The embodiments described herein include systems with a variable reluctance sensor (VRS) interface and methods of their operation. Embodiments of VRS interfaces include a clearing signal generator configured to generate a clearing signal corresponding with the timing of a noise event. The clearing signal may be configured to clear a post-processing circuit.

An ignition control apparatus, e.g., for an internal combustion engine, includes a rotational speed calculation unit that calculates a rotational speed of an alternating current generator. A rotor of the alternating current generator is driven to rotate in synchronization with reciprocating motion of a piston of the internal combustion engine. An ignition timing determination unit determines an ignition timing of the internal combustion engine based on the rotational speed calculated by the rotational speed calculation unit. An ignition control unit supplies electric power to an ignition coil such that the internal combustion engine is ignited at the timing determined by the ignition timing determination unit.

Provided is a crank angle detection device that includes an ACG rotor supported by an end of a crank shaft and configured to rotate integrally with the crank shaft, a metal-plate-made pulsar ring including a ring-shaped plate portion and a detected portion that includes a plurality of convex portions formed at an outer circumference of the ring-shaped plate portion, and being configured to rotate integrally with the ACG rotor with the ring-shaped plate portion fixed to the ACG rotor, and a magnetic sensor arranged at an outer circumference of the pulsar ring and configured to detect the detected portion. Such a crank angle detection device is capable of detecting a crank angle with high accuracy.

An ignition control apparatus, e.g., for an internal combustion engine, includes a rotational speed calculation unit that calculates a rotational speed of an alternating current generator. A rotor of the alternating current generator is driven to rotate in synchronization with reciprocating motion of a piston of the internal combustion engine. An ignition timing determination unit determines an ignition timing of the internal combustion engine based on the rotational speed calculated by the rotational speed calculation unit. An ignition control unit supplies electric power to an ignition coil such that the internal combustion engine is ignited at the timing determined by the ignition timing determination unit.

It has been found that high density articles having improved strength, corrosion resistance, better durability, and decent magnetic characteristics can be manufactured from a ferritic stainless steel powder using a novel method. This technique is especially beneficial in manufacturing parts, such as, reluctor rings, tone wheels, trigger wheels, pump impeller blades, and EGR valves, in large quantities. This method involves (1) compacting the ferritic stainless steel powder in a mold into a green article, (2) sintering the green article at an elevated temperature under vacuum or a reducing atmosphere to produce a sintered article, and (3) forging the sintered article under a reducing or an inert gas atmosphere to a density of greater than 7.5 g/cc in the presence of a graphite free lubricant to produce the high density article.

Provided is a crank angle detection device that includes an ACG rotor supported by an end of a crank shaft and configured to rotate integrally with the crank shaft, a metal-plate-made pulsar ring including a ring-shaped plate portion and a detected portion that includes a plurality of convex portions formed at an outer circumference of the ring-shaped plate portion, and being configured to rotate integrally with the ACG rotor with the ring-shaped plate portion fixed to the ACG rotor, and a magnetic sensor arranged at an outer circumference of the pulsar ring and configured to detect the detected portion. Such a crank angle detection device is capable of detecting a crank angle with high accuracy.

A system and method for enhancing spark generation in an ignition coil of an internal combustion engine at low rotational speeds of the flywheel. The method and system monitor the rotational speed of the flywheel and, when the rotational speed of the flywheel is below a threshold rotational speed, the system and method supplies voltage pulses to the primary winding. The timing of the voltage pulses supplied to the primary winding are triggered off of voltage transitions in pulses induced in the primary winding upon rotation of the flywheel. Once the internal combustion engine has started, the switching device transitions into a second condition to disconnect the electrical storage device from the primary winding. The spark generation system of the present disclosure allows for starting of an internal combustion engine upon slower rope pull starting or upon discharge of a starter battery.

An engine trigger wheel is disclosed having a central annular portion and a cylindrical rim portion defining a number of trigger teeth, wherein the central annular and cylindrical rim portions are pressed from a single piece of metal. A number of balance apertures are formed in the central annular portion to move a center of mass of the trigger wheel away from an axis of rotation. The engine trigger wheel when fastened to one end of a crankshaft of an engine provides both an indication of the angular position of the crankshaft and a counterweight function.

A method for determining the angular position of an engine by a crankshaft sensor and a camshaft sensor. The method includes production by the crankshaft sensor of a revolution event, determination of the angular position of the camshaft by identifying the start-of-tooth and end-of-tooth events following the revolution event, in rapid mode, over at most one revolution of the crankshaft, if a no tooth event occurs after the revolution event and if the determination of the angular position of the camshaft fails, the method continues with a step of determining the angular position of the camshaft by identification, in slow mode, over at least two crankshaft revolutions.

The application discloses a control device and a control method for an engine. The control device includes an electronic control unit configured to execute a stop-and-start control of automatically stopping the engine when a predetermined automatic stop condition is established and automatically restarting the engine when a predetermined automatic-restart condition is established during the automatic stop of the engine, and in a case where the automatic-restart condition is established during fuel cut-off according to the automatic stop of the engine, prohibit detection of the toothless part based on the pulse signal output from the crank angle sensor, for a period until the crankshaft is rotated by a predetermined crank angle or more after the automatic-restart condition is established.