Engine control for watercraft

• US 6,709,302 B2
• Filed: 02/15/2002
• Issued: 03/23/2004
• Est. Priority Date: 02/15/2001
• Status: Expired due to Term

• Current Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Original Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Inventors: Yanagihara, Tsuide
• Primary Examiner(s): BASINGER, SHERMAN D
• Application Number:
  US10/080,371
• Publication Number:
  US 20030013354A1
• Time in Patent Office: 767 Days
• Field of Search: 440/1, 440/84, 440/87, 123/377
• US Class Current: 440/1
• CPC Class Codes: B63B 34/10 Power-driven personal watercraft, e.g. water scooters water jet propulsion B63H11/00; jet steering B63H25/46; Accessories therefor
• CPC Class Codes: B63H 21/21 Control means for engine or transmission, specially adapted for use on marine vessels
• CPC Class Codes: B63H 21/22 the propulsion power units being controlled from exterior of engine room, e.g. from navigation bridge; Arrangements of order telegraphs
• CPC Class Codes: B63H 21/24 the vessels being small craft, e.g. racing boats
• CPC Class Codes: F02B 61/045 for marine engines
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 2011/103 at least one throttle being alternatively mechanically linked to the pedal or moved by an electric actuator
• CPC Class Codes: F02D 41/061 the corrections being time dependent
• CPC Class Codes: F05C 2201/021 Aluminium

Abstract

A watercraft includes an improved engine control system that enhances the responsiveness of the watercraft and eases watercraft operation. The watercraft includes a propulsion device, such as a jet propulsion unit, and an engine that powers the propulsion device. The engine control system is configured to maintain or increase engine speed under certain operating conditions.

Claims

1. A jet propelled watercraft comprising:

an engine having at least one throttle valve, the throttle valve being movable between an idle position and a fully open position;

a throttle operator remotely positioned relative to the engine and coupled to the throttle valve, the throttle operator being movable between first and second positions whereby the throttle operator causes the throttle valve to move between the idle and fully open positions, respectively; and

an engine control system comprising a first sensor configured to detect an operating state of the watercraft or the engine, a second sensor configured to detect a position of the throttle operator, a throttle valve control mechanism including an actuator cooperating with the throttle valve under at least one operating state of the watercraft or the engine, and a controller communicating with the first and second sensors and with the throttle valve control mechanism, the controller being configured to activate the throttle valve control mechanism once the operating state of the watercraft or engine is greater than a predetermined state for a preset period of time and to leave active the throttle valve control mechanism at least when the throttle operator quickly moves to the first position so as to maintain the throttle valve between the idle and fully open positions.

2. The watercraft of claim 1, wherein the throttle operator is coupled to the throttle valve by a throttle drive mechanism, and the actuator is coupled to the throttle valve independently of the throttle drive mechanism.

3. The watercraft of claim 2, wherein the throttle drive mechanism comprises a throttle pulley.

4. The watercraft of claim 3, wherein the throttle drive mechanism additionally comprises a cable linking the throttle operator to the throttle pulley and a biasing member arranged to bias the throttle operator towards the first position.

5. The watercraft of claim 1, wherein the first sensor is an engine speed sensor configured to output a signal to the controller that is indicative of engine rotational speed.

6. The watercraft of claim 1, wherein the first sensor is a watercraft speed sensor configured to output a signal to the controller that is indicative of a vehicle speed of the watercraft.

7. The watercrafi of claim 1, wherein the first sensor is a throttle valve position sensor configured to output a signal to the controller that is indicative of the position of the throttle valve.

8. The watercraft of claim 1, wherein throttle valve control mechanism is configured to maintain the throttle valve open to a degree corresponding to a trolling condition of the watercraft.

9. The watercraft of claim 1, wherein throttle valve control mechanism is configured to maintain the throttle valve open to a degree corresponding to a transient condition of the watercraft between a displacement mode of operation and a planing mode of operation.

10. The watercraft of claim 1, wherein the engine control system additionally comprises a steering angle sensor, and wherein the controller is configured to deactivate the throttle valve control mechanism so as to permit the throttle valve to return to an idle position when a steering angle is less than a preset degree.

11. The watercraft of claim 1, wherein the controller and the throttle valve control mechanism are configured to maintain the throttle valve at a preset position between the idle and fully open positions.

12. The watercraft of claim 1, wherein the controller and the throttle valve control mechanism are configured to retard movement of the throttle valve from a preset position, which lies between the idle and fully open positions, to the idle position.

13. The watercraft of claim 12, wherein the controller and the throttle valve control mechanism are configured to gradually decrease the opening degree of the throttle valve at least over a range of movement between the preset position and the idle position.

14. A jet propelled watercraft comprising:

an engine having at least one throttle valve, the throttle valve being movable between a closed position and a fully open position;

a throttle operator remotely positioned relative to the engine and coupled to the throttle valve, the throttle operator being movable between first and second positions whereby the throttle operator causes the throttle valve to move between the closed and fully open positions, respectively;

a steering mast comprising a handlebar rotatably carried by the steering mast and configured to steer the watercraft; and

an engine control system comprising a first sensor configured to detect an operating state of the watercraft or the engine, a second sensor configured to detect a position of the throttle operator, a third sensor configured to detect an angular orientation of the handlebar, a throttle valve control mechanism including an actuator cooperating with the throttle valve under at least one operating state of the watercraft or the engine, and a controller communicating with the first and second sensors and with the throttle valve control mechanism, the controller being configured to activate the throttle valve control mechanism once the operating state of the watercraft or engine is greater than a predetermined state, and the controller and throttle valve control mechanism further being configured to delay closure of the throttle valve at least when the throttle operator moves to the first position and the handlebar exceeds a predetermined angular orientation, wherein the first sensor is an engine speed sensor configured to output a signal to the controller that is indicative of engine rotational speed.

15. A jet propelled watercraft comprising:

an engine having at least one throttle valve, the throttle valve being movable between a closed position and a fully open position;

a throttle operator remotely positioned relative to the engine and coupled to the throttle valve, the throttle operator being movable between first and second positions whereby the throttle operator causes the throttle valve to move between the closed and fully open positions, respectively;

a steering mast comprising a handlebar rotatably carried by the steering mast and configured to steer the watercraft; and

an engine control system comprising a first sensor configured to detect an operating state of the watercraft or the engine, a second sensor configured to detect a position of the throttle operator, a third sensor configured to detect an angular orientation of the handlebar, a throttle valve control mechanism including an actuator cooperating with the throttle valve under at least one operating state of the watercraft or the engine, and a controller communicating with the first and second sensors and with the throttle valve control mechanism, the controller being configured to activate the throttle valve control mechanism once the operating state of the watercraft or engine is greater than a predetermined state, and the controller and throttle valve control mechanism further being configured to delay closure of the throttle valve at least when the throttle operator moves to the first position and the handlebar exceeds a predetermined angular orientation, wherein the controller is configured to activate the throttle valve control mechanism once the operating state of the watercraft or engine is greater than a predetermined state for a preset period of time.

16. The watercraft according to claim 1, wherein the controller is configured to prevent actuation of the throttle valve control mechanism until the operating state of the watercraft or engine is greater than a predetermined state for the preset period of time.