US1423672A - Magneto-ignition system for internal-combustion engines - Google Patents

Description

J. L. MILTON. MAGNETO IGNITION SYSTEM FOR INTERNAL COMBUSTIO N ENGINES.

APPLICATION FILED FEB. 18, I9I3. RENEWED DEC. 16, 1,423,672. Patented July 25, 1922.. I

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J. L. MILTON.

MAGNETO IGNITION SYSTEM FOR INTERNAL COMBUSTION ENGINES. APPLICAHON FILED FEB.18,1913- RENEWED DEC. 16,1920.

1 ,42 3 ,672. Patented July 25, 1922.

3 SHEETS-SHEET 2.

Fig. c3.

J. L. MILTON. MAGNETO IGNITION SYSTEM FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILED FEB. 1a. 1912. RENEWED mac. 16. 1920.

1,423,672. Patnted Jul 25,1922.

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UNITED STATES JOHN LEWIS MILTON, OF CLEVELAND, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

PATENT OFFICE.

THE TEAGLE COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

MAGNETO-IGNITION SYSTEM FOR INTERNAL-COMBUSTION ENGINES.

Application filed February 18, 1913, Serial No. 749,173. Renewed December 16, 1920. Serial No. 431,096.

To all whom it may concern:

Be it known that I, JOHN L. MILTON, a citizen of the United States, residing at Cleveland in the county of Cuyahoga and State of Ohio, have invented a certain new and Improved Magneto-Ignition System for Internal-Combustion Engines, of which the following is a full, clear, concise, and

exact description, reference being had to the accompanying drawings, forming a part of this specification.

My. invention relates to magneto ignition systems for internal combustion engines and one object is to produce a hotter spark than usual with comparatively less expensive apparatus than ordinarily used for this pur pose.

Another object is to construct the genera- 9 tor pole pieces and armature pole shoes so as to alter the normal wave form for the pur pose of giving an increased effective timing range. The fundamental principles of this construction are disclosed in my United States application Serial Number 475,170, filed J any. 30th, 1909 (see Letters Patent No. 1,366,475). Another object of the invention embodied in this ignition system, relates to the compact construction and metho of mounting the external transforming coil, on its nonmagneticcore.

An instance'of my invention is illustrated in the accompanying drawings, in'-which:

Fig. 1 is a diagrammatic representation of the circuit, Fig. -2 is a. combined end elevational and cross sectional view from the driving end of the magneto (the cross sectional view reveals the distributer and brush holder construction), Fig. 3 is an elevational view of the timer end of the magneto without the cover and with the cover holding spring removed'in order to reveal the timer mechanism, Fig. 4 is a vertical axial sectional view of the generator showing the condensers, timer, armature and portions of the dis- 'tributer mechanismpFig. 5'is a cross sectional view,(on enlarged scale) ,of the 'spark gap, bindin post and part of the condenser mounting, ig. 6 is a,detail view of the driving spindle, showing the distributer mounted.

thereonand Figs. 7 and 8 are elevational and cross'sectional views of the transformer coil. Like reference characters are applied to Specification of Letters Patent. I

Patented July 25, 1922.

the same parts throughout the various figures.

Referring first to Fig. 1, it will be seen that the current is supplied by means of a generator G which 'is provided with a rotatable core R and the armature coil W wound thereon. One terminal of the wind -ing W is connected to the distributer seg ment A by means of screw which also makes electrical contact with one side of the condenser F. Two distributer brushes, (ll-b, which are radially related connect by means of wires (1 and b to the primary and secondary of coils CC. The other terminal of the winding W is grounded by means of a. conductor, U.

I illustrate the spark gap terminals which are disposed inside the cylinders at s, s. The

arrangement illustrated is for a 4 cycle, 2

voi

cylinder engine. The current generated by I the generator G is a relatively low tension current and in order that the high tension current may be supplied to the-mainspark gap terminals s-s, I provide transformer coils Gr-G, comprising a primary winding P and a secondary winding S, which are of such construction that they may withstand considerable heat and may therefore be mounted on the enginecylinder or directly on. the spark plug. It will be readily observed that the greater part of the circuit is required to carry merely a low tension current. This transformer coil is coreless and the primary winding is disposed outside the secondary winding. The primary winding and the secondary winding have a "common connection at T while the screw M forms the other terminal of the secondary winding. The screw M is connected, by means of a conductor to the conductor which passes through the insulating sleeve in the spark plug, the inner end f'which serves for one terminal of the spark gap insideof the cylinder.

Each of the transformer coils has the terminal which iscommon to both the primary and secondary windings connected with a respective contact of the distributer, the

other terminal of the secondary winding as preferably before-stated, is conn cted with one of the terminals. of the spar gap, while the other terminal of the spark gap is grounded as indicated. The other terminal of each primary winding is connected to a conductor which terminates either at the spark gap in the primary circuit or in the condenser E, the latter method is the preferred form and is illustrated in Fig. 1.

The timing device is in shunt of the generator'winding W. The condenser F is also in parallel connection or placed directly across the generator windin The magneto machine which I have illustrated diagrammatically at G in Fig. 1 and which is shown in some detail in Fig. 4, is a conventional type shuttle wound armature with the exception of the dampening coils diagrammatically shown at q and 1" which are used for the purpose of retarding magnetic changes at the various speeds. These may be used eitheron the armature or pole pieces, or, they may be used jointly. These retarded magnetic changes are to increase the effective timing range. There can be seen by the diagrammatical representation, Fig. 1, that the. dampening rings 'r-r on the armature are so co-related with the pole pieces that a complete change of the magnetic lines of force cannot suddenly take place. The same diagrammatic representation discloses the pole pieces so arranged as to effect a corresponding condition.

The illustrations 2, 3 and 4 are full size and draw-11 substantially to scale. The pole frame is indicated at 6 and the two horseshoe magnets which are associated therewith are shown at 6 The usual form of construction is followed on the base and end plates, which carry the bearings, on which rotate thearmature s indlesl One spindle, 11, carriesthe cam which actuates the timing lever is, the timing lever carries the platinum point it, which registers with platinum point it which is I mounted on suitable screw, 71?, which is in turn supported by the insulated pedestal 28. The spring 29 makes electrical contact with insert 30 of the bakelite timer cover 31, and

the insert 30 makes electrical contact through supporting spring 32, which is pivoted on pin 33 which in turn is mounted on a conductor block 34 which is mounted in a bakelite casing 35. Connecting screws 36-36, make electrical contact with a supporting member 37 which carries the condenser E, and makes electrical contact with one terminal of same. This end of the condenser is connected to binding post 38 conveniently placed to receive two wires g-g, the ends of which are shown in Fig. 2. The other end of the condenser is connected to a fiat conductor, 39, shown in detail in Fig. 5, which shows very clearly the detail construction of the method of securing the second' terminal of the condenser E to the condenser supporting plate 40. The condenser, its terminals and the fixed spark gap 41 are assemled completely, independent of the remainder of the machine. The tongue 42 of the condenser plate fits into a recess of the cover 43 so as to avoid the necessity of providing a more complicated means of holding. The other end of condenser plate 40 is held in place by means of the screws 36, above referred to. The armature construction in addition-to that above referred to is novel inasmuch as the spindle 44, which carries the non-magnetic armature end, 45, also carries the condenser F. The screw 45 serves the triple purpose of holding the condenser in place, carrying the armature current from the insulated end of winding WV to the segment A of the distributer, and also of helping to hold the distributer insulation 46 in its proper place. Similarly, the screw 45* serves the triple purpose of helping to hold the condenser F in place, connecting one terminal of said condenser to ground and helping to hold the insulation 46 in place. Screws 47 serve to secure the end part 45' of the armature to the body thereof. It is shown in Fig. 6 that the insulation 46 is so shaped as to permit the manipulation of screws 47 without disturbing the electrical or mechanical relation of the condenser and distributer. This is very economical construction and is practicable inasmuch as this distributer does not carry high tension current.

Figs. 7 and 8 show the transformer coil which I prefer to use in connection with this system, though any other suitable form of construction can be employed. The coil, in manufacture, is formed on a fibre tube .50, into which an insert, '51, is placed before the first steps of the impregnation of the winding. This insert 51 is provided with a threaded hole so as to make it readily attachable to any part of the engine, either directly-or by means of a bracket. In the other end of the tube 50 is placed the insert M which forms the inner end of the secondary winding. This end is connected to the spark plug either directly or through the means of a suitable conductor.

Having described the points of the magneto and circuit which differ from the conventional types of this class of ignition ap-- paratus, I wish to enter into a further explanation of my theory of the operation of the circuit which is illustrated in Fig. 1. I do not wish to be limited to this particular circuit, as this magneto and coil may be operated on various circuits. The circuit disclosed here, by means of the timer lever k and cam 0 cause a local or direct short-circuit on the armature W by means of wires 14 and u, and e and e. In the course of operation as the armature rotates the timer interrupts the armature winding at about its maximum electromotive force. The con denser F,-being in parallel with the winding and the timer, is immediately charged and then instantly begins its discharge through the easier path presented to it, which is through the primary of one of the transformer coils which is in series with the condenser E and spark gap X. I believe that it is the first condenser oscillation which generates a high frequency in the secondary winding of the transformer coil, which is .associated with the primary, and through which the condenser has at least partially discharged, the hi h frequency current having onceionized t e spark gap, 8, a low resistance path is at once offered to the electrical energy present in the low tension circuit. A very large intense arc being created at s, I believe that it is caused by the nondissipated current in the armature, together with, possibly, the after oscillations of the condenser. Somewhat similar results are given by this circuit when the condenser E is entirely removed. Under this condition the condenser F discharges at least a part of its oscillation directly through the primary of the transforming coil and across spark gap X. By substituting a kick coil and battery of suflicient voltage for the armature and its winding in the above described circuit, or by substituting a suitable dynamo current, I can secure results similar to those last mentioned. By altering the circuit diagrammatically illustrated in Fi 1 so as to eliminate the'transforming coi s and condenser E and use the auxiliary spark gap, X, as a spark plug electrodes with its usual spark gap I cansuccessfully ignite an explosive mixture.

Having made various combinations of this circuit, together with different proportions and different features which do not substantially change the result I do not wish to be limited beyond the appended claims. Many modifications of'the features of construction may also be made without substantially producing a new result and on this point vI do not wish to be limited beyond the claims attached.

What I claim as new and desire to secure by Letters Patent is:

1. In an ignition generator, the combination with opposite field'magnet poles and an armature operatively mounted between the poles, of a cover plate fitting between the said poles, a condenser and a spark gap structure, the said cover plate, condenser and spark gap structure forming a self-contained unit adapted to be assembled before the cover plate is mounted in the generator.

2. In an ignition generator, the combination with opposite field magnet poles and an armature operatively mounted between the v poles, of a cover plate fitting between the said poles, a condenser, a spark gap structure and electrical connections for said condenser and structure, the said cover plate, condenser, spark gap structure and electrical connections forming a self-contained unit adapted to be assembled before the cover plate is mounted in the generator.

3-. In a miagneto electric machine, the combination with a permanent field-magnet and pole pieces secured thereto, of an armature comprising non-magnetic heads, a generating winding, a condenser, an insulated distributor segment, means for fastening the condenser and distributor segment to one of the said heads, and means for securing said head to the body of the armature, the said winding, condenser and segment being electrically connected and the said securing means being adapted to be removed without disturbing the electrical connections.

4:. In a magneto electric machine, the combination of a permanent magnet, pole pieces secured thereto, a rotating armature, a timer, a removable cover for said timer, an insulated block carried on the magneto housing, an electrical conducting spring arm pivotally secured to said insulated block and serving to hold said timer cover in place, said spring arm having its cover-holding end normally electrically connected with the timer, and an electrical conductor connected to the spring arm and serving to secure the said insulated block to the magneto housing.

5. In a magneto electric machine, the combination of a permanent magnet, pole'pieces secured thereto, a rotating armature, a timer, a condenser, a removable cover for said timer, an electrical conducting spring arm electrically connected with the timer and holding said timer cover in place, an insulating block on the magneto housing to which said electrical conducting spring arm is pivotally secured, and electrical conducting screws serving to secure said block to the magneto housing and make electrical connection between the said spring arm and the condenser. 7

6. In a magneto electric machine, the combination of a permanent magnet, dampened pole pieces secured thereto, and a wire wound armature having dampened pole shoes substantially as described and for the armature having dampening rings surrounding a portion of its periphery.

JOHN LEWIS MILTON.

\Vitnesses:

W. C. KENNINGTON, F. P. MCDERMUI'I, Jr.

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