Shift assist system for an outboard motor
AssigneeYamaha Marine Kabushiki Kaisha
InventorsMasaru Suzuki, Sadato Yoshida
Life of this patent
Estimating the term…
Abstract
A shift assist system for an outboard motor regulates the torque of the engine to ensure proper effortless shifting. The system recognizes open circuit or short circuit faults and nevertheless enables the torque of the engine to be reduced to facilitate easy gear selection.
Claims19
A system for assisting shifting of a fuel injected marine engine that recognizes an open circuit or short circuit faults and automatically reduces the engine speed comprising:
- a shift force detection unit including a switch responsive to an excessive force applied to a shift lever that is involved with shifting the marine engine,
- an electronic control unit coupled to the engine to control the timing and duration of the fuel injection cycle of said engine and the ignition timing of said engine,
- a current detector within said electronic control unit for detecting an amount of current from said shift force detection unit and automatically reducing the engine RPM when said amount of current is greater than or less than a value of N,
- said shift force detection unit including a current generator comprising a resistor in parallel with said switch, an amount of current of value N being produced when the battery voltage is across the resistor and the switch is open, an amount of current greater than N being produced when the switch closed, an amount of current greater than N being produced when the switch is abnormally short circuited, and an amount of current less than N being produced when the shift detection unit has an open circuit or is disconnected from the electronic control unit.
A system for assisting shifting of a fuel injected engine, the system comprising:
- a shift force detection unit including a switch responsive to an excessive force applied to a shift lever that is involved with shifting the engine,
- an electronic control unit coupled to the engine to control at least one of the timing and duration of the fuel injection cycle of said engine and the ignition timing of said engine,
- a current detector within said electronic control unit for detecting an amount of current from said shift force detection unit and automatically reducing the engine RPM when the said current is greater than or less than a value of N,
- said shift force detection unit including a current generator comprising a resistor in parallel with said switch, an amount of current of value N being produced when the battery voltage is across the resistor and the switch is open, an amount of current greater than N being produced when the switch closed, and an amount of current greater than N being produced when the switch is abnormally short circuited.
A system for assisting shifting of an engine, the system comprising:
- a shift force detection unit including a switch responsive to an excessive force applied to a shift lever that is involved with shifting the engine,
- an electronic control unit coupled to the engine to control the engine output power,
- a current detector within said electronic control unit for detecting an amount of current from said shift force detection unit and automatically reducing the engine output power when said amount of current is greater than or less than a value of N,
- said shift force detection unit including a current generator comprising a resistor in parallel with said switch, an amount of current of value N being produced when the battery voltage is across the resistor and the switch is open, an amount of current greater than N being produced when the switch closed, an amount of current greater than N being produced when the switch is abnormally short circuited, and an amount of current less than N being produced when the shift detection unit has an open circuit or is disconnected from the electronic control unit.
A system for assisting shifting through a shift lever of an engine, the system comprising:
- a shift force detection unit including a switch responsive to an excessive force applied to the shift lever,
- an electronic control unit coupled to the engine to control the engine output power,
- a current detector within said electronic control unit for detecting an amount of current from said shift force detection unit, said electronic control unit automatically reducing the engine output power when said amount of current is greater than or less than a value of N,
- said shift force detection unit including a current generator comprising a resistor in parallel with said switch, an amount of current of value N being produced when the battery voltage is across the resistor and the switch is open, an amount of current greater than N being produced when the switch closed, an amount of current greater than N being produced when the switch is abnormally short circuited, an amount of current less than N being produced when the shift detection unit has an open circuit or is disconnected, and an amount of current less than N being produced when the battery voltage falls below a predetermined value.
An outboard motor having a transmission unit, an electronic control unit, and a shift assist arrangement, said motor including an internal combustion engine having an engine block, a crankshaft, and a driveshaft communicating with the transmission unit, a shift assist control system including a force detecting unit comprising a shift force detecting switch and a parallel resistor circuit.
A method of assisting shifting of an engine having an electronic control unit which is not adversely affected by electrical short circuit or an electrical disconnect of a shift force detection unit comprising:
- supplying a normal amount of current N to the electronic control unit,
- detecting when the amount of current exceeds or is less than the amount of current N by a predetermined amount of current, and
- automatically reducing the engine RPM when the amount of current exceeds or is less than the amount of current N by the predetermined amount of current.
Dependencies are inferred from the claim text.