering angle changing piston 33 and the first rod portion 53b are in contact with each other, the outboard motor propulsion unit 12 moves to the left. The steering angle of is the steering angle limit value α. Further, for example, when the second piston portion 63a is in contact with the fourth stopper member 66b and the second steering angle changing piston 43 and the second rod portion 63b are in contact with each other, the right side of the outboard motor propulsion unit 12 The steering angle in the direction is the steering angle limit value α.

The steering angle limitation application ship speed V is a predetermined ship speed, and is used for determining whether or not to perform the steering angle limitation mode execution process when the control device 20 is executing the determination process. Then, when the ship speed increases to the ship speed V or higher to which the steering angle limit is applied, the control device 20 causes the first rod portion 53b and the second rod portion 63b to move into the first steering angle changing cylinder 31 and the second steering. A program for controlling the operation of the switching valve 84 is stored in advance so that each of the angle changing cylinders 41 protrudes into the cylinder 41. Therefore, the first steering angle limiting piston 53 and the second steering angle limiting piston 63 have the first steering angle changing piston 33 and the second steering when the ship speed increases and becomes equal to or higher than the steering angle limiting applicable ship speed V. It operates so as to switch from an allowable state that allows movement of the angle changing piston 43 to the stroke end to a regulated state that restricts movement to the stroke end. The control device 20 is a control unit that controls the operation of the switching valve 84 according to the ship speed.

The steering angle limiting piston operation completion time T is the time required for the first piston portion 53a to move from the first stopper member 56a to the second stopper member 56b, or the first piston portion 53a from the second stopper member 56b to the second. 1 This is the time required to move to the stopper member 56a. The steering angle limiting piston operation completion time T is the time required for the second piston portion 63a to move from the third stopper member 66a to the fourth stopper member 66b, or the second piston portion 63a is the fourth stopper member 66b. It is also the time required to move from the third stopper member 66a to the third stopper member 66a.

Further, when the position of the accelerator lever 19 is held in the control device 20 at the accelerator fully open position, the first rod portion 53b and the second rod portion 63b change the inside of the first steering angle changing cylinder 31 and the second steering angle. A program for controlling the operation of the switching valve 84 so as to protrude into the cylinder 41 is stored in advance. Therefore, when the position of the accelerator lever 19 is held at the accelerator fully open position, the first steering angle limiting piston 53 and the second steering angle limiting piston 63 change the first steering angle changing piston 33 and the second steering angle. It operates so as to switch from an allowable state that allows movement of the piston 43 to the stroke end to a regulated state that restricts movement to the stroke end.

When the position of the accelerator lever 19 is held in the fully open position of the accelerator, the ship 10 accelerates to reach the maximum speed. Therefore, the first steering angle limiting piston 53 and the second steering angle limiting piston 63 have the first steering angle changing piston 33 and the second steering when the ship speed is equal to or higher than the steering angle limiting applicable ship speed V. At least, it is operated so as to be in a regulated state that restricts the movement of the angle changing piston 43 to the stroke end.

Further, the control device 20 has a timer function for measuring the time when the first piston portion 53a and the second piston portion 63a start to move. The control device 20 is a program that measures the movement time of the first piston portion 53a and the second piston portion 63a as the steering angle change elapsed time when the first piston portion 53a and the second piston portion 63a start to move. Is stored in advance.

Next, the operation of this embodiment will be described.
As shown in FIG. 5, the control device 20 first makes initial settings in step S11. As an initial setting, the control device 20 performs the steering angle limitless mode execution process, sets the steering angle change elapsed time to "0", and further sets the steering angle limit exceeding flag to "0". Next, in step S12, the control device 20 has information on the ship speed detected by the speed sensor 21, information on the operating amount of the steering wheel 18 detected by the angle sensor 22, and the accelerator lever 19 detected by the position sensor 23. Receive information about the location of each.

Next, in step S13, the control device 20 determines whether or not the ship speed detected by the speed sensor 21 is equal to or higher than the steering angle limit application ship speed V. When the control device 20 determines in step S13 that the ship speed is not equal to or higher than the steering angle limiting application ship speed V, the control device 20 proceeds to step S14, and the position of the accelerator lever 19 detected by the position sensor 23 in step S14 is the accelerator fully open position. It is determined whether or not it is. When the control device 20 determines in step S14 that the position of the accelerator lever 19 is not the fully open position of the accelerator, the control device 20 proceeds to step S15 and determines in step S15 whether or not the mode execution process with steering angle limitation is being performed.

When the control device 20 determines that the steering angle limited mode execution process is being performed in step S15, the control device 20 proceeds to step S16 and sets the steering angle change elapsed time to "0" in step S16. Then, the control device 20 performs the steering angle unlimited mode execution process in step S17. On the other hand, if the control device 20 determines in step S15 that the steering angle limited mode execution process has not been performed, the control device 20 proceeds to step S17.

Next, in step S18, the control device 20 determines whether or not the steering angle change elapsed time is equal to or longer than the steering angle limiting piston operation completion time T. If the control device 20 determines in step S18 that the elapsed steering angle change time is not equal to or greater than the steering angle limiting piston operation completion time T, the process proceeds to step S19, and the switching valve 84 is in the second valve switching state in step S19. The operation of the switching valve 84 is controlled as described above. Further, the control device 20 controls the operation of the switching valve 84 so that the switching valve 84 is in the second valve switching state in step S19, and at the same time, measures the steering angle change elapsed time. Then, in step S20, the control device 20 includes information on the steering angle limitation status for notifying whether the current mode execution processing status is the steering angle limitation-free mode execution processing or the steering angle limitation mode execution processing, and the current mode execution processing. The steering angle of the outboard motor propulsion unit 12 and the steering angle of the outboard motor propulsion unit 12 are output to the display 24. After that, the control device 20 shifts to step S12 and repeats the processes after step S12.

On the other hand, when the control device 20 determines in step S18 that the elapsed steering angle change time is equal to or longer than the steering angle limiting piston operation completion time T, the process proceeds to step S21, and the switching valve 84 is in the third valve switching state in step S21. The operation of the switching valve 84 is controlled so as to be. As a result, the first steering angle 53b is immersed in the first steering angle changing cylinder 31 and the second rod portion 63b is immersed in the second steering angle changing cylinder 41. The positions of the limiting piston 53 and the second steering angle limiting piston 63 are maintained, and the steering angle of the outboard motor propulsion unit 12 is not limited. Then, the control device 20 shifts to step S20.

On the other hand, if the control device 20 determines in step S13 that the ship speed is equal to or higher than the steering angle limit application ship speed V, the control device 20 proceeds to step S22, and whether or not the steering angle limitless mode execution process is performed in step S22. Alternatively, it is determined whether or not the steering angle limit exceeding flag is "0". Further, when the control device 20 determines in step S14 that the position of the accelerator lever 19 is the accelerator fully open position, the control device 20 proceeds to step S22.

In steps S13 and S14, the mode execution process with steering angle limitation is performed based on the information on the ship speed received by the control device 20 in step S12, the information on the operation amount of the steering wheel 18, and the information on the position of the accelerator lever 19. This is a determination process in which the control device 20 determines whether or not.

When the control device 20 determines that the steering angle limit-free mode execution process is being performed in step S22 or the steering angle limit exceeding flag is "0", the control device 20 proceeds to step S23, and the steering angle change elapsed time in step S23. Is set to "0". Then, the control device 20 performs the steering angle limited mode execution process in step S24. On the other hand, if the control device 20 determines in step S22 that the steering angle limitless mode execution process has not been performed or the steering angle limit exceeding flag is not "0", the control device 20 proceeds to step S24.

Next, in step S25, the control device 20 determines whether or not the absolute value of the steering angle of the outboard motor propulsion unit 12 is larger than the steering angle limit value α. When the control device 20 determines in step S25 that the absolute value of the steering angle of the outboard motor propulsion unit 12 is larger than the steering angle limit value α, the control device 20 proceeds to step S26 and sets the steering angle limit exceeding flag to "1" in step S26. ". Then, the control device 20 outputs a warning display to the display 24 so that the steering angle of the outboard motor propulsion unit 12 is set to the steering angle limit value α or less in step S27.

Next, the control device 20 controls the operation of the switching valve 84 so that the switching valve 84 is in the first valve switching state in step S28. Further, the control device 20 controls the operation of the switching valve 84 so that the switching valve 84 is in the first valve switching state in step S28, and at the same time, measures the steering angle change elapsed time. Then, the control device 20 shifts to step S20, and in step S20, the information regarding the current steering angle limitation status and the current steering angle of the outboard motor propulsion unit 12 are output to the display 24. After that, the control device 20 shifts to step S12 and repeats the processes after step S12.

On the other hand, if the control device 20 determines in step S25 that the absolute value of the steering angle of the outboard motor propulsion unit 12 is not larger than the steering angle limit value α, the process proceeds to step S29, and in step S29, the steering angle limit exceeding flag Is set to "0". Then, in step S30, the control device 20 determines whether or not the steering angle change elapsed time is equal to or longer than the steering angle limiting piston operation completion time T.

If the control device 20 determines in step S30 that the elapsed steering angle change time is not equal to or greater than the steering angle limiting piston operation completion time T, the control device 20 proceeds to step S28 and performs the processes after step S28. On the other hand, if it is determined in step S30 that the elapsed steering angle change time is equal to or longer than the steering angle limiting piston operation completion time T, the process proceeds to step S21, and in step S21, the switching valve 84 is in the third valve switching state. Controls the operation of 84. As a result, the first rod portion 53b protrudes into the first steering angle changing cylinder 31, and the second rod portion 63b protrudes into the second steering angle changing cylinder 41 for limiting the first steering angle. The positions of the piston 53 and the second steering angle limiting piston 63 are maintained, and the steering angle of the outboard motor propulsion unit 12 is limited.

In the above embodiment, the following effects can be obtained.
(1) The first steering angle limiting piston 53 and the second steering angle limiting piston 63 are the first steering angle changing piston 33 and the second steering angle changing piston 33 when the ship speed is equal to or higher than the steering angle limiting applicable ship speed V. At least, it is operated so as to be in a regulated state that restricts the movement of the steering angle changing piston 43 to the stroke end. Then, in a state where the movement of the first steering angle changing piston 33 and the second steering angle changing piston 43 to the stroke ends is restricted, the first steering angle changing piston 33 and the second steering angle changing piston 43 are restricted. The rack and pinion mechanism 71 is driven by the reciprocating movement of the outboard motor, so that the outboard motor propulsion unit 12 is steered while the steering angle is limited. Therefore, when the hydraulically driven marine steering device 30 that swivels the outboard motor propulsion unit 12 using hydraulic pressure is adopted, the steering angle of the outboard motor propulsion unit 12 is limited when the ship 10 is traveling at high speed. It can be carried out.

(2) In the first steering angle limiting cylinder 51, a first stopper member 56a and a second stopper member 56b that limit the stroke range of the first steering angle limiting piston 53 are provided, and a second steering angle is provided. A third stopper member 66a and a fourth stopper member 66b that limit the stroke range of the second steering angle limiting piston 63 are provided in the limiting cylinder 61. According to this, the positions of the first stopper member 56a and the second stopper member 56b provided in the first steering angle limiting cylinder 51 are changed, and the third stopper provided in the second steering angle limiting cylinder 61 is changed. By changing the positions of the member 66a and the fourth stopper member 66b, the limiting angle of the steering angle of the outboard motor propulsion unit 12 can be easily adjusted.

(3) The first steering angle limiting piston 53 and the second steering angle limiting piston 63 have the first steering angle changing piston 33 and the second steering angle changing piston 33 when the ship speed increases and becomes equal to or higher than the steering angle limiting applicable ship speed V. It operates so as to switch from an allowable state that allows movement of the steering angle changing piston 43 to the stroke end to a regulated state that restricts movement to the stroke end. According to this, when the ship 10 is traveling at a ship speed V or higher to which the steering angle limitation is applied, the steering angle of the outboard motor propulsion unit 12 can be surely limited.

(4) When the position of the accelerator lever 19 is held in the fully open position of the accelerator, the ship 10 accelerates and reaches the maximum speed. Therefore, when the position of the accelerator lever 19 is held at the fully open position of the accelerator, the first steering angle limiting piston 53 and the second steering angle limiting piston 63 change the first steering angle changing piston 33 and the second steering angle. It operates so as to switch from an allowable state that allows movement of the piston 43 to the stroke end to a regulated state that restricts movement to the stroke end. As a result, the steering angle of the outboard motor propulsion unit 12 can be limited at an early stage.

(5) The control device 20 controls the operation of the switching valve 84 so that the switching valve 84 is in the third valve switching state, so that the first steering angle limiting piston 53 and the second steering angle limiting piston 63 are respectively. The position of is retained. As a result, it is possible to prevent a load from being applied to each of the first stopper member 56a, the second stopper member 56b, the third stopper member 66a, and the fourth stopper member 66b.

(6) According to the marine steering device 30 of the present embodiment, the outboard motor propulsion unit 12 can be steered using hydraulic pressure, so that even when the outboard motor propulsion unit 12 is heavy. , The outboard motor propulsion unit 12 can be easily steered.

(7) According to the marine steering device 30 of the present embodiment, it is not necessary to provide a reaction force motor that gives a reaction force to the handle 18 as in the prior art, so that the configuration on the hull 11 side is restricted. Can be suppressed.

The above embodiment can be modified and implemented as follows. The above-described embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

○ As shown in FIG. 6, the first rod portion 53b is the first steering angle between the bottom wall 52a of the first steering angle limiting tube 52 and the first piston portion 53a of the first steering angle limiting piston 53. A tension spring 91 that urges the first steering angle limiting piston 53 in the direction of immersion in the changing cylinder 31 may be provided. According to this, when the mode execution process with steering angle limitation is switched to the mode execution process without steering angle limitation, the first rod portion 53b is moved into the first steering angle changing cylinder 31 by the urging force of the tension spring 91. On the other hand, the first steering angle limiting piston 53 can be smoothly moved in the immersive direction. In this case, the second rod portion 63b is also used for changing the second steering angle between the bottom wall 62a of the second steering angle limiting tube 62 and the second piston portion 63a of the second steering angle limiting piston 63. A tension spring 91 that urges the second steering angle limiting piston 63 in the direction of immersion in the cylinder 41 may be provided.

○ In the embodiment, the first rod portion 53b is a cylinder for changing the first steering angle between the bottom wall 52a of the first steering angle limiting tube 52 and the first piston portion 53a of the first steering angle limiting piston 53. An urging spring may be provided to urge the first steering angle limiting piston 53 in the direction of protrusion into the 31. According to this, when the mode execution process with no steering angle limitation is switched to the mode execution processing with steering angle limitation, the first rod portion 53b is moved into the first steering angle changing cylinder 31 by the urging force of the urging spring. The first steering angle limiting piston 53 can be smoothly moved in the protruding direction. In this case, the second rod portion 63b is also used for changing the second steering angle between the bottom wall 62a of the second steering angle limiting tube 62 and the second piston portion 63a of the second steering angle limiting piston 63. An urging spring may be provided to urge the second steering angle limiting piston 63 in the direction of protrusion into the cylinder 41.

○ As shown in FIG. 7, an annular flange 92 may be provided at the tip of the first rod portion 53b. According to this, the contact area of the first rod portion 53b with the first steering angle changing piston 33 is larger than that in the case where the flange 92 is not provided at the tip of the first rod portion 53b. It is possible to easily regulate the movement of the steering angle changing piston 33 to the stroke end. An annular flange 92 may also be provided at the tip of the second rod portion 63b.

○ In the embodiment, the marine steering device 30 may have a configuration in which the first stopper member 56a, the second stopper member 56b, the third stopper member 66a, and the fourth stopper member 66b are deleted. In this case, the first piston portion 53a moves between the bottom wall 52a of the first steering angle limiting tube 52 and the bottom wall 32a of the first steering angle changing tube 32. Further, the second piston portion 63a moves between the bottom wall 62a of the second steering angle limiting tube 62 and the bottom wall 42a of the second steering angle changing tube 42. In this case, when the first piston portion 53a is in contact with the bottom wall 52a or the first piston portion 53a is in contact with the bottom wall 32a, the first oil supply / discharge hole 55a or the second oil supply is supplied. It is preferable that a notch is formed on the entire circumference of the corner portion of the first piston portion 53a so that oil can be easily supplied and discharged from the drain hole 55b. Further, in a state where the second piston portion 63a is in contact with the bottom wall 62a or a state in which the second piston portion 63a is in contact with the bottom wall 42a, the third oil supply / discharge hole 65a or the fourth oil supply / discharge hole 65b It is preferable that a notch is formed on the entire circumference of the corner portion of the second piston portion 63a so that the oil can be easily supplied and discharged.

○ In the embodiment, the positions of the first stopper member 56a and the second stopper member 56b in the first steering angle limiting cylinder 51, and the second steering angle limiting cylinder 61 in the third stopper member 66a and the fourth stopper member 66b. The position within may be changed as appropriate.

○ In the embodiment, in the control device 20, even when the position of the accelerator lever 19 is held at the accelerator fully open position, the first rod portion 53b and the second rod portion 63b are inside the first steering angle changing cylinder 31. And, it is not necessary to control the operation of the switching valve 84 so that it protrudes into the second steering angle changing cylinder 41.

○ In the embodiment, the marine steering device 30 includes, for example, the hydraulic pressure and oil temperature in the first steering angle changing cylinder 31 and the second steering angle changing cylinder 41, in the first steering angle limiting cylinder 51, and in the first steering angle limiting cylinder 51. Various sensors for detecting the oil pressure and oil temperature in the second steering angle limiting cylinder 61, the rotation speed of the internal combustion engine 14, the acceleration of the ship 10, and the like may be further provided. Then, the control device 20 may control the operation of the switching valve 84 by using each parameter in addition to the ship speed. According to this, the operation of the switching valve 84 can be controlled with high accuracy.

○ In the embodiment, the control device 20 outputs a warning display to the display 24 so that the steering angle of the outboard motor propulsion unit 12 is equal to or less than the steering angle limit value α in step S27, but the present invention is not limited to this, for example. Warnings may be given by lamp, buzzer or voice.

○ In the embodiment, the marine steering device 30 may include a piston position detection sensor that detects the positions of the first steering angle limiting piston 53 and the second steering angle limiting piston 63, respectively. In this case, the control device 20 does not have to measure the movement time of the first piston portion 53a and the second piston portion 63a as the elapsed time for changing the steering angle.

○ In the embodiment, the maximum steering angle of the outboard motor propulsion unit 12 does not have to be ± 90 degrees, and the maximum steering angle is not particularly limited.
○ In the embodiment, the first steering angle changing tube 32 and the second steering angle changing tube 42 may be arranged in a state where their respective openings are connected. Further, the first steering angle changing tube 32 and the second steering angle changing tube 42 may be integrally formed by connecting their respective openings. That is, the steering angle changing cylinder may be formed of one cylinder. In short, the steering angle changing cylinder has a pair of cylinder chambers, and the pair of steering angle changing pistons may reciprocate in the steering angle changing cylinder by the hydraulic pressure in the pair of cylinder chambers. ..

○ In the embodiment, the first steering angle limiting cylinder 51 and the second steering angle limiting cylinder 61 are, for example, the first steering angle limiting piston 53 and the second steering angle limiting piston 53 by the return spring when switching from the restricted state to the allowable state. It may be a single-acting cylinder that moves each of the second steering angle limiting pistons 63.

10 ... Ship, 11 ... Hull, 12 ... Outer unit propulsion unit, 18 ... Handle, 19 ... Accelerator lever, 30 ... Ship steering device, 31 ... First steering angle changing cylinder constituting the steering angle changing cylinder, 33 ... First steering angle changing piston which is a steering angle changing piston, 34 ... First cylinder chamber as a cylinder chamber, 41 ... Second steering angle changing cylinder constituting a steering angle changing cylinder, 43 ... Steering angle The second steering angle changing piston which is a changing piston, 51 ... the first steering angle limiting cylinder which is a steering angle limiting cylinder, 53 ... the first steering angle limiting piston which is a steering angle limiting piston, 53a ... piston A first piston portion as a portion, 53b ... a first rod portion as a rod portion, 56a ... a first stopper member which is a stopper member, 56b ... a second stopper member which is a stopper member, 61 ... a cylinder for limiting a steering angle. 2nd steering angle limiting cylinder, 63 ... 2nd steering angle limiting piston which is a steering angle limiting piston, 63a ... first piston portion as a piston portion, 63b ... first rod portion as a rod portion, 66a ... stopper A third stopper member which is a member, 66b ... a fourth stopper member which is a stopper member, 71 ... a rack and pinion mechanism, 81 ... a first hydraulic pump, 83 ... a second hydraulic pump.

Claims (4)

A marine steering device that steers an outboard motor propulsion unit mounted on the outside of the hull.
A cylinder for changing the steering angle having a pair of cylinder chambers to which hydraulic oil is supplied from the first hydraulic pump according to the amount of operation of the steering wheel.
A pair of steering angle changing pistons that reciprocate in the steering angle changing cylinder by hydraulic pressure in the pair of cylinder chambers.
A rack and pinion mechanism that connects the pair of steering angle changing pistons and drives the pair of steering angle changing pistons to change the steering angle of the outboard motor propulsion unit.
A pair of steering angle limiting cylinders each having a steering angle limiting piston connected to the steering angle changing cylinder and reciprocating with hydraulic oil supplied via a second hydraulic pump are provided.
The steering angle limiting pistons are provided so as to project from the piston portion and the piston portion sliding in the steering angle limiting cylinder, and for changing the steering angle according to the reciprocating movement of the piston portion. Each of the cylinders has a rod portion that can appear and disappear in each of the cylinder chambers.
Each steering angle limiting piston is in an allowable state in which each rod portion is immersed in each cylinder chamber of the steering angle changing cylinder to allow movement of each steering angle changing piston to the stroke end. It is possible to switch between the regulated state in which the rod portion projects into the cylinder chamber of the steering angle changing cylinder to regulate the movement of the steering angle changing piston to the stroke end. ,
Each of the steering angle limiting pistons is, when the ship speed is equal to or higher than a predetermined steering angle limiting applicable ship speed, at least operated so as to be in the regulated state. .. The marine steering device according to claim 1, wherein each of the steering angle limiting cylinders is provided with a stopper member for limiting the stroke range of each steering angle limiting piston. Claim 1 or claim, wherein each of the steering angle limiting pistons operates so as to switch from the permissible state to the regulated state when the ship speed increases and becomes equal to or higher than the steering angle limiting applicable ship speed. Item 2. The marine steering device according to item 2. The first or second aspect of the invention, wherein each steering angle limiting piston operates so as to switch from the allowable state to the regulated state when the position of the accelerator lever is held at the accelerator fully open position. Marine steering system.