US2402539A

US2402539A - Ignition system

Info

Publication number: US2402539A
Authority: US
Publication date: 1946-06-25
Anticipated expiration: 1963-06-25

Description

June 25, 1946. w. w. EITEL 2,402,539

' v IGNITION SYSTEM Filed Oct. 11, 1943 23 Y2, (I x En \M Z! /9 ri s f; 2

HIS ATTORNEY Patented June 2 5, 1946 IGNITION SYSTEM William W. Eitel, San Bruno, Califi, assignor to Eitel-McCullough, Inc., San Bruno, CaliL, a

corporation of California Application October 11, 1943, Serial to. 505,885

Claims. (01. 123148) My invention relates to an ignition system for an internal combustion engine.

The broad object of my invention is to pro-' vide an improved ignition system embodying resonant means located in the combustion chamber and energized by a high frequency 05- cillator to produce a discharge. I

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of my invention. It is to be understood that,

I do not limit myself to this disclosure of species of my invention, as I may adopt variant embodiments thereof within the scope of the claims.

Referring to the drawing:

Figure 1 is a diagrammaticview of an ignition system embodying the improvements of my invention; and

Figure 2 is a detail sectional view showing the portion of the engine cylinder containing the resonant means.

conditions a discharge can be made to occur across the gap, at the open end of the line.

Oscillator 8 may be of any suitable'typeadapted to produce oscillations at the desired frequency. That shown comprises a pair 0f tri0des I! connected in a circuit having a tank coil I! from which energy is transferred by a coil l3 feeding into a transmission line M. The latter may be of any suitable type such as a concentric line comprising 'an outer tubular conductor l6 and an inner conductor l1. As shown in Figure 2, tube i6 is threaded into an aperture extending through the side wall of the combustion cham-" her and is plug ed by a suitable insulator 18 through which inner conductor l1 projects. Conductor I1 is connected to the resonant line adjacent its shorted end.

Means are provided for keying the oscillator with pulses timed with the operation of the enw gine. This is done by discharging condenser l9 Figure 3 is a sectional view similar to Figure 2, showing a modified arrangement.

Figure 44s a detail sectional view of an engine cylinder, disclosing another modified construction.

In terms of broad inclusion, my ignition system for an engine comprises resonant means in the combustion chamber adapted when energized to produce a discharge, a high frequency oscillator, means transferring energy from the oscillator to the resonant means, and means keying the oscillator to energize the resonant means in time with the operation of the engine.

In greater detail, and referring to Figures 1 and 2 of the drawing, my ignition system is shown more or less diagrammatically in conjunction with an engine having acyllnder l andassociat-- ed piston 2. The cylinder (has suitable intake and exhaust valves 3 ported into combustion chamber 5, and piston 2 i connected by a rod 8 to a crank shaft I.

-Resonant means are provided in the combustion chamber for producing a discharge when energized by a suitable oscillator 8. The typeof resonant means shown in Figures 1 and 2 comprises a quarter-wave line made up of two parallel metallic rods 9 secured at one end to the cylline of this kind, when properly. energized, .willinto the oscillator, the discharges being timed by a suitable switching device such as rotatable contactor 2| interposed in lead from the condenser to the oscillator. Contactor 2| is rotated 36 by a suitable drive means (indicated by dot and have a potential node atthe shorted end and a Y potential antinode at the open end. tinder these transmission line is employed comprising two parallel wires or rods 2d projecting into the combustion chamber through a suitable insulator 2s mounted on a, threaded plug 21. The line section projecting into the combustion chamber is substantially ,dwave in length, thus placing the potential node at the chamber wall. This being a tuned line it is understood that the line portions external the cylinder should b some multiple of a quarter-wave. Since the timed line enters the combustion chamber at a potential node the insulation problems at this point are reduced to a minimum.

Figure 4 shows another modification in which the combustion chamber is shaped to form a, resonant cavity having a gap 28 therein adapted to provide a. discharge'when the cavity is'energized. Energy is transferred from the oscillator by a. coninto the resonant cavity.

' I claim:

centric line terminating in'a loop 23 projecting 1. An ignition system for an engine having a combustion chamber, comprising resonant means in the chamber adapted when energized to produce a discharge, a, high frequency oscillator,

means transferring-energy from the oscillator to said resonant means, and means keying the oscillator to energize the resonant means in time with the operation of said engine.

2. An ignition system for an engine having a combustion chamber, a resonant cavity formed means transferring energy from the oscillator to said line, and means keying the oscillator to energize the line in time with the operation of said engine.

4. An ignition system for an engine having a combustion chamber, a resonant line projecting into the chamber. adapted when energized to produce a discharge, a high frequency oscillator, means transferring energy from the oscillator to said line, and means keying the oscillator to energize the line in time with the operation of said engine, the length of the line in said chamber being such as to place a potential node adjacent a wall of the chamber.

5. An ignition system for. an engine having a combustion chamber, a resonant. line projecting into the chamber adapted when energized to produce a discharge, a high frequency oscillator, means transferring energy from the oscillator to said line, and means keying the oscillator to en,- ergize the line in time with the operation of said engine, the length of the line in said chamber being substantially one-quarter wave length at the frequency of said oscillator,

, 'WILLIAM W. EITEL.