Title:
【発明の名称】スパークプラグ
Document Type and Number:
Japanese Patent JP3000955
Kind Code:
B2
Abstract:
A process of producing a spark plug having an improved consumption resistance is provided. The spark plug comprises a noble metal chip composed of an Iridium (Ir) alloy material and includes an insulator enclosing a center electrode and a ground electrode, which has a facing portion facing the tip of the center electrode. The chip may be disposed on the tip of the center electrode, the facing portion of the ground electrode or both. The Ir alloy material consists of Ir and a metal that has a higher oxidation resistance than Ir and forms a solid solution with Ir at all proportions to prevent oxidation evaporation of Ir. In order to prevent surface cracking, the chip is produced by elongating an ingot of the Ir alloy material through hot forging to form a bar having a fine fiber texture. Then, the chip is hot rolled, hot wire drawn and cut to the desired length.
Inventors:
Hironori Nagamura
Nobuo Abe
Nobuo Abe
Application Number:
JP9764697A
Publication Date:
January 17, 2000
Filing Date:
April 15, 1997
Export Citation:
Assignee:
株式会社デンソー
International Classes:
H01T13/20; H01T13/39; H01T21/02; (IPC1-7): H01T13/39; H01T13/20; H01T21/02
Domestic Patent References:
| JP4329286A | ||||
| JP6112261A | ||||
| JP7268574A | ||||
| JP3207501A | ||||
| JP1022052A | ||||
| JP1319284A | ||||
| JP2153053A | ||||
| JP5343156A | ||||
| JP6258114B2 | ||||
| JP6411579B2 |
Other References:
【文献】欧州特許出願公開702093(EP,A1)
Attorney, Agent or Firm:
Yoji Ito (1 person outside)