Internal-combustion engines – High tension ignition system – Power supply – ignition coil primary – and interrupter element...
Patent
1993-11-16
1995-01-10
Nelli, Raymond A.
Internal-combustion engines
High tension ignition system
Power supply, ignition coil primary, and interrupter element...
123635, 123656, 123654, F02P 312
Patent
active
053797450
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to an ignition system for internal combustion engines with high-tension switches.
More particularly, it relates to an ignition system in which at least one trigger diode cascade, as high-voltage semiconductor switch, is connected in a secondary circuit of each ignition coil prior to each spark plug and changes suddenly from a blocking state to a conducting state at a preselected voltage for generating ignition sparks.
The ignition system mentioned above uses high-voltage switches which are arranged on the secondary side, preferably in the spark plug terminal. Trigger diode cascades are used as high-voltage switching elements. A stack of 10 to 50 trigger diodes is used depending on the electric strength of an individual trigger diode and depending on the desired breakover voltage. With such a high-voltage semiconductor switch which changes suddenly from the blocking state to the conducting state, it is possible practically to eliminate the influences of shunts at the spark plug. Because of their self-capacitance, long ignition lines subsequent to the trigger diode cascade negatively affect the steepening effect of the trigger diode cascade. For this reason, the high-voltage semiconductor switch is preferably arranged in the spark plug terminal. In contrast, relatively long lines prior to the trigger diode cascade have an advantageous influence because, due to their self-capacitance, they suddenly release the stored energy as the high-voltage semiconductor switch becomes conductive. When such semiconductor switching elements are used in double ignition coils, the division of voltage on the secondary side makes it necessary to keep the breakover voltage of the high-voltage semiconductor switches low enough so that this breakover voltage is achieved in every case. However, this has the disadvantage that there is hardly any steepening effect when the breakover voltage is clearly below 11 kV.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an ignition system for internal combustion engines with high-tension switches, which avoids the disadvantages of the prior art.
In keeping with these objects and with others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in an ignition system in which four internal combustion engines, in which a capacitor is connected parallel to the secondary circuit of the ignition coil between the ignition coil and the trigger diode cascade.
When the ignition system is designed in accordance with the present invention, it has the advantage over the prior art that, regardless of the installation location of the high-voltage semiconductor switch in the form of a trigger diode cascade, an additional capacitor is arranged between the ignition coil and the high-voltage semiconductor switch on the secondary side parallel to the secondary winding so that a sufficiently high jump in voltage is achieved at the spark plug even with low system capacitance.
Advantageous further developments and improvements of the ignition system indicated above are made possible by further steps. It is particularly advantageous to use a ceramic capacitor which is dependent on temperature in such a way that the steepening effect is only increased during a cold start and the capacitance of the capacitor decreases sharply during operation due to heating. The increased energy requirement of the ignition system and thus the increased loading of the ignition coil by the capacitor are accordingly limited to the very brief cold start phase.
A further advantage consists in the use of a capacitor in double ignition coils. In this case, only one capacitor need be installed in spite of the allocation of two spark plugs to a coil. This economizes on material and accordingly reduces cost.
Finally, it is advantageous that the capacitor can be switched on or off optionally. Thus, this steepening effect is only enhanced when required by the system, e.g. during a cold start, part
REFERENCES:
patent: 2643284 (1953-06-01), Putnam
patent: 3406672 (1968-10-01), Phillips et al.
patent: 3753428 (1973-08-01), Phillips
patent: 3900017 (1975-08-01), Collins
patent: 4083347 (1978-04-01), Grather et al.
patent: 4203403 (1980-05-01), Fujii et al.
patent: 4411247 (1983-10-01), Kunita et al.
patent: 4463744 (1984-08-01), Tanaka et al.
patent: 5044349 (1991-09-01), Benedikt et al.
patent: 5265580 (1993-11-01), Vogel et al.
Herden Werner
Vogel Manfred
Nelli Raymond A.
Robert & Bosch GmbH
Striker Michael J.
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