Patent application number | Description | Published |
20120217864 | SPARK PLUG - A spark plug having an insulator that can be restrained from cracking in an environment of heating and cooling cycles. The spark plug includes an insulator having an axial bore extending in the direction of the axis, and a center electrode held in one end portion of the axial bore. The center electrode has an outer layer, and a core provided within the outer layer and formed from a material higher in thermal conductivity than the outer layer. After a heat treatment, the outer layer has a high-hardness region having a hardness of 190 Hv or higher and a thickness of 30 μm to 200 μm, and an element supply region having a thickness of 50 μm or more. | 08-30-2012 |
20120293061 | SPARK PLUG - A spark plug including a center electrode and a ground electrode having a gap between the center electrode and the ground electrode, the ground electrode has an outer layer which is formed from an Ni-based alloy and a core portion which is covered by the outer layer and formed from a material having a thermal conductivity higher than that of the outer layer. Further, the melting point of the Ni-based alloy forming the outer layer is 1150° C. or more and 1350° C. or less. | 11-22-2012 |
20130069516 | SPARK PLUG - A spark plug includes a ceramic insulator, a center electrode, a metallic shell, and a ground electrode. The center electrode has a shoulder portion at a forward end portion, which tapers forward with respect to the axial direction. A noble metal tip is joined to the forward end portion of the center electrode through a fusion zone. A spark discharge gap is formed between the noble metal tip and the ground electrode. The shortest distance between the fusion zone and a forward end surface of the noble metal tip is 0.8-1.2 mm. The outside diameter of the fusion zone as measured at a forward end of the fusion zone is smaller than that as measured at a rear end of the fusion zone. An acute angle θ | 03-21-2013 |
20130200774 | SPARK PLUG AND MANUFACTURING METHOD THEREFOR - A spark plug includes a ceramic insulator having an axial hole formed in an axis direction of the spark plug, a center electrode inserted in a front side of the axial hole, a metal shell disposed around the ceramic insulator and a ground electrode joined to a front end portion of the metal shell, wherein the ground electrode has a cross-sectional area of 2.0 mm | 08-08-2013 |
20130293088 | SPARK PLUG - It is an object of the present invention to provide a spark plug having a ground electrode joined securely by electric resistance welding. The spark plug includes a cylindrical metal shell and a ground electrode joined by electric resistance welding to an end portion of the metal shell. The metal shell has a high hardness region formed with a Vickers hardness of 3×10 | 11-07-2013 |
20130313962 | SPARK PLUG - A spark plug including a center electrode; an insulator; a metallic shell; and a ground electrode, wherein at least one of the center electrode and the ground electrode has thereon an intermediate member which connects the center electrode or the ground electrode to a noble metal tip. The intermediate member has a tip-bonding portion to which the noble metal tip is bonded, and an electrode-bonding portion which has a diameter greater than that of the tip-bonding portion, and which is bonded to the center electrode or the ground electrode. The intermediate member contains nickel (Ni) as a main component, and also contains chromium (Cr) in an amount of 15 to 25 wt. %. The intermediate member contains, in a surface portion thereof, silicon (Si) in an amount per unit volume of 0.04 mg/mm | 11-28-2013 |
Patent application number | Description | Published |
20130088139 | SPARK PLUG - A spark plug which exhibits improved resistance to high-temperature oxidation of an electrode, and improved resistance to spark-induced erosion of, improved resistance to oxidation of, and improved joining reliability of a tip joined to the electrode. A spark plug has spark members; each of the spark members has a weight of 1.5 mg or more; and a center electrode and a ground electrode contain Ni as a main component, C in an amount of 0.005% by mass to 0.10% by mass, Si in an amount of 1.05% by mass to 3.0% by mass, Mn in an amount of 2.0% by mass or less, Cr in an amount of 20% by mass to 32% by mass, and Fe in an amount of 6% by mass to 16% by mass. | 04-11-2013 |
20130181596 | SPARK PLUG ELECTRODE, METHOD FOR PRODUCING SAME, SPARK PLUG, AND METHOD FOR PRODUCING SPARK PLUG - A spark plug includes at least one of a center electrode or a ground electrode that is produced by the steps of: mixing a matrix metal with carbon so that the carbon content of the resultant mixture is adjusted to 80 vol. % or less; subjecting the mixture to powder compacting or sintering, to thereby form a core; placing the core in a cup formed of nickel or a metal containing nickel as a main component; and subjecting the cup to cold working. The thus-produced electrode exhibits favorable thermal conductivity and good heat dissipation, by virtue of the small difference in thermal expansion coefficient between the core and an outer shell. The spark plug including the above electrode exhibits excellent durability. | 07-18-2013 |
20130181597 | SPARK PLUG ELECTRODE, METHOD FOR PRODUCING SAME, SPARK PLUG, AND METHOD FOR PRODUCING SPARK PLUG - A spark plug is provided having at least one of a center electrode or a ground electrode. The electrode comprises: a core formed of a composite material containing a matrix metal, the matrix metal being copper or a metal containing copper as a main component, and carbon dispersed in the matrix metal in an amount of 10 to 80 vol. %, the carbon having a thermal conductivity higher than that of the matrix metal. The electrode also contains an outer shell which surrounds the core and which is formed of nickel or a metal containing nickel as a main component. The thus-produced electrode exhibits favorable thermal conductivity and good heat dissipation, by virtue of the small difference in thermal expansion coefficient-between the core and an outer shell. The spark plug including the above electrode exhibits excellent durability. | 07-18-2013 |