Claims
- 1. A sparking plug comprising: a central electrode; a plug screw-thread insulated from said central electrode; and earth electrodes electrically connected to said plug screw-thread; said central electrode having an end, on which is disposed an attachment member consisting at least partially of platinum or a platinum alloy, with spark gaps disposed between said attachment member and said earth electrodes, said earth electrodes extending laterally along side faces of said attachment member; said attachment member being further characterized in that it has the form of a prism, with a top and a base surface, said top surface having diagonal dimensions in the range of a diameter of said central electrode, said top surface facing the combustion chamber of said central electrode, and in that the earth electrodes extend laterally along said side faces of said attachment member and substantially parallel with edges of said top or base surface of said prism.
- 2. The sparking plug according to claim 1, characterized in that the top surface of the attachment member is at right-angles to the longitudinal axis of the central electrode.
- 3. The sparking plug according to claim 1, characterized in that the base surface of the attachment member bears at least partially on the combustion chamber end of the central electrode.
- 4. The sparking plug according to claim 1, characterized in that said attachment member further comprises a central bore which is aligned with a bore in said central electrode, said bores being filled with a fused-in metal or a fused-in metal alloy, particularly hard solder, to connect said attachment member to said central electrode.
- 5. The sparking plug according to claim 1, characterized in that the base surface of the attachment member is directly connected to the combustion chamber end of the central electrode.
- 6. The sparking plug according to claim 1, characterized in that the attachment member takes the form of a right prism.
- 7. The sparking plug according to claim 1, characterized in that the base surface or top surface of the attachment member is rectangular, and is preferably square.
- 8. The sparking plug according to claim 1, characterized in that the base surface or top surface of the attachment member is triangular.
Priority Claims (1)
Number |
Date |
Country |
Kind |
8902032 |
Feb 1989 |
DEX |
|
BACKGROUND OF THE INVENTION
This is a continuation of copending application Ser. No. 07/481,898 filed on Feb. 20, 1990, and now abandoned.
US Referenced Citations (8)
Foreign Referenced Citations (6)
Number |
Date |
Country |
1941979 |
Dec 1980 |
DEX |
3132814 |
Apr 1982 |
DEX |
3730627 |
Mar 1988 |
DEX |
855140 |
May 1940 |
FRX |
239420 |
Sep 1925 |
GBX |
578430 |
Jun 1946 |
GBX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
481898 |
Feb 1990 |
|