In some aspects, a spark plug includes a spark gap in an enclosure of the spark plug. The spark plug includes a passage in the interior of the enclosure. During operation of the engine, the passage directs flow through the spark gap, primarily away from a combustion chamber end of the enclosure. The passage can direct flow at a velocity of 5 meters/second or greater.

In accordance with one embodiment, an ignition coil assembly includes an ignition coil cover, a boot, and an ignition coil. The ignition coil cover includes a plurality of fins, an opening, and a channel. The boot includes a slotted opening and a centralized orifice and is configured to be disposed within the opening of the ignition coil cover. The ignition coil includes a seat and a tab. The ignition coil is configured to be disposed within the centralized orifice. The seat is capable of supporting the ignition coil within the centralized orifice of the boot. The tab is configured to be inserted into the slotted opening and the channel when the ignition coil is disposed within the centralized office and the boot is disposed within the opening.

A piston for a premixed spark-ignited or premixed dual fuel internal combustion engine is disclosed. The piston may be configured to reciprocate along a longitudinal axis of a combustion chamber defined by a cylinder of the engine. The piston may comprise a piston head, a top annular groove configured to receive a top annular ring, and a skirt having a pin bore extending along a pin bore axis that is configured to receive a wrist pin for connecting the piston to a connecting rod. The piston may further comprise a top land formed in the piston head that is chamfered in a direction perpendicular to the pin bore axis such that the top land does not contact an inner wall of the cylinder when the piston rocks about the pin bore axis. The top land may be non-chamfered in a direction parallel to the pin bore axis.

An ignition system includes an ignition coil with a primary winding and a secondary winding having a terminal for providing a high voltage (HV). An electrode arrangement of an igniter includes first and second HV electrodes coupled to the terminal of the secondary winding. The igniter also has at least one ground electrode. A first spark gap is defined between the first HV electrode and the at least one ground electrode, and a second spark gap is defined between the second HV electrode and the at least one ground electrode. A first capacitor is disposed in-line between the first HV electrode and the terminal of the secondary winding and a second capacitor disposed in-line between the second HV electrode and the terminal of the secondary winding of the ignition coil. The ignition system includes a driver module coupled to a terminal of the primary winding, for driving the ignition coil.

A hand-guided power tool is provided with an internal combustion engine that has a cylinder and a piston disposed in the cylinder and delimiting together with the cylinder a combustion chamber. A connecting rod connects the piston and the crankshaft. The piston in operation of the internal combustion engine rotatably drives the crankshaft. An electronic control unit and an ignition device with a spark plug are provided. A support is fixedly connected to the crankshaft and a signal transducer is fixedly connected to the support. The ignition device, utilizing a signal generated by the at least one signal transducer, fires the spark plug at a timing which is predetermined by the electronic control unit. The support has a polygonal conical receptacle and the crankshaft has a corresponding polygonal conical section arranged in the polygonal conical receptacle to fixedly connect the support and the crankshaft to each other.

A method for controlling starting of a Liquefied Petroleum Injection (LPI) engine of a mild hybrid electric vehicle includes driving a fuel pump when a first node of an ignition switch is selected, performing an engine cranking operation by driving a Mild Hybrid Starter & Generator (MHSG) when a second node of the ignition switch is selected, determining whether a cranking completion condition is satisfied while performing the engine cranking operation, comparing a pressure of a Liquefied Petroleum Gas (LPG) fuel with a target pressure, and controlling the MHSG to generate a torque corresponding to an idle torque of the LPI engine when the pressure of the LPG fuel is less than the target pressure.

A spark plug for a prechamber internal combustion engine, having: a body with a passage and a front end; a center electrode located in the passage and that projects past the front end; an insulator that surrounds a section of the center electrode and has a tapering front end that together with the passage forms a free annular space within the body; a ground electrode with an annular ignition section that surrounds a section of the center electrode located outside the body, forming a spark gap; the ground electrode has a mounting section connected to the front end of the body, and at least two web sections connecting the ignition section to the mounting section; located between the web sections are scavenging ports through which the annular space is in connection with the environment outside the spark plug.

A method for controlling the operation of an ignition exciter with a rechargeable energy source supplying electricity to a solid-state switch is disclosed. The method includes charging the energy source at a first rate when the voltage of the energy source is less than a first voltage reference value.

A pre-chamber spark plug that includes a shell. Additionally, the pre-chamber spark plug includes an insulator disposed within the shell. In a particular embodiment, a center electrode has a first portion surrounded by the insulator, and a second portion that extends from the insulator into a pre-chamber. The pre-chamber defined by the shell. In a further embodiment, a ground electrode is attached to the insulator. In particular embodiments, the ground electrode is tubular in shape and includes an inner spark surface ring spaced in surrounding relation to the center electrode to create a spark gap, an outer ring attached to the shell, and a plurality of rounded spokes connecting the inner and outer rings. In a particular embodiment, the ground and center electrodes accommodate attachment of precious metal alloys to increase electrode surface life. In another embodiment the ground electrode and insulator is coaxial to the center electrode.

A spark plug for a stationary, gas-powered internal combustion engine, having a metallic body, an insulator mounted in a passage of the body, a center electrode passing through the insulator, a ground electrode mounted on the body that, together with the center electrode, forms a spark air gap, and a cap attached to the body. The cap shields the center and ground electrodes from the combustion chamber after the spark plug is installed in a combustion chamber of the internal combustion engine, and that, together with the body of the spark plug, forms a prechamber in which the center and ground electrodes are located. The cap has at least one opening that permits gas exchange between the prechamber and the space outside of the prechamber. A sensor receiving space is provided in the body of the spark plug, which space opens into the prechamber and serves to receive a pressure sensor in a replaceable manner, and a connecting channel for routing a connecting line of the pressure sensor leads from the sensor receiving space to the end of the body opposite the cap.