Abstract: A spark plug electrode includes a thermally conductive core portion and a weldable core portion that are aligned in series within a multi-piece core assembly to improve the heat management and attachment characteristics of the electrode. The thermally conductive core portion, which can be made from a copper-based material, is located towards a firing end of the ground electrode. The weldable core portion can be made from a nickel-based material and is located towards a welding end of the ground electrode. A method of manufacturing is also described for extruding and forming the spark plug electrode with the multi-piece core assembly. The method is designed so that a core interface between the thermally conductive core portion and the weldable core portion does not substantially include any internal voids, and a welding surface where the electrode is attached to a spark plug shell has a nickel-to-nickel interface, but does not substantially include any copper.

Abstract: A prechamber spark plug having a thermally enhanced prechamber cap with a thermally conductive core, such as one made from a copper-, aluminum- and/or silver-based material. Due to its location and function, a prechamber cap is exposed to thermal energy from a pre-combustion process taking place within a prechamber, as well as thermal energy from a combustion process taking place in a main combustion chamber. Thus, the prechamber cap is being heated on both its interior and its exterior and, if not sufficiently cooled, can become so hot that it undesirably triggers preignition events in the engine. The thermally enhanced prechamber cap may include a main body with an interior surface and an exterior surface, a thermally conductive core with one or more thermal segments and insert segments, and one or more openings extending between a prechamber and a main combustion chamber, where each opening extends through an insert segment that is designed to resistant to corrosion and/or erosion.

Abstract: An electrode tip assembly for a spark plug includes an electrode tip that is formed on an electrode base using an additive manufacturing process, such as a powder bed fusion technique, after which the electrode base is welded to an electrode body. The electrode base includes a welding side and an additive manufacturing side, and the electrode tip includes a plurality of laser deposition layers built on the additive manufacturing side of the electrode base.

Abstract: A spark plug electrode with an electrode tip formed on an electrode base using an additive manufacturing process, such as a powder bed fusion technique. The spark plug electrode includes an intermediate layer located between the electrode tip and the electrode base, where the intermediate layer has a coefficient of thermal expansion (CTE) that is between that of the electrode base and the electrode tip and includes a whole area connection. In some examples, the whole area connection is non-uniform in thickness so that it is thicker in one section than it is in another section.

Abstract: A spark plug and method of manufacturing, where the spark plug meets particular geometric relationships to maintain and potentially improve dielectric performance while downsizing other plug dimensions. The spark plug includes an insulator that can withstand higher voltages while having areas with a reduced cross-sectional thickness. In some embodiments, the insulator has a dielectric strength of 42 kV/mm or more with a radial thickness at the internal seal of 1.5 to 1.6 mm, inclusive, and a radial thickness at a gasket of 0.6 to 0.9 mm, inclusive.

Abstract: A spark plug electrode includes an electrode tip that is attached to or formed on an electrode base so that the electrode tip is directly thermally coupled to a heat dissipating core through an opening in the electrode base. This direct thermal coupling may take place on a side surface of a ground electrode or a center electrode and removes thermal energy away from the electrode tip in order to reduce thermal and/or other stresses. The heat dissipating core may have one or more core extensions that diverge or branch off of a core main body and extend into the opening in the electrode base for better thermal coupling to the electrode tip. The electrode tip can be attached to the electrode base via welding or it can be formed on the electrode base using a suitable additive manufacturing process, such as a powder bed fusion technique.

Abstract: A spark plug electrode with one or more electrode tip(s) formed on one or more electrode base(s) using an additive manufacturing process, such as a powder bed fusion technique, such that each electrode tip overhangs an edge of a corresponding electrode base. The spark plug electrode may be a center electrode, a ground electrode, or an annular ground electrode and can be provided according to a number of different configurations. Each electrode tip includes a precious metal-based material, such as an iridium- or platinum-based alloy, and a plurality of laser deposition layers, and each electrode tip can be secured to an electrode base with a weldless joint. An additive manufacturing process is also provided.

Abstract: An electrode material for a spark plug includes 22-46 wt % iron (Fe), inclusive, 20-40 wt % nickel (Ni), inclusive, 13-42 wt % cobalt (Co), inclusive, and one or more additional elements selected from aluminum (Al), titanium (Ti), chromium (Cr), boron (B), and niobium (Nb), wherein the electrode material has a coefficient of thermal expansion (CTE) from room temperature to 200° C. that is less than or equal to 11.0×10?6/° C. In another example, the electrode material includes greater than or equal to 32 wt % iron (Fe), greater than or equal to 36 wt % nickel (Ni), and one or more additional elements selected from aluminum (Al), chromium (Cr), and cobalt (Co). In advantageous embodiments, the electrode material includes greater than or equal to 22 wt % cobalt (Co). Replacing nickel with a higher percentage of cobalt can help reduce the coefficient of thermal expansion (CTE) of the electrode material.

Abstract: A spark plug electrode with an electrode tip formed on an electrode base using an additive manufacturing process, such as a powder bed fusion technique. The spark plug electrode includes an electrode base that at least partially surrounds a heat dissipating core, an electrode tip that is formed on the electrode base and includes a precious metal-based material, and a thermal coupling zone that directly thermally couples the electrode tip to the heat dissipating core. In some examples, the electrode tip is formed on an electrode base that has been cut or severed to expose a portion of the heat dissipating core, such that the electrode tip is formed directly on the heat dissipating core using additive manufacturing.

Abstract: 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).

Abstract: A composite sparking component for a spark plug that has a thin precious metal layer with a series of grooves attached to an underlying base layer. The grooves allow the precious metal layer, and hence the entire composite sparking component, to be more easily bent or formed into a desired shape, while at the same time minimizing the amount of precious metal and providing enhanced sparking sites along the edges of the grooves. In one example, the composite sparking component is a sleeve-shaped component attached to a center electrode. In a different example, the composite sparking component is a ring-shaped component attached to a ground electrode. The precious metal layer may be bonded to the base layer in the form of a bimetal laminate structure, or the precious metal layer can be built on the base layer with the use of additive manufacturing, to cite several possibilities.

Abstract: A spark plug electrode with an electrode tip formed on an electrode base using an additive manufacturing process, such as a powder bed fusion technique. The spark plug electrode includes an electrode base that at least partially surrounds a heat dissipating core, an electrode tip that is formed on the electrode base and includes a precious metal-based material, and a thermal coupling zone that directly thermally couples the electrode tip to the heat dissipating core. In some examples, the electrode tip is formed on an electrode base that has been cut or severed to expose a portion of the heat dissipating core, such that the electrode tip is formed directly on the heat dissipating core using additive manufacturing.

Abstract: A pre-chamber spark plug includes a shell extending along a longitudinal axis and comprising an inner surface. The pre-chamber spark plug further includes an insulator including an outer surface. The pre-chamber spark plug further includes a pre-chamber cap connected to the shell. The pre-chamber cap and the shell together forms a pre-chamber. The pre-chamber spark plug further includes an annular reservoir defined between the outer surface of the insulator and the inner surface of the shell. The annular reservoir is spaced apart from the pre-chamber with respect to the longitudinal axis. The pre-chamber spark plug further includes a plurality of projections disposed between the annular reservoir and the pre-chamber with respect to the longitudinal axis. The plurality of projections at least partially define a plurality of flow passages therebetween.

Abstract: 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.

Abstract: A metal shell for a spark plug is made from a steel material that has increased carbon content and, in some embodiments, boron as well. The steel material is well-suited for extrusion because of its ductility, while maintaining requisite strength. The spark plug shell may have a reduced outer diameter (ODHL) at a crimped hot lock region, such as the case when the shell is used in smaller diameter spark plugs, such as M8 and M10 plugs. According to a non-limiting example, the spark plug shell steel material comprises 0.20-0.55 wt % carbon, inclusive.

Abstract: A prechamber spark plug for an internal combustion engine with the following features: a body with an external thread at its front end for screwing the spark plug into the engine; the external thread has a center line and begins with a thread start at the front end; the body has a passage in which an insulator is fastened and a center electrode protrudes from the front end of this insulator; at the front end of the body, a prechamber-forming cap is provided, which delimits a prechamber and shields the center electrode from a combustion chamber of the engine after the spark plug has been installed in the engine; the cap has at least one opening, which has a predefined orientation in relation to the thread start and is oriented obliquely to the center line of the external thread so as to permit a gas exchange between the prechamber and the space outside the prechamber.

Abstract: An insulator arrangement for a spark plug arrangement, in particular for a prechamber spark plug, with an elongated body that has an insulator arrangement longitudinal bore for accommodating a center electrode arrangement and has a front end. A sealing shoulder is formed on an outer circumferential section of the body. An axial transition section is formed between the sealing shoulder and the front end of the body. The front end of the body is designed such that at least 50% of a gas flow impinging thereon in a first direction is deflected in a direction opposite to the first direction.

Abstract: A spark plug for generating an axially extending surface spark between a sparking tip of the center electrode and a seal supporting sparking projection located at an internal step portion of the metal shell. In one embodiment, the spark plug is a pre-chamber spark plug having a pre-chamber cap attached to a distal end of the metal shell. The spark plug can allow for unobstructed flame propagation through the pre-chamber, without having the flame obstructed by narrow gaps or a separate ground electrode.

Abstract: A pre-chamber spark plug for an internal combustion engine having: a body with a passage in which an insulator is fastened and a center electrode protrudes; at least one ground electrode extending in a straight line forms a spark gap with the center electrode; a pre-chamber-forming cap which delimits a pre-chamber and shields the center and ground electrodes from a combustion chamber after the spark plug has been installed in the engine, wherein the cap has at least one opening which permits a gas exchange between the pre-chamber and the space outside the pre-chamber. The ground electrode includes a reinforcing component welded to an end surface of a supporting component, and the supporting component is either welded to an end surface of the body or is welded to a step that is formed on the end surface.

Abstract: A pre-chamber spark plug having a shell, an insulator disposed at least partially within the shell, a center electrode disposed at least partially within the insulator, a ground electrode forming a spark gap with the center electrode, and a pre-chamber cap connected to the shell and forming a pre-chamber. The pre-chamber cap includes two or more openings that are configured so that at least one inflowing fuel-air mixture jet is directed to a pre-chamber wall gap so as to flush out or remove gas from a previous ignition cycle. The two or more openings are angled so that a first inflowing fuel-air mixture jet of a first opening does not intersect with a second inflowing fuel air-mixture jet of a second opening.