Steering system for small boat

• US 20070066154A1
• Filed: 09/05/2006
• Published: 03/22/2007
• Est. Priority Date: 09/02/2005
• Status: Active Grant

• Current Assignee: Yamaha Marine Kabushiki Kaisha
• Original Assignee: Yamaha Marine Kabushiki Kaisha
• Inventors: Mizutani, Makoto
• Granted Patent: US 7,422,496 B2
• Time in Patent Office: Days
• US Class Current: 440/1
• CPC Class Codes: B63B 79/10 using sensors, e.g. pressure sensors, strain gauges or accelerometers
• CPC Class Codes: B63B 79/40 for controlling the operation of vessels, e.g. monitoring their speed, routing or maintenance schedules
• CPC Class Codes: B63H 20/12 Means enabling steering
• CPC Class Codes: B63H 21/213 Levers or the like for controlling the engine or the transmission, e.g. single hand control levers

Abstract

A steering system for a small boat can include an outboard motor mounted to a hull, a steering wheel operated by a boat operator for steering the boat, a steering angle sensor for detecting a steering angle of the steering wheel, a steering device for moving the outboard motor relative to the hull in response to the steering angle of the steering wheel, and a controller for determining a target steering angle to be achieved by the steering device using the steering angle and steering characteristics. The steering characteristics are determined in response to running conditions.

Claims

1. A steering system for a small boat comprising a propulsion unit mounted to a hull, a steering wheel operated by a boat operator for steering the boat, a steering angle sensor configured to detect a steering angle of the steering wheel, a steering device configured to move the propulsion unit relative to the hull in response to the steering angle of the steering wheel, and a controller configured to determine a target steering angle to be achieved by the steering device using the steering angle of the steering wheel and steering characteristics, wherein the steering characteristics are determined in response to running conditions.

2. The steering system for a small boat according to claim 1, wherein the running conditions comprise at least speed and an acceleration or deceleration state.

3. The steering system for a small boat according to claim 2, wherein the acceleration or deceleration state is detected using a throttle opening or the amount of accelerator displacement.

4. The steering system for a small boat according to claim 2, wherein the acceleration or deceleration state is detected using a steering unit load to the steering device.

5. The steering system for a small boat according to claim 2, wherein the acceleration or deceleration state is detected using a change in speed with time.

6. The steering system for a small boat according to claim 2, wherein the steering characteristics are determined such that a change in target steering angle to the speed becomes smaller for higher speed.

7. A steering system for a small boat comprising a propulsion unit mounted to a hull, a steering wheel operated by a boat operator for steering the boat, a steering angle sensor configured to detect a steering angle of the steering wheel, a steering device configured to move the propulsion unit relative to the hull in response to the steering angle of the steering wheel, and means for determining a target steering angle to be achieved by the steering device using the steering angle of the steering wheel and steering characteristics, wherein the steering characteristics are determined in response to running conditions.

8. A steering system for a boat comprising a steering unit mounted to a hull, a steering input device configured to be manipulable by a boat operator to allow the boat operator to input steering commands into the steering input device, a steering input sensor configured to detect steering commands input into the steering input device, a steering device configured to move the steering unit relative to the hull, and a controller configured to determine a target steering angle for the steering device using the detected state of the steering input device, a speed of the boat, and data indicative of acceleration of the boat.

9. The steering system according to claim 8, wherein the controller is configured to determine the target steering angle in accordance with at least a first relationship between steering input commands and target steering angle for lower boat speeds and a second relationship between steering input commands and target steering angle for higher boat speeds.

10. The steering system according to claim 8, wherein the controller is configured to delay the transition between the first and second relationships based on the acceleration of the boat.

11. The steering system according to claim 8, wherein the controller is configured to change the determination of the target steering angle from the first relationship to the second relationship at a threshold boat speed, and to change the threshold boat speed depending on the acceleration of the boat.

12. The steering system according to claim 8, wherein the controller determines the acceleration of the boat based on at least one of a throttle valve position, a throttle lever of the boat, a load on the steering unit, and a change in boat speed.