Patent application number | Description | Published |
20090033195 | SPARK PLUG FOR INTERNAL COMBUSTION ENGINE AND METHOD OF MANUFACTURING THE SAME - A spark plug for an internal combustion engine, includes: a cylindrical insulating body; a center electrode; a cylindrical metal shell; and a ground electrode, as defined herein, wherein the noble metal tip is bonded to the ground electrode via a molten bond, and when viewed in a cross-section including a center axis of the noble metal tip along a longitudinal direction of the ground electrode, a sum of a cross-sectional area of a base-end-side molten bond (A) positioned at a base end side of the ground electrode and a cross-sectional area of a front-end-side molten bond (B) positioned at a front end side of the ground electrode is equal to or greater than 4 mm | 02-05-2009 |
20090071429 | SPARK PLUG AND INTERNAL COMBUSION ENGINE IN WHICH THE SPARK PLUG IS DISPOSED - To provide a spark plug with improved heat resistance and an internal combustion engine in which that spark plug is mounted where there is good conduction of the heat near the opening on the combustion chamber side of the mounting hole for the spark plug provided in the engine and the effects of thermal stress occurring near that opening are mitigated. A cylindrical part without threads formed thereon is provided on the leading end side of a metal housing of a spark plug and the thermal stress applied to a mounting hole is mitigated by avoiding close contact with the mounting hole of an engine head. Furthermore, the spark plug has a mounting structure in which the leading end surface of the cylindrical part is disposed 1.55 mm or more to the base end side in a mounting hole in the direction of the axial line O with respect to the wall surface inside the combustion chamber. By this means, the metal housing does not easily take up the heat that accompanies combustion of the air-fuel mixture inside the combustion chamber at the cylindrical, part so there may be good heat conduction. | 03-19-2009 |
20090127997 | SPARK PLUG FOR INTERNAL COMBUSTION ENGINE - A spark plug including: a rod-shaped center electrode; an insulator; a metal shell; a ground electrode joined to the metal shell and bent toward the center electrode; a noble metal tip joined to an end portion of the ground electrode and opposing a leading end portion of the center electrode via a gap; and a bulge portion. A part of the noble metal tip is embedded in the ground electrode, and another part of the noble metal tip protrudes from a distal end surface of the ground electrode. A relationship A≧0.25 mm is satisfied where A (mm) is a protruding length of the noble metal tip from the distal end surface. The bulge portion covers a center part of a boundary between the noble metal tip and the end surface in a width direction. | 05-21-2009 |
20090134764 | SPARK PLUG FOR INTERNAL COMBUSTION ENGINE AND METHOD FOR PRODUCING THE SPARK PLUG - A spark plug including: a ground electrode including a thick portion provided on a base end side, a thin portion provided on a distal end side, and a stepped portion provided on an inner peripheral surface between the thick portion and the thin portion; a noble metal tip partially embedded in an inner peripheral surface of the thin portion; and a bulge portion provided on the inner peripheral surface of the thin portion between the stepped portion and the noble metal tip. When viewed from a side surface of the ground electrode, a relationship [a protruding height of the noble metal tip from the inner peripheral surface of the thin portion]≧[a protruding height of the bulge portion from the inner peripheral surface of the thin portion]. | 05-28-2009 |
20090140624 | SPARK PLUG INTERNAL COMBUSTION ENGINE AND METHOD FOR PRODUCING THE SPARK PLUG - A spark plug including: a center electrode; a substantially cylindrical insulator; a cylindrical metal shell; a ground electrode having a base end joined to a leading end portion of the metal shell and a distal end bent toward the axis line. The ground electrode includes: a thick portion provided on a base end side, a thin portion provided on a distal end side, and a stepped portion provided on an inner peripheral surface between the thick portion and the thin portion. A noble metal tip is joined to and partially embedded in the inner peripheral surface of the thin portion and disposed to form a gap between the noble metal tip and the leading end portion of the center electrode. | 06-04-2009 |
20090160304 | SPARK PLUG FOR INTERNAL COMBUSTION ENGINE - A spark plug includes a ground electrode formed with a flat region and a convex curved region on an outer peripheral surface thereof. The flat region is located on a front end of the ground electrode and has a length of 0.2 mm or more from a front end face of the ground electrode in a longitudinal direction of the ground electrode. The ground electrode satisfies the following dimensional condition (1) with respect to first and second cross sections of the ground electrode taken through the convex curved region and the flat region in directions perpendicular to the longitudinal direction of the ground electrode, | 06-25-2009 |
20090160305 | SPARK PLUG - A spark plug includes an outer electrode including an outer electrode tip of which a distal end surface is spaced from an outer peripheral surface of a leading end portion of a center electrode to define a spark discharge gap. A protruding insulator portion of a cylindrical insulator protrudes at least 1.0 mm from a leading end surface of a cylindrical metal shell. A protruding center electrode portion of the center electrode protrudes at least 3.5 mm from the leading end surface of the cylindrical metal shell. A relationship (θ | 06-25-2009 |
20090322198 | METHOD OF PRODUCING SPARK PLUG AND SPARK PLUG PRODUCED BY THE METHOD - For producing a spark plug that has a high dimensional accuracy in the spark gap, a method is disclosed which comprises (a) preparing a semi-finished spark plug unit ( | 12-31-2009 |
20100206256 | SPARK PLUG FOR INTERNAL COMBUSTION ENGINE - There is provided a spark plug for an internal combustion engine, including: a center electrode extending in the direction of an axis of the spark plug and having a core of higher thermal expansion coefficient than that of a front end thereof, the center electrode including a flanged portion radially outwardly protruding on a rear side thereof and a cylindrical portion located closer to a front end of the spark plug than the flanged portion and being smaller in diameter than the flanged portion; an insulator having an axial hole in the direction of the axis to retain the flanged portion in the axial hole with the cylindrical portion held in a loose-fit state in the axial hole; and a metal shell accommodating the insulator, wherein the spark plug satisfies the following condition: Cb08-19-2010 | |
20110175514 | SPARK PLUG FOR INTERNAL COMBUSTION ENGINE - A spark plug without any noble metal chip on a ground electrode and capable of enhancing the ignition property, prolonging the life and ensuring a sufficiently high strength of the ground electrode is provided. The spark plug | 07-21-2011 |
20110175515 | SPARK PLUG - It is an object of the present invention to provide a spark plug that can be produced at low cost and secure compatibility between ignition performance and durability. The spark plug according to the present invention includes a center electrode and a ground electrode having an inner surface facing the center electrode, characterized in that; the ground electrode has a protrusion and a hole; the protrusion protrudes from the inner surface by a protruding length A of 0.4 to 1 mm and has a first straight portion with a projected first straight portion area S | 07-21-2011 |
20120013262 | IGNITION APPARATUS FOR PLASMA JET IGNITION PLUG AND IGNITION SYSTEM - An ignition apparatus for an ignition plug which uses a positive polarity power supply, which can cause the ignition plug to generate spark discharge while using its center electrode as a negative electrode, and which can adjust the timing of supply of electric energy to the ignition plug and the timing of charging of capacitors. The ignition apparatus is adapted to cause the ignition plug to generate spark discharge while using its center electrode as a negative electrode, and includes a positive power supply, and energy supply units. Each energy supply unit includes a capacitor connected at one end to the power supply and connected at the other end to the ignition plug; a switching unit for charging; and a switching unit for energy supply. | 01-19-2012 |