An engine-driven working machine including a controller by which a time period until the rotation speed limitation mode is canceled can be shortened. After a throttle valve is moved to a fully-closed position by an operation to allow the engine to finish the fast idling state and while the engine is transited to an idling state, the controller cancels the rotation speed limitation mode by detecting an event in which a cycle period of rotation speed variations of the engine is longer than a cycle period of rotation speed variation in the fast idling state.

A method controls an internal combustion engine having a drive output shaft that is coupled to an input shaft of a transmission. The internal combustion engine and the transmission are encompassed by a drivetrain for the drive of a motor vehicle. The method includes determining a rotational speed of the drive output shaft of the internal combustion engine and determining a rotational acceleration of the drive output shaft based on the rotational speed of the drive output shaft. A dynamic torque of the internal combustion engine is determined as a product of the rotational acceleration and a dynamic moment of inertia of the internal combustion engine. A maximum combustion torque of the internal combustion engine is determined from a sum of a predetermined maximum torque at the input shaft of the transmission and the dynamic load torque of the internal combustion engine.

The power equipment such as a lawn mower (10) comprises an internal combustion engine (100) having a plurality of cylinders, an engine control unit (110) for selectively deactivating at least one of the cylinders, a work implement such as a cutting blade (70) connected to the engine in a power transmitting relationship, a clutch (80) provided in a power transmission path between the engine and the work implement, and a central control unit (50) for controlling an operation of a propelling device, the clutch and the engine control unit. The central control unit is configured to start the engine with two or more of the cylinders activated, to cause the engine control unit to operate the engine at a prescribed rotational speed, and to cause the engine control unit to deactivate at least one of the cylinders when the engine has reached a stable state at the prescribed rotational speed.

A multipurpose vehicle includes an engine, a fuel supply unit that supplies fuel to the engine, a gear transmission device that changes speed of power from the engine through a shifting operation, a coupling state detection sensor that detects a coupling state of the gear transmission device, a determination unit that determines whether the coupling state is an incomplete coupling state based on a detection signal from the coupling state detection sensor, and a fuel supply control unit that executes a fuel cut to reduce a fuel supply amount of the fuel from the fuel supply unit to the engine to a value less than a reference value, if the determination unit determines that the coupling state is the incomplete coupling state.

Disclosed is a method for regulating the speed of an engine which drives a disengageable device. The regulation of the engine speed is effected in accordance with a first mode when the disengageable device is disengaged and in accordance with a second mode when the disengageable device is engaged. The determination is effected by: —estimating the resistive torque exerted on the engine by the disengageable device; —changing a binary value from a first value representative of the disengaged state to a second value representative of the engaged state when the estimated resistive torque is higher than a first predetermined threshold for a first predetermined period of time; and —changing the binary value from the second value to its first value when, for a second predetermined period of time, the estimated resistive torque is lower than a second threshold possibly equal to the first threshold.

A control system for operating a work vehicle powertrain includes an engine configured to generate power for an output shaft. The control system includes a transmission positioned operatively between the engine and the output shaft and configured to selectively transfer the power along a power flow path between the engine and the output shaft. The transmission includes an input shaft; at least one intermediate shaft; at least one directional clutch; and intermediate clutches configured for selective engagement to transfer power between the at least one intermediate shaft and the output shaft. A controller is configured to receive a vehicle stop request to stop the work vehicle; implement, upon receiving the vehicle stop request, a clutch braking function; and generate, upon the implementation of the clutch braking function, clutch commands to engage at least two of the intermediate clutches selected such that the output shaft is slowed and stopped.

An engine system is provided, which includes a supercharger driven by a crankshaft of an engine, an electromagnetic clutch disconnectably connecting the crankshaft to the supercharger, and a controller configured to output a control signal to the electromagnetic clutch. The controller includes a processor configured to execute an uphill-angle detecting module to detect an uphill angle during traveling of a vehicle, an uphill determining module to determine whether the detected uphill angle is above a given first uphill angle, and a boost controlling module to, when the detected uphill angle is above the first uphill angle, control the electromagnetic clutch to connect the crankshaft to the supercharger even when a target torque of the engine is within a not-boosting range.

An engine control device for a saddle riding vehicle includes a mechanical centrifugal clutch for connecting and disconnecting driving force from an engine to a driving wheel, a throttle operator to adjust output power of the engine, a motor to rotate a crankshaft of the engine, and a control unit to control the motor and a fuel injection system. The control unit executes injection stopping control for stopping fuel injection during deceleration of the vehicle and executes, when an opening operation of the throttle operator is performed after an engine speed becomes equal to or lower than a centrifugal clutch disconnection speed at which the centrifugal clutch is disconnected, acceleration assist control for rotating the crankshaft with the motor.

A hybrid vehicle for anti-rollover through active control of an engine and an anti-rollover control method for the same, may include detecting a roll angle of the vehicle, and when the detected roll angle is equal to or greater than a threshold roll angle, accelerating or decelerating, by a controller, the engine in a state in which the engine clutch is released depending on a direction of the roll angle.

A vehicle control device controls a vehicle including an internal combustion engine, an electric motor, a drive wheel, and a lock-up clutch provided in a power transmission path from the internal combustion engine and the electric motor to the drive wheel. The vehicle control device is configured to: not execute a motor vibration damping control and a slip vibration damping control in a non-vibration damping region; execute the motor vibration damping control and the slip vibration damping control in a first vibration damping region in a high load state or a low rotation speed state; and execute the motor vibration damping control and not execute the slip vibration damping control in a second vibration damping region in a medium load state or a medium rotation speed state.