A multi-electrode spark plug having a large spark target volume is disclosed. The spark plugs have a plurality of ground electrode rods which extend from the base of the spark plug and are twisted around center electrode to provide a plurality of substantially equidistant spark points relative to the center electrode. The spark points are formed in parallel and around the elongated axis of the spark plug. This configuration enables the spark to be created where the localized concentration of fuel to air is richer, such as that which may exist when the engine is operating with lower revolutions per minute. Test results indicate that automobiles equipped with the multi-electrode spark plugs exhibit improved fuel economy, and substantially reduced emissions and air pollution.

An igniter for a spark ignition system includes a support body fabricated from an electrically insulating material and a metal casing disposed outwardly of and at least partially surrounding the support body. The metal casing has a structure for connecting the metal casing to ground. At least two rod-shaped first electrodes are supported one relative to another by the support body and are electrically isolated one from the other by the support body. Each first electrode has a first end that protrudes from a first end of the support body at a spark forming end of the igniter. The support body is disposed at least partly within an axial channel of a generally cylindrically-shaped second electrode. The second electrode projects past the support body at the spark forming end of the igniter and cooperates with the first ends of the at least two first electrodes to define at least two spark gaps. The second electrode is electrically isolated from the metal casing by an air gap. During use the first electrodes receive a first voltage that is higher than ground and the second electrode receives a second voltage that is lower than the first voltage. A first spark is formed within a first one of the at least two spark gaps and a second spark is formed within a second one of the at least two spark gaps.

A pre-chamber assembly for an internal combustion engine is disclosed. The pre-chamber assembly may have a pre-chamber main body configured to be mounted to the internal combustion engine and defining at least a portion of a pre-chamber extending along a longitudinal axis. The pre-chamber assembly may also have an ignition electrode. The ignition electrode may have a center electrode and at least one electrode arm extending from the center electrode at least partially into the pre-chamber. The at least one electrode arm may extend in both a radial direction with respect to the longitudinal axis and an axial direction with respect to the longitudinal axis. Additionally, the pre-chamber assembly may have a mass element including at least one radial inner face facing the at least one electrode arm. The at least one radial inner face may be non-parallel with respect to the longitudinal axis.

A spark plug combustion ionization sensor for measuring ion current inside the cylinder of an internal combustion engine. The sensor measures ion current which flows when the energy released during combustion ionizes the air inside the cylinder, and thus can detect combustion and emission parameters. The spark plug combustion ionization sensor generally includes an insulated, dedicated sensing electrode, separate from the sparking electrode of a spark plug. The sensing electrode may also be shielded to further reduce interference such as electromagnetic interference (EMI). The use of a dedicated electrode allows for ion current measurement with less electromagnetic noise from the ignition process, and also eliminates the need for circuitry that is typically necessary when the sparking electrode is also used to sense ion current.

A pre-chamber spark plug for igniting a fuel-air mixture in an internal combustion engine, in particular a gasoline engine, comprises a spark plug body (1) having a pre-chamber housing (2) and a cap (4) which at least partially closes the pre-chamber (3), and further comprises a ground electrode (11) in the spark plug body (1) as well as a central electrode (7) which protrudes into the pre-chamber (3); the ground electrode (11) has an annular shape and, on the inner surface thereof, includes at least one ignition area (17) designed as a cam (16) as well as a radially inward extending protrusion (18) as a baffle (19).

A multi-electrode spark plug having a large spark target volume is disclosed. The spark plugs have a plurality of ground electrode rods which extend from the base of the spark plug and are twisted around center electrode to provide a plurality of substantially equidistant spark points relative to the center electrode. The spark points are formed in parallel and around the elongated axis of the spark plug. This configuration enables the spark to be created where the localized concentration of fuel to air is richer, such as that which may exist when the engine is operating with lower revolutions per minute. Test results indicate that automobiles equipped with the multi-electrode spark plugs exhibit improved fuel economy, and substantially reduced emissions and air pollution.

A corona igniter comprises an electrode with a central extended member extending along a central axis and a crown extending radially outwardly from the central extended member. The central extended member has an extended length and the crown has a crown length. The extended length is greater than the crown length such that the extended member approaches a piston more closely than the crown. In addition, the firing tips of the crown each present a first spherical radius which is less than a second spherical radius of the central extended member. Thus, if arcing occurs, it forms from the central extended member, rather than from the crown. Accordingly, the firing tips of the crown experience less wear and remain sharp. In addition, due to the sizes of the spherical radii, corona discharge is more likely to form from the firing tips than from the central extended member.

A spark plug having a center conductor, an insulator surrounding the center conductor, a body surrounding the insulator, and a center electrode connected in an electrically conductive manner to the center conductor, wherein the center electrode delimits a spark gap with its front face. The spark plug has two bar-shaped ground electrodes that are connected in an electrically conductive manner to the body, that delimit the spark gap, and that are adjacent to one another and spaced apart from one another in the region of the spark gap.

A method for producing a spark plug including a spark plug electrode assembly having a center electrode and a ground electrode surrounding the center electrode. The spark plug electrode assembly is formed from a one-piece spark plug electrode base body made of spark plug electrode material, and the ground electrodeand the center electrode are connected to one another by a connecting region, wherein the center electrode and an inner surface of the ground electrode are polygonal. The method includes: a) connecting the spark plug electrode assembly to a spark plug base body, and b) removing the connecting region between the ground electrode and the center electrode.

A spark plug having a longitudinal axis. The spark plug includes: a housing having a bore along the spark plug longitudinal axis and a combustion-chamber-side end face; an insulator arranged at least partially within the housing, and having an insulator base extending from a combustion-chamber-side end face of the insulator to an insulator base neck; a central electrode arranged at least partially within the insulator; and a ground electrode arranged on the housing, the ground electrode and the central electrode being arranged so that the at least one ground electrode forms a spark gap with the central electrode, a width of the spark gap being defined by an inter-electrode distance between the central electrode and the ground electrode. The inter-electrode distance between the central electrode and the ground electrode is not greater than 0.4 mm. The spark gap is formed at least partially within the housing.