US796349A - Electrical ignition apparatus for internal-cobustion engines. - Google Patents

Description

No. 796,849 PATENTED AUG. 1, 1906.

v A. J. POSTANS. ELECTRICAL IGNITION APPARATUS FOR. INTERNAL COMBUSTION ENGINES.

APPLICATION FILED OOT. 19,1903.

i'l l UNITED STATES PATENT OFFICE.

ARTHUR JAMES POSTANS, OF SOUTH KENSINGTON, ENGLAND.

ELECTRICAL IGNITION APPARATUS FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented Aug. 1, 1905.

Application filed October 19,1903. Serial No. 177,626.

To all whmn it may concern:

Be it known that I, ARTHUR J AMES POSTANS, engineer, a subject of the'King of Great Britain and Ireland, residing at 155 Fulham road, South Kensington, in the county of London, England, have invented certain new and use-' ful Improvements in Electrical Ignition Apparatus for Internal-Combustion Engines, (for which I have applied for a patent in Great Britain, No. 9,305, dated April 24, 1903;) of which the following is a specification.

This invention relates to an electrical ignition apparatus for internal-combustion engines in which the spark produced on breaking a simple circuit of large inductance is used to ignite the combustible mixture of the engine. To provide the spark required at the proper instant, the circuit includes two breaks, one of which is outside the combustion-chamber and is normally open, while the other is inside the combustion-chamber and is normally closed. IN hen the external break in the circuit is closed, which may be done in any known manner by any convenient moving part of the engine, the current energizes a solenoid or solenoids or an. electromagnet or electromagnets included in the circuit, and by means of the consequent attraction against the force of a spring of a soft-iron armature attached to one of the contact-pieces of the internal break the latter is opened, and the sparkdue to the so-called extra current of the induction-circuit is produced and ignites the charge. A series of such sparks will take place during the time that the external break is closed. When there are two or more cylinders in the engine and a single ignition-circuit, it would then be necessary to provide additional independent external breaks, so as to avoid short-circuiting the battery.

In the accompanying drawings, Figure 1 is an elevation of an ignition apparatus constructed according to the present invention in which the firing-circuit and external break are shown diagrammatically. Fig. 2 is a plan; Fig. 3, a sectional detail showing the arrangement of the internal break, and Fig. 4a diagram showing an arrangement of the external breaks for a four-cylinder engine.

In the case of a single-cylinder engine the electric ignition-circuit includes a suitable battery a, one terminal of which is in connection with one end of the inductance-coil 0 and the other through a circuit-closer Z), operated from any suitable moving part of the engine, with the ignition-plug f or any part in electric connection therewith. The other end of the coil, which preferably encircles a soft-iron core 0, is connected to the spring-piece al, which is supported on but insulated from a bracket 0, in which the coil is supported. The ignitionplug f, to one end of which the bracket 0 is attached by means of the nut f is formed for screwing into the ignition-chamber in the usual way and has a central plug 9, of vulcanized fiber or other suitable insulating material, through an axial hole, in which passes a rod it, of hardened steel or other suitable material. On one end of the rod is adjustably fixed a contact-piece h, which abuts against the spring (Z and is urged forward by it, so as normally to hold the other end of the rod h in contact with the end of a bent rod 70, preferably also of hardened steel, which is screwed into the body of the ignition-plug.

The armature of the electromagnet 0 consists of a soft iron or steel rod Z, journaled in the bracket 0 and having fixed at right angles to its ends and in the same plane with each other two bars or fingers Z of similar material. These fingers are preferably long enough to reach beyond the center of the iron core 0 and are normally held displaced to one side of the core by means of a spring m, fixed on the casing m, which incloses the coil, which engages with a reaction-piece n, fixed on the rod Z, so as to permit the armature to oscillate on either side of its normal position. The rod Z has also fixed to it a pin 0, which projects upward behind a collar 0 on an insulatingsleeve fixed on the rod it.

WVhen the circuit-closer Z) is open, the sparking electrodes It 7c are held in contact by the spring (Z; but as soon as the electromagnet is energized by closing the switch Z the fingers Z of the armature are attracted toward the center of the core 0, thereby turning the rod Z in its bearings, so that the pin 0, pressing against the collar 0, forces the electrode it backward against the spring cZ and causes a break in the circuit at the abutting ends of the electrodes h is, resulting in a spark at that point due to the so-called extra current. The electromagnet again becoming deenergized, the spring 17?. returns the armature to its normal or unattracted position, and the spring CZ tends to close, and if there has been no ignition of the charge in the cylinder will close the break at the electrodes h Z5, and the electromagnet will again become energized if the switch Z is still closed. The time of contact of the circuit-closer Z2 can be variedwithin wide limits; but even the least time of contact obtainable by mechanical means is long enough to produce a series of breaks and makes, and therefore a series of sparks, at the electrodes hit. As soon, however, as the combustible mixture has been ignited the resulting pressure in the cylinder forces the rod h outward against the reaction of the spring d and holds the electrodes la 70 out of contact, at any rate long enough to keep the circuit broken at h is, until it is again broken at the switch 6.

The eccentric engagement of the pin 0 with the collar 0 causes the latter, and with it the electrode h, to turn through a small angle each time the electromagnet is energized, and the regular wear of the sparking surface thus secured not only increases the life of the electrodes, but also the certainty of their action.

When the same battery is used forthe igni tion-circuits of a number of cylinders in which the ignition of the combustible mixture has to occur successively, the circuit-closers for the various circuits must be arranged so that the battery will not be short-circuited. Such a circuit-closer is illustrated diagrammatically in Fig. 4, which shows such an arrangement of circuit for a four-cylinder explosionmotor. One element 0 of each of the circuitclosers is connected to one of the poles of the battery a, and these elements are arranged to be successively displaced by a moving part of the engine, so as to be brought into contact with its fellow element g, each of which is connected to one end of its corresponding ind uctancecoil, the remainder of each of the separate circuits being as shown in Fig. 1.

It is to be understood that the present invention is not to be considered to be limited to the construction herein described and illus trated, which may be varied in many ways as regards constructional details without in any way'departing from the invention. 1

Having thus described the nature of this invention and the best means I know of carrying the same into practical effect, I claim 1. In apparatus of the kind herein described a movable sparking electrode, a collar attached to the electrode and a pin operated by an electromagnet adapted to' engage eccentrically with the collar so as to move the electrode along its axis and at the same time rotate it about its axis, substantially as and for the purpose specified.

2. An electrical igniter for explosion-engines comprising an electromagnet, an armature adapted to be attracted thereby, a fixed electrode and a movable electrode, means actuated by said armature for retracting the said movable electrode, and automatically-operating means for rotating the said movable electrode, substantially as and for the purpose set forth.

3. An electrical igniter for explosion-engines comprising an electromagnet, an armature adapted to be attracted thereby, a fixed electrode and a slidable electrode, means actuated by said armature for retracting the said movable electrode, a spring adapted to retain the said armature in a normal position and a reaction-piece arranged to set the said spring in any other than said normal position.

4. An electrical igniter comprising a sparking plug having a fixed and a movable electrode, means for closing the spark-gap when the pressure in the combustion-chamber of.

the engine falls below a definite amount, and an electricallyoperated device engaging with said movable electrode for withd rawing it from contact with the fixed electrode, and simultaneously rotating it.

5. An electrical igniter comprisinga sparking plug having a fixed and a slidable electrode, said slidable electrode being rotatable and adapted to contact with the fixed electrode, means for causing one of the electrodes to contact with the other, an electrically-operated device engaging with said slidable electrode torotate the same while withdrawing it from contact with the fixed electrode, and means for closing the spark-gap when pressure in the combustion-engine falls below a definite amount.

In testimony whereofI have signed my name to this specification in the presence of two subscribing witnesses.

ARTHUR JAMES POSTANS.

Witnesses:

OLIVER IMRAY, EDWARD GARDNER.

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