A pre-engaged piston starter system of an automobile vehicle includes an engine having a flywheel to start the engine connected to the engine by an engine shaft. A starter motor provides rotational energy to a starter gear. A pinion gear transfers rotational energy of the starter gear to the flywheel. A solenoid is energized to shift the pinion gear to an engaged position between the flywheel and the starter gear. An auto-stop mode is entered when an engine speed is decreased below a calibrated threshold speed defining approximately 250 rpm. A calculated pinion pre-engagement engine speed allows engagement of the pinion gear when the engine speed is below the calibrated threshold speed.

An engine start control device includes an pass determination section that performs a pass determination process of determining, based on a rotation state of the engine output shaft, whether a piston in a cylinder of the engine can pass over a compression top dead center for a rotation drop period in response to an occurrence of the start request. The engine start control device also includes a start control section that when it is determined that the piston cannot pass over the compression top dead center, starts driving of the motor in a low reaction force period to start the engine, the low reaction force period being a period in which a reaction force applied to the piston by a cylinder internal pressure in the cylinder is a predetermined value or less.

There is provided an engine starting device, including: a motor generator coupled to a crankshaft of an engine; and a starter including a pinion provided in a detachable manner from a ring gear provided on the crankshaft, and configured to mesh with the ring gear when the engine is started, wherein the engine is cranked through simultaneous cranking by both of the motor generator and the starter when a condition set in advance is satisfied, and wherein, in the simultaneous cranking, the starter starts rotating after the motor generator starts rotating.

Systems and methods for operating a vehicle that includes a starter motor are described. In one example, the starter motor may engage a flywheel of an engine and rotate the engine without starting the engine in response to a request to move the vehicle without starting the engine. The starter motor may provide the propulsive force to move the vehicle a short distance.

An internal-combustion engine includes a belt-driven starter generator and makes an idling stop while a vehicle is at a stop. In the process of the engine revolution speed decreasing with cutting of fuel to stop the vehicle, to suppress the reduction in restart responsiveness caused by slack in a belt, preliminary powering of the starter generator is performed. The belt tension during deceleration microscopically changes periodically between a relatively high-tension period and a relatively low-tension period due to pulsation of the engine revolution speed. Slack in the belt does not occur in the high tension period, and thus preliminary powering torque is applied only in the low-tension period.

An electric starter system is disclosed for use with an engine having a flywheel. The electric starter system includes a pinion gear and a solenoid device coupled to the pinion gear. The solenoid device is movable between a pre-engaged position when the pinion gear is moved into engagement with the flywheel and a disengaged position when the pinion gear is disengaged from the flywheel. A brushless starter motor is selectively connectable to the flywheel of the engine via the pinion gear during a requested engine start event. A latch mechanism is selectively engageable with the solenoid device. The latch mechanism is moveable between a latched position in which the solenoid device is mechanically held in the pre-engaged position and an unlatched position in which the solenoid device is released for movement to the disengaged position.

An electric starter system is disclosed for use with an engine having a flywheel. The electric starter system includes a pinion gear and a solenoid device coupled to the pinion gear. The solenoid device is movable between a pre-engaged position when the pinion gear is moved into engagement with the flywheel and a disengaged position when the pinion gear is disengaged from the flywheel. A brushless starter motor is selectively connectable to the flywheel of the engine via the pinion gear during a requested engine start event. A latch mechanism is selectively engageable with the solenoid device. The latch mechanism is moveable between a latched position in which the solenoid device is mechanically held in the pre-engaged position and an unlatched position in which the solenoid device is released for movement to the disengaged position.

A control apparatus controls the operation of a starter such that, after an idling stop is executed and before a request for starting an engine is subsequently issued, the control apparatus executes a preset which causes a pinion to engage a ring gear. A control apparatus controls the operation of a starter such that, after an idling stop is executed and before a request for starting an engine is subsequently issued, the control apparatus executes a preset which causes a pinion to engage a ring gear. It is determined that the preset condition has been cancelled, and the preset is again executed. In that case, the pinion is already engaged with the ring gear at the time point when a request for starting the engine is issued. In that way it is unnecessary for the control apparatus to push out the pinion after a start request is issued.

Methods and systems are provided for dealing with a change of mind event during an automatic shut-down of an engine in which the speed at which a starter motor used to restart the engine is disengaged is based upon the comparison of current engine speed (N) with a cranking speed limit (S.sub.LIM). In one example, during an engine restart while the engine is spinning down, the starter motor may crank the engine to a threshold cranking engine speed adjusted based on a position of the gear.

An internal-combustion engine includes a belt-driven starter generator and makes an idling stop while a vehicle is at a stop. In the process of the engine revolution speed decreasing with cutting of fuel to stop the vehicle, to suppress the reduction in restart responsiveness caused by slack in a belt, preliminary powering of the starter generator is performed. The belt tension during deceleration microscopically changes periodically between a relatively high-tension period and a relatively low-tension period due to pulsation of the engine revolution speed. Slack in the belt does not occur in the high tension period, and thus preliminary powering torque is applied only in the low-tension period.