A prechamber sparkplug includes a housing having a nozzle with a prechamber formed therein, and each of a first set and a second set of electrode prongs within the prechamber. The second set of electrode prongs downwardly depend from attachment points to the housing, and form, together with the first set of electrode prongs, spark gaps within the prechamber. Each of the anode-cathode pairs formed by the sets of electrode prongs is spaced radially inward a clearance distance from the prechamber wall to position the spark gaps in a flow of swirled gases. The flow of swirled gases displaces a flame kernel formed at the spark gaps to inhibit quenching.

A multi-ignition coil control system includes a spark plug including first and second center electrodes, and first and second ground electrodes spaced apart from the center electrodes by a predetermined distance, a first ignition coil including a primary coil, and a secondary coil in which a discharge current is generated by electromagnetic induction with the primary coil, and a second ignition coil including a primary coil, and a secondary coil in which a discharge current is generated by electromagnetic induction with the primary coil, wherein one end of the secondary coil of the first ignition coil and one end of the secondary coil of the second ignition coil are electrically connected to one of the center electrodes, and the other end of the secondary coil of the first ignition coil and the other end of the secondary coil of the second ignition coil are electrically connected to the other of the center electrodes.

A prechamber spark plug that includes an internal reservoir, a flow passage portion, and a prechamber and is designed to operate efficiently across a wide variety of operating conditions and ranges. The internal reservoir includes upper and lower internal reservoir sections, the prechamber includes upper and lower prechamber sections, and the flow passage portion fluidly connects the lower internal reservoir section and the upper prechamber section so that burnt air/fuel gases can be exchanged therebetween. A ground electrode assembly with a ground electrode ring may be positioned in the prechamber such that it separates the upper and lower prechamber sections, whereas a modular prechamber cap may be used to define the shape and size of the lower prechamber section. In one example, the flow passage portion has a total cross-sectional area (AFC) and the internal reservoir has a total volume (VRES), and the ratio AFC:VRES is greater than or equal to 0.015 (1/mm).

Spark plugs are disclosed that include electrode arrangements to improve the charge flow into and out of the annular volume around the insulator nose and a pre-chamber volume of a pre-chamber device, thus directing a purge of exhaust gases trapped in the annular volume to a space formed by the exterior of the spark plug body and the interior of the pre-chamber device.

A spark plug includes a central electrode member and an outer electrode member. The central electrode member includes a central base and a plurality of electrode prongs extending in an axial direction from the central base. The outer electrode member surrounds the central electrode member. The outer electrode member includes a wall that is radially spaced from the plurality of electrode prongs to allow a series of electric arcs to form between the wall and the plurality of electrode prongs. The outer electrode member and the central electrode member are sized and positioned relative to one another such that a first rate of wear of the outer electrode member, along a longitudinal axis of the spark plug, is substantially equal to a second rate of wear of the central electrode member along the longitudinal axis.

A spark plug includes a central electrode member and an outer electrode member. The central electrode member includes a central base and a plurality of electrode prongs extending in an axial direction from the central base. The outer electrode member surrounds the central electrode member. The outer electrode member includes a wall that is radially spaced from the plurality of electrode prongs to allow a series of electric arcs to form between the wall and the plurality of electrode prongs. The outer electrode member and the central electrode member are sized and positioned relative to one another such that a first rate of wear of the outer electrode member, along a longitudinal axis of the spark plug, is substantially equal to a second rate of wear of the central electrode member along the longitudinal axis.

A spark plug having multiple spark gaps, where at least one of the spark gaps is located within a prechamber. The spark plug may include a first center wire assembly, a second center wire assembly, an insulator, a metallic shell, a first sparking area with a prechamber cap and a ground electrode for a prechamber spark gap, and a second sparking area with a ground electrode for a main chamber spark gap. The spark plug is designed to maximize engine performance and/or operation by utilizing the multiple spark gaps, where the prechamber spark gap may be used for certain operating conditions where such a spark gap is advantageous and the separate main chamber spark gap may be used for other conditions where a main chamber spark gap is advantageous.

A spark plug includes a central electrode member and an outer electrode member. The central electrode member includes a central base and a plurality of electrode prongs extending in an axial direction from the central base. The outer electrode member surrounds the central electrode member. The outer electrode member includes a wall that is radially spaced from the plurality of electrode prongs to allow a series of electric arcs to form between the wall and the plurality of electrode prongs. The outer electrode member and the central electrode member are sized and positioned relative to one another such that a first rate of wear of the outer electrode member, along a longitudinal axis of the spark plug, is substantially equal to a second rate of wear of the central electrode member along the longitudinal axis.

A method for manufacturing a spark plug electrode system including a ground electrode and a center electrode, which are connected to each other by a joining area, formed from a one-piece spark plug electrode base body made up of spark plug electrode material.

A spark plug for use with an engine block/cylinder head having a threaded bore and also for use with a spark plug wrench and an ignition wire. Also, an improved method for constructing a spark plug, the spark plug including a metal shell having a hex nut, a seat, a flange, a bore and threads. A ground electrode is associated with the shell and an insulator assembly occupies the bore and is gripped by the flange. The method includes the steps of forming the hex nut and the seat by carrying out operations on a blank, roiling the threads, fitting the insulator assembly into the bore, deforming the flange to capture the insulator, and forming the negative electrode by machining the blank.