US3673998A - Electronic ignition - Google Patents

Abstract

An ignition system for an internal combustion engine including a pair of unilateral current devices and a pair of condensers connected in circuit with the primary of the ignition coil so as to obtain an improved ignition system.

Description

O United States Patent- [151 3,673,998

Phillips 1 July 4, 1972 s41 ELECTRONIC IGNITION 3,405,347 10/1968 Swift ..123/148 [72] Inventor: John P. Phillips, 625 Esther St., Michigan 3443's56 5/1969 Vadalam "123/148 City, 46360 OTHER PUBLICATIONS Filedl J 11, 1970 SCR Designer s Handbook, Robert Murray, 1963 21 APP] NOJ 45 300 Westinghouse, Pages 7- 104, 105

Primary Examiner-Laurence M. Goodridge [52] US. Cl. ..l23/ 148 E, 123/148 R Assistant Examiner-Ronald B. Cox [51] Int. Cl ..F02p 1/00 Attorney-Hill, Sherman, Meroni, Gross & Simpson [58] Field oi Search ..123/l48 E [57] ABSTRACT [56] References Cited An ignition system for an internal combustion engine includ- UNITED STATES PATENTS ing a pair of unilateral current devices and a pair of condensers connected in circuit with the primary of the ignition coil Holthouse 1 so as to obtain an improved ignition ystem 2,353,527 7/1944 Touceda..... 3,264,519 8/1966 Minck 123/148 4 Claims, 1 Drawing Figure ELECTRONIC IGNITION BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates in general to ignition systems and in particular to an improved ignition system for providing increased spark which results in increased performance and in increased gasoline mileage in an internal combustion engine.

2. Description of the Prior Art Conventional internal combustion engine ignition systems utilize a coil having a primary connected in series with a battery and a pair of breaker points. The breaker points are connected in parallel with a condenser and when the breaker points are closed primary of the coil is energized from the battery. When the breaker points break the coil produces a back E.M.F. which is supplied to the condenser and simultaneously a high voltage output is supplied to the distributor from the secondary of the coil. Such systems are subject to oscillation between the condenser and primary of the coil and are also subject to arcing of the breaker points.

SUMMARY OF THE INVENTION The present invention comprises an improved ignition system which utilizes a pair of condensers connected between ground and opposite ends of the primary of the ignition coil and further includes a pair of unilateral current devices with one connected in series with the breaker points and the combination connected in parallel with one of the condensers and a second unilateral current device connected from the junction point between the other condenser and the other side of the primary of the ignition coil and the battery. The ignition system results in much increased spark and gives improved performance in increased gas mileage and results in the breaker points operating much longer than conventional systems without being damaged.

Other objects, features and advantages of the invention will be readily apparent from the following description of a preferred embodiment thereof taken in conjunction with the accompanying drawing, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of this disclosure and in-which:

BRIEF DESCRIPTION OF THE DRAWING The FIGURE illustrates diagrammatically the ignition system of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The FIGURE illustrates the ignition system of an internal combustion engine. The internal combustion engine is designated by numeral 24 and includes spark plugs 26a-26f which are respectively connected to distributor contacts 23a-23 of the distributor 21. The rotating contact 22 of the distributor is connected by lead 27 to the one end of the secondary 19 of the ignition coil. The other side of the secondary 19 is connected to ground. A battery E has one terminal, as for example a negative terminal, connected to ground and has its positive terminal connected to an on-off ignition switch 12. The other side of the ignition switch 12 is connected through a diode D1 to a first end 28 of the primary 18 of ignition coil 17 and to a condenser C2 which has its other side connected to ground. The second side 29 of the primary 18 is connected to ground through a condenser Cl. A pair of breaker points 13 and 14 are controlled by a conventional cam 16 which is mechanically coupled by a shaft 31 or other means to the distributor rotator contact 22. A diode D2 is connected from breaker contact 13 to the junction point between condenser C1 and end 29 of primary l8 and breaker point 14 is connected to ground.

In operation, when the ignition switch 12 is closed and the engine is operating current will flow into the primary 18 of the ignition coil through the closed breaker points 13 and 14. The diodes DI and D2 are poled so that current can flow into the primary 18 when the breaker points 13 and 14 engage. When the cam 16 breaks the contact between the breaker points 13 and 14 a high voltage back E.M.F. will be produced in the primary 18 which will induce a very high voltage in the secondary 19 of the ignition coil 17 which will be supplied by the rotor contact 22 of the distributor to one of the distributor contacts 23a-23f and thus to the spark plugs 26a-26f to produce a high intensity spark resulting in efficient and economic perfonnance of the engine.

The condenser Cl aids in projecting the breaker points 13 and 14 so that excessive and destructive arcing does not occur across them as does the diode D2. The condenser C2 assures that a very hot and effective spark is applied to the plugs 26a-26 by the distributor and the diode D1 prevents the back E.M.F. produced in the coil from being fed back into the battery E. The diode D1 prevents the feedback of electricity into the battery E when the breaker points open and the magnetic field collapses in the coil. The condenser C2 serves as a voltage regulator and prevents the voltage in the primary coil 18 from going so high that voltage breakdown occurs. It has been discovered that the most efiicient level of operation is when the primary voltage is the range from 50 to 75 volts. The capacitor Q in a particular embodiment has a value of 0.2 Mfd-400 volt D. C. Since the impedance of a capacitor varies inversely with frequency according to the relationship of Xc l/21rfc where f is frequency, c is capacitance and Xc is capacitive reactance, it is seen that the higher the frequency the lower will be the capacitive reactance and the capacitor C will tend to shunt high frequency transients to ground as the field in windings l8 and 19 build up and collapse. Thus, condenser c serves as a voltage regulator and prevents excessively high voltages from occurring which can cause insulation failure and voltage breakdown. The windings in the primary 18 and secondary 19 are covered with insulation such as varnish. However, excessively high voltages will tend to cause the insulation to break down at the weakest point and short out the winding where breakdown occurs.

An ignition system constructed according to the present invention has been installed and tested in a vehicle and spark plugs used with the ignition system of the invention have burned substantially cleaner than those operating for the same time in an engine having a conventional ignition system.

The ignition system of this invention provides an improved spark which allows regular gasoline to be used in engines normally requiring premium fuel. This invention is very simple and inexpensive to install in a conventional ignition system of an internal combustion engine in that only two diodes and an additional condenser need be added to the standard system. These are the diodes D1 and D2 and the condenser C2.

It is to be realized, of course, that if the positive terminal 11 of the battery E is connected to ground and the negative terminal 10 is connected to the ignition switch 12, that the polarity of the diodes D1 and D2 would be reversed.

It can be seen that this invention provides an improved i gnition system which results in increased spark and produces improved performance and increased gasoline mileage in an internal combustion engine. Although the invention has been described with respect to a preferred embodiment, it is not to be so limited as changes and modifications may be made therein which are within the full intent and scope of the invention as defined by the appended claims.

I claim:

1. In an ignition system for an internal combustion engine where there is a source of electrical energy and a distributor comprising:

step-up transformer means having a primary and secondary windings, said distributor connected to said secondary winding;

a first capacitor connected between on end of said primary winding and ground and having a value in the range of 0.1 to 0.3 microfarads;

a second capacitor connected between the second end of said primary winding and ground;

a pair of breaker points with one connected to ground;

a first unilateral current means connected between the of electrical energy.

second breaker point and said second end of said primary 2. In an ignition system according to claim 1 wherein the wmdmg; other terminal of said source is the negative terminal.

a second unilateral current means connected between one terminal of said source of electrical energy and said one 5 end of said primary winding and the other terminal of said source of electrical energy connected to ground; and

wherein said first and second unilateral current means are poled so as to pass current in the same direction through said breaker points, said primary winding and soud source 3. In an ignition system according to claim 1 wherein said other terminal of said source is the positive terminal.

4. In an ignition system according to claim 1 including an ignition switch connected in circuit with said primary winding and said source of electrical energy.

Claims (4)

1. In an ignition system for an internal combustion engine where there is a source of electrical energy and a distributor comprising: step-up transformer means having a primary and secondary windings, said distributor connected to said secondary winding; a first capacitor connected between on end of said primary winding and ground and having a value in the range of 0.1 to 0.3 microfarads; a second capacitor connected between the second end of said primary winding and ground; a pair of breaker points with one connected to ground; a first unilateral current means connected between the second breaker point and said second end of said primary winding; a second unilateral current means connected between one terminal of said source of electrical energy and said one end of said primary winding and the other terminal of said source of electrical energy connected to ground; and wherein said first and second unilateral current means are poled so as to pass current in the same direction through said breaker points, said primary winding and soud source of electrical energy.

2. In an ignition system according to claim 1 wherein the other terminal of said source is the negative terminal.

3. In an ignition system according to claim 1 wherein said other terminal of said source is the positive terminal.

4. In an ignition system according to claim 1 including an ignition switch connected in circuit with said primary winding and said source of electrical energy.

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