Engine output control system for water jet propulsion boat

• US 7,364,480 B2
• Filed: 06/29/2005
• Issued: 04/29/2008
• Est. Priority Date: 06/29/2004
• Status: Expired due to Fees

• Current Assignee: Yamaha Marine Kabushiki Kaisha
• Original Assignee: Yamaha Marine Kabushiki Kaisha
• Inventors: Ito, Kazumasa, Kinoshita, Yoshimasa
• Primary Examiner(s): Olson; Lars A.
• Assistant Examiner(s): Venne; Daniel V.
• Application Number:
  US11/169,374
• Publication Number:
  US 20050287886A1
• Time in Patent Office: 1,035 Days
• Field of Search: 440/1, 440/38, 440 40- 43, 440/84, 440/87, 114/144.R, 114/144.RE, 114/144.E, 701/21
• 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 11/08 of rotary type
• CPC Class Codes: B63H 21/14 relating to internal-combustion engines of outboard type B63H20/00
• CPC Class Codes: B63H 25/02 Initiating means for steering , for slowing down, otherwise than by use of propulsive elements, or for dynamic anchoring
• CPC Class Codes: B63H 25/46 Steering or dynamic anchoring by jets or by rudders carrying jets steering or dynamic anchoring by deflecting or directing main propulsion jets B63H11/00
• CPC Class Codes: F02D 11/02 characterised by hand, foot, or like operator controlled initiation means
• CPC Class Codes: F02D 41/021 Introducing corrections for particular conditions exterior to the engine conjoint control of vehicle sub-units for propelling the vehicle B60W30/18
• CPC Class Codes: F02D 41/12 for deceleration F02D41/0005, F02D41/107 take precedence
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F02D 9/02 concerning induction conduits throttle valves, or arrangements thereof in conduits F02D9/08

Abstract

A jet-propelled watercraft can include an engine output control system that adjusts the output of the engine based on a steering force and the engine speed. The control system can also be configured to detect abnormalities in the steering force sensor and to prohibit the increase engine output control when an abnormality is detected.

Claims

1. An engine output control system for a watercraft configured to be propelled by an engine-driven jet propulsion unit configured to eject water from a nozzle, the control system comprising a steering force detecting means for detecting a steering force applied by an operator, a decelerating state determining means for determining if the watercraft is in a predetermined decelerating state, a decelerating engine output control means for controlling decelerating engine output based on the steering force detected by the steering force detecting means, when the decelerating state determining means determines that the watercraft is in the predetermined decelerating state, and a decelerating engine output control prohibiting means for prohibiting the decelerating engine output control means from decelerating engine output control when the steering force detected by the steering force detecting means falls within a normal range between a maximum threshold and minimum threshold, and variation in steering force detected by the steering force detecting means within a predetermined time period is equal to or lower than a given predetermined value.

2. The engine output control system for a watercraft according to claim 1, wherein the decelerating engine output control prohibiting means prohibits the decelerating engine output control means from decelerating engine output control, when the steering force detected by the steering force detecting means falls xxithin a normal range between the maximum threshold and minimum threshold, and variation in steering force detected by the steering force detecting means within the predetermined time period has been maintained equal to or lower than the given predetermined value for a given predetermined time period different from the aforementioned predetermined time period.

3. The engine output control system for a watercraft according to claim 1, wherein the decelerating engine output control prohibiting means prohibits the decelerating engine output control means from decelerating engine output control, when the steering force detected by the steering force detecting means is equal to or greater than a second maximum threshold, that is equal to or greater than the maximum threshold, or equal to or lower than a second minimum threshold, that is equal to or lower than the minimum threshold.

4. The engine output control system for a watercraft according to claim 2, wherein the decelerating engine output control prohibiting means prohibits the decelerating engine output control means from decelerating engine output control, when the steering force detected by the steering force detecting means is equal to or greater than a second maximum threshold, that is equal to or greater than the maximum threshold, or equal to or lower than a second minimum threshold, that is equal to or lower than the minimum threshold.

5. The engine output control system for a watercraft according to claim 1, wherein the decelerating engine output control prohibiting means comprises an informing means for informing an operator that the decelerating engine output control has been prohibited.

6. The engine output control system for a watercraft according to claim 2, wherein the decelerating engine output control prohibiting means comprises an informing means for informing an operator that the decelerating engine output control has been prohibited.

7. The engine output control system for a watercraft according to claim 3, wherein the decelerating engine output control prohibiting means comprises an informing means for informing an operator that the decelerating engine output control has been prohibited.

8. The engine output control system for a watercraft according to claim 4, wherein the decelerating engine output control prohibiting means comprises an informing means for informing an operator that the decelerating engine output control has been prohibited.

9. An engine output control system for a watercraft configured to be propelled by an engine-driven jet propulsion unit configured to eject water from a nozzle and including a steering member, the control system comprising a steering force sensor configured to detect a steering force applied to the steering member by an operator, a decelerating state determining module configured to determine if the watercraft is in a predetermined decelerating state, a decelerating engine output control module configured to control the engine output based on the steering force detected by the steering force sensor, when the decelerating state determining module determines that the watercraft is in the predetermined decelerating state, and a decelerating engine output control prohibiting module configured to prohibit the decelerating engine output control module from decelerating engine output control when the output from the steering force sensor falls within a normal range between a maximum threshold and minimum threshold, and variation in steering force detected by the steering force sensor within a predetermined time period is equal to or lower than a given predetermined value.

10. The engine output control system for a watercraft according to claim 9, wherein the decelerating engine output control prohibiting module is configured to prohibit the decelerating engine output control module from decelerating engine output control, when the steering force detected by the steering force sensor falls within a normal range between the maximum threshold and minimum threshold, and variation in steering force detected by the steering force sensor within the predetermined time period has been maintained equal to or lower than the given predetermined value for a given predetermined time period different from the aforementioned predetermined time period.

11. The engine output control system for a watercraft according to claim 9, wherein the decelerating engine output control prohibiting module is configured to prohibit the decelerating engine output control module from decelerating engine output control, when the steering force detected by the steering force sensor is equal to or greater than a second maximum threshold, that is equal to or greater than the maximum threshold, or equal to or lower than a second minimum threshold, that is equal to or lower than the minimum threshold.

12. The engine output control system for a watercraft according to claim 10, wherein the decelerating engine output control prohibiting module is configured to prohibit the decelerating engine output control module from decelerating engine output control, when the steering force detected by the steering force sensor is equal to or greater than a second maximum threshold, that is equal to or greater than the maximum threshold, or equal to or lower than a second minimum threshold, that is equal to or lower than the minimum threshold.

13. The engine output control system for a watercraft according to claim 9, wherein the decelerating engine output control module comprises an informing device configured to notify an operator that the decelerating engine output control has been prohibited.

14. The engine output control system for a watercraft according to claim 10, wherein the decelerating engine output control module comprises an informing device configured to notify an operator that the decelerating engine output control has been prohibited.

15. The engine output control system for a watercraft according to claim 11, wherein the decelerating engine output control module comprises an informing device configured to notify an operator that the decelerating engine output control has been prohibited.

16. The engine output control system for a watercraft according to claim 12, wherein the decelerating engine output control module comprises an informing device configured to notify an operator that the decelerating engine output control has been prohibited.