Disclosed are a flame-ejecting spark plug, and an internal combustion engine and an automobile having same. On the basis of a conventional spark plug, a space near to an electrode is closed to form a cavity (10), an end face is provided with at least one first hole (11), and a side face is provided with at least one second hole (13). A mixture of air and fuel enters the cavity (10) through the first hole (11) and the second hole (13). Electric discharge between the electrodes produces a spark igniting the combustible gas within the cavity (10), and the flame extends in the cavity (10) and the temperature and pressure rise. The flame is ejected from the first hole (11) and the second hole (13) to form a plurality of columnar flames, and the flame penetrates the combustible gas in a combustion chamber and a cylinder to realize stereoscopic ignition, large-area ignition and high-energy ignition of the combustible gas in the combustion chamber.

Disclosed are a flame-ejecting spark plug, and an internal combustion engine and an automobile having same. On the basis of a conventional spark plug, a space near to an electrode is closed to form a cavity (10), an end face is provided with at least one first hole (11), and a side face is provided with at least one second hole (13). A mixture of air and fuel enters the cavity (10) through the first hole (11) and the second hole (13). Electric discharge between the electrodes produces a spark igniting the combustible gas within the cavity (10), and the flame extends in the cavity (10) and the temperature and pressure rise. The flame is ejected from the first hole (11) and the second hole (13) to form a plurality of columnar flames, and the flame penetrates the combustible gas in a combustion chamber and a cylinder to realize stereoscopic ignition, large-area ignition and high-energy ignition of the combustible gas in the combustion chamber.

Disclosed is a spark plug in which a first electrode has a tip joined to an electrode base through a fusion zone. In a cross section of the first electrode taken along a center axis, an interface of the fusion zone and a tip includes a first region, a second region and a base point present on at least one side of the cross section. The base point is a point connection of the first and second regions and is located farthest away from the imaginary straight line in the direction parallel to the center axis. The base point is positioned so as to satisfy a condition of 0.1X/W0.4 where W is a length of the interface in a direction perpendicular to the center axis; and X is a distance between the base point and the center axis.

Disclosed is a spark plug in which a first electrode has a tip joined to an electrode base through a fusion zone. In a cross section of the first electrode taken along a center axis, an interface of the fusion zone and a tip includes a first region, a second region and a base point present on at least one side of the cross section. The base point is a point connection of the first and second regions and is located farthest away from the imaginary straight line in the direction parallel to the center axis. The base point is positioned so as to satisfy a condition of 0.1X/W0.4 where W is a length of the interface in a direction perpendicular to the center axis; and X is a distance between the base point and the center axis.

An ignition device for an internal combustion engine is provided which includes a spark plug and a controller. The spark plug has a housing with a head protruding into a combustion chamber of the engine. The head has at least a portion located downstream of a spark gap of the spark plug in an air-fuel mixture flow within the combustion chamber. The controller works to perform a plurality of discharge events in the spark plug in each cycle of an operation of the engine. This improves the ability of the spark plug to ignite the mixture without need to increase an ignition energy.

An ignition device for an internal combustion engine is provided which includes a spark plug and a controller. The spark plug has a housing with a head protruding into a combustion chamber of the engine. The head has at least a portion located downstream of a spark gap of the spark plug in an air-fuel mixture flow within the combustion chamber. The controller works to perform a plurality of discharge events in the spark plug in each cycle of an operation of the engine. This improves the ability of the spark plug to ignite the mixture without need to increase an ignition energy.

A spark plug includes: a center electrode; a ground electrode that is provided such that a gap for spark discharge is formed between the center electrode and the ground electrode; and a plug cover covering the center electrode and the ground electrode to form an auxiliary chamber. The plug cover is provided with plural through holes. A relationship of 80<A/B<5000 is satisfied, where a sphere has a center at a midpoint of a line connecting the center electrode and the ground electrode at a shortest distance on an axial line and contacts a point located closest from the center on each of inner open ends of the through holes. A mm.sup.3 is a volume of a region of the auxiliary chamber, which is present in the sphere, and B mm.sup.2 is an average area of the inner open ends of the through holes.

A spark plug includes: a center electrode; a ground electrode that is provided such that a gap for spark discharge is formed between the center electrode and the ground electrode; and a plug cover covering the center electrode and the ground electrode to form an auxiliary chamber. The plug cover is provided with plural through holes. A relationship of 80<A/B<5000 is satisfied, where a sphere has a center at a midpoint of a line connecting the center electrode and the ground electrode at a shortest distance on an axial line and contacts a point located closest from the center on each of inner open ends of the through holes. A mm.sup.3 is a volume of a region of the auxiliary chamber, which is present in the sphere, and B mm.sup.2 is an average area of the inner open ends of the through holes.

A spark plug includes: a center electrode; a ground electrode that is provided such that a gap for spark discharge is formed between the center electrode and the ground electrode; and a plug cover covering the center electrode and the ground electrode to form an auxiliary chamber. The plug cover is provided with plural through holes. A relationship of 80<A/B<5000 is satisfied, where a sphere has a center at a midpoint of a line connecting the center electrode and the ground electrode at a shortest distance on an axial line and contacts a point located closest from the center on each of inner open ends of the through holes. A mm.sup.3 is a volume of a region of the auxiliary chamber, which is present in the sphere, and B mm.sup.2 is an average area of the inner open ends of the through holes.

A spark plug includes: a center electrode; a ground electrode that is provided such that a gap for spark discharge is formed between the center electrode and the ground electrode; and a plug cover covering the center electrode and the ground electrode to form an auxiliary chamber. The plug cover is provided with plural through holes. A relationship of 80<A/B<5000 is satisfied, where a sphere has a center at a midpoint of a line connecting the center electrode and the ground electrode at a shortest distance on an axial line and contacts a point located closest from the center on each of inner open ends of the through holes. A mm.sup.3 is a volume of a region of the auxiliary chamber, which is present in the sphere, and B mm.sup.2 is an average area of the inner open ends of the through holes.