Title:
【発明の名称】スパークプラグ
Document Type and Number:
Japanese Patent JP3140006
Kind Code:
B2
Abstract:
In a spark plug, a main air gap (A) is formed between a parallel ground electrode (11) and the end face of a central electrode (2), a semi-surface gap (B) is formed between the end face (12C) of a semi-surface ground electrode (12) and the side face (2A) of the central electrode (2) and a semi-surface air gap (C) is formed between the end face (12C) and the side face (1E) of insulator. In addition, difference in a level E between the height of the lower end face (1D) of the insulator (1) and the height of the upper edge (12B) of the end face 12C of the semi-surface ground electrode 12 is E ≤ +0.7 mm, the distance B of the semi-surface gap (B) is longer than the distance A of the main air gap (A) and the distance C of the semi-surface air gap (C) is shorter than the distance A of the main air gap (A).
Inventors:
Takahiro Suzuki
Kazuya Iwata
Yoshihiro Matsubara
Kazuya Iwata
Yoshihiro Matsubara
Application Number:
JP12450499A
Publication Date:
March 05, 2001
Filing Date:
April 30, 1999
Export Citation:
Assignee:
Nippon Special Ceramics Co., Ltd.
International Classes:
H01T13/20; H01T13/32; H01T13/46; H01T13/52; (IPC1-7): H01T13/46; H01T13/20; H01T13/52
Domestic Patent References:
| JP9199260A | ||||
| JP6081784A | ||||
| JP7130454A | ||||
| JP60180082A | ||||
| JP5859580A | ||||
| JP54109537A | ||||
| JP5326107A | ||||
| JP49120932U |
Attorney, Agent or Firm:
Akito Tagashita (1 person outside)