Abstract: A spark plug has a firing pad attached to a center electrode or to a ground electrode. The firing pad is attached via laser welding and has a sparking surface with an overall fused area and an unfused area. In one or more embodiments, the overall fused area is located in part or more inboard of a peripheral edge of the firing pad.

Abstract: A method of manufacturing a spark plug (20) for being threaded into a cylinder head (28) of an internal combustion engine is provided. The spark plug (20) includes a shell (24) with threads (26) disposed at a predetermined rotational position (a) relative to a shell outer surface (64) and ground electrode (34). The position of the threads (26) relative to the ground electrode (34) places the ground electrode (34) in a desired position in the combustion chamber (22) and relative to components of the engine, thus allowing the ground electrode (34) to provide a robust and reliable ignition. When multiple spark plugs (20) are formed, the threads (26) in each of the shells (24) are repeatedly and accurately formed at the predetermined rotational position (?) by locating the ground electrode (34), threads (26), and dies (76) of a thread forming apparatus (102) in specific locations.

Abstract: A spark plug has a firing pad attached to a center electrode or to a ground electrode. The firing pad is attached via laser welding and has a sparking surface with an overall fused area and an unfused area. In one or more embodiments, the overall fused area is located in part or more inboard of a peripheral edge of the firing pad.

Abstract: A spark plug has a firing pad attached to a center electrode or to a ground electrode. The firing pad is attached via laser welding and has a sparking surface with an overall fused area and an unfused area. In one or more embodiments, the overall fused area is located in part or more inboard of a peripheral edge of the firing pad.

Abstract: A method of manufacturing a spark plug (20) for being threaded into a cylinder head (28) of an internal combustion engine is provided. The spark plug (20) includes a shell (24) with threads (26) disposed at a predetermined rotational position (a) relative to a shell outer surface (64) and ground electrode (34). The position of the threads (26) relative to the ground electrode (34) places the ground electrode (34) in a desired position in the combustion chamber (22) and relative to components of the engine, thus allowing the ground electrode (34) to provide a robust and reliable ignition. When multiple spark plugs (20) are formed, the threads (26) in each of the shells (24) are repeatedly and accurately formed at the predetermined rotational position (a) by locating the ground electrode (34), threads (26), and dies (76) of a thread forming apparatus (102) in specific locations.

Abstract: A spark plug having a metal shell, an insulator, a center electrode, a ground electrode, and a multi-layer sparking component. The multi-layer sparking component is attached at a firing end of the ground electrode and includes a thin precious metal layer formed overtop a base metal layer and, according to some embodiments, overhangs the end of the ground electrode. The precious metal and base metal layers may be pre-manufactured together as a bi-metal ribbon, sheet or laminate before the multi-layer sparking component is attached to the ground electrode.

Abstract: A spark plug has a firing pad attached to a center electrode or a ground electrode by way of a fused portion. In one or more embodiments, the firing pad is composed of a precious metal material. The fused portion can be formed in such a way that a material composition thereof at a sparking surface of the firing pad has a greater percentage of the precious metal material than a material of the underlying electrode to which the firing pad is attached.

Abstract: A spark plug has a shell, an insulator, a center electrode, a ground electrode, and a firing pad. The firing pad is made of a precious metal material and is attached to the ground electrode. The firing pad has a side surface at a peripheral edge that can be flush or nearly flush with a free end surface of the ground electrode. This construction can help improve ignitability and flame kernel growth of the spark plug during a sparking event, and can provide better thermal management at the attached ground electrode and firing pad.

Abstract: A spark plug includes a metallic shell, an insulator, a center electrode, a ground electrode, and a thin firing pad. The thin firing pad is made from a noble metal and can be attached to the center electrode, the ground electrode, or to both. In some examples, the thin firing pad possesses certain geometric properties and relationships that can improve ignitability and durability of the thin firing pad.

Abstract: A spark plug has a shell, an insulator, a center electrode, a ground electrode, and a firing pad. The firing pad is made of a precious metal material and is attached to the ground electrode. The firing pad has a side surface at a peripheral edge that can be flush or nearly flush with a free end surface of the ground electrode. This construction can help improve ignitability and flame kernel growth of the spark plug during a sparking event, and can provide better thermal management at the attached ground electrode and firing pad.