Electric lamp and discharge devices – Spark plugs – Particular electrode structure or spacing
Reexamination Certificate
2007-07-31
2007-07-31
Williams, Joseph (Department: 2879)
Electric lamp and discharge devices
Spark plugs
Particular electrode structure or spacing
C313S118000, C313S142000, C313S143000, C313S144000, C123S14300R, C123S1690EB, C123S1690EL
Reexamination Certificate
active
11221918
ABSTRACT:
A spark plug for an internal combustion engine is provided which includes a metal shell, a porcelain insulator, a center electrode, a main ground electrode, and auxiliary ground electrodes. Each of the auxiliary ground electrodes has an inner side surface facing the center electrode through the porcelain insulator to define an auxiliary spark gap between itself and a nose of the porcelain insulator so as to occupy a minimum distance between the porcelain insulator and the auxiliary ground electrode. This avoids a great local increase in electrical field strength on the auxiliary ground electrode to minimize excessive discharge within the auxiliary spark gap to enhance carbon fouling resistance and durability of the spark plug.
REFERENCES:
patent: 4851732 (1989-07-01), Kashiwara et al.
patent: 4914343 (1990-04-01), Kagawa et al.
patent: D344062 (1994-02-01), Kashiwara et al.
patent: 5952770 (1999-09-01), Mueller et al.
patent: 6091185 (2000-07-01), Matsubara et al.
patent: 6229253 (2001-05-01), Iwata et al.
patent: 6316868 (2001-11-01), Ishino et al.
patent: 6531809 (2003-03-01), Benedikt et al.
patent: 6552476 (2003-04-01), Hanashi et al.
patent: 6831397 (2004-12-01), Kanao et al.
patent: 3140006 (2000-12-01), None
Kanao Keiji
Koyama Taiji
DENSO Corporation
Nixon & Vanderhye PC
Sanei Hana Asmat
LandOfFree
Spark plug with increased durability and carbon fouling... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Spark plug with increased durability and carbon fouling..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spark plug with increased durability and carbon fouling... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3738841