Internal-combustion engines – Igniters – Sparkers
Patent
1988-07-15
1990-08-14
Wolfe, Willis R.
Internal-combustion engines
Igniters
Sparkers
439125, F01L 1500
Patent
active
049478095
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to an ignition boot for a spark plug which is usable in an internal combustion engine.
BACKGROUND OF THE INVENTION
It is well known in internal combustion engines that ignition leads are connected to spark plugs which transmit the required energy for sparking of the plugs. In this respect interruption to this energy supply either through incorrect or insufficient connection between the ignition lead and spark plug or interruption by presence of excess moisture is to be avoided. If such does occur the fuel injected into the combustion chamber is not ignited which leads to fouling of the plug and missing of the engine.
With the recent introduction of lead-free fuel onto the Australian market, an additional ramification of the engine missing has arisen due to fuel in the raw state being fed into the catalytic converter in the exhaust system. Recently it has been revealed that the effectiveness of catalytic converters can be reduced dramatically below that prescribed under Australian Emission Regulations by running an engine whilst it is missing for a short time for example 4 minutes. The catalytic converters thus overheated from exothermic reaction with raw fuel cannot be economically reconditioned and thus replacement of the converter is recommended.
Accordingly whilst there have been numerous arrangements to ensure proper connection between an ignition lead and spark plug and also to incorporate covers over the connection to reduce shorting, the introduction of lead-free petrol and catalytic converters has intensified the need to provide improved connections and seals.
With the above needs in mind, an ignition boot is provided which has four separate features. Each of the features is independent of any other of the four and thus it will be readily apparent to those skilled in the art that each of the features could be included into an ignition boot in the absence of the others. The present invention is therefore not specifically restricted to any combination of those aspects though of course the entire combination of the four is the most preferred.
DESCRIPTION OF THE INVENTION
The first aspect of the present invention comprises an ignition boot for a spark plug located in a spark plug receiving cavity of a cylinder comprising a spark plug receiving aperture at one end and sealing means located peripherally at or adjacent the spark plug receiving aperture and urgable against wall(s) of the spark plug receiving cavity thereby substantially preventing ingress of dust or moisture to the spark plug.
Typically the sealing means is a resilient material and by insertion of the boot over the end of the spark plug, forces the sealing ring against said walls.
In one preferred embodiment the sealing means is a ring located about the spark plug receiving aperture of the boot and sealing against the base wall of the spark plug receiving cavity in the cylinder head. With modification the sealing ring may simultaneously seal against the side wall of the cavity.
In a further preferred embodiment the sealing ring is provided adjacent the end of the spark plug receiving aperture of the boot such that it bears solely on the side wall of the cavity in the cylinder head. In this configuration the ring is biased in a direction radially and rearwardly from the receiving spark plug aperture and forms a taper to assist sealing with the cavity wall upon inserting the boot over the spark plug. Alternatively, the ring may extend radially and outwardly of the spark plug receiving aperture.
In a second aspect of the invention an ignition boot is provided for a spark plug having an insulator section and a terminal, the boot comprising a spark plug receiving aperture connecting to a sealing chamber to engage the insulator section, and a first chamber having a transverse dimension substantially exceeding the transverse dimension of the terminal and that part of the insulator section located therein.
As such the first chamber is specifically designed to accommodate both common sizes
REFERENCES:
patent: 2286918 (1942-06-01), Mascuch
patent: 2553114 (1951-05-01), Sailler
patent: 2904769 (1959-09-01), Sampson et al.
patent: 3128139 (1964-04-01), Estes
patent: 4637358 (1987-01-01), Yano et al.
patent: 4768477 (1988-09-01), Richardson
GSA Controls Pty. Ltd.
Wolfe Willis R.
LandOfFree
Ignition boot does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ignition boot, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ignition boot will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-454655